CN114231290A - Method for hydrothermal liquid resource utilization of excess sludge - Google Patents

Method for hydrothermal liquid resource utilization of excess sludge Download PDF

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CN114231290A
CN114231290A CN202111561409.7A CN202111561409A CN114231290A CN 114231290 A CN114231290 A CN 114231290A CN 202111561409 A CN202111561409 A CN 202111561409A CN 114231290 A CN114231290 A CN 114231290A
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hydrothermal
soil
solution
excess sludge
hydrothermal solution
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陈红
王秀兰
于鑫
薛罡
于露滢
王凯
曾可佳
叶沁辉
郑凯远
钱雅洁
李响
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Donghua University
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    • C09K17/00—Soil-conditioning materials or soil-stabilising materials
    • C09K17/14—Soil-conditioning materials or soil-stabilising materials containing organic compounds only
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    • C—CHEMISTRY; METALLURGY
    • C05—FERTILISERS; MANUFACTURE THEREOF
    • C05F—ORGANIC FERTILISERS NOT COVERED BY SUBCLASSES C05B, C05C, e.g. FERTILISERS FROM WASTE OR REFUSE
    • C05F7/00—Fertilisers from waste water, sewage sludge, sea slime, ooze or similar masses
    • C—CHEMISTRY; METALLURGY
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    • C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
    • C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
    • C05G3/80—Soil conditioners
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    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
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    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
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Abstract

The invention discloses a resource utilization method of hydrothermal solution of excess sludge, which comprises the steps of inhibiting the generation of high molecular polymers in the hydrothermal process of the sludge by adding a catalyst, carrying out soil leaching treatment on the generated hydrothermal solution, removing nitrogen and phosphorus substances and a small amount of high molecular organic matters in the hydrothermal solution through soil adsorption and interception effects, using a soil filter material with saturated adsorption as a soil conditioner, and carrying out resource utilization on leachate generated after the hydrothermal solution is subjected to soil leaching as a carbon source for biological nitrogen removal of sewage. The method carries out resource utilization in different ways based on the characteristics of the components of the hydrothermal solution of the sludge, does not need to add extra medicament in the hydrothermal solution resource process, has simple operation, lower cost and easy engineering, and provides a feasible method for the hydrothermal solution resource utilization of the residual sludge.

