CN216766009U - Landfill odor adsorption system - Google Patents

Abstract

The utility model provides a landfill odor adsorption system which can efficiently absorb H in a landfill₂And S. The system comprises at least one middle adsorption subsystem and a topmost field-closing adsorption subsystem; the middle adsorption subsystem comprises three functional layers, namely an upper gas collecting layer, an odor adsorption layer II and a lower gas collecting layer III from top to bottom in sequenceA functional layer; the sealing adsorption subsystem comprises six functional layers which are sequentially from top to bottom: the device comprises a vegetable layer, a drainage layer, an impermeable layer, a guide and exhaust layer, an odor adsorption layer I and a gas collection layer I; the odor adsorption layer I and the odor adsorption layer II are made of odor adsorption materials, and the odor adsorption materials are regeneration fine materials; the particle size distribution curve of the odor adsorbing material shows a saddle shape.

Description

Landfill odor adsorption system

Technical Field

The utility model relates to the technical field of refuse landfill, in particular to an odor adsorption system of a refuse landfill.

Background

In recent years, with the continuous and rapid development of national economy and the accelerated process of urbanization in China, the urban garbage is increased rapidly. By 2012, the clean transportation amount of domestic garbage in China is about 1.71 hundred million t, and more than 60 percent of domestic garbage is treated in a sanitary landfill mode except that a small amount of domestic garbage is treated in a mode of incineration, composting and recycling. The domestic garbage contains a large amount of organic matters, and a large amount of malodorous substances are released in the landfill process. Among the malodorous substances, hydrogen sulfide (H) is particularly preferred₂S) is most typical and common.

H in landfill₂The S malodour is mainly from the oxidation of sulphur-containing organic matter and the reduction of sulphate under anaerobic conditions. At the beginning of landfill, organic sulfur-containing components (such as sulfur-containing vitamins or proteins) in the garbage are decomposed by microorganisms to generate H₂S, and a large amount of sulfate is accumulated; in the middle and later stages, anaerobic microorganisms (mainly sulfate reducing bacteria) utilize various organic matters or hydrocarbons to reduce sulfate, and H is formed under the dissimilation action₂S, the process is also a landfill H₂The main source of S.

H₂S has irritant and suffocating odor of rotten egg, and is exposed to H₂The S environment can cause various eye, respiratory and neurological diseases, even shock and death, and has great harm to the health of workers and surrounding residents. In recent years, urban domestic garbage landfill sites such as Beijing, Shanghai, Guangzhou, Shenzhen and the like frequently generate stink pollution outbreak events, which have great influence on the quality of life of surrounding residents and cause serious social problems. Therefore, the H of the refuse landfill is effectively treated₂S malodorous contamination reductionThe damage to the surrounding ecological environment and the protection of the health of people become important contents of the comprehensive treatment of the refuse landfill.

Refuse landfill H₂Pollution control of S malodour may be by source suppression of H₂S production and end reduction H₂The discharge of S is realized.

In general, H is suppressed from the source₂The conventional way of generating S is: (1) inhibiting the activity of microorganisms in the system, mainly by adding alkaline substances such as sodium hydroxide, calcium hydroxide and the like to improve the pH value or adding a bactericide; (2) the activity of sulfate reducing bacteria is inhibited, and the oxidation-reduction potential is improved mainly by injecting substances such as oxygen, nitrate and the like. However, in practice, this does not work well.

H₂S malodour end control is mainly by H in landfill gas₂S decontamination, and blanket optimization for H reduction₂The discharge of S and other terminal control means.

The purification of the landfill gas mainly comprises the steps of collecting and purifying the landfill gas generated in the garbage degradation process in a centralized way through a gas guide and discharge and collection system in a landfill. However, the prior investment and operation cost of the technologies are high, and many landfill sites in China also lack perfect landfill gas dumping and collecting systems, so that the practical application process of the technologies in large landfill areas is limited.

At present, landfill H₂S malodor control the most common approach is to use a landfill cover to achieve in situ control of malodor.

The choice of materials for the landfill layer is directly related to the effectiveness of the odor in-situ control. Although the traditional clay covering technology is mature, the traditional clay covering technology has the defects of poor deodorization effect, large occupied storage capacity, precious and unavailable clay resources, high material price, influence on the transportation of methane and percolate and the like. The ideal landfill casing material should generally have the following physical characteristics: high specific surface area, high moisture retention, high mechanical strength, lower bulk density, high porosity, high buffering capacity, easy availability, low cost, low transportation cost, long service life, and the like. However, no one has found an ideal material that meets this characteristic. Therefore, there is a need to find a more suitable landfill casing material.

The covering layer of the refuse landfill is divided into a middle covering layer and a sealing covering layer.

The intermediate coating layer is a temporary coating layer that is required for bare garbage due to processes such as spreading, leveling, and compacting, and migration of a working surface during a landfill operation. The functions of the intermediate covering layer mainly comprise: (1) a large amount of leachate generated by a large amount of rainwater due to the long-time exposure of the garbage is avoided; (2) inhibiting the release of malodors into the atmosphere; (3) reduce mosquitoes and flies and improve the bad visual environment.

Wherein, the capping overburden layer is mainly used for seepage control and gas sealing. Seepage prevention is to prevent rainfall, ground runoff, underground water and the like from infiltrating into garbage, so that the yield of percolate is reduced. The gas is closed, namely the gas overflow of the landfill is reduced, including the odor overflow is reduced, and further the influence of the landfill on the surrounding environment and the life of residents is reduced.

At present, geotechnical composite materials (such as HDPE films) and clay and other anti-seepage materials are mainly adopted in China for intermediate covering and field sealing covering.

As a cover material, the geocomposite material has problems in that it has a high construction quality requirement, is expensive in construction cost, is easily pierced by hard and sharp garbage components to be deteriorated, and the like. Furthermore, HDPE films do not absorb or handle H2S, and therefore, large amounts of gas often collect below the film causing blistering and thus affecting the life of the film.

The soil intermediate covering layer has the advantages of wide material source, low cost, stability and the like, but the soil intermediate covering layer also has the defects of weakening the stability of the garbage body, occupying the storage capacity, consuming soil resources, influencing the construction, having poor economy and the like due to low strength. In order to solve the problems, the CN 201810659898-intermediate covering layer of the refuse landfill, the preparation method and the application thereof propose to use the recycled aggregate to construct the intermediate covering layer so as to achieve the purpose of improving the mechanical properties of the refuse body through the reinforcement effect of the recycled aggregate and provide the anti-seepage and air-blocking functions to a certain degree. Its air-blocking function is to reduce the passing through of the odor through the low permeability layer.

However, both the earth covering and the covering built from recycled aggregates have several serious drawbacks: (1) these coatings do not absorb or treat H₂S is used as the purpose, and only provides a barrier for isolating and preventing overflow; (2) due to H₂S is not absorbed or treated, H₂S is accumulated under the low-permeability layer, the air pressure is increased along with the time, and finally the air inlet pressure value of the low-permeability layer is broken through to form a through passage, so that the air closing function is lost.

SUMMERY OF THE UTILITY MODEL

In order to solve the problems, the utility model provides an odor adsorption system for a refuse landfill, which can efficiently absorb H in the refuse landfill₂S。

The object of the utility model is achieved in the following way: a landfill odor adsorption system comprises at least one middle adsorption subsystem and a top sealing adsorption subsystem; the middle adsorption subsystem is laid as temporary covering and temporary adsorption after each landfill operation is finished, and is clamped in the garbage body after the next landfill operation, and the closing adsorption subsystem is laid after the landfill operation is finished, so that a garbage body-middle adsorption subsystem … … -a garbage body-closing adsorption subsystem is finally formed, and the garbage body-middle adsorption subsystem is of a composite structure formed by staggered overlapping of the garbage body-middle adsorption subsystem, namely, the garbage body after the landfill operation is finished is respectively arranged above and below the middle adsorption subsystem; the middle adsorption subsystem comprises three functional layers, namely an upper gas collecting layer, an odor adsorption layer II and a lower gas collecting layer from top to bottom in sequence; the sealing adsorption subsystem comprises six functional layers which are sequentially from top to bottom: the device comprises a vegetable layer, a drainage layer, an impermeable layer, a guide and exhaust layer, an odor adsorption layer I and a gas collection layer I; the odor adsorption layer I and the odor adsorption layer II are made of odor adsorption materials, and the odor adsorption materials are regeneration fine materials; the particle size distribution curve of the odor adsorption material presents a saddle shape, and specifically, according to the soil mechanics standard, the particle size grading curve characteristics of the regenerated fine materials need to meet the following conditions: (a) the maximum grain size is not more than 2 mm; (b) effective particle sized₁₀Not more than 0.005 mm; (c) d is not less than 1.2mm₉₀Less than or equal to 1.8 mm; (d) the non-uniformity coefficient CU is more than or equal to 5; (e) coefficient of curvature C_CBetween 1 and 3, i.e. 3. gtoreq.C_CNot less than 1, the compactness is not less than 95 percent respectively, and the air permeability coefficients of the odor adsorption layer I, the odor adsorption layer I and the odor adsorption layer II are 10 respectively under the maximum dry density^-6m/s—10^-8m/s, air inlet values of 1 kPa-10 kPa respectively, water absorption rates of more than or equal to 10% respectively, and pore water saturation of 60% -90% respectively.

The recycled fine material is formed by mixing recycled fine aggregate prepared by recycling construction waste and recycled powder. The ratio of concrete to mortar in the recycled construction waste for preparing the recycled fine aggregate and the recycled powder is more than or equal to 95 percent, and the strength of the original concrete is not lower than C30.

The concrete is of various types, wherein the most widely applied concrete is cement concrete, and the concrete in the utility model is particularly cement concrete, namely concrete prepared by using various types of cement as cementing materials. The cement clinker contains calcium oxide, such as portland cement, ordinary portland cement, portland slag cement, pozzolanic portland cement, fly ash portland cement, composite portland cement, moderate-heat portland cement, low-heat portland slag cement, rapid-hardening portland cement, sulfate-resistant portland cement, white portland cement, road portland cement, masonry cement, oil well cement, and gypsum slag cement.

The recycled construction waste contains quicklime or hydrated lime, the odor adsorption action mechanism of the odor adsorption material is that the construction waste regeneration fine material is used as an odor adsorption layer material, and unreacted quicklime (CaO) or hydrated lime (Ca (OH) remains in the construction waste₂) The alkaline substance and the acidic substance (mainly H) in the odor₂S) carrying out acid-base neutralization reaction, wherein the chemical reaction equation is as follows:

in order to generate and develop the chemical reaction, some environmental conditions, such as a large specific surface area to increase the reaction contact area, a humid environment, etc., are required. Therefore, in the present invention, the theoretical adsorption capacity is controlled by controlling the material properties, particle size distribution, thickness of the adsorbent layer, etc. of the odor adsorbent, and the adsorption effect is further controlled by controlling the degree of compaction, the fine particle ratio, etc. to control the contact area between the odor and the adsorbent, the water content of the odor adsorbent, the odor passage amount, the odor passage rate, the odor passage time (which can be regarded as the odor adsorption reaction time), etc.

The upper gas collecting layer and the lower gas collecting layer of the middle adsorption subsystem adopt recycled coarse aggregate which is recycled and prepared from construction waste buried in a refuse landfill, the thickness is 0.2-0.4m, the particle size is 20-40mm, and the compaction relative density is more than or equal to 0.9; the odor adsorption layer II of the middle adsorption subsystem adopts the odor adsorption material, and the thickness is 0.3-0.6 m.

