CN113277690A - Method and product for comprehensive treatment of sludge and recovery of phosphorus resources - Google Patents
Method and product for comprehensive treatment of sludge and recovery of phosphorus resources Download PDFInfo
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Abstract
The invention provides a method and a product for sludge comprehensive treatment and phosphorus resource recovery, belonging to the field of sludge treatment. The method comprises the following steps: adding a phosphorus accelerator into the sludge to be treated, and carrying out thermal hydrolysis to convert organic phosphorus into inorganic phosphorus so as to obtain a thermal hydrolysis product, wherein the phosphorus accelerator is hemicellulose and/or organic matter powder containing hemicellulose; carrying out solid-liquid separation on the thermal hydrolysis product to obtain a liquid phase product, an organic solid phase product and an inorganic solid phase product; and extracting and recovering phosphorus in the inorganic solid phase product, thereby completing the comprehensive treatment of sludge and the recovery of phosphorus resources. The invention can promote the conversion of total phosphorus to metal complex orthophosphate with higher thermal stability by coupling the phosphorus accelerator with thermal hydrolysis conditioning, so that the complex phosphorus form in the sludge is unified into the inorganic orthophosphate in a metal binding state, and further, the dispersed phosphorus-containing compound such as organic phosphorus is unified into an inorganic solid phase product, thereby realizing the high-efficiency recovery of phosphorus resources.
Description
Technical Field
The invention belongs to the field of sludge treatment, and particularly relates to a method and a product for sludge comprehensive treatment and phosphorus resource recovery.
Background
Phosphorus is an indispensable nutrient element for all living bodies, and is involved in cell construction and bioenergy reaction. However, natural phosphorus cycle is open-loop and natural phosphorus ore reserves are limited, so the problem of phosphorus resource shortage is faced. In order to realize the closed-loop phosphorus cycle, it is necessary to artificially recycle phosphorus from sludge in the phosphorus cycle. The part which flows into the ground along with the loss of the agricultural fertilizer is removed, and more than nine times of phosphorus in the natural phosphorus circulation is gathered in animal manure and sewage sludge. Wherein, the sewage sludge is a byproduct of sewage treatment, has huge yield, has an average dry basis phosphorus mass fraction as high as 2.2 percent, and is a solid waste with the first total phosphorus content. Therefore, the sewage sludge is a potential recyclable phosphorus resource.
The utilization modes of phosphorus resources in the sludge are divided into direct agricultural returning and leaching, purifying and recycling. The direct agricultural returning is to increase the bioavailability of the sludge phosphorus and obtain concentration by a simple treatment technology, and then directly return the product which is rich in phosphorus and has complex components as a phosphate fertilizer. For example, CN2018214303592 discloses a treatment apparatus for phosphorus-containing sludge, which adjusts the pH of the sludge by using phosphoric acid, and then performs filter pressing to obtain a solid phase, i.e., a semi-finished phosphate product. The technological process of leaching, purifying and recovering generally comprises three steps of phosphorus concentration, phosphorus leaching and phosphorus purification, and finally the phosphorus-rich compound with higher purity is obtained for further industrial production. E.g. CN2019108007497 discloses a resource utilization method and system for phosphorus in sludge, the method comprises the steps of adding dilute acid into wet sludge to adjust the pH value to be 0-1, reacting for 0.5-4 h, dewatering, adding NaOH into the dewatered water to obtain precipitate, adding acid into the precipitate to adjust and dissolve the precipitate, and finally adding CaCl into supernate2Obtaining the hydroxyapatite. However, since the sludge contains a large amount of harmful substances such as parasitic ova, antibiotics, heavy metals and the like, and the risk of direct returning to the field for agriculture is high, the leaching and purification process of phosphorus in the sludge is the mainstream of research of scholars.
In the field of concentration and leaching of phosphorus, researchers at home and abroad have studied and discussed methods such as acid/alkali addition, acid heat, alkali heat and the like. CN2020104937517 discloses a phosphorus recovery and utilization device and method, and the method adopts 98% sulfuric acid solution to mix and concentrate sewage sludge for hydrolysis acidification reaction to leach phosphorus. CN2020107472969 discloses a method for recovering vivianite from sludge incineration ash, which comprises mixing sludge and concentrated acid according to solid-to-liquid ratio of 0.01-0.02L/g at 25-55 deg.C for 0.5-2h, adjusting leachate with alkali liquor, and adding adsorbent for phosphorus adsorption. CN2019108902586 discloses a sludge recycling treatment method, which comprises the steps of mixing sludge with an alkaline agent and biomass powder, carrying out 16-28 h reaction on the mixed sludge at the temperature of 160-200 ℃ and under the pressure of 0.5-5 MPa, and centrifuging to obtain a phosphorus-rich liquid. CN2019101870207 discloses a method for recovering phosphorus and metal from sludge-based hydrothermal carbon, and the method comprises the step of carrying out hydrothermal carbonization reaction on mixed sludge for 1-4 hours at the temperature of 220-260 ℃ to release phosphorus. However, the above leaching and purifying technology of sludge phosphorus faces two major bottlenecks and one defect. The first bottleneck is that the water content of the sludge is high and the water is difficult to dehydrate, so that the dry-basis total phosphorus content is high but the phosphorus concentration of the wet material is low, and the economic benefit of phosphorus recovery is poor; and the bottleneck II is that the components of the sludge are complicated, variable and inhomogeneous, so that the efficiency of extracting and recovering the phosphorus greatly fluctuates. The defects are that the prior research or patent introduces excessive acid, alkali and oxidation agents in the concentration stage before the extraction of phosphorus, but most of the agents are consumed by organic components in the sludge, and the energy consumption and the cost are high.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a method and a product for sludge comprehensive treatment and phosphorus resource recovery, and aims to solve the problems of low phosphorus extraction efficiency and high energy consumption of the existing sludge.