Description

Method for hydrothermal liquid resource utilization of excess sludge
Technical Field
The invention belongs to the technical field of sludge recycling, and particularly relates to a method for recycling hydrothermal liquid of sludge.
Background
The biological sewage treatment process is accompanied by the generation of a large amount of excess sludge, and the resource utilization of the sludge becomes an important direction for the treatment and disposal of the excess sludge because the sludge contains high-content organic matters. In view of the problem that carbon source is lack and organic carbon is needed to be added in the biological sewage denitrification treatment process, organic matters in the sludge are converted to prepare the sewage denitrification carbon source, which becomes a research hotspot for recycling the sludge.
At present, methods for converting excess sludge into a sewage biological denitrification carbon source mainly comprise sludge anaerobic fermentation for producing short chain fatty acids (VFA) and a sludge pyrohydrolysis method. In the anaerobic fermentation process of the sludge, cell components such as proteins, polysaccharides and the like are gradually converted into small molecular organic acids such as acetic acid, propionic acid, butyric acid and the like by sludge microorganisms through cell dissolution, hydrolysis and acidification processes, and the small molecular organic acids can be used as a denitrification carbon source for biological nitrogen removal of sewage. In addition, the sludge hydrothermal reaction process generates cracking to generate small molecular substances, the produced hydrothermal liquid can be used as a denitrification carbon source, and the sludge hydrothermal reaction has high reaction rate and high efficiency and becomes a development trend of sludge resource in recent years, but researches find that proteins and polysaccharides which are main components in the sludge easily generate Maillard reaction under the high-temperature hydrothermal condition to generate a high polymer Maillard product which is difficult to remove in the biological treatment process and even has an inhibiting effect on microorganisms, so that the effectiveness of organic matters in the hydrothermal liquid as the denitrification carbon source is low; meanwhile, the sludge hydrothermal solution also has the problem of release of high-concentration nitrogen and phosphorus, and in order to reduce the nitrogen and phosphorus load additionally introduced when the sludge hydrothermal solution is used as a denitrification carbon source, the nitrogen and phosphorus recovery pretreatment of the feed water is also needed, while the struvite recovery method is still the most common treatment method, so that the cost is higher. Therefore, the formation of maillard reaction products and the high concentration of nitrogen and phosphorus in the hydrothermal solution become important factors for limiting the hydrothermal solution as a denitrification carbon source.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a method for recycling hydrothermal solution of excess sludge, which can inhibit the generation of difficultly biodegradable Maillard products in the hydrothermal solution and change the recycling direction of high-concentration nitrogen and phosphorus in the hydrothermal solution.
In order to achieve the aim, the invention provides a hydrothermal solution resource utilization method of excess sludge, which comprises the following steps:
step 1): adding a catalyst into a closed reactor containing sludge, and carrying out hydrothermal reaction to obtain biochar and hydrothermal liquid;
step 2): pretreating the hydrothermal solution by soil leaching, wherein nitrogen and phosphorus in the hydrothermal solution and high-molecular organic matters are trapped by soil, and leaching solution is obtained at the same time;
step 3): the leached soil is used as a soil conditioner, and the leachate is recycled to sewage treatment and used as a biological denitrification carbon source.
Preferably, the water content of the sludge in the step 1) is 85-98%, and the total organic matter concentration is 5-150 g/L.
Preferably, the catalyst in step 1) of the present invention comprises sulfuric acid, citric acid, FeCl2、FeCl3One or more of (a).
Preferably, the catalyst in step 1) of the present invention is sulfuric acid and citric acid, one or a mixture of them is selected, the addition amount of sulfuric acid is 0.001-0.01 mol/g VSS, the addition amount of citric acid is 0.001-0.15 mol/g VSS, and when the two are used in combination, the molar ratio of sulfuric acid to citric acid is 1:0.1-0.1: 10.
Preferably, the catalyst of step 1) of the present invention is a catalyst FeCl2And FeCl3One or a mixture of the two is selected, FeCl2The addition amount of FeCl is 5-100 mg of Fe/gVSS3The addition amount of (b) is 10-150 mg Fe/gVSS, and when the two are mixed for use, FeCl2With FeCl3The mass ratio of 1: 0.2-0.1: 1.
preferably, the hydrothermal reaction temperature in step 1) of the present invention is 140-0C, the hydrothermal reaction time is 0.5-8 h.
Preferably, the closed reactor in the step 1) is a temperature-resistant, pressure-resistant and corrosion-resistant closed reactor, and an anti-corrosion lining layer is arranged inside the closed reactor.
Preferably, after the hydrothermal reaction in step 1) of the present invention is finished, after the reactor is cooled to room temperature, the hydrothermal mixed solution is centrifuged to obtain a liquid hydrothermal solution and a solid biochar, respectively, wherein the hydrothermal solution has a COD of 5-200 g/L.
Preferably, the soil in the step 2) of the invention is barren soil, leaching is in a filter tank form, the soil is used as a filter material of the filter tank, hydrothermal liquid is uniformly sprayed from the surface of the filter tank, and the volume load is 1-20 m3/(m2D), the mass ratio of the hydrothermal solution to the soil is 0.3:1-2:1, and the leaching solution is the liquid leached by the soil.
Preferably, the soil conditioner in the step 3), namely the soil serving as the filter material in the step 2) is taken out from the filter after being saturated, and then is returned to the soil to be mixed with the native soil for improving the fertility of the native soil; the leaching solution is refluxed to the front end of the inlet water of a sewage treatment plant or to the biological denitrification and denitrification stage to be used as a supplementary carbon source for biological denitrification to improve the denitrification efficiency.