The sealing adsorption subsystem comprises six functional layers which are sequentially from top to bottom: vegetable layer, drainage blanket, barrier layer, drainage layer, odor adsorption layer I, gas collection layer I. The vegetation layer adopts natural soil and surface layer nutrient soil to meet the nutrient requirement of plant growth, the thickness of the vegetation layer meets the requirement of the root system of planted vegetation, the thickness of the vegetation layer is more than or equal to 0.5m, the vegetation layer soil is compacted in a layering way, and the compaction degree is not less than 80%; the raw material of the drainage layer is recycled coarse aggregate prepared by recycling construction waste buried in a refuse landfill, the thickness is 0.2-0.4m, the particle size is 20-40mm, and the compacted relative density is more than or equal to 0.9; the raw material of the impermeable layer is recycled fine aggregate prepared by recycling construction waste buried in a refuse landfill site, the maximum particle size of the recycled fine aggregate is 2mm, and the effective particle size d of a particle size grading curve₁₀Not more than 0.01mm, coefficient of non-uniformity C_UNot less than 5, coefficient of curvature C_CBetween 1 and 3, i.e. 3. gtoreq.C_CNot less than 1, compactness not less than 95%, and permeability coefficient between 10^-9m/s -10^-6m/s, the water absorption is more than or equal to 8 percent, and the unsaturated soil mechanical air inlet value is more than or equal to 5 kPa; the raw material of the guide and discharge layer is recycled and prepared recycled coarse aggregate from construction waste buried in a waste landfill site; the thickness of the guide and drainage layer is 0.2-0.4m, the particle size is 10-40mm, the compaction relative density is more than or equal to 0.9, and the unsaturated soil mechanical air intake value is not more than 1 kPa; the difference value of the air inlet values between the recycled fine aggregate of the impermeable layer and the recycled coarse aggregate of the guide and discharge layer is more than or equal to 4 kPa; the odor adsorption layer I adopts the odor adsorption material, and the thickness is 0.4-1.0 m; the air collecting layer I is positioned between the odor adsorption layer I and the garbage body, is constructed by regenerated coarse aggregate, has the thickness of 0.3-0.5m, the particle size of 20-40mm and the compacted relative density of not less than 0.9.

The landfill odor adsorption system is characterized in that a water-permeable and air-permeable isolating material layer for preventing raw materials of each layer from being mixed is arranged between each layer for separation.

The landfill odor adsorption system H₂The odor adsorption method mainly realizes odor adsorption through a combined adsorption system consisting of a plurality of intermediate adsorption subsystems constructed during the step-by-step landfill adsorption and a field-closing adsorption subsystem for final adsorption; the middle adsorption subsystem is used as a temporary cover to perform temporary odor adsorption when the landfill is intermittent, and can be used as a middle interlayer of the garbage body to continue performing odor adsorption after the landfill is closed; the odor adsorption in the sealing adsorption subsystem is mainly realized by gas collection of a gas collection layer I, adsorption of an odor adsorption layer I, gas collection of a guide exhaust layer and adsorption of an impermeable layer, and the adsorption of the odor adsorption layer I is mainly used, and the adsorption of the impermeable layer is assisted.

The anti-seepage function of the odor adsorption system is realized by a double capillary retardant covering layer which is formed by an anti-seepage layer and a guide and discharge layer to form a first heavy capillary retardant covering layer and a second heavy capillary retardant covering layer which is formed by the odor adsorption layer I and the gas collection layer I, and the anti-seepage of the first heavy capillary retardant covering layer is taken as a main part, and the second heavy capillary retardant covering layer is taken as an auxiliary part.

The odor adsorption system of the refuse landfill is characterized in that an air collecting layer air extractor is arranged on the side part of the air collecting layer I.

The regenerated coarse aggregate, the regenerated fine aggregate and the regenerated powder required by the odor adsorption system of the refuse landfill are prepared by recovering construction wastes. The construction waste also refers to waste concrete construction waste. The original concrete strength of the construction waste for preparing the odor adsorption layer material is not lower than C30, and the original concrete strength of the materials of other layers except the vegetation layer is not lower than C10. The recycled fine material is a mixture prepared by mixing recycled fine aggregate and recycled powder according to a certain proportion, and the parameter performance requirements are as above.

The odor adsorption layer of the utility model refers to an odor adsorption layer I and an odor adsorption layer II.

The landfill odor adsorption system provided by the utility model controls theoretical adsorption capacity by controlling material characteristics, particle size gradation, adsorption layer thickness and the like of the odor adsorption layer, and controls the contact area of odor and an adsorption material, the water content of the odor adsorption layer, the odor throughput, the odor passing rate, the odor passing time (namely odor adsorption reaction time) and the like by controlling the compactness, different particle size proportions of recycled aggregates and the like, thereby further controlling the adsorption effect. And prevent the seepage of foul smell through foul smell adsorbed layer I, I gas collection of gas collection layer to increase the adsorption efficiency of foul smell adsorbed layer I. And further, the adsorption effect of the odor adsorption layer I is further improved through the water storage, seepage prevention, moisture preservation, gas collection and odor adsorption functions of the gas collection layer I and the gas guide and discharge layer together. The middle adsorption subsystem can perform temporary odor adsorption on one hand, and can perform odor adsorption continuously as a middle interlayer of the garbage body after the garbage is sealed on the other hand.

The odor adsorption material in the patent has the main characteristics that:

(1) the specific surface area is large. It is known that the odor adsorption reaction mainly occurs on the surface of the adsorbent material, and that increasing the specific surface area of the adsorbent material increases the reaction with H₂The contact area of S gas is increased, so that odor adsorption chemical reaction is increased, and odor adsorption is increased. One of the reasons for using the construction waste recycled fines as odor adsorbing material proposed by the present invention is that the recycled fines have finer particles, which can significantly increase the surface area. At the same time, the recycled fines are also a typical porous material, the pores of whichThe gaps mainly comprise primary pores and regenerative pores, and the pore volume of the gaps is much larger than that of natural aggregates and soil with the same grain size grading. The primary pores are mainly the primary pores on the surface of the mortar generated by foaming and other reasons in the concrete preparation process, and the regenerated pores are new cracks or pores generated in the preparation process of recycled fine material crushing. The increase of pores and cracks can greatly increase the specific surface area of recycled aggregate and increase an odor adsorption layer and H₂The contact area of S and further improves the odor adsorption capacity.

(2) More fine particles and stronger adsorption capacity. The odor adsorption material provided by the utility model mainly comprises cement, and sand and stone materials in the original concrete have no adsorption capacity. The cement mortar content in the fine particles in the recycled aggregate is higher, so that the odor adsorption capacity of the recycled aggregate can be effectively improved by increasing the proportion of the fine particles.

(3) The air permeability coefficient is small, and the passing amount and the passing time of the odor in the odor adsorption layer can be effectively controlled. By reducing the throughput between units and extending the transit time, the adsorption effect can be improved.

(4) The alkaline environment provided by the odor adsorption layer can effectively inhibit the generation of odor. According to the report of literature, the pH value of the compacted and recycled aggregate is generally higher than 9, and the pH value of the compacted and recycled aggregate exceeds the suitable pH value environment of aerobic/anaerobic microorganisms for garbage degradation, so that H can be effectively inhibited₂And (4) generating S.

(5) High water absorption and good water holding capacity. The research proves that: in the environment with higher water content, the construction waste recovers fine aggregate and H₂The adsorption reaction of S is accelerated, and odor can be better adsorbed. Generally, the recycled aggregate has a moisture content 15 times that of the natural aggregate and a water absorption 10.2 times that of the natural aggregate, mainly because the recycled aggregate itself has a large porosity. The pores in the recycled aggregate comprise pores between particles and pores inside the aggregate particles. Thus, in compacting the recovered aggregate layer, moisture may be present in the pores between the aggregate particles, as well as into the pores inside the particles. In addition, the cement mortar adhered to the surface of the recycled aggregate has better hydrophilicity according to the basic theory of unsaturated soil mechanicsThe compacted recycled aggregate has better water holding capacity and can absorb and hold water more easily.

(6) The strength is high. The middle adsorption subsystem needs to have better mechanical properties so as to be clamped in the garbage at different layers to form a reinforcement effect and improve the mechanical stability of the whole garbage body. According to literature reports, the mechanical strength of compacted recycled aggregates is much greater than that of natural soil or gravel of the same size grading. The recycled aggregate is used as the material of the middle adsorption subsystem, so that the mechanical property of the middle adsorption subsystem can be greatly improved, and the stability of the garbage body is further improved.

(7) Low cost and easy obtaining. Odor adsorption is a technology and materials that are numerous, but generally cost prohibitive and require large scale long distance transport, which results in low economics. Therefore, the odor adsorbing material is preferably a material which is low in cost and easy to obtain.

Compared with the prior art, the utility model has the beneficial effects that:

(1) the concept of adsorbing garbage odor by garbage is provided, so that the recycling of the construction garbage is realized, the energy is saved, the emission is reduced, and the environment is protected. The utility model creatively provides a method for adsorbing odor generated by landfill garbage by using the landfill garbage, so that the building garbage is recycled, energy is saved, emission is reduced, and the method is green and environment-friendly.

(2) Providing a catalyst consisting of₂S absorption treatment is an odor adsorption system for realizing odor treatment. The utility model provides an odor adsorption system for realizing odor adsorption in an adsorption mode. The middle adsorption subsystem can be used for temporary odor adsorption after single landfill operation is finished, and can also be used as a middle interlayer of the garbage body for continuing odor adsorption after the landfill is closed.

(3) Can effectively inhibit H₂And (4) generating S. The odor adsorption layer and the air collection layer of the odor adsorption system provided by the utility model adopt construction waste to recover aggregates, according to the report of documents, the pH value of the compacted and recovered aggregates is generally higher than 9 and exceeds the suitability of aerobic/anaerobic microorganisms for waste degradationThe pH value environment can effectively inhibit H₂And (4) generating S.

(4) The permeability of the garbage body is improved, the gas collection and pumping capacity is improved, the degradation of the garbage body is accelerated, and the odor adsorption effect is improved. The middle adsorption subsystem in the odor adsorption system provided by the utility model contains an upper air collecting layer and a lower air collecting layer which are constructed by high-permeability recycled coarse aggregates. Along with the landfill operation, a layer of garbage is stacked in a middle adsorption subsystem to form a composite structure with a plurality of good permeability and a gas collection function. The composite structure can greatly improve the permeability of the garbage body, improve the gas collection and pumping capacity in the later maintenance process, and can accelerate the degradation of the garbage body and the methane (CH) generated by the degradation of the garbage body by matching with engineering measures such as ventilation and exhaust and the like₄) The pumping capacity of (2). In addition, the permeability of the garbage body is improved, which is also beneficial to H₂S enters the upper and lower air collecting layers and the odor adsorption layer II, and the air pressure of the upper and lower air collecting layers can be controlled by matching with engineering means, so that the pressure required by the optimal odor adsorption reaction is maintained, and H is promoted₂Adsorption effect of S gas. A gas collection layer I is also arranged in the sealing adsorption subsystem, and a similar effect can be provided.

(5) Improving the moisture-keeping capacity of the adsorption system to maintain the garbage and the odor adsorption layer in the adsorption system at proper humidity, thereby producing proper H₂S adsorption reaction environment, accelerating H₂S adsorption reaction is carried out. The sealing adsorption subsystem in the odor adsorption system uses a double capillary retardation system consisting of an impermeable layer, a drainage layer, an odor adsorption layer I and a gas collection layer I to perform impermeable, gas-closing and moisture-keeping. Under the action of the double capillary retardation system, rainwater cannot permeate into the sealing adsorption subsystem and the garbage body; meanwhile, the moisture in the sealing adsorption subsystem and the garbage body cannot evaporate into the air, so that the stability of the moisture content in the sealing adsorption subsystem and the garbage body is ensured. In the actual work process, can carry out the preliminary treatment to the moisture content of landfill rubbish before laying odor adsorption layer I, also can retrieve the aggregate to the thickness of gas collection layer I and odor adsorption layer I and carry out the preliminary treatment to guarantee the rubbish body and gas collection layer I andthe moisture content of the odor adsorption layer I reaches a preset value. The pretreatment means comprises sprinkling, stirring, drying, insolating, air drying and the like. For the sealing adsorption subsystem treated by odor adsorption, the preset water content of the garbage body, the gas collection layer I and the odor adsorption layer I depends on the progress of odor adsorption reaction.