In order to achieve the above objects, according to an aspect of the present invention, there is provided a method for sludge comprehensive disposal and phosphorus resource recovery, the method comprising the steps of:
s1, adding a phosphorus accelerator into the sludge to be treated, and carrying out thermal hydrolysis to convert organic phosphorus in the sludge to be treated into inorganic phosphorus so as to obtain a thermal hydrolysis product, wherein the phosphorus accelerator is hemicellulose and/or organic matter powder containing hemicellulose;
s2, carrying out solid-liquid separation on the thermal hydrolysis product to obtain a liquid phase product, an organic solid phase product and an inorganic solid phase product;
s3, extracting and recovering the phosphorus in the inorganic solid phase product, thereby completing the comprehensive treatment of sludge and the recovery of phosphorus resources.
More preferably, the phosphorus promoter further comprises cellulose and/or organic matter powder containing cellulose, wherein the mass fraction of hemicellulose in the phosphorus promoter is 10-100%, and the mass fraction of cellulose is 0-70%.
More preferably, the adding amount of the phosphorus promoter is 0.2-30% of the dry weight of the sludge to be treated, and the particle size of the phosphorus promoter is 20-250 meshes.
More preferably, in step S1, the temperature of the thermal hydrolysis is 60 to 200 ℃, and the time of the thermal hydrolysis is 10 to 60 min; preferably, the temperature of the thermal hydrolysis treatment is 60-160 ℃, and the time of the thermal hydrolysis treatment is 10-20 min.
More preferably, in step S2, the solid-liquid separation is performed on the thermal hydrolysis product by using a cyclone separation method, specifically including one or more of single-stage cyclone separation, two-stage cyclone separation, multi-stage cyclone separation and rotary cyclone separation.
More preferably, in step S2, the rotational speed of the cyclone is 200r/min to 1000r/min, and the time of the cyclone is 10min to 55 min.
As a further preference, the step S3 specifically includes the following sub-steps:
s31, carrying out acid heat treatment on the inorganic solid phase product to obtain a phosphorus-rich supernatant;
s32, crystallizing and precipitating the phosphorus-rich supernatant to obtain struvite or hydroxyapatite.
More preferably, in step S31, the pH of the acid heat treatment is 1.5 to 3.5, the temperature is 30 to 75 ℃, and the treatment time is 0.3 to 4 hours.
More preferably, in step S32, when the struvite crystallization method is used for crystal precipitation, the pH is 8.8 to 9.5, the molar ratio of magnesium to phosphorus is 1 to 1.8: 1, the retention time is 15 min-1 d; when the hydroxyapatite crystallization method is adopted for crystallization and precipitation, the pH value is 9.3-10.0, the molar ratio of calcium to phosphorus is 2.0-2.5: 1, the retention time is 15 min-1 d.
According to another aspect of the present invention, there is provided a phosphorus-rich compound prepared by the above method.
Generally, compared with the prior art, the above technical solution conceived by the present invention has the following beneficial effects:
1. the invention provides a method for comprehensive sludge treatment and phosphorus resource recovery, which can separate a liquid phase product, a high-calorific-value organic solid phase product and a phosphorus-rich inorganic solid phase product by coupling a phosphorus accelerator with pyrohydrolysis conditioning and solid-liquid separation, thereby realizing the comprehensive sludge treatment; meanwhile, unstable chain polysaccharide macromolecules such as hemicellulose generate a cross-linking reaction with organic macromolecules in sludge in a low-temperature thermal hydrolysis process, release and dissociation of phosphorus precipitation metal (calcium, magnesium, iron and aluminum) ions in the thermal hydrolysis reaction are accelerated, so that conversion of total phosphorus into metal complex orthophosphate with higher thermal stability is promoted, complex phosphorus forms in the sludge are unified into inorganic orthophosphate in a metal combination state, and dispersed phosphorus-containing compounds such as organic phosphorus are unified into inorganic solid-phase products, so that the obstruction of rich organic matters in the sludge on phosphorus leaching is avoided, the addition of a medicament is reduced, the resource density is greatly improved, the production period is shortened, synchronous concentration and directional shunting of organic matters and phosphorus resources in the sludge are realized within a reasonable energy consumption range, and the win-win of efficient phosphorus recovery and cost reduction is realized;
2. particularly, the composition and the adding proportion of the phosphorus promoter are optimized, so that the phosphorus promoter effect of the phosphorus promoter can be prevented from being covered by the hydrolysis reaction of sludge organic macromolecules in the thermal hydrolysis process, and the loss caused by the dissolution of cellulose and hemicellulose to cause the dissolution of sludge phosphorus from a solid phase to a liquid phase can be avoided;
3. in addition, the invention optimizes the temperature of the thermal hydrolysis treatment and the reaction condition of phosphorus extraction, utilizes the phosphorus accelerator to assist the low-temperature thermal hydrolysis, effectively reduces the thermal hydrolysis reaction condition, and further reduces the requirements on thermal hydrolysis reaction equipment.