According to the method for recycling the hydrothermal solution of the excess sludge, the effectiveness of the hydrothermal solution carbon source is improved by introducing the catalyst for inhibiting the formation of the Maillard reaction in the hydrothermal process of the sludge; in addition, the hydrothermal solution is pretreated by soil leaching, the soil intercepts the high molecular organic matters and the nitrogen and phosphorus substances in the hydrothermal solution, the content of the leached soil organic matters and the nitrogen and phosphorus is improved, the leached soil organic matters and the nitrogen and phosphorus can be used as a soil conditioner, the Maillard product substances and the nitrogen and phosphorus concentration in the leaching solution are obviously reduced, and the leached solution can be used as an effective carbon source for biological denitrification of sewage.
The invention provides a method for recycling hydrothermal solution of excess sludge, which comprises the steps of carrying out hydrothermal treatment on the excess sludge, carrying out soil leaching and interception on nitrogen and phosphorus in the hydrothermal solution and humified Maillard products to obtain nutrient substances in soil, wherein low-molecular organic matters in the leaching solution can be used as a supplementary carbon source for biological denitrification of sewage.
The invention has the following beneficial effects:
(1) the catalyst is used in the hydrothermal process of the residual sludge, so that the Maillard reaction in the hydrothermal process can be inhibited, the formation of macromolecular humic substances is reduced, and favorable conditions are provided for the hydrothermal solution as a denitrification carbon source.
(2) Heavy metals possibly contained in the residual sludge are mainly transferred and stabilized to the biochar in the hydrothermal process, and the problem of possible heavy metal pollution in the hydrothermal liquid recycling application process is effectively avoided.
(3) The nitrogen and phosphorus in the hydrothermal solution and the high-molecular organic matter are pretreated in a soil leaching mode, no additional medicament is needed to be added, the hydrothermal solution can be recycled for soil improvement, the problem of heavy metal pollution when the residual sludge is directly used for soil improvement is solved, and the nitrogen and phosphorus load when the hydrothermal solution is used as a denitrification carbon source is reduced.
Drawings
FIG. 1 is a process diagram of a method for hydrothermal liquid resource utilization of sludge.
Detailed Description
In order to make the present invention more comprehensible, preferred embodiments are described in detail for clear and complete description of technical solutions in the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
A hydrothermal liquid resource utilization method for excess sludge comprises the following steps:
step 1): adding a catalyst into the residual sludge, and performing hydrothermal reaction in a closed reactor to obtain biochar and hydrothermal liquid;
step 2): pretreating the hydrothermal solution by soil leaching, wherein nitrogen and phosphorus in the hydrothermal solution and high-molecular organic matters are trapped by soil, and leaching solution is obtained at the same time;
step 3): the leached soil is used as a soil conditioner, and the leachate is recycled to sewage treatment and used as a biological denitrification carbon source.
The water content of the sludge in the step 1) of the invention is 85-98%, the total organic matter concentration is 5-150 g/L, and the catalyst comprises sulfuric acid, citric acid and FeCl2、FeCl3The hydrothermal reaction temperature is 140-0And C, performing hydrothermal reaction for 0.5-8 h, wherein the closed reactor is a temperature-resistant, pressure-resistant and corrosion-resistant closed reactor, and an anti-corrosion lining layer is arranged inside the closed reactor.
After the hydrothermal reaction in the step 1) of the invention is finished, the reactor is cooled to room temperature, the hydrothermal mixed solution is centrifuged to respectively obtain a liquid hydrothermal solution and solid biochar, and the COD of the hydrothermal solution is 5-200 g/L.
One or two of the catalysts, namely sulfuric acid and citric acid, are selected and mixed in the step 1), the adding amount of the sulfuric acid is 0.001-0.01 mol/g VSS, the adding amount of the citric acid is 0.001-0.15 mol/g VSS, and when the sulfuric acid and the citric acid are mixed for use, the molar ratio of the sulfuric acid to the citric acid is 1:0.1-0.1: 10; with the use of catalyst FeCl2And FeCl3One or a mixture of the two is selected，FeCl2The addition amount of FeCl is 5-100 mg of Fe/gVSS3The addition amount of (b) is 10-150 mg Fe/gVSS, and when the two are mixed for use, FeCl2With FeCl3The mass ratio of 1: 0.2-0.1: 1. and fully stirring and mixing the residual sludge and the catalyst before the hydrothermal reaction. The biochar obtained by the hydrothermal reaction can be used as an adsorbent, a catalyst and a solid fuel.
The soil in the step 2) of the invention is saline-alkali soil and other barren soil, soil with reduced soil fertility after crop rotation, etc., the leaching adopts a filter tank form, the soil is used as a filter tank filter material, hydrothermal liquid is uniformly sprayed from the surface of the filter tank, and the volume load is 1-20 m3/(m2D), in order to ensure that the high molecular organic substances and nitrogen and phosphorus substances are fully intercepted in the soil, the mass ratio of the hydrothermal solution to the soil is 0.3:1-2:1, the leaching solution is the solution leached by the soil, when the concentration of total nitrogen, total phosphorus and organic substances in the leaching solution is obviously improved, the soil leaching solution is considered to be saturated, the leaching is stopped, and the soil filter material is replaced.
According to the invention, the soil conditioner in the step 2), namely the soil serving as the filter material in the step 2) is taken out from the filter after being saturated, and then returned to the soil to be mixed with the native soil, so that the fertility of the native soil is improved. The leaching solution is refluxed to the front end of the inlet water of a sewage treatment plant or to the biological denitrification and denitrification stage to be used as a supplementary carbon source for biological denitrification to improve the denitrification efficiency.