(6) Adsorption of H by construction waste from landfills₂S, local materials are used, a large amount of odor adsorption materials do not need to be transported outside, and the defect that the traditional odor adsorption materials and the constructed soil covering layer consume the storage capacity of the landfill site is overcome. H according to the utility model₂The S absorption treatment method does not need to transport a large amount of soil and odor adsorption materials from other places, and only needs to use local materials and recycle the construction waste buried in the landfill site. Therefore, the odor adsorption system of the present invention, which is intended to perform the odor adsorption treatment, does not require transporting a large amount of odor adsorbing material from the outside; meanwhile, the defect that a large amount of engineering materials need to be transported from outside the traditional soil covering layer is avoided, and the defect that the storage capacity of the landfill is seriously consumed due to the fact that the traditional soil covering layer is too thick is overcome.

(7) The garbage form of the landfill and the construction process of the landfill operation are more reasonably arranged, the storage capacity of the landfill is increased, and the odor adsorption effect is improved to the maximum extent. The landfill garbage body is limited by mechanical characteristics, and the height, gradient, single landfill layer thickness and other morphological parameters of the landfill garbage body are limited. The odor adsorption system is constructed by high-strength recycled aggregate, and the implementation of the odor adsorption system enables the structure after sealing to be changed into 'garbage body-middle adsorption subsystem- … … -garbage body-sealing adsorption subsystem'. The garbage body formed by staggered superposition of the garbage body-middle adsorption subsystem composite structure can play a role in mechanical reinforcement due to higher mechanical strength of the middle adsorption subsystem, so that the mechanical property and mechanical stability of the garbage body are improved. Therefore, the implementation of the utility model eliminates the restriction factors, so that the form of the landfill garbage can be more reasonably arranged, the landfill garbage can be higher, the gradient can be larger, and the storage capacity of the landfill is increased. On the other hand, the storage capacity occupied by the construction waste can be released by consuming the construction waste of the landfill, so that the storage capacity of the landfill is increased at another angle. In addition, because no other limiting factors exist, the design concept of the landfill operation construction process of the garbage body is mainly to improve odor adsorption to the maximum extent, the thickness of a single landfill layer and the thickness of a middle adsorption subsystem layer are reasonably set, and the landfill operation process is reasonably set.

(8) A large amount of construction waste of the landfill is consumed, and the storage capacity of the construction waste is released. In the traditional refuse landfill, a large amount of storage capacity is occupied by construction wastes. The utility model relates to an odor adsorption system, which uses recycled materials prepared by recycling landfill construction waste, uses recycled aggregates prepared from the construction waste in the odor adsorption system, and can effectively consume and utilize the construction waste, thereby releasing the storage capacity occupied by the construction waste in the landfill and improving the economic benefit and the social benefit of the landfill.

(9) Convenient material acquisition, low manufacturing cost, good durability, simple later maintenance and low cost. The odor adsorption system related by the utility model mainly takes building garbage in a landfill site as a raw material, thereby avoiding the need of transporting a large amount of soil resources from the outside and high material cost and transportation cost of the traditional soil covering layer. In addition, the recycled aggregate has good material stability and durability, the adsorption system has stable structure, simple maintenance and low maintenance cost.

Drawings

FIG. 1 is a schematic view showing the construction of an odor adsorption system for a refuse landfill.

FIG. 2 is a schematic diagram of the configuration of the lock-out adsorption subsystem.

FIG. 3 is a schematic diagram of the configuration of the intermediate adsorption subsystem.

Figure 4 is a typical grain grading curve for each functional layer.

Fig. 5 is a schematic view showing the principle of odor adsorption in the block adsorption subsystem.

Fig. 6 is a schematic view of the principle of odor adsorption in the intermediate adsorption subsystem.

FIG. 7 is a schematic view of the principle of anti-seepage and air-tight of the enclosure adsorption subsystem.

The figure is as follows: 1. vegetation; 2. a vegetable layer; 3. a drainage layer; 4. an impermeable layer; 5. a guide and discharge layer; 6. an odor adsorption layer I; 7. a gas collecting layer I; 8. a waste body; 9. a water permeable, air permeable insulating material layer; 10. an upper gas collecting layer; 11. an odor adsorption layer II; 12. a lower gas collecting layer; 13 a guiding and exhausting layer air extracting device; 14. an air extraction device of the air collecting layer I; 15. an upper gas collecting layer air extractor; 16. a lower gas collecting layer air extractor; 17 a barrier liner layer; 18 sealing adsorption subsystem; 19 an intermediate adsorption subsystem; 20, rainfall is carried out; 21 slope runoff; 22, laterally guiding and draining the drainage layer; and 23, conducting layers of lateral conducting rows.

Note that: in the present embodiment, the drainage layer, the drainage guide layer, the gas collection layer i and the upper and lower gas collection layers of the intermediate adsorption subsystem all use recycled coarse aggregate with the same particle size, and therefore the particle size curves of the above materials are overlapped in fig. 4. In this embodiment, the odor adsorption layer i of the closed adsorption subsystem and the odor adsorption layer ii of the intermediate adsorption subsystem are made of the same material, and therefore, the particle diameter curves of these two adsorption layers coincide with each other in fig. 4.

Detailed Description

The utility model will be described in detail with reference to the drawings and specific embodiments thereof, it being understood that the utility model is illustrative and not restrictive in character, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope of the utility model as defined by the appended claims.

As shown in fig. 1 to 7, an odor adsorption material for a refuse landfill is prepared by mixing recycled fine materials with recycled fine aggregates prepared from recycled construction wastes, wherein the ratio of concrete to mortar in the construction wastes for preparing the recycled fine aggregates and the recycled powder is not less than 95%, the particle size distribution curve of an odor adsorption layer is saddle-shaped, and specifically, according to the soil mechanics standard, the particle size grading curve of the recycled fine materials meets the following conditions: (a) the maximum grain size is not more than 2 mm; (b) effective particle diameter d₁₀Not more than 0.005 mm; (c) d is not less than 1.2mm₉₀≤1.8mm；(d) The non-uniformity coefficient CU is more than or equal to 5; (e) coefficient of curvature C_CBetween 1 and 3, i.e. 3. gtoreq.C_CNot less than 1, the compactness not less than 95 percent, and the air permeability coefficient of the odor adsorption material under the maximum dry density is 10^-6m/s—10^-8m/s, an air inlet value of 1 kPa-10 kPa, a water absorption rate of more than or equal to 10 percent and pore water saturation of 60 percent-90 percent. The odor adsorbing material is mainly used for constructing an odor adsorbing layer I6 or an odor adsorbing layer II 11.

An odor adsorption system for a refuse landfill comprises a sealing adsorption subsystem 18 and at least one middle adsorption subsystem 19. The sealing adsorption subsystem 18 comprises six functional layers which are sequentially from top to bottom: vegetation layer 2, drainage blanket 3, barrier layer 4, drainage layer 5, odor adsorption layer I6, gas collection layer I7, be the rubbish body under the gas collection layer I7. The middle adsorption subsystem 19 of the refuse landfill comprises three functional layers which are sequentially from top to bottom: an upper gas collecting layer 10, an odor adsorption layer II, a lower gas collecting layer 12, and garbage under the gas collecting layer 12.

The functional materials of the sealing adsorption subsystem 18 are as follows: the vegetation layer 2 soil needs to meet the relevant requirements of the vegetation layer soil of the refuse landfill, and the utility model does not have additional limitation requirements. If the vegetation layer 2 is prepared by natural soil and surface layer nutrient soil, the soil around a landfill can also be adopted. The drainage layer 3, the impermeable layer 4, the guide and exhaust layer 5, the odor adsorption layer I6 and the air collection layer I7 are all constructed by adopting recycled materials prepared by recycling construction wastes buried in a refuse landfill site, and are preferably prepared by using waste high-strength concrete. The strength of the original concrete of the drainage layer 3, the impervious layer 4, the drainage layer 5 and the air collecting layer I7 is not lower than C10, and the strength of the original concrete of the odor adsorption layer I material is not lower than C30; and before the construction waste is used for preparing the recycled aggregate, impurities (including slag, steel bars, wood, glass, plastics, bricks, paper, fabrics and the like) are removed, only concrete and mortar blocks are reserved, and the weight ratio of the concrete to the mortar is not less than 95%.

In the sealing adsorption subsystem 18, the vegetable layer 2 is natural soil plus surface nutrient soil or peripheral soil of the landfill, the thickness is determined according to the depth of the planted plant root system, the thickness is not less than 0.5m, the vegetable layer soil is compacted in a layering manner, and the compaction degree is not less than 80%. The vegetation layer preferably plants turf with shallow root systems, and fertilizing, irrigating, plowing construction methods and the like of the vegetation layer soil are determined according to the characteristics of the planted plants. The vegetation layer mainly has the functions of greening and beautifying, preventing water and soil loss, and releasing water infiltrated and stored in the vegetation layer to the atmospheric environment through surface evaporation and plant transpiration in non-rainfall time so as to keep the water balance of the sealing adsorption subsystem. It should be noted that the vegetable layer in the present invention mainly functions as described above, and does not take on the functions of preventing the permeation of gas and adsorbing odor. Therefore, the main consideration factors for the parameter design of the vegetation layer 2 are nearby materials, enough soil nutrition to support the growth of the vegetation 1 in the landfill, low material cost and the like.

The sealing adsorption subsystem 18 is characterized in that the drainage layer 3 is positioned below the vegetation layer 2 and above the impermeable layer 4, and is constructed by recycled coarse aggregate prepared by recycling construction waste buried in a refuse landfill, the thickness is 0.2-0.4m, the particle size is 20-40mm, the compacted relative density is not lower than 0.9, and the permeability coefficient is not lower than 10^-1m/s. The main function of the drainage layer is to conduct away the water infiltrated into the drainage layer and to serve as a support layer for the vegetation layer. Therefore, the main requirements for the parameter performance are that the mechanical strength is good enough to support the vegetable layer, the permeability is good so as to drain the water seeping under the vegetable layer as fast as possible, the material is convenient to obtain, the material cost is low, the durability is good, and the like. The parameter design of the drainage layer needs to consider factors such as local maximum rainfall, maximum infiltration of the vegetation layer, gradient, permeability coefficient of the drainage layer, thickness of the drainage layer and the like so as to meet the maximum drainage requirement. In addition, the strength of the recycled aggregate of the construction waste is far higher than the mechanical property of natural soil, so that the requirement of the mechanical strength of the supporting vegetable layer can be met.

The sealing adsorption subsystem 18 and the impermeable layer 4 are positioned between the drainage layer 3 and the drainage guide layer 5, the raw material of the impermeable layer 4 is recycled fine aggregate prepared by recycling construction waste buried in a refuse landfill, the maximum particle size of the recycled fine aggregate is 2mm, and the effective particle size d of a particle size grading curve₁₀Not more than 0.01mm, coefficient of non-uniformity C_UNot less than 5, coefficient of curvature C_CBetween 1 and 3, i.e. 3. gtoreq.C_CNot less than 1, not less than 95% of compactness and 10 of permeability coefficient^-9m/s -10^-6m/s, the water absorption is more than or equal to 8 percent, and the unsaturated soil mechanical air inlet value is more than or equal to 5 kPa; the raw material of the guide and discharge layer is recycled and prepared recycled coarse aggregate from construction waste buried in a waste landfill site; the thickness of the guide and drainage layer is 0.2-0.4m, the particle size is 10-40mm, the compacted relative density is more than or equal to 0.9, and the unsaturated soil mechanical air inlet value exceeds 1 kPa; the difference value of the air inlet values between the recycled fine aggregate of the impermeable layer and the recycled coarse aggregate of the guide and discharge layer is more than or equal to 4 kPa.