Drawings
FIG. 1 is a schematic flow chart of sludge comprehensive treatment and phosphorus resource recovery constructed by the embodiment of the invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
According to one aspect of the invention, a method for comprehensive sludge disposal and phosphorus resource recovery is provided, which comprises the following steps:
s1, adding a phosphorus accelerator into the sludge to be treated, uniformly mixing, and performing thermal hydrolysis to convert organic phosphorus in the sludge to be treated into inorganic phosphorus so as to obtain a thermal hydrolysis product, wherein the phosphorus accelerator is hemicellulose and/or organic matter powder containing hemicellulose; further preferably, the phosphorus promoter also comprises cellulose and/or organic matter powder containing cellulose;
s2, carrying out solid-liquid separation on the thermal hydrolysis product to obtain a liquid phase product, a light organic solid phase product and a heavy inorganic solid phase product, and then collecting the liquid phase product and the organic solid phase product;
s3, extracting and recovering the phosphorus in the inorganic solid phase product, thereby completing the comprehensive treatment of sludge and the recovery of phosphorus resources.
Further, in step S1, the mass fraction of hemicellulose in the phosphorus promoter is 10% to 100%, and the mass fraction of cellulose is 0% to 90%. Hemicellulose is a heteromultimer composed of several different types of monosaccharides, contains a large number of unstable carboxyl groups and branched chains, is easily soluble in water and acidic, is bound to the surface of cellulose microfibril in biomass, and coexists with cellulose. Cellulose is composed of non-reducing end groups, anhydroglucose units and reducing end groups. Besides the synergistic effect of the cellulose in the phosphorus promoter and the hemicellulose, the phosphorus promoter participates in the sludge pyrohydrolysis reaction and promotes the sludge phosphorus form conversion, and can provide an attachment space for the hemicellulose and prevent the independent hemicellulose from absorbing water and being bonded so as to be hydrolyzed and denatured. Therefore, the mass fraction of hemicellulose in the phosphorus promoter is preferably 10-80%, and the mass fraction of cellulose is preferably 20-70%.
The sludge to be treated is municipal sludge and/or oily sludge and/or printing and dyeing sludge, the water content is 85.0-99.9%, and the addition amount of the phosphorus accelerator is 0.2-30% of the dry basis weight of the sludge to be treated. By optimizing the components and the adding proportion of the phosphorus promoter, the phosphorus promoter effect of the phosphorus promoter caused by too low proportion of hemicellulose and cellulose can be prevented from being covered by the hydrolysis reaction of sludge organic macromolecules in the thermal hydrolysis process. Meanwhile, because the cellulose and the hemicellulose are dissolved in an acidic state in the thermal hydrolysis process, the problem that the pH is too low due to too high proportion of the hemicellulose and the cellulose can be avoided through optimization, and the sludge phosphorus is dissolved out from a solid phase to a liquid phase to cause loss. In addition, the particle size of the phosphorus promoter is 20-250 meshes, so that the uniform mixing of the phosphorus promoter and the sludge is ensured, and the gelatinization reaction is not easy to occur.
Further, in step S1, the phosphorous accelerator assists low-temperature thermal hydrolysis, and can accelerate the effect of inorganic solid phone total phosphorous at a lower temperature, thereby reducing sludge treatment energy consumption through coupled gain effect. Specifically, the pyrohydrolysis treatment technology can effectively break away sludge extracellular polymeric substances, release intracellular biological organic macromolecules and further promote sludge stabilization and homogenization, and meanwhile, the closed high-pressure environment in the pyrohydrolysis process can degrade the organic macromolecules in the sludge into small molecules and further convert the small molecules into inorganic substances with high thermal stability. In order to achieve the effect of converting organic phosphorus in the sludge into inorganic phosphorus, the independent thermal hydrolysis temperature of the sludge is at least 200-260 ℃, even higher; after the addition of the phosphorus accelerator, the effect of the phosphorus accelerator for accelerating the release and decomposition of the intracellular organic phosphorus is coupled and enhanced with the effect of the thermal hydrolysis technology, and through scientific research and practical implementation, the temperature of the auxiliary thermal hydrolysis treatment of the phosphorus accelerator can be as low as 60-200 ℃, the optimal temperature condition is 60-160 ℃, and the time of the thermal hydrolysis treatment is 10-20 min.