Example 1
A method for sludge hydrothermal liquid resource utilization comprises the following steps:
500 m of excess sludge is produced every day by a certain sewage treatment plant3The water content is 92 percent, the total organic matter concentration is 7 g/L, the total organic matter content is 3500 kg, and the catalyst selects sulfuric acid, citric acid and FeCl3Wherein the adding amount of the sulfuric acid and the citric acid is 0.01 mol/g VSS, the molar ratio of the sulfuric acid to the citric acid is 1:1, and FeCl is added3Is added in an amount of 200 kg, i.e. about 20mg Fe/gVSS. Mechanically stirring the catalyst and the excess sludge for 2 hours, fully mixing, and then carrying out hydrothermal reaction in a closed anticorrosive reaction kettle at the reaction temperature of 200 DEG C0And C, the reaction time is 3 h. After the reaction is finished, naturally cooling to room temperature, and performing centrifugal separation on the hydrothermal mixed solution to respectively obtain a liquid-phase hydrothermal liquid and solid-phase biochar, wherein the solid-phase biochar is used for burning solid fuels.
Resource utilization of hydrothermal solution: after hydrothermal reaction, the volume of hydrothermal solution is about 380m3The COD of the hydrothermal solution is 6.5 g/L, the total nitrogen concentration is 355 mg/L, the ammonia nitrogen concentration is 280 mg/L, the total phosphorus concentration is 45mg/L, and the absorbance of the Maillard substance represented by UV420 is 1.6. 2500kg of saline-alkali soil is taken as a filter material of the filter, hydrothermal liquid is uniformly sprayed from the surface of the filter, and the volume load is 10 m3/(m2D), after the hydrothermal solution is subjected to leaching, the total nitrogen, the ammonia nitrogen, the total phosphorus, the COD and the UV420 in the leaching solution are respectively 170 mg/L, 82 mg/L, 8mg/L, 5.5 mg/L and 0.6 respectively. And when the concentration of organic matters and total nitrogen is remarkably improved, judging that the soil leaching is saturated, stopping leaching, replacing the soil filter material, and backfilling the saturated soil filter material to the original soil for soil improvement.
Mixing the leachate with sewage inlet water, wherein the volume ratio of the leachate to the sewage inlet water is 1: 14, namely the leachate is diluted by 15 times, the COD in the inlet water can be improved by 367 mg/L, the denitrification effect is compared with that of a control group without the leachate, the outlet water TN of the control group is 28mg/L, the outlet water TN of an experimental group is 18 mg/L, and the addition of the leachate can effectively improve the biological denitrification effect.
Example 2
Adding catalyst citric acid and FeCl into residual sludge with water content of 96%2The amounts of addition were 0.005mol/gVSS and 50 mg/gVSS, respectively. Mechanically stirring the catalyst and the residual sludge for 2.5 h, fully mixing, and performing hydrothermal reaction in a closed anticorrosive reaction kettle. The reaction temperature is 180 DEG0And C, the reaction time is 3 h. And after the reaction is finished, naturally cooling to room temperature, and performing centrifugal separation on the hydrothermal mixed solution to respectively obtain a liquid-phase hydrothermal solution A and solid-phase biochar, wherein the solid-phase biochar is used as the persulfate activator. Treating the same sludge under the same hydrothermal reaction condition without adding any catalyst, and centrifuging after hydrothermal treatment to obtain hydrothermal solution B. The properties of hydrothermal solutions A and B are compared as shown in Table 1 below.
TABLE 1 comparison of the properties of hydrothermal solution A and hydrothermal solution B (unit: mg/L)
Figure 118374DEST_PATH_IMAGE002
As can be seen from table 1, when the catalyst was added, the SCOD in hydrothermal solution a was higher than that in hydrothermal solution B, indicating that more organic substances were dissolved out, and the VFAs having a lower molecular weight were higher in content, indicating that they were more easily utilized by microorganisms. In addition, although the TN content of hydrothermal solution A and that of hydrothermal solution B are similar, the DON content of hydrothermal solution A is lower than that of hydrothermal solution B, and when the DON is reused for sewage denitrification, deaminization reaction needs to be carried out to remove the DON, so that the effect of using the hydrothermal solution for sewage biological denitrification is influenced when the DON content is high. And after the catalyst is added, the content of humus substances in the hydrothermal solution is reduced, and the humus substances are generally macromolecular substances and are difficult to be used as biological denitrification carbon sources. From this, it is found that the properties of the hydrothermal solution are more favorable for use as a carbon source for biological denitrification after the catalyst is added.
Leaching hydrothermal solution A to the acid red soil poor in nutrition, uniformly spraying hydrothermal solution from the surface of the filter tank, and uniformly spraying hydrothermal solution from the surface of the filter tank with the volume load of 8m3/(m2D), continuously leaching for 1 month. After the hydrothermal solution is subjected to leaching, the SCOD of the leaching solution is 3100mg/L, the TN is 65mg/L, the DON is 16mg/L, the VFA is 445mg/L, and the HAs is 120mg/L, so that large amount of macromolecular HAs and organic nitrogen substances are trapped. And (3) performing denitrification nitrogen removal efficiency comparison on the hydrothermal solution A and the leachate, and respectively diluting the hydrothermal solution A and the leachate until the COD is 400mg/L and the concentration of the nitrate and the nitrogen of the inlet water is 40 mg/L, wherein the nitrate and the nitrogen removal rate of the hydrothermal solution A can be maintained at about 76 percent, and the nitrate and the nitrogen removal rate of the leachate is as high as more than 95 percent. After the soil is leached for 1 month, the TOC of the soil is increased from 6mg/g soil to 12mg/g soil, the total nitrogen is increased from 42mg/g soil to 150mg/g soil, the total phosphorus is increased from 30mg/g soil to 70mg/g soil, the soil fertility is improved, and the soil can be used for soil improvement after being recycled to original soil.