The functions of the impermeable layer 4 mainly comprise surface drainage, water storage, seepage prevention, moisture preservation, gas collection and odor adsorption. Firstly, the compaction degree of the compacted recycled aggregate of the impervious layer is controlled to be more than 95 percent, and the permeability coefficient is not more than 10^-6m/s, and the slope design of the sealing adsorption subsystem (the slope of the utility model can be 30-60 degrees, preferably 40-50 degrees), can effectively reduce rainwater infiltration, and convert most rainwater into drainage layer lateral guide and drainage 22. Secondly, the compacted recycled aggregate of the impermeable layer has good water storage and water retention capacity, and can absorb and store infiltration water to the maximum extent in rainfall. On the other hand, the difference of the air inlet values between the recycled fine aggregate of the impermeable layer and the recycled coarse aggregate of the drainage guide layer is more than 4KPa, so that a capillary blocking covering layer is formed, a capillary blocking effect is formed, and the infiltration water can be effectively blocked from entering the drainage guide layer. The moisture retention function of the impermeable layer refers to that the capillary retardation covering layer formed by the impermeable layer and the drainage guide layer can effectively protect the following odor adsorption layer I, prevent the odor adsorption layer I from evaporating and airing, be beneficial to maintaining the odor adsorption layer I at a higher water content for a long time, and compact and recycle fine aggregate and H in the environment with a higher water content₂The adsorption reaction of S is accelerated, and the odor adsorption reaction of the odor adsorption layer I can be better promoted and guaranteed. The gas collection function of the impermeable layer refers to the odor (mainly H)₂S) when the odor adsorption layer I fails to perform adsorption reaction and breaks through the odor adsorption layer I to enter the drainage guide layer, the permeability coefficient of the impermeable layer is lower, so that further upward breaking through and overflowing of odor can be effectively preventedThe odor which breaks through the odor adsorption layer I is accumulated in the guide exhaust layer to form a gas collection effect, and the higher air pressure and the higher concentration H in the guide exhaust layer are maintained₂S gas, which accelerates the recovery of aggregate and H in the odor adsorption layer I₂Chemical reaction of S gas to accelerate H₂S is adsorbed; in the case of evacuation, the gas collection layer and the gas guide and discharge layer H can also be helped₂The enrichment of the S gas has a favorable effect on odor adsorption. The odor adsorption function of the impermeable layer means that the construction material of the impermeable layer is the recycled fine aggregate of construction waste, and unreacted quicklime (CaO) or hydrated lime (Ca (OH) remains inside₂) When alkaline substances are used, the odor (mainly H) overflowing upwards from the odor adsorption layer I can be broken through₂S) an adsorption reaction is carried out, so that the odor is prevented from further overflowing the sealing adsorption subsystem to enter the atmospheric environment to influence the surrounding environment.

The sealing adsorption subsystem 18 and the guide and exhaust layer 5 are positioned between the impermeable layer 4 and the odor adsorption layer I6 and are constructed by adopting regenerated coarse aggregate prepared by recycling construction waste buried in a refuse landfill. The thickness of the drainage guide layer is 0.2-0.4m, the grain diameter is 10-40mm, the preferable grain diameter is 20-40mm, the compaction relative density is not less than 0.9, and the unsaturated soil mechanical air intake value is not more than 1 KPa. The drainage layer mainly has the functions of seepage prevention, drainage and gas collection. The seepage-proofing and drainage function is that a capillary blocking covering layer is formed between the regenerated coarse aggregate of the guide and drainage layer and the regenerated fine aggregate of the seepage-proofing layer to prevent the infiltrated rainwater from further entering the guide and drainage layer, the odor adsorption layer I and even the garbage body; after the infiltration water breaks through the capillary retardation effect, the permeability coefficient of the drainage and guide layer is larger (not less than 10)^-2m/s) can laterally guide and drain the moisture permeating into the drainage layer. On the other hand, a high-permeability odor enrichment area is formed under the impermeable layer, so that gases (including H) breaking through the odor adsorption layer I can be collected conveniently₂S) to provide certain gas collection and exhaust functions, and facilitate control of H with higher gas pressure and higher concentration in the gas guide and exhaust layer₂S gas, which accelerates the recovery of aggregate and H in the odor adsorption layer I₂Chemical reaction of S gas to accelerate H₂And (4) adsorbing S.

The raw material of the odor adsorption layer I6 is a regenerated fine material, and is prepared by blending regenerated fine aggregate prepared by recycling construction waste and regenerated powder, and the parameters are as follows:

(1) the material requirements are as follows: the recycled aggregate needs to be subjected to material quality control, wherein the recycled fine material comprises recycled fine aggregate and recycled powder, preferably recycled aggregate prepared by waste high-strength concrete, and the strength of the original concrete is required to be not lower than C30; and before the construction waste is used for preparing the recycled aggregate, impurities (including muck, steel bars, wood, glass, plastics, bricks, paper, fabrics and the like) are removed, only concrete and mortar blocks are reserved, the weight ratio of the concrete to the mortar is not less than 95%, and the content of the set cement (and a cement paste hardened body) and the mortar is not less than 40%. The grade of original concrete is increased, the proportion of cement in corresponding proportion is increased, and the residual quicklime (CaO) or hydrated lime (Ca (OH) in the original concrete₂) The more alkaline substances, the more favorable the odor adsorption capacity is.

(2) Layer thickness: the thickness is 0.4-1.0 m. It should be noted that the thickness of the odor adsorption layer i depends on the thickness of the landfill work and the type of landfill, and the adsorption characteristics of the adsorption material in the odor adsorption layer i. When the landfill thickness is increased and the content of sulfur-containing organic waste in which H2S can be produced by degradation is increased, it means that H2S to be produced from the landfill is also increased and the thickness of the corresponding odor adsorbing layer i is also increased.

(3) The particle size distribution curve shows a saddle shape, namely, the proportion of fine particle size and coarse particle size is larger, and the number of intermediate particles is relatively small. Specifically, according to the soil mechanics standard, the particle size grading curve characteristics of the recycled fines need to satisfy the following conditions: (a) the maximum grain size is not more than 2 mm; (b) effective particle diameter d₁₀Not more than 0.005 mm; (c) d is not less than 1.2mm₉₀Less than or equal to 1.8 mm; (d) the non-uniformity coefficient CU is more than or equal to 5; (e) coefficient of curvature C_CBetween 1 and 3, i.e. 3. gtoreq.C_CNot less than 1. The particle size distribution is designed for the purpose of: the particle size distribution curve of the compacted fine aggregate layer presents a saddle shape, wherein, the shearing strength of coarse particles is higher, and the compacted fine aggregate layer is obtained after compactionThe framework of the obtained odor adsorption layer I6 improves the mechanical property of the odor adsorption layer I6 obtained after compaction. The fine-particle-size particles are filled in the skeleton pores constructed by the coarse-particle-size particles, the water holding capacity and the air permeability coefficient of the odor adsorption layer I6 obtained after compaction are controlled, and the water holding capacity and the air permeability coefficient of the odor adsorption layer I6 obtained after compaction can be improved and reduced due to the high proportion of the fine-particle-size particles.

(4) The compactness of the regenerated fine materials of the odor adsorption layer I is not less than 95%. The mechanical strength can be improved by improving the compactness, the pore volume is compressed, and the water holding capacity is improved; meanwhile, under the same thickness, the compaction degree is improved, and more recycled aggregates with more weight can be used, so that on one hand, the total amount of alkaline substances in the odor adsorption layer I can be increased, and the adsorption capacity is improved; on the other hand, more construction waste can be consumed, and the recycling of the construction waste is realized.

(5) The requirement of the regeneration fine material of the odor adsorption layer I on air permeability is as follows: the air permeability coefficient of the compacted regeneration fine material of the odor adsorption layer I under the maximum dry density is 10^-6m/s—10^-8m/s, inlet air value of 1 kPa-10 kPa. The purpose that the air permeability parameter was selected is according to the time that lies in controlling the foul smell and pass through odor adsorption layer I, and then reaches control foul smell throughput and prolongs the foul smell adsorption reaction time of foul smell in odor adsorption layer I, promotes the foul smell adsorption effect.

(6) The water absorption requirement is as follows: the water absorption rate of the odor adsorption layer I material is not less than 10%. The water absorption of recycled aggregate depends on the pore volume and the hydrophilic character of the material. Wherein the pores include pores among the particles of the compacted odor adsorption layer I and pores and fissures of the particles themselves. The porosity between particles depends on the shape, size, degree of compaction, etc. of the particles. Generally, the higher the contents of cement stones (i.e., cement paste hardened bodies) and mortar of the recycled fines, the greater the water absorption; the more microcracks in the fine aggregate, the greater the water absorption. The utility model requires that the proportion of concrete and mortar in the construction waste for preparing the recycled fine material is not less than 95 percent, and correspondingly, the requirement on the water absorption of the prepared recycled fine material is not less than 10 percent.

(7) The requirement of water content is as follows: the saturation is 60% -90%. The true bookThe pore water saturation with the new demand fines is not less than 60% because of H₂S adsorption reaction is comparatively suitable under humid environment, and the adsorption reaction that higher moisture content can promote takes place efficiency. However, in order to ensure the air permeability of the odor adsorption layer I, the pore water saturation of the compacted and regenerated fine material layer cannot be 100%, otherwise, the regenerated fine material layer is completely saturated, and the air permeability coefficient of the regenerated fine material layer is changed into 0. Through research, the utility model proposes that the maximum saturation is not higher than 90%. In order to ensure a saturation of 60% to 90%, this requires that the compacted and regenerated fines of the odor adsorption layer I contain enough fines (in particular agglomerates, i.e. agglomerates)<0.002 mm) to improve the water holding capacity of the odor adsorption layer I. In addition, the maintenance of the moisture content in the compacted and recycled aggregate of the odor adsorption layer I needs to be realized by processes of preparing the optimal moisture content by adding water before laying the regenerated fine materials, spraying water to the preset moisture content after laying, and the like.

The odor adsorption layer I of the sealing adsorption subsystem is mainly used for closing air and adsorbing odor and has an anti-seepage function, and the parameter design of the odor adsorption layer I also mainly aims at improving the odor adsorption capacity and efficiency to the greatest extent. The anti-seepage function of the odor adsorption layer I is mainly embodied in that the particles of the material of the odor adsorption layer I are much smaller than the regenerated coarse aggregate of the air collection layer, a capillary blocking effect can be formed between the particles of the material of the odor adsorption layer I and the regenerated coarse aggregate, and the water permeating into the odor adsorption layer I is prevented from further permeating into the air collection layer I and the garbage body. However, the moisture content of the odor adsorption layer i is maintained at a high level for a long period of time under the protection of the permeation-preventing layer and the drainage guide layer, and therefore, the water storage capacity of the odor adsorption layer i is relatively weak. Therefore, the anti-seepage function of the odor adsorption layer I is mainly shown in the capillary retardation effect between the odor adsorption layer I and the air collection layer. In addition, the adsorbing material air permeability coefficient of odor adsorption layer I is lower, can effectively prevent landfill gas to break through odor adsorption layer I and get into the atmosphere.

The odor adsorption action mechanism of the odor adsorption layer I is that construction waste recycled aggregate is used as an odor adsorption layer material, and unreacted quicklime (CaO) or hydrated lime (Ca (OH) remains in the construction waste₂) The alkaline substance and the acidic substance (mainly H) in the odor₂S) carrying out acid-base neutralization reaction. In order to generate and develop the chemical reaction, some environmental conditions, such as a large specific surface area to increase the reaction contact area, a humid environment, etc., are required. In the utility model, the theoretical adsorption capacity is controlled by controlling the material characteristics, the particle size distribution, the thickness of the adsorption layer and the like of the odor adsorption layer I, and the adsorption effect is further controlled by controlling the contact area between odor and an adsorption material, the water content of the odor adsorption layer I, the odor passing amount, the odor passing rate, the odor passing time (namely, the odor adsorption reaction time) and the like by controlling the compactness, the fine particle ratio and the like.