Further, in step S2, solid-liquid separation is performed on the thermal hydrolysis product by using a cyclone separation method, specifically including one or more of single-stage cyclone separation, two-stage cyclone separation, multi-stage cyclone separation, and rotary cyclone separation. The rotational speed of the cyclone separation is 200 r/min-1000 r/min, and the time of the cyclone separation is 10 min-55 min. The cyclone separation process does not have the effect of screening phosphorus-rich compounds from complex substances such as sludge, and the working principle of the cyclone separation process is to efficiently mix or separate particles with different densities by using the inertia of the particles under high centrifugal force. The combination of the phosphorus accelerator assisted thermal hydrolysis technology and the multistage cyclone separation technology is adopted, organic phosphorus in wet materials is solidified, and then organic and inorganic separation is utilized, so that high concentration of phosphorus is realized, and enrichment and purification are facilitated. Meanwhile, phosphorus resources and organic matters in the phosphorus-rich solid waste are separated, the wrapping effect of sludge organic components on phosphorus and the additional consumption of the sludge organic components on phosphorus leaching agents are eliminated, the agent adding amount and cost of a subsequent phosphorus recovery process are greatly reduced, and the benefit maximization of phosphorus resource recovery in the phosphorus-rich sludge is ingeniously realized.
Further, step S3 specifically includes the following sub-steps:
s31, carrying out acid heat treatment on the inorganic solid phase product, and adjusting the pH to 1.5-3.5 by adding sulfuric acid, hydrochloric acid or nitric acid with the concentration of 0.1-1M, wherein the acid heat treatment temperature is 30-75 ℃, and the treatment time is 0.3-4 h, so as to obtain a phosphorus-rich supernatant, and the phosphorus leaching rate is 62-97%;
s32 crystallizing and precipitating the phosphorus-rich supernatant to obtain struvite or hydroxyapatite.
Wherein, when the struvite crystallization method is adopted for crystallization and precipitation, the pH is adjusted to be 8.8-9.5 by adding 0.1-1M sodium hydroxide, sodium carbonate or calcium hydroxide, and the magnesium-phosphorus molar ratio is adjusted to be 1-1.8 by adding magnesium oxide or magnesium carbonate: 1, the retention time is 15 min-1 d. More preferably, the treatment conditions of the struvite crystallization method are preferably that the pH is 9.0-9.3, the magnesium-phosphorus molar ratio is 1.6-1.8: 1, the retention time is 15 min-4 h.
When the hydroxyapatite crystallization method is adopted for crystallization and precipitation, the pH is adjusted to 9.3-10.0 by adding 0.1-1M sodium hydroxide, sodium carbonate or calcium hydroxide, and the molar ratio of calcium to phosphorus is adjusted to 2.0-2.5 by adding calcium oxide or calcium carbonate: 1, the retention time is 15 min-1 d. More preferably, the treatment conditions of the hydroxyapatite crystallization method are preferably that the pH is 9.5-10.0, the molar ratio of calcium to phosphorus is 2.2-2.5: 1, the retention time is 15 min-6 h.
The efficiency of phosphorus leaching purification depends on the morphological distribution of phosphorus in the phosphorus-rich solid waste. The phosphorus in the sludge can be divided into organic phosphorus mainly comprising inositol phosphatide, phosphotriester, pyrophosphate and polyphosphate and inorganic phosphorus mainly comprising hydroxide and metal oxide complex phosphate and metal ion combined orthophosphate. On one hand, cellulose and hemicellulose in the phosphorus promoter mainly contain unstable chain polysaccharide macromolecule components, and can generate a crosslinking reaction with organic macromolecules in sludge in a thermal hydrolysis process, so that the release and dissociation of phosphorus precipitation metal (calcium, magnesium, iron and aluminum) ions are accelerated, the conversion of total phosphorus into metal complex orthophosphate with higher thermal stability is promoted, the process of converting organic phosphorus into inorganic phosphorus in the thermal hydrolysis reaction is accelerated, and the subsequent uniform leaching and purification of phosphorus are facilitated; on the other hand, the phosphorus accelerator produces acid through hydrolysis, promotes different forms of phosphorus in the sludge to be converted into metal binding state orthophosphate, increases the tendency of phosphorus to migrate to a product solid phase, unifies dispersed phosphorus-rich compounds into inorganic components of the solid phase product, and further improves the leaching benefit of phosphorus-rich solid waste phosphorus. The invention does not directly carry out phosphorus leaching and recovery on sludge rich in organic matters, but realizes directional separation and concentration of phosphorus resources and organic matters in the sludge through coupling of the phosphorus accelerator and thermal hydrolysis, and avoids the problems of high consumption of chemicals and long period in phosphorus leaching caused by difficult leaching of intracellular organic macromolecule combined phosphorus and high activity of reductive organic matters.
According to another aspect of the present invention, there is provided a phosphorus-rich compound prepared by the above method.
The technical solution provided by the present invention is further explained below according to specific embodiments.
Example 1
Preparing a phosphorus promoter: agricultural and forestry solid waste straw, bagasse, wood chips, bamboo materials and industrial cellulose are selected and crushed into powder with the characteristic particle size of below 150 meshes by a crusher. Respectively preparing a phosphorus accelerator A: straw powder, hemicellulose content 42%, cellulose content 44%; and (3) a phosphorus promoter B: the mass ratio of the straw powder to the sawdust powder is 1: 3, 20% of hemicellulose content and 48% of cellulose content; and (3) a phosphorus promoter C: the mass ratio of straw powder, bagasse powder and wood dust powder is 1: 2: 2, hemicellulose content of 26%, cellulose content of 20%; and (3) a phosphorus promoter D: the mass ratio of cellulose powder, wood dust powder and bamboo powder is 3: 1: 3, hemicellulose content of 37% and cellulose content of 70%.