Claims (10)

1. A hydrothermal resource utilization method of excess sludge is characterized by comprising the following steps:
step 1): adding a catalyst into a closed reactor containing sludge, and carrying out hydrothermal reaction to obtain biochar and hydrothermal liquid;
step 2): pretreating the hydrothermal solution by soil leaching, wherein nitrogen and phosphorus in the hydrothermal solution and high-molecular organic matters are trapped by soil, and leaching solution is obtained at the same time;
step 3): the leached soil is used as a soil conditioner, and the leachate is recycled to sewage treatment and used as a biological denitrification carbon source.
2. The hydrothermal resource utilization method of excess sludge according to claim 1, wherein the water content of the sludge in the step 1) is 85-98%, and the total organic matter concentration is 5-150 g/L.
3. The hydrothermal recycling method of excess sludge in claim 1, wherein the catalyst in step 1) comprises sulfuric acid, citric acid, and FeCl2、FeCl3One or more of (a).
4. The method for hydrothermal recycling of excess sludge according to claim 3, wherein the catalyst in step 1) is sulfuric acid and citric acid, one or a mixture of sulfuric acid and citric acid, the amount of sulfuric acid is 0.001-0.01 mol/g VSS, the amount of citric acid is 0.001-0.15 mol/g VSS, and when the sulfuric acid and the citric acid are used in a mixture, the molar ratio of the sulfuric acid to the citric acid is 1:0.1-0.1: 10.
5. The hydrothermal recycling method of excess sludge according to claim 3, wherein the catalyst in step 1) is FeCl catalyst2And FeCl3One or a mixture of the two is selected, FeCl2The addition amount of FeCl is 5-100 mg of Fe/gVSS3The addition amount of (b) is 10-150 mg Fe/gVSS, and when the two are mixed for use, FeCl2With FeCl3The mass ratio of 1: 0.2-0.1: 1.
6. the method for hydrothermal recycling of excess sludge as claimed in claim 1, wherein the hydrothermal reaction temperature in step 1) is 140-0C, the hydrothermal reaction time is 0.5-8 h.
7. The hydrothermal recycling method of excess sludge according to claim 1, wherein the closed reactor in step 1) is a temperature-resistant, pressure-resistant and corrosion-resistant closed reactor, and an anti-corrosion lining is arranged inside the closed reactor.
8. The method for hydrothermal recycling of excess sludge according to claim 1, wherein after the hydrothermal reaction in step 1) is completed, the reactor is cooled to room temperature, the hydrothermal mixed solution is centrifuged to obtain a liquid hydrothermal solution and a solid biochar, respectively, and the hydrothermal solution has a COD of 5-200 g/L.
9. The method for recycling hydrothermal solution of excess sludge according to claim 1, wherein the soil in the step 2) is barren soil, leaching is performed in a filter tank mode, the soil is used as a filter material of the filter tank, the hydrothermal solution is uniformly sprayed from the surface of the filter tank, and the volume load is 1-20 m3/(m2D), the mass ratio of the hydrothermal solution to the soil is 0.3:1-2:1, and the leaching solution is the liquid leached by the soil.
10. The method for hydrothermal recycling of excess sludge according to claim 1, wherein the soil conditioner of step 3), that is, the soil used as the filter material in step 2), is taken out of the filter, returned to the soil, and mixed with the native soil to improve the fertility of the native soil; the leaching solution is refluxed to the front end of the inlet water of a sewage treatment plant or to the biological denitrification and denitrification stage to be used as a supplementary carbon source for biological denitrification to improve the denitrification efficiency.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115140911A (en) * 2022-06-27 2022-10-04 中国科学院兰州化学物理研究所 Preparation and application of biomass organic acid red mud dealkalizing agent