The anti-seepage function of the odor adsorption layer I is mainly embodied in that the materials of the odor adsorption layer I and the regenerated coarse aggregate of the air collection layer I have particle size difference, a capillary blocking effect can be formed between the materials of the odor adsorption layer I and the regenerated coarse aggregate, and the water permeating into the odor adsorption layer I is prevented from further permeating into the air collection layer I and garbage. However, the moisture content of the odor adsorption layer i is maintained at a high level for a long period of time under the protection of the permeation-preventing layer and the drainage guide layer, and therefore, the water storage capacity of the odor adsorption layer i is relatively weak. Therefore, the anti-seepage function of the odor adsorption layer I is mainly shown in the capillary retardation effect between the odor adsorption layer I and the air collection layer I. However, in general, the anti-seepage function of the adsorption subsystem related by the utility model is mainly realized by the anti-seepage layer, and the anti-seepage function of the odor adsorption layer I is taken as an auxiliary function.

The sealing adsorption subsystem 18 is characterized in that the gas collection layer I is constructed by recycled coarse aggregate, the thickness is 0.3-0.5m, the particle size is 20-40mm, and the compacted relative density is not lower than 0.9. The gas collecting layer I is used for collecting odor conveniently between the odor adsorption layer I and a garbage body and controlling H in the gas collecting layer through the air exhaust device₂The intensity of the partial pressure of S gas, and further H is controlled₂And distributing the partial pressure of the S gas in the closed field adsorption subsystem. After the odor generated by the degradation of the garbage body enters the seal adsorption subsystem, the odor is separated by the odor adsorption layer I and the impermeable layer and is enriched in the seal adsorption subsystem. The gas collecting layer I has larger particle size and higher pore volume, and can enrich a large amount of gas; and the air permeability coefficient of the air collecting layer I is larger, so that the air collecting layer I can be used for exhausting airThe odor is quickly pumped away and discharged, and the vertical distribution of the odor partial pressure in the adsorption subsystem is convenient to control. In addition, a capillary retardation effect can be formed between the regenerated coarse aggregate of the air collecting layer I and the adsorbing material of the odor adsorption layer, an anti-seepage function can be provided in an auxiliary mode, and moisture permeating into the odor adsorption layer I is prevented from further permeating into the air collecting layer I and the garbage body.

The sealing adsorption subsystem 18, the compacted regenerated fine aggregate layer of the impermeable layer 4 and the water storage of the regenerated fine aggregate layer of the odor adsorption layer I are mainly realized through large pore accommodation, capillary pore holding and fine particle adsorption. The larger the mass fraction of the clay particles is, the more the capillary content is, the more the storage pores are, the larger the specific surface area is, the stronger the adsorption capacity is, and the stronger the water holding capacity is. And the volume water content of the soil of each water absorption section is gradually reduced along with the increase of the mass fraction of the sticky particles in a soil-water characteristic curve. In the middle-low water absorption section, the larger the mass fraction of clay particles is, the more the capillary content is, the stronger the capillary absorption capacity is, and the more water is held; in the high water absorption section, the huge surface area and surface charge of the clay particles enable the clay particles to have extremely strong water molecule adsorption capacity, a thick water adsorption layer or water film is formed, pores among the clay particles are extremely fine, a thick water adsorption layer or water film is formed, the pores among the clay particles are extremely fine, a certain amount of water can be kept outside the water adsorption film under the action of capillary force, and the stronger the mass fraction of the clay particles is, the stronger the effect is.

The design of the grain size grading of the material of the sealing adsorption subsystem 18 and the odor adsorption layer I also aims to increase the proportion of fine grains, further increase the adsorption material in the material of the odor adsorption layer I and improve the odor adsorption capacity; the total specific surface area of the material of the odor adsorption layer I is increased, so that the contact area with odor is increased, and the odor adsorption efficiency and capability are improved; through the proportion that increases the granule, can effectively strengthen the water holding capacity of odor adsorption layer I, reduce the gas permeability coefficient, and then control unit interval and pass through the odor volume of odor adsorption layer I and prolong the foul smell transit time, and then reach the foul smell adsorption reaction time of extension foul smell in odor adsorption layer I, promote the foul smell adsorption effect. The parameter design of the odor adsorption layer II of the middle adsorption subsystem is the same.

The field-closing adsorption subsystem 18, whose external cross-section is trapezoidal as in fig. 1, includes a plane and an inclined slope, and if the external cross-section is triangular, only includes an inclined slope.

In the sealing adsorption subsystem 18, the vegetation layer 2 comprises soil capable of cultivating the vegetation 1, the thickness of the vegetation layer 2 meets the requirement of the root system of the planted vegetation 1, and the thickness of the vegetation layer 2 is more than or equal to 0.5 m; the drainage layer 3 is made of recycled coarse aggregate prepared by recycling construction waste buried in a refuse landfill, the thickness is 0.2-0.4m, the particle size is 20-40mm, and the compaction relative density is more than or equal to 0.9; water-permeable and air-permeable isolating material layers 9 for preventing raw materials of each layer from being mixed are arranged among the layers for spacing; the original concrete strength of the materials of the odor adsorption layer I and the odor adsorption layer II is not lower than C30, and the original concrete strength of the other layers except the vegetation layer is not lower than C10. The water-permeable and air-permeable insulating material layer 9 is geotextile.

The preparation method of the sealing adsorption subsystem 18 comprises the following steps: (1) preparing materials according to the raw material requirements of each functional layer; before preparing the recycled aggregate and the recycled powder, impurities such as wood, steel bars, muck and the like in the construction waste are removed through pretreatment, and only the waste concrete and the mortar stone are reserved; (2) and laying each functional layer according to the requirements of each layer.

The middle adsorption subsystem 19 comprises three functional layers, namely an upper gas collecting layer 10, an odor adsorption layer II 11 and a lower gas collecting layer 12 of the middle adsorption subsystem from top to bottom in sequence.

The middle adsorption subsystem 19, the upper air collecting layer 10, the odor adsorption layer II 11 and the lower air collecting layer 12 are all constructed by adopting recycled materials prepared by recycling construction wastes buried in a refuse landfill, and are preferably prepared by using waste high-strength concrete. The strength of the original concrete of the upper air collecting layer and the lower air collecting layer is not lower than C10, and the strength of the original concrete of the odor adsorption layer II material of the middle adsorption subsystem is not lower than C30; and before the construction waste is used for preparing the recycled aggregate, impurities (including slag, steel bars, wood, glass, plastics, bricks, paper, fabrics and the like) are removed, only concrete and mortar blocks are reserved, and the weight ratio of the concrete to the mortar is not less than 95%.

The middle adsorption subsystem 19 and the upper gas collecting layer 10 are constructed by recycled coarse aggregate, the thickness is 0.2-0.4m, the particle size is 20-40mm, and the compacted relative density is not lower than 0.9. The function of the gas collecting layer on the middle adsorption subsystem is to isolate the odor adsorption layer II of the middle adsorption subsystem from the garbage body on the odor adsorption layer II so as to avoid direct contact between the odor adsorption layer II and the garbage body; a gas collecting layer with high permeability is formed between the odor adsorption layer II of the middle adsorption subsystem and the garbage body on the odor adsorption layer II, so that H is facilitated₂S gas overflows downwards from the garbage body above the odor adsorption layer II and is enriched in the upper gas collection layer; h is controlled under the control of the upper gas collecting layer air extractor 15₂The partial pressure value of S gas in the upper gas collecting layer is controlled to further control H₂The partial pressure distribution of the S gas in the odor adsorption layer II of the middle adsorption subsystem influences the progress of odor adsorption reaction.

The odor adsorption layer II of the middle adsorption subsystem 19 adopts regenerated fine materials prepared by mixing regenerated fine aggregate prepared by recycling construction waste and regenerated powder, the thickness of the odor adsorption layer II is 0.3-0.6m, and the performance parameters of other materials are the same as the requirements of the odor adsorption layer of the sealing adsorption subsystem. The odor adsorption layer II of the intermediate adsorption subsystem is used for temporary odor adsorption when the intermediate adsorption subsystem is used, and can be used as an intermediate layer of the garbage body for continuously adsorbing odor after the closing of the field.

The lower gas collecting layer 12 of the middle adsorption subsystem 19 is constructed by regenerated coarse aggregate, the thickness is 0.2-0.4m, the particle size is 20-40mm, and the compacted relative density is not lower than 0.9. The lower gas collecting layer of the middle adsorption subsystem is used for isolating the odor adsorption layer II of the middle adsorption subsystem from the garbage body below the odor adsorption layer II so as to prevent the odor adsorption layer II and the garbage body from directly contacting; a gas collecting layer with high permeability is formed between the odor adsorption layer II of the middle adsorption subsystem and the garbage below the odor adsorption layer II, so that H is facilitated₂S gas overflows upwards from the garbage below the odor adsorption layer II and is enriched in the lower gas collection layer; under the control of the lower gas collecting layer air extractor 16, H is controlled₂The partial pressure value of S gas in the lower gas collecting layer is controlled to further control H₂S gasThe distribution of the partial air pressure of the body in the odor adsorption layer II of the middle adsorption subsystem influences the progress of odor adsorption reaction.

Bottom impermeable linings are further arranged below and on the side part of the lowermost garbage body, so that the odor adsorption system, the garbage body and the bottom impermeable lining in the prior art form a bottom impermeable lining, a garbage body, an intermediate adsorption subsystem, … …, a garbage body and a sealing adsorption subsystem, and the bottom impermeable lining is an impermeable lining layer 17. In the structure body formed by staggered superposition of the composite structure of the garbage body and the middle adsorption subsystem, the middle adsorption subsystem is fully contacted with the garbage body 8, namely, the odor adsorption layer II of the middle adsorption subsystem is mixed in the garbage, and multi-level adsorption is realized. The intermediate adsorption subsystem is used for temporary odor adsorption during the landfill operation, and is used as an intermediate layer of the garbage body 8 for continuous odor adsorption after the landfill is closed.

The odor adsorption system of the refuse landfill is characterized in that the side part of the gas collection layer is provided with a gas collection layer air extractor. The gas collecting layer air extracting device is the gas collecting layer I air extracting device 14, the upper gas collecting layer air extracting device 15 or the lower gas collecting layer air extracting device 16.

And water-permeable and air-permeable insulating material layers 9 are arranged between all functional layers of the sealing adsorption subsystem and the middle adsorption subsystem and between the functional layers and the garbage body, and the insulating material layers 9 are preferably made of geotextile. Because the particle size difference of particles among all functional layers is large, the geotextile is laid in advance to prevent the materials with small particles from falling into the materials with large particles, and the mutual mixing condition can be prevented. In addition, geotextile may be laid between the gas collection layer I and the garbage body to prevent mutual mixing.

The water storage of the impermeable layer and the odor adsorption layer I is mainly realized through the large pore accommodation, capillary pore adsorption and fine aggregate particle adsorption. The larger the clay mass fraction of the soil is, the more the capillary content is, the more the storage pores are, the larger the specific surface area is, the stronger the adsorption capacity is, and the stronger the water holding capacity is. And the volume water content of the soil of each water absorption section is gradually reduced along with the increase of the mass fraction of the sticky particles in a soil-water characteristic curve. In the middle-low water absorption section, the larger the mass fraction of clay particles is, the more the capillary content is, the stronger the capillary absorption capacity is, and the more water is held; in the high water absorption section, the huge surface area and surface charge of the clay grains enable the clay grains to have extremely strong capacity of absorbing water molecules, a thick water absorption layer or water film is formed, pores among the clay grains are extremely fine, a thick water absorption layer or water film is formed, the pores among the clay grains are extremely fine, a certain amount of water can be kept outside the water absorption film under the action of capillary force, and the stronger the mass fraction of the clay grains is, the stronger the effect is.

The action mechanism of the odor adsorption system of the refuse landfill related by the utility model is as follows:

the core functions of the landfill odor adsorption system comprise an anti-seepage air-blocking function and an H function unique to the utility model₂S odor adsorption function. Wherein, the anti-seepage air-lock function is realized by the sealing adsorption subsystem.