The phosphorus promoter assists the thermal hydrolysis treatment: municipal sludge with the water content of 99% is respectively mixed with the phosphorus accelerator A, B, C, D, the total adding amount is 10% of the dry basis weight of the sludge, and the mixture is uniformly stirred. Performing thermal hydrolysis treatment at 160 deg.C for 10min by adopting electric heating coupled with solar heating to obtain thermal hydrolysis product.
And (3) cyclone separation: two-stage cyclone separation is adopted for 10min, the rotating speed is 800r/min, and an upper layer, a middle layer and a lower layer which are respectively a sludge liquid phase, an organic solid phase and an inorganic solid phase are obtained.
Dehydrating and heat drying the organic solid phase to obtain low-phosphorus high-organic-matter products I, II, III and IV.
Leaching and purifying inorganic solid phase phosphorus: adjusting the pH value of the inorganic solid phase to 3.0 by using 0.2M sulfuric acid, indirectly heating the inorganic solid phase for 0.5h at 75 ℃ by using flue gas generated by waste heat of a power plant, and centrifuging to obtain supernatant liquid to obtain phosphorus leachate; magnesium chloride is used as a magnesium source, and the molar ratio of magnesium to phosphorus in the phosphorus leaching solution is adjusted to be 1.6: 1, adjusting the pH value of the phosphorus leaching solution to 9.0 by adopting 0.1M sodium hydroxide solution, uniformly stirring, standing for 4 hours, and filtering to obtain the crystalline struvite I, II, III and IV.
The low phosphorus product and the phosphorus-rich compound prepared in example 1:
the total phosphorus content of the low-phosphorus product I is 0.18mg/g DS; the purity of the struvite I is 88.2 percent, and the recovery rate is 88.5 percent;
the total phosphorus content of the low-phosphorus product II is 0.16mg/g DS; the purity of the struvite II is 87.1 percent, and the recovery rate is 89.6 percent;
the total phosphorus content of the low-phosphorus product III is 0.16mg/g DS; the purity of struvite III is 87.6 percent, and the recovery rate is 88.7 percent;
the total phosphorus content of the low-phosphorus product IV is 0.12mg/g DS; the purity of struvite IV is 88.1 percent, and the recovery rate is 89.1 percent.
Example 2
Preparing a phosphorus promoter: selecting bark, sawdust and xylan, and crushing the bark, the sawdust and the xylan into powder with the characteristic particle size of below 250 meshes by a crusher. According to the mass ratio of bark, sawdust and xylan of 4: 1: 3, uniformly mixing to obtain the phosphorus promoter with the hemicellulose content of 80 percent and the cellulose content of 23 percent.
The phosphorus promoter assists the thermal hydrolysis treatment: mixing the oil-containing sludge with the water content of 95% with a phosphorus promoter, wherein the total adding amount is 30% of the dry basis weight of the sludge, and uniformly stirring. Heating at 60 deg.C, 80 deg.C, and 100 deg.C for 20min to obtain thermal hydrolysis sludge A, B, C.
And (3) cyclone separation: a solid-liquid cyclone separator with the rotation speed of 200r/min and a solid-solid cyclone separator with the rotation speed of 900r/min are sequentially adopted for composite separation for 55min to obtain a sludge liquid phase, an organic solid phase and an inorganic solid phase.
Dehydrating and heat drying the organic solid phase to obtain low-phosphorus high-organic matter products I, II and III.
Leaching and purifying inorganic solid phase phosphorus: adjusting the pH value of the inorganic solid phase to 1.5 by using 0.1M nitric acid, heating for 0.3h at 60 ℃ by using a sewage source heat pump, and centrifuging to obtain a supernatant to obtain a phosphorus leaching solution; magnesium carbonate and magnesium oxide are adopted as magnesium sources, and the molar ratio of magnesium to phosphorus in the phosphorus leaching solution is adjusted to be 1.8: 1, adjusting the pH value of the phosphorus leaching solution to 9.5 by adopting 0.5M sodium hydroxide solution, uniformly stirring, standing for 1d, and filtering to obtain the crystalline struvite I, II and III.
The low phosphorus product and the phosphorus-rich compound prepared in this example 2:
the total phosphorus content of the low-phosphorus product I is 0.18mg/g DS; the purity of the struvite I is 86.3 percent, and the recovery rate is 88.9 percent;
the total phosphorus content of the low-phosphorus product II is 0.09mg/g DS; the purity of struvite II is 86.8 percent, and the recovery rate is 93.6 percent;
the total phosphorus content of the low-phosphorus product III is 0.24mg/g DS; the purity of struvite III is 86.4 percent, and the recovery rate is 93.0 percent.
Example 3
Preparing a phosphorus promoter: selecting industrial cellulose and wheat bran with the particle size of 250 meshes, and mixing the raw materials in a mass ratio of 6: 1, uniformly mixing to obtain the phosphorus promoter with the hemicellulose content of 10 percent and the cellulose content of 90 percent.
Thermal hydrolysis treatment: and (3) performing thermal hydrolysis treatment on the municipal sludge with the water content of 95% for 25min at 120 ℃, 160 ℃ and 200 ℃ respectively by adopting electric heating to obtain thermal hydrolysis sludge A, B, C.