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CN106433713A (en) * 2016-11-01 2017-02-22 新疆大学 Sludge pyrolysis method adopting biomass adding
CN108558162A (en) * 2018-04-12 2018-09-21 大连理工大学 A kind of method of excess sludge hydrothermal carbonization liquid recycling
CN110114317A (en) * 2016-10-27 2019-08-09 西安大略大学 The hydrothermal liquefaction collaboration processing of the wastewater sludge and lignocellulose biomass of co-production for biogas and bio oil

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Publication number Priority date Publication date Assignee Title
CN106047384A (en) * 2016-06-03 2016-10-26 浙江科技学院 Method for preparing hydrothermal biological carbon with traditional Chinese medicine residues and application thereof
CN110114317A (en) * 2016-10-27 2019-08-09 西安大略大学 The hydrothermal liquefaction collaboration processing of the wastewater sludge and lignocellulose biomass of co-production for biogas and bio oil
CN106433713A (en) * 2016-11-01 2017-02-22 新疆大学 Sludge pyrolysis method adopting biomass adding
CN108558162A (en) * 2018-04-12 2018-09-21 大连理工大学 A kind of method of excess sludge hydrothermal carbonization liquid recycling

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115140911A (en) * 2022-06-27 2022-10-04 中国科学院兰州化学物理研究所 Preparation and application of biomass organic acid red mud dealkalizing agent

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