FIG. 7 is a schematic view of the anti-seepage air-lock principle of the present invention. The anti-seepage function is mainly realized by a double capillary retarding covering layer formed by a sealing adsorption subsystem, namely, the anti-seepage layer and the drainage layer form a first heavy capillary retarding covering layer, and a second heavy capillary retarding covering layer which is positioned right below the first heavy capillary retarding covering layer and is formed by an odor adsorption layer I and a gas collection layer I, wherein the anti-seepage function of the first heavy capillary retarding covering layer is mainly used, and the second heavy capillary retarding covering layer is used as an auxiliary function. The anti-seepage working mechanism of the double capillary retardation covering layer is as follows:

during rainfall 20, most of rainwater can form slope runoff 21 to be guided and drained along the slope, and then enter a rainwater collecting and guiding system of a landfill site, and a small amount of rainwater infiltrates into a vegetation layer 2. Rainwater entering the vegetable layer is stored in the vegetable layer, and when the storage capacity of the vegetable layer is exceeded, rainwater penetrating into the vegetable layer 2 can be stored in soil pores of the vegetable layer 2 on the one hand, and the other part of rainwater continuously seeps into the drainage layer 3. The water drainage layer 3 has a large saturation permeability coefficient, the permeability coefficient of the impermeable layer 4 is small, most of the water entering the water drainage layer can be drained in the middle of the water drainage layer 3 in a lateral direction (namely the water drainage layer lateral guide and drainage 22), and a small amount of water can penetrate into the impermeable layer 4.

A part of the moisture permeating into the barrier layer 4 is stored in the pores of the barrier layer 4, and another part of the moisture continues to permeate down to the interface between the barrier layer 4 and the drainage guide layer. This interface will cause capillary retardation due to the difference in particle size and air intake of the upper and lower layers. At this time, under the action of the capillary retardation effect, the water permeating into the impermeable layer cannot continuously permeate downwards, and under the action of the slope, the water is guided and drained downwards along the boundary surface between the impermeable layer 4 and the drainage guide layer 5. As the water stored in the impermeable layer increases, the suction force of the impermeable layer is reduced, and the capillary blocking effect between the impermeable layer 4 and the drainage guide layer 5 is weakened or even disappears until the infiltrated water breaks through the capillary blocking covering layer. At this point, the first heavy capillary retarding coating layer fails and the ingress of water begins to enter drainage layer 5. The second, re-wicking barrier coating then comes into play. Most of the water permeating into the drainage guide layer 5 is guided and drained down the slope in the drainage guide layer 5 (i.e. the drainage guide layer 23 is laterally guided and drained), and a small amount of water permeates into the odor adsorption layer I. Because the protection of the first heavy capillary retardation covering layer formed by the impermeable layer and the drainage guide layer, the odor adsorption layer I is maintained in a high water content state for a long time, and therefore, the water storage capacity of the odor adsorption layer I is weaker. At this time, the barrier function of the second heavy capillary-retarding coating layer mainly depends on the capillary-retarding effect of the interface between the odor adsorbing layer I and the air collecting layer I. Under the action of the retardation effect, moisture entering the odor adsorption layer I is prevented from being on the interface of the odor adsorption layer I and the air collection layer I and is guided and discharged along the interface. Under the combined action of the double capillary retarding covering layers, rainwater can be effectively prevented from infiltrating into the garbage to form percolate.

During the time of no rainfall, the moisture stored in the vegetation layer and the impervious layer can be released to the atmosphere through the evaporation of the ground surface and the transpiration of the vegetation layer plants.

Therefore, through water storage/drainage guide during rainfall and evaporation and transpiration release during non-rainfall time, the enclosure adsorption subsystem related by the utility model realizes water balance in the weather dry-wet cycle.

In addition, under the protection of the first heavy capillary resistance covering layer formed by the impermeable layer and the drainage guide layer, the second heavy capillary resistance covering layer can keep higher water content. And under higher moisture content, the gas permeability coefficient of odor adsorption layer I is relatively lower, can effectively prevent the odor from overflowing to the atmosphere, thereby realize the function of closing the gas.

Figures 5 and 6 are schematic diagrams of the odor adsorption principle of the present invention. H relating to the utility model₂The odor adsorption function is realized mainly by the layer-by-layer adsorption of the intermediate adsorption subsystems constructed during the step-by-step landfill and the final adsorption of the closing adsorption subsystem, namely the odor adsorption is realized by a combined adsorption system consisting of a plurality of intermediate adsorption subsystems and the final closing adsorption subsystem.

The odor adsorption principle of the middle adsorption subsystem is as follows: the odor adsorption in the middle adsorption subsystem 19 is mainly realized by the adsorption reaction of the upper gas collecting layer 10, the lower gas collecting layer 12 and the odor adsorption layer II 11. The upper gas collecting layer and the lower gas collecting layer have larger particle size, higher pore volume and larger gas permeability coefficient, can collect landfill gas generated by the upper garbage body and the lower garbage body, and enrich and maintain higher H in the upper gas collecting layer and the lower gas collecting layer₂S partial pressure, i.e. the upper and lower odor adsorption layers II of the middle adsorption subsystem are at higher H₂In the environment of S partial pressure, the recovery aggregate and H in the odor adsorption layer II of the middle adsorption subsystem can be accelerated₂Chemical reaction of S gas to accelerate H₂And (4) adsorbing S. In addition, the upper air collecting layer and the lower air collecting layer are respectively provided with an air exhaust device for controlling the air pressure of the upper air collecting layer and the lower air collecting layer, especially H₂The partial pressure of the S gas is controlled, so that the H in the odor adsorption layer II is controlled₂The distribution of the partial pressure of the S gas along with the depth is convenient to achieve the best odor adsorption effect.

As shown in figure 6, the utility model needs a plurality of intermediate adsorption subsystems, and the intermediate adsorption subsystem with the serial number N is selected as an illustration in figure 6. In the intermediate adsorption subsystem with the serial number N: the contact depth of the upper gas collecting layer and the garbage body is D_N0The contact depth of the upper air collecting layer and the odor adsorption layer II 11 is D_N1Lower air collecting layer and odor adsorption layer II11 contact depth D_N2The contact depth of the lower gas collecting layer and the garbage body is D_N3H of upper and lower gas collecting layers₂The partial pressure of S gas can be regarded as P_N2The burying depth of the longitudinal middle thickness of the odor adsorption layer II is D_NCBuried depth of D_NCOf (a) H₂Partial pressure of S gas is P_N1. From D in odor adsorption layer_NCTo D_N1And D_NCTo D_N2H of (A) to (B)₂S gas partial pressure appears along the longitudinal direction along with the depth from P_N1To P_N2Is linearly distributed.

Normally, H for the odor adsorption layer II of the intermediate adsorption subsystem₂S gas partial pressure P_N1The control value of (B) is between 0kPa and 2kPa, and the optimum control value is 0 kPa. H of upper and lower gas collecting layers of middle adsorption subsystem₂Partial pressure P of S gas_N1The control value of (A) is between 0kPa and 10kPa, and H in the middle adsorption subsystem is ensured₂S gas partial pressure P_N1And P_N2Under the condition of not exceeding the standard, the middle adsorption subsystem H is properly increased₂Partial pressure P of S gas_N1And P_N2The odor adsorption reaction generation efficiency and the adsorption effect can be effectively improved. H in the upper and lower gas collecting layers is controlled by an upper gas collecting layer air exhaust device 15 and a lower gas collecting layer air exhaust device 16₂Partial pressure P of S gas_N2Value, and further control of H in odor adsorbing layer II₂The distribution of the partial pressure of the S gas along with the depth is convenient to achieve the best odor adsorption effect.

The middle adsorption subsystem, the garbage body and the bottom impermeable lining in the prior art form a bottom impermeable lining-garbage-middle adsorption subsystem- … … -garbage-closing adsorption subsystem. In the structure body formed by staggered superposition of the composite structure of the garbage-intermediate adsorption subsystem, the intermediate adsorption subsystem is fully contacted with garbage, namely an odor adsorption layer II of the intermediate adsorption subsystem is mixed in the garbage, and multi-level adsorption is realized. The intermediate adsorption subsystem can be used for temporary odor adsorption when being used as the intermediate adsorption subsystem on one hand, and can be used as an intermediate layer of the garbage body for continuing odor adsorption after being shut down on the other hand.

The odor adsorption principle of the sealing adsorption subsystem 18 is as follows: odor adsorption in the closed adsorption subsystem is mainly realized through the air-tight layer 4, the gas collection of the guide and exhaust layer 5 and the gas collection layer I7 and the adsorption reaction of the odor adsorption layer I6. The gas-blocking function of the barrier layer helps to maintain a higher gas pressure and a higher concentration of H therebelow₂S gas, which accelerates the recovery of aggregate and H in the odor adsorption layer I₂Chemical reaction of S gas to accelerate H₂S is adsorbed; the particle diameter of the guide and exhaust layer and the gas collection layer I is larger, the pore volume is higher, the gas permeability coefficient is larger, and a large amount of gas can be enriched. In addition, the air-blocking function of the odor adsorption layer I6 helps to maintain a higher air pressure and a higher concentration of H in the air collection layer 7₂S gas, which accelerates the recovery of aggregate and H in the odor adsorbing layer I6₂Chemical reaction of S gas to accelerate H₂And (4) adsorbing S. In addition, the gas collection layer I and the gas guide layer I are respectively provided with an air exhaust device, namely a gas guide layer air exhaust device 13 and an air exhaust device 14 of the gas collection layer I, and the air exhaust devices are used for controlling the air pressure of the odor adsorption layer I and the gas collection layer I, especially the air pressure of H₂The partial pressure of S gas is controlled to further control H in the odor adsorption layer I₂The distribution of the partial pressure of the S gas along with the depth is convenient to achieve the best odor adsorption effect.

According to the basic theory of soil mechanics, the particles of the drainage layer 3, the drainage layer 5 and the gas collection layer 7 are large, the gas permeability is good, and the gas pressure in the drainage layer can be regarded as equal everywhere. As shown in fig. 5, H of the drainage layer 5 and the gas collection layer 7₂The partial pressure of S gas is P₁And P₂H in odor adsorption layer I6₂The partial pressure of S gas is represented from P with vertical depth₁To P₂Is linearly distributed. In FIG. 5, the buried depth of the surface of the vegetation layer 2 is D₀The surface burial depth of the drainage layer 3, namely the burial depth of the interface between the vegetation layer 1 and the drainage layer 2 is D₁The surface burial depth of the impermeable layer 4, namely the burial depth of the interface of the drainage layer 3 and the impermeable layer 4 is D₂The surface burial depth of the guide and drainage layer 5, namely the burial depth of the interface between the impermeable layer 4 and the guide and drainage layer 5 is D₃The odor adsorption layer I6 is buried deep on the surface to form the drainage layer 5 and the odorThe buried depth of the interface of the gas adsorption layer I6 is D₄The surface burial depth of the gas collection layer 7, namely the burial depth of the interface between the odor adsorption layer I6 and the gas collection layer 7 is D₅，H₂The critical depth of the partial pressure of S gas is 0kPa and D_T，D_TBetween D₂And D₃In the meantime. And the vegetation layer 2, the drainage layer 3 and the impermeable layer 4 are arranged from the surface D₂To a depth D_TH of (A) to (B)₂The partial pressure of S gas was 0kPa from depth D_TTo D₃Exhibit a vertical dimension of from 0kPa to P₁Is linearly distributed.

In the embodiment of the utility model, the air extracting device of the air collecting layer I can control the H of the air collecting layer by extracting and exhausting air₂Partial pressure P of S gas₂The exhaust device of the guide and exhaust layer can control the H of the guide and exhaust layer 5 by exhausting air₂Partial pressure P of S gas₁. In general, H for the conducting and draining layers₂S gas partial pressure P₁The control value of (B) is between 0kPa and 1 kPa. H of gas-collecting layer I₂Partial pressure P of S gas₂The control value of (A) is between 0kPa and 10kPa, and H of the drainage guide layer is ensured₂S gas partial pressure P₁Properly increasing the gas collecting layer IH under the condition of not exceeding the standard₂Partial pressure P of S gas₂The odor adsorption reaction generation efficiency and the adsorption effect can be effectively improved. H in the gas collecting layer I is controlled by the air exhaust device of the gas collecting layer I₂Partial pressure P of S gas₂The value is obtained.