And (3) cyclone separation: and (3) separating for 30min at the rotating speed of 1000r/min by adopting a solid-liquid-gas three-phase cyclone separator to obtain a sludge liquid phase, an organic solid phase and an inorganic solid phase.
Dehydrating and heat drying the organic solid phase to obtain low-phosphorus high-organic matter products I, II and III.
Leaching and purifying inorganic solid phase phosphorus: adjusting the pH value of the inorganic solid phase to 3.5 by using 0.5M nitric acid, heating for 2 hours at 60 ℃ by using a sewage source heat pump, centrifuging and taking supernate to obtain phosphorus leachate; calcium oxide and calcium chloride are used as calcium sources, and the molar ratio of calcium to phosphorus in the phosphorus leaching solution is adjusted to be 2.2: 1, regulating the pH value of the phosphorus leaching solution to 10.0 by adopting a 1M sodium hydroxide solution, uniformly stirring, standing for 6 hours, and filtering to obtain crystalline hydroxyapatite I, II and III.
The low phosphorus product and the phosphorus-rich compound prepared in example 3:
the total phosphorus content of the low-phosphorus product I is 0.04mg/g DS; the purity of the hydroxyapatite I is 83.1 percent, and the recovery rate is 83.6 percent;
the total phosphorus content of the low-phosphorus product II is 0.07mg/g DS; the purity of the hydroxyapatite II is 85.7 percent, and the recovery rate is 87.9 percent;
the total phosphorus content of the low-phosphorus product III is 0.06mg/g DS; the purity of the hydroxyapatite III is 85.6 percent, and the recovery rate is 87.8 percent.
Example 4
Preparing a phosphorus promoter: industrial grade xylan is selected and crushed into powder with the characteristic particle size of 150-250 meshes by a crusher, and the phosphorus promoter with the hemicellulose content of 100% and the cellulose content of 0% is obtained.
The phosphorus promoter assists the thermal hydrolysis treatment: mixing the printing and dyeing sludge with the water content of 93% with a phosphorus accelerator, wherein the total adding amount is 0.2% of the dry basis weight of the sludge, and uniformly stirring. Carrying out thermal hydrolysis treatment at 150 ℃ for 60min by adopting electric heating to obtain thermal hydrolysis sludge.
And (3) cyclone separation: and separating for 20min by adopting a multistage cyclone separator with the rotating speed of 600-900 r/min to obtain a sludge liquid phase, an organic solid phase and an inorganic solid phase.
Dehydrating and heat drying the organic solid phase to obtain a low-phosphorus high-organic matter product.
Leaching and purifying inorganic solid phase phosphorus: adjusting the pH value of the inorganic solid phase to 3.5 by using 1M hydrochloric acid, heating for 4 hours at 30 ℃ by using a sewage source heat pump, centrifuging and taking supernate to obtain phosphorus leachate; magnesium carbonate and magnesium oxide are adopted as magnesium sources, and the molar ratio of magnesium to phosphorus in the phosphorus leaching solution is adjusted to be 1: 1. 1.4: 1. 1.6: 1, adjusting the pH value of the phosphorus leaching solution to 8.8 by adopting a 1M sodium hydroxide solution, uniformly stirring, standing for 15min, and filtering to obtain the crystalline struvite I, II and III.
The low phosphorus product and the phosphorus-rich compound prepared in example 4:
the total phosphorus content of the low-phosphorus product is 0.19mg/g DS;
the purity of the struvite I is 83.5 percent, and the recovery rate is 88.0 percent;
the purity of the struvite II is 85.3 percent, and the recovery rate is 89.1 percent;
the purity of struvite III is 85.6 percent, and the recovery rate is 89.4 percent.
Example 5
Preparing a phosphorus promoter: selecting wood chips and cellulose, and crushing the wood chips and the cellulose into powder with the characteristic particle size of below 400 meshes by a crusher. According to the mass ratio of the wood chips to the cellulose of 4: 1, uniformly mixing to obtain the phosphorus promoter with the hemicellulose content of 18 percent and the cellulose content of 66 percent.
The phosphorus promoter assists the thermal hydrolysis treatment: municipal sludge with the water content of 97 percent is mixed with a phosphorus accelerator, the total adding amount is 15 percent of the dry basis weight of the sludge, and the mixture is stirred uniformly. Carrying out thermal hydrolysis treatment at 150 ℃ for 15min by adopting electric heating to obtain thermal hydrolysis sludge.
And (3) cyclone separation: and separating for 20min by adopting a multistage cyclone separator with the rotating speed of 300-600 r/min to obtain a sludge liquid phase, an organic solid phase and an inorganic solid phase.
Dehydrating and heat drying the organic solid phase to obtain a low-phosphorus high-organic matter product.
Leaching and purifying inorganic solid phase phosphorus: adjusting the pH value of the inorganic solid phase to 3.0 by using 0.1M nitric acid, heating for 2 hours at 60 ℃ by using a sewage source heat pump, centrifuging and taking supernate to obtain phosphorus leachate; calcium oxide and calcium chloride are used as calcium sources, the molar ratio of calcium to phosphorus of the phosphorus leaching solution is adjusted to be 2.1:1, 2.3:1 and 2.5:1 respectively, 0.1M sodium hydroxide solution is used for adjusting the pH of the phosphorus leaching solution to be 9.5, the solution is stirred uniformly and then stands for 1d, and crystalline hydroxyapatite I, crystalline hydroxyapatite II and crystalline hydroxyapatite III are obtained through filtration.
The low phosphorus product and the phosphorus-rich compound prepared in example 5:
the total phosphorus content of the low-phosphorus product is 0.07mg/g DS;
the purity of the hydroxyapatite I is 83.1 percent, and the recovery rate is 94.8 percent;
the purity of the hydroxyapatite II is 85.3 percent, and the recovery rate is 97.0 percent;
the purity of the hydroxyapatite III is 88.2 percent, and the recovery rate is 96.4 percent.
Example 6
Preparing a phosphorus promoter: the method comprises the steps of selecting tree roots, bamboo materials and wood chips, and crushing the tree roots, the bamboo materials and the wood chips into powder with the characteristic particle size of 200-250 meshes by a crusher. Uniformly mixing the tree roots, the bamboo materials and the wood chips in a mass ratio of 2:1:1 to obtain the phosphorus accelerator with the hemicellulose content of 31% and the cellulose content of 42%.
The phosphorus promoter assists the thermal hydrolysis treatment: mixing municipal sludge with water content of 99% with a phosphorus accelerator, wherein the total adding amount is 15% of the dry basis weight of the sludge, and uniformly stirring. Carrying out thermal hydrolysis treatment for 15min at 160 ℃ by adopting electric heating to obtain the thermal hydrolysis sludge.
And (3) cyclone separation: and separating for 20min by adopting a multistage cyclone separator with the rotating speed of 900r/min to obtain a sludge liquid phase, an organic solid phase and an inorganic solid phase.
Dehydrating and heat drying the organic solid phase to obtain a low-phosphorus high-organic matter product.
Leaching and purifying inorganic solid phase phosphorus: adjusting the pH value of the inorganic solid phase to 3.0 by using 0.1M nitric acid, heating for 4 hours at 75 ℃ by using a sewage source heat pump, centrifuging and taking supernate to obtain phosphorus leachate; calcium oxide and calcium chloride are adopted as calcium sources, and the molar ratio of calcium to phosphorus in the phosphorus leaching solution is adjusted to be 2.0: 1, regulating the pH of the phosphorus leaching solution to 9.3, 9.5 and 9.7 respectively by using 1M sodium hydroxide solution, uniformly stirring, standing for 15min, and filtering to obtain crystalline hydroxyapatite I, II and III.
The low phosphorus product and the phosphorus-rich compound prepared in example 6:
the total phosphorus content of the low-phosphorus product is 0.06mg/g DS;
the purity of the hydroxyapatite I is 83.1 percent, and the recovery rate is 85.9 percent;
the purity of the hydroxyapatite II is 89.3 percent, and the recovery rate is 85.0 percent;
the purity of the hydroxyapatite III is 88.2 percent, and the recovery rate is 88.4 percent.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (10)
1. A method for sludge comprehensive treatment and phosphorus resource recovery is characterized by comprising the following steps:
s1, adding a phosphorus accelerator into the sludge to be treated, and carrying out thermal hydrolysis to convert organic phosphorus in the sludge to be treated into inorganic phosphorus so as to obtain a thermal hydrolysis product, wherein the phosphorus accelerator is hemicellulose and/or organic matter powder containing hemicellulose;
s2, carrying out solid-liquid separation on the thermal hydrolysis product to obtain a liquid phase product, an organic solid phase product and an inorganic solid phase product;
s3, extracting and recovering the phosphorus in the inorganic solid phase product, thereby completing the comprehensive treatment of sludge and the recovery of phosphorus resources.
2. The method for sludge comprehensive disposal and phosphorus resource recovery according to claim 1, wherein the phosphorus promoter further comprises cellulose and/or organic matter powder containing cellulose, the mass fraction of hemicellulose in the phosphorus promoter is 10-100%, and the mass fraction of cellulose is 0-70%.
3. The method for sludge comprehensive disposal and phosphorus resource recovery according to claim 1, wherein the addition amount of the phosphorus promoter is 0.2 to 30% of the dry weight of the sludge to be treated, and the particle size of the phosphorus promoter is 20 to 250 meshes.
4. The method for sludge comprehensive disposal and phosphorus resource recovery as claimed in claim 1, wherein in step S1, the temperature of the thermal hydrolysis treatment is 60 ℃ to 200 ℃, and the time of the thermal hydrolysis treatment is 10min to 60 min; preferably, the temperature of the thermal hydrolysis treatment is 60-160 ℃, and the time of the thermal hydrolysis treatment is 10-20 min.
5. The method for sludge comprehensive disposal and phosphorus resource recovery as claimed in claim 1, wherein in step S2, the thermal hydrolysis product is subjected to solid-liquid separation by means of cyclone separation, specifically including one or more of single-stage cyclone separation, two-stage cyclone separation, multi-stage cyclone separation and rotary cyclone separation.
6. The method for sludge comprehensive disposal and phosphorus resource recovery as claimed in claim 5, wherein in step S2, the rotational speed of the cyclone separation is 200r/min to 1000r/min, and the time of the cyclone separation is 10min to 55 min.