H in the whole sealing adsorption subsystem is controlled through the combined action of the exhaust device 13 of the guide exhaust layer and the exhaust device 14 of the air collecting layer I₂The distribution of the partial pressure of the S gas can achieve the best odor adsorption effect.

And the exhaust device 13 of the guide and exhaust layer can control D_TThe position of (a). When D is present_T=D₃=D₄When, H in the barrier layer 4 and the drainage layer 5 is illustrated₂The partial pressures of S gas were all 0kPa, i.e. no H was present₂The S gas overflows from the odor adsorption layer I. When D is present_T= D₁=D₂In time, H on the surface of the drainage layer and the impervious layer₂The partial pressure of S gas is 0kPa, and the critical state is reached, i.e. no H is generated₂S gas overflows from the impermeable layer and enters the vegetation layer to influence vegetation growth.

It should be noted that the exhaust guide layer 13, the exhaust device 14 of the gas collection layer i, the exhaust device 15 of the upper gas collection layer and the exhaust device 16 of the lower gas collection layer are not always installed or operated at full time, but are used as auxiliary facilities to ensure the H in the closed adsorption subsystem through exhaust and exhaust₂S, the distribution form of the partial pressure of the gas enables the enclosure adsorption subsystem to be in the optimal state of odor adsorption; while ensuring that no H is present₂The S gas overflows from the impermeable layer to pollute the atmosphere and the surrounding environment.

The odor adsorption material related by the utility model has the mechanism of odor adsorption action that: the construction waste recycled aggregate is used as the construction material of the odor adsorption layer, and unreacted quicklime (CaO) or hydrated lime (Ca (OH) remains in the construction waste₂) The alkaline substance and the acidic substance (mainly H) in the odor₂S) carrying out acid-base neutralization reaction, wherein the chemical reaction equation is as follows:

in addition, the high-strength concrete of the odor adsorption layer is prepared by crushing, and the characteristics of large thickness, high compactness, high fine particle proportion, high proportion of concrete and mortar blocks, high water content, moisture retention function of the impermeable layer and the like can effectively increase the theoretical adsorption capacity of the odor adsorption layer and create an environment suitable for adsorption reaction, thereby better improving the actual adsorption effect.

The manufacturing method of the adsorption system comprises the following steps:

(1) and (5) preparing materials.

The vegetation layer soil can be obtained nearby, the material requirement of the vegetation soil needs to meet the relevant specifications, and the method does not have special requirements.

The drainage layer, the impermeable layer, the guide and exhaust layer, the odor adsorption layer I, the air collection layer I and the regeneration materials required by the regeneration aggregate required by the middle adsorption subsystem of the sealing adsorption subsystem are prepared from waste building garbage, and preferably from building garbage buried in a garbage landfill. The preparation method comprises the following steps:

building garbage crushing station is set in the garbage burying field, the building garbage to be buried in the burying field is transported to the building garbage crushing station directly, and the regenerated coarse aggregate, the regenerated fine aggregate and the regenerated powder are prepared. Before the recycled aggregate is prepared, impurities such as wood, steel bars, muck and the like in the construction waste are removed through pretreatment, and only the waste concrete and the mortar stone are reserved. And then preparing the construction waste into recycled coarse aggregate, recycled fine aggregate and recycled powder through the working procedures of crushing, screening, impurity removing, grinding, drying, composite material selection and the like. The regeneration coarse aggregate and the regeneration fine aggregate which are required by corresponding preset particle size are prepared through the processes of crushing, grinding, sieving and the like, the micropowder is collected through dust collection equipment to prepare regeneration powder, and the regeneration powder and the regeneration fine aggregate are mixed together to prepare the regeneration fine material required by the odor adsorption layer. It should be noted that, in the production process of recycled aggregate at home and abroad, the recycled coarse aggregate and the recycled fine aggregate can be prepared by crushing and grading, and meanwhile, the dust collection equipment can collect micro powder (the particle size can be less than 0.15 mm) to prepare recycled powder.

Because the regenerated fine materials of the odor adsorption layer have requirements on the proportion of the micro-powder, the regenerated fine materials (namely the composite materials) required by the utility model can be prepared by mixing the regenerated fine aggregate and the regenerated powder according to a certain proportion in the actual industrial production process. The materials required by the seal adsorption subsystem and the intermediate adsorption subsystem need to meet the requirements.

The specific production and processing requirements of the reclaimed materials can refer to or be in accordance with the production specifications of construction engineering recycled aggregates (such as recycled coarse aggregates for GB/T25177-2010 concrete and DB 894.1-recycled sand powder application technical rules (Shanghai) and the like) so as to facilitate large-scale industrial production and reduce the process difficulty and the production cost.

It can be understood that the obtained recycled coarse aggregate, recycled fine aggregate and recycled powder can be used for constructing an odor adsorption system of a landfill on one hand and can also be used for other civil engineering construction on the other hand; similarly, the raw materials for constructing the closed-end adsorption subsystem can also be obtained from other landfills or other places where building garbage crushing stations are built.

(2) Adding water, mixing, and maintaining.

Before constructing the field-sealing adsorption subsystem and the middle adsorption subsystem respectively, required materials are required to be added with water respectively and mixed to be matched with the optimal water content, and then the materials are sealed and maintained so as to be uniform in water content. The optimal water content of each layer of material needs to be determined by experimental research in advance, and the determination method meets the requirements of relevant specifications of geotechnical tests (such as GBT 50123-2019 geotechnical test method standard). When the optimal water content is configured, the uniform water addition and the sufficient stirring are ensured, and the large agglomeration phenomenon is avoided. The material should be cured in a closed shade for 3-10 days.

(3) Laying an intermediate adsorption subsystem: the bottom impermeable lining is arranged below and on the side part of the lowest garbage body, the bottom impermeable lining-impermeable liner layer 17 is laid firstly (according to the prior art), and then the garbage is buried. After the garbage landfill operation of the garbage landfill site is finished, leveling and rolling are carried out to form a garbage body 8, and then a layer of geotextile is laid on the garbage body 8. And then laying the compacted coarse aggregate of the lower air-collecting layer on the geotextile, laying the regenerated coarse aggregate layer by layer and fully compacting, wherein the laying thickness of each layer is not too thick (generally not more than 10 cm), and the compaction degree needs to meet the requirement (not less than 0.9 relative density). And then laying geotextile. And then laying an odor adsorption layer II on the geotextile, laying in layers and fully compacting when laying, wherein the laying thickness of each layer is not more than 10cm, the compaction degree is not less than 95%, and scraping the surface of the previously compacted regenerated fine material layer when layering and compacting so that the front layer and the rear layer can be fully contacted and combined.

After the odor adsorption layer II is laid, manual watering or airing needs to be carried out on the odor adsorption layer II so that the water content of the odor adsorption layer II reaches the preset adsorption reaction water content. Generally, the odor adsorption layer II can play a role in seepage prevention and deodorization during temporary covering, and can also meet the requirements on seepage prevention, air tightness and deodorization in the landfill operation process. However, if the surrounding environment of the landfill site has higher requirements on seepage prevention, air closure and deodorization, a layer of geomembrane can be laid on the odor adsorption layer II to realize the seepage prevention and air closure functions at a higher level, and at the moment, the seepage prevention and air closure functions of the middle adsorption subsystem are mainly realized by the geomembrane. The laying, welding, maintenance and the like of the geomembrane are required to be carried out according to relevant specifications (such as GB/T50290-2014 geosynthetic material application technical specifications), and special requirements are not required in the utility model.

When the next round of garbage landfill operation is carried out, only the upper gas collecting layer is laid on the odor adsorption layer II, the laying method is the same as that of the lower gas collecting layer, the geotextile is laid firstly, then the upper gas collecting layer is laid on the geotextile, and then the garbage is filled. When the geomembrane is laid, the geomembrane needs to be firstly uncovered and detached, then an upper gas collecting layer is laid, and then a new round of landfill operation is carried out. The geomembrane can be continuously and repeatedly applied to the middle adsorption subsystem after the next round of landfill operation is finished, and the using method is the same.

And after the next round of refuse landfill operation is finished, continuing to lay the middle adsorption subsystem, then carrying out the next round of landfill operation until the preset landfill elevation is reached, sealing the field, and laying the sealing adsorption subsystem.

And after the middle adsorption subsystem is laid, monitoring and maintenance are required. Besides the monitoring of seepage-proofing drainage, percolate, garbage degradation, garbage body settlement and the like which are necessary for the traditional intermediate adsorption subsystem, the monitoring content also needs to be specially developed for the integrity and integrity of the intermediate adsorption subsystem and landfill gas (especially H)₂S), and the odor adsorption function operation condition of the intermediate adsorption subsystem.

(4) Laying an enclosure adsorption subsystem: after the garbage landfill operation of the garbage landfill site is finished, cleaning, leveling and rolling are carried out. Attention is paid to cleaning up sundries such as sharp stones, tree roots and the like, and all sundries need to be cleaned up. The base surface is not allowed to have local concave-convex phenomenon, and the cleaned base surface needs to be tamped by a tamping hammer or a tamping plate to be compact and flat.

Then, firstly, laying geotextile on the garbage body, then laying the compacted coarse aggregate of the gas collecting layer I on the geotextile, laying the regenerated coarse aggregate layer by layer and fully compacting, wherein the laying thickness of each layer is not too thick (generally not more than 10 cm), and the compaction degree needs to meet the requirement (not less than 0.9 relative density). Then, laying geotextile, then laying an odor adsorption layer I on the geotextile, laying in layers and fully compacting, wherein the laying thickness of each layer is not more than 10cm, the compaction degree is not less than 95%, and when in layered compaction, the surface of the previously compacted regenerated fine material layer is scraped, so that the front layer and the rear layer can be fully contacted and combined.

After the odor adsorption layer I is laid, manual watering or airing needs to be carried out on the odor adsorption layer I so that the water content of the odor adsorption layer I reaches the preset adsorption reaction water content.

And then laying geotextile, and then laying a guide layer on the geotextile, wherein the laying method and the requirements of the guide layer are the same as those of the gas collection layer I.

Then, laying geotextile, then laying an anti-seepage layer on the geotextile, laying layers and fully compacting, wherein the laying thickness of each layer is not more than 10cm, the compaction degree is not less than 95%, and when in layered compaction, the surface of the previously compacted regenerated fine aggregate layer is scraped, so that the front layer and the rear layer can be fully contacted and combined.

And then laying geotextile, and then laying a drainage layer on the geotextile, wherein the laying steps and requirements of the drainage layer are the same as those of the drainage layer. And then laying geotextile on the drainage layer.

Then laying geotextile, and then laying a vegetable layer on the geotextile. And (4) layering and compacting the soil materials in the vegetable layer, wherein the layer to layer needs to be scraped. And then carrying out greening planting on the vegetation layer. The fertilization, plowing construction, maintenance, irrigation and the like of the vegetation are executed according to relevant specifications, and the method does not make special requirements.

And after the completion of the laying of the sealing adsorption subsystem, monitoring and maintenance are required. The monitoring contents are except for the methods of seepage prevention, drainage, percolate, garbage degradation, garbage body settlement and the like which are necessary for the traditional sealing adsorption subsystemIn addition to area monitoring, there is a need to develop the integrity and integrity of the sequestration subsystem, and landfill gas (especially H) in particular₂S), and the running condition of the odor adsorption function of the sealing adsorption subsystem. In addition, maintenance of vegetation is also being carried out.

In the laying step, the geotextile laid between the functional layers mainly aims to prevent the granules of the upper and lower layers from being transferred due to large particle size difference and prevent the materials with small particles from falling into the materials with large particles to cause mutual mixing, and the geotextile requires water and air permeability and has strength meeting the requirement. The geotextile used by the method meets the basic performance requirement of the conventional geotextile used in the refuse landfill, and the method does not have special requirement.