7. The method for sludge comprehensive disposal and phosphorus resource recovery as claimed in claim 1, wherein step S3 comprises the following substeps:
s31, carrying out acid heat treatment on the inorganic solid phase product to obtain a phosphorus-rich supernatant;
s32, crystallizing and precipitating the phosphorus-rich supernatant to obtain struvite or hydroxyapatite.
8. The method for sludge comprehensive disposal and phosphorus resource recovery as claimed in claim 7, wherein in step S31, the pH of the acid heat treatment is 1.5-3.5, the temperature is 30-75 ℃, and the treatment time is 0.3-4 h.
9. The method for sludge comprehensive disposal and phosphorus resource recovery according to claim 7, wherein in step S32, when struvite crystallization is used for crystallization precipitation, the pH is 8.8-9.5, the molar ratio of magnesium to phosphorus is 1-1.8: 1, the retention time is 15 min-1 d; when the hydroxyapatite crystallization method is adopted for crystallization and precipitation, the pH value is 9.3-10.0, the molar ratio of calcium to phosphorus is 2.0-2.5: 1, the retention time is 15 min-1 d.
10. A phosphorus-rich compound produced by the method of any one of claims 1 to 9.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115159489A (en) * | 2022-07-15 | 2022-10-11 | 华中科技大学 | Method and system for modifying sludge to fix phosphorus and recovering phosphorus based on acid leaching of incineration ash |
| CN115815317A (en) * | 2022-12-15 | 2023-03-21 | 浙江工业大学台州研究院 | Method for recycling sludge and preparing soil conditioner |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009035441A (en) * | 2007-07-31 | 2009-02-19 | Hiroshima Univ | Method for recovering phosphate |
| CN104692837A (en) * | 2015-02-13 | 2015-06-10 | 重庆工商大学 | Method of comprehensively utilizing sludge |
| CN106830587A (en) * | 2017-01-19 | 2017-06-13 | 同济大学 | It is a kind of to strengthen the method for explaining phosphorus containing solid sludge high temperature hot water high |
| CN106995350A (en) * | 2017-03-27 | 2017-08-01 | 深圳先进技术研究院 | The preparation method and sludge base charcoal slow-release phosphate fertilizer of sludge base charcoal slow-release phosphate fertilizer |
| CN107417062A (en) * | 2017-09-08 | 2017-12-01 | 复旦大学 | A kind of method that phosphorus is reclaimed from sludge from wastewater treatment plant |
| CN109592659A (en) * | 2019-01-20 | 2019-04-09 | 重庆大学 | A kind of method of municipal sludge hydrothermal carbonization recycling phosphorus |
| CN110540479A (en) * | 2019-09-19 | 2019-12-06 | 东北农业大学 | sludge recycling treatment method |
| CN110845107A (en) * | 2019-10-25 | 2020-02-28 | 西安理工大学 | Method for improving phosphorus recovery efficiency in sludge and promoting anaerobic digestion |
| CN112174454A (en) * | 2020-09-10 | 2021-01-05 | 同济大学 | Method for recycling sludge resources in different-quality and phase-splitting gradient manner |
-
2021
- 2021-05-12 CN CN202110516641.2A patent/CN113277690B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009035441A (en) * | 2007-07-31 | 2009-02-19 | Hiroshima Univ | Method for recovering phosphate |
| CN104692837A (en) * | 2015-02-13 | 2015-06-10 | 重庆工商大学 | Method of comprehensively utilizing sludge |
| CN106830587A (en) * | 2017-01-19 | 2017-06-13 | 同济大学 | It is a kind of to strengthen the method for explaining phosphorus containing solid sludge high temperature hot water high |
| CN106995350A (en) * | 2017-03-27 | 2017-08-01 | 深圳先进技术研究院 | The preparation method and sludge base charcoal slow-release phosphate fertilizer of sludge base charcoal slow-release phosphate fertilizer |
| CN107417062A (en) * | 2017-09-08 | 2017-12-01 | 复旦大学 | A kind of method that phosphorus is reclaimed from sludge from wastewater treatment plant |
| CN109592659A (en) * | 2019-01-20 | 2019-04-09 | 重庆大学 | A kind of method of municipal sludge hydrothermal carbonization recycling phosphorus |
| CN110540479A (en) * | 2019-09-19 | 2019-12-06 | 东北农业大学 | sludge recycling treatment method |
| CN110845107A (en) * | 2019-10-25 | 2020-02-28 | 西安理工大学 | Method for improving phosphorus recovery efficiency in sludge and promoting anaerobic digestion |
| CN112174454A (en) * | 2020-09-10 | 2021-01-05 | 同济大学 | Method for recycling sludge resources in different-quality and phase-splitting gradient manner |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115159489A (en) * | 2022-07-15 | 2022-10-11 | 华中科技大学 | Method and system for modifying sludge to fix phosphorus and recovering phosphorus based on acid leaching of incineration ash |
| CN115159489B (en) * | 2022-07-15 | 2024-06-11 | 华中科技大学 | Method and system for sludge modified phosphorus fixation and phosphorus recovery based on incineration ash acid leaching |
| CN115815317A (en) * | 2022-12-15 | 2023-03-21 | 浙江工业大学台州研究院 | Method for recycling sludge and preparing soil conditioner |
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