In addition, compared with the operation characteristics of similar landfill sites, the operation characteristics of the landfill site where the odor adsorption system is located are that the odor adsorption system is operated for a small number of times, namely, the thickness of single landfill is reduced, and the total landfill operation times are increased; thus, the number of composite structures of 'garbage-middle adsorption subsystem-garbage' which are stacked up and down can be increased. The design concept is that the number of layers of the middle adsorption subsystems in the garbage body is increased as much as possible, and the total contact area of the odor adsorption layer and the garbage body is increased as much as possible, so that the odor adsorption capacity and the adsorption effect are improved.

The thickness of the single landfill operation, the corresponding thickness of the middle adsorption subsystem and the thickness of the sealing adsorption subsystem are calculated and demonstrated so as to be matched with each other. Generally, the increase of the thickness of a single landfill operation, the increase of the total amount of sulfur-containing organic matters in the single landfill, and the like inevitably leads to the odor H generated in the single landfill₂The theoretical amount of S increases, which inevitably results in an increase in the thickness of the odor adsorption layer ii in the intermediate adsorption subsystem required. In addition, the thickness of the odor adsorption layer is also related to the adsorption capacity of the odor adsorption layer material, and when the adsorption capacity of the odor adsorption layer material is improved, the required thickness of the adsorption layer is correspondingly reduced. Therefore, the utility model relates to the thickness design and single filling of the intermediate adsorption subsystemH produced by landfill of refuse₂Total amount of S gas and H of adsorption layer material₂S adsorption capacity. This design concept is very different from the design concept of the conventional intermediate cover layer.

Specifically, as shown in fig. 1, the odor adsorption system for a refuse landfill according to the present invention is composed of a closing adsorption subsystem 18 and a plurality of intermediate adsorption subsystems 19. The raw materials are mostly constructed by building garbage recoveries and are used for odor adsorption.

The vegetation layer 2 adopts the soil around the landfill. The loess around the selected soil is rich in nutrition, and can meet the requirements of relevant specifications on the vegetation soil in the odor adsorption system of the refuse landfill, so that no additional nutrients are needed, and the requirements beyond the relevant specifications are not required in the implementation process of the utility model. The thickness of the vegetable layer 2 is 0.5m, the degree of compaction is 80%, and the particle size curve is shown in figure 4.

The drainage layer 3 is positioned between the vegetation layer 2 and the impervious layer 4 and is built by adopting recycled coarse aggregate prepared by recycling construction waste buried in a refuse landfill site. The thickness is 0.3m, the grain diameter is 20-40mm, and the compacted relative density is 0.9.

The impermeable layer 4 is positioned on the uppermost surface of the sealing adsorption subsystem and is built by recycled fine aggregate prepared by recycling construction waste buried in a refuse landfill. The thickness is 0.4m, the maximum particle size of the recycled fine aggregate is 2mm, and the particle size grading curve is shown in figure 4. The impermeable layer is constructed by layering compaction, the compaction degree is 95%, and the permeability coefficient is between 10^-8m/s -10^-7m/s, the water absorption rate is 8 percent, and the unsaturated soil mechanical air inlet value is 5.5 kPa.

The guide and discharge layer 5 is made of recycled coarse aggregate prepared by recycling building garbage buried in a garbage burying place. The guide and drainage layer is constructed by recycled coarse aggregate, the thickness is 0.2m, the particle size is 20-40mm, the compaction relative density is 0.9, and the unsaturated soil mechanical air inlet value is 1.2 kPa.

The odor adsorption layer I6 adopts recycled fine aggregate prepared by recycling construction waste andthe regenerated powder is prepared into regenerated fine material with the thickness of 0.8m, the compactness of 95 percent, the maximum grain diameter of 2mm and the effective grain diameter d₁₀=0.02mm, and the air permeability coefficient of the compacted recycled aggregate of the odor adsorption layer I under the maximum dry density is 10^-7m/s—10^-8m/s, an air inlet value of 5kPa, water absorption of 12 percent and pore water saturation of 60 percent.

The gas collecting layer I7 is constructed by recycled coarse aggregate, the thickness is 0.3m, the particle size is 20-40mm, and the compacted relative density is not lower than 0.9.

The middle adsorption subsystem 19 comprises three functional layers, namely an upper gas collecting layer of the middle adsorption subsystem, an odor adsorption layer II of the middle adsorption subsystem and a lower gas collecting layer from top to bottom in sequence.

Wherein, the gas collecting layer 10 on the middle adsorption subsystem is constructed by recycled coarse aggregate, the thickness is 0.2m, the grain diameter is 20-40mm, and the compaction relative density is 0.9.

The odor adsorption layer II 11 of the middle adsorption subsystem is made of regenerated fine materials formed by blending regenerated fine aggregates prepared by recycling construction wastes and regenerated powder, the thickness of the odor adsorption layer II is 0.4m, and the performance parameters of the rest materials are the same as the parameter requirements of the odor adsorption layer I of the closed-field adsorption subsystem.

Wherein, the lower gas collecting layer 12 of the middle adsorption subsystem is constructed by regenerated coarse aggregate, the thickness is 0.2m, the grain diameter is 20-40mm, and the compaction relative density is 0.9.

The particle size curves of the above layers are shown in FIG. 4.

The recycled aggregate in the functional layer material is preferably recycled aggregate prepared by waste high-strength concrete, and the strength of the original concrete is required to be not lower than C20; and before the recycled aggregate is prepared from the construction wastes, impurities (including muck, steel bars, wood, glass, plastics, bricks, paper, fabrics and the like) are removed, only concrete and mortar blocks are reserved, and the weight ratio of the concrete to the mortar is not less than 95%.

And a water-permeable and air-permeable isolating material layer 9 is arranged between the functional layers, and preferably, geotextile is selected as the isolating material layer, and the geotextile meets the requirements of relevant specifications. Set up the aim at of geotechnological cloth: because the particle size difference between the functional layers of the sealing adsorption subsystem and the middle adsorption subsystem is large, the geotextile is laid in advance to prevent the mutual mixing condition from being generated in order to prevent the material with small particles from falling into the material with large particles. In addition, geotextile is laid between the gas collection layer I and the garbage body to prevent mutual mixing.

It should be noted that, in order to solve the problem that the strength of the conventional soil sealing field covering layer is too low, and the large and medium-sized construction machinery cannot normally pass through the soil sealing field covering layer in the next-stage landfill process, so that further construction difficulty is caused, the drainage layer, the guide layer, the odor adsorption layer and the air collection layer of the embodiment require a minimum bearing ratio (CBR) > 3% in the construction process so as to ensure that sufficient strength is provided, and the large and medium-sized machinery can conveniently pass through the soil sealing field covering layer in the subsequent landfill process.

It should be noted that: the particle grading shown by the particle grading curve is not unique, and can be adjusted according to the characteristics and requirements of different landfill sites in specific application scenarios.

The technical solutions provided by the embodiments of the present invention are described in detail above, and the principles and embodiments of the present invention are explained herein by using specific examples, and the descriptions of the embodiments are only used to help understanding the principles of the embodiments of the present invention; meanwhile, for a person skilled in the art, according to the embodiments of the present invention, there may be variations in the specific implementation manners and application ranges, and in summary, the content of the present description should not be construed as a limitation to the present invention.

Claims (5)

1. A landfill odor adsorption system is characterized in that: the system comprises at least one middle adsorption subsystem and a topmost field-closing adsorption subsystem; the upper part and the lower part of the middle adsorption subsystem are respectively a garbage body after the garbage landfill operation is finished, and a garbage body-middle adsorption subsystem … … -a garbage body-closing adsorption subsystem which is a composite structure formed by staggered overlapping of the garbage body-middle adsorption subsystem is finally formed; the middle adsorption subsystem comprises three functional layersThe three functional layers of an upper gas collecting layer, an odor adsorption layer II and a lower gas collecting layer are sequentially arranged from top to bottom; the sealing adsorption subsystem comprises six functional layers which are sequentially from top to bottom: the device comprises a vegetable layer, a drainage layer, an impermeable layer, a guide and exhaust layer, an odor adsorption layer I and a gas collection layer I; the odor adsorption layer I and the odor adsorption layer II are made of odor adsorption materials, and the odor adsorption materials are regeneration fine materials; the particle size distribution curve of the odor adsorption material presents a saddle shape, and specifically, according to the soil mechanics standard, the particle size grading curve characteristics of the regenerated fine materials need to meet the following conditions: (a) the maximum grain size is not more than 2 mm; (b) effective particle diameter d₁₀Not more than 0.005 mm; (c) d is not less than 1.2mm₉₀Less than or equal to 1.8 mm; (d) the non-uniformity coefficient CU is more than or equal to 5; (e) coefficient of curvature C_CBetween 1 and 3, i.e. 3. gtoreq.C_CNot less than 1; the compactness of the odor adsorption layer I and the odor adsorption layer II is respectively more than or equal to 95 percent, and the air permeability coefficients of the odor adsorption layer I, the odor adsorption layer I and the odor adsorption layer II are respectively 10 under the maximum dry density^-6m/s—10^-8m/s, air inlet values of 1 kPa-10 kPa respectively, water absorption rates of more than or equal to 10% respectively, and pore water saturation of 60% -90% respectively.

2. The landfill odor adsorption system of claim 1, wherein: the raw materials of the upper air collecting layer and the lower air collecting layer are respectively recycled and prepared recycled coarse aggregates of construction wastes, the thickness is 0.2-0.4m, the particle size is 20-40mm, and the compacted relative density is more than or equal to 0.9; the thickness of the odor adsorption layer II is 0.3-0.6 m.

3. The landfill odor adsorption system of claim 2, wherein: the vegetable layer comprises natural soil at the lower layer and surface layer nutrient soil at the upper layer of the natural soil, the thickness of the vegetable layer is more than or equal to 0.5m, and the compactness of the vegetable layer soil is more than or equal to 80 percent;

the raw material of the drainage layer is recycled and prepared recycled coarse aggregate of construction waste, the thickness is 0.2-0.4m, the particle size is 20-40mm, and the compacted relative density is more than or equal to 0.9;

the raw material of the impermeable layer is recycled fine aggregate prepared by recycling construction waste, and the recycled fine aggregate isThe maximum particle size of the aggregate is 2mm, and the effective particle size d of the particle size grading curve₁₀Not more than 0.01mm, coefficient of non-uniformity C_UNot less than 5, coefficient of curvature C_CBetween 1 and 3, i.e. 3. gtoreq.C_CNot less than 1, compactness not less than 95%, and permeability coefficient between 10^-9m/s -10^-6m/s, the water absorption is more than or equal to 8 percent, and the unsaturated soil mechanical air inlet value is more than or equal to 5 kPa;

the raw material of the guide and discharge layer is recycled and prepared recycled coarse aggregate of construction waste; the thickness of the guide and drainage layer is 0.2-0.4m, the grain diameter is 10-40mm, the compacted relative density is more than or equal to 0.9, the mechanical air intake value of unsaturated soil is not more than 1kPa, and the permeability coefficient is more than or equal to 10^-2m/s; the difference value of the air inlet values between the recycled fine aggregate of the impermeable layer and the recycled coarse aggregate of the guide and discharge layer is more than or equal to 4 kPa;

the thickness of the odor adsorption layer I is 0.4-1.0 m; the air collecting layer I is positioned between the odor adsorption layer I of the sealing adsorption subsystem and the garbage body and is constructed by regenerated coarse aggregate, the thickness is 0.3-0.5m, the particle size is 20-40mm, and the compacted relative density is not lower than 0.9.

4. The landfill odor adsorption system according to any one of claims 1 to 3, wherein: and water-permeable and air-permeable isolating material layers for preventing the raw materials of all layers from being mixed are arranged among all the functional layers for spacing.

5. The landfill odor adsorption system of claim 3, wherein: the strength of the original concrete for preparing the recycled fine aggregate and the recycled coarse aggregate of the construction waste is not lower than C10.

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