CN115947511A - Method for breaking sludge - Google Patents
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- CN115947511A CN115947511A CN202211710194.5A CN202211710194A CN115947511A CN 115947511 A CN115947511 A CN 115947511A CN 202211710194 A CN202211710194 A CN 202211710194A CN 115947511 A CN115947511 A CN 115947511A
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- 238000000034 method Methods 0.000 title claims abstract description 52
- 108091005508 Acid proteases Proteins 0.000 claims abstract description 25
- 102000057297 Pepsin A Human genes 0.000 claims description 28
- 108090000284 Pepsin A Proteins 0.000 claims description 28
- 229940111202 pepsin Drugs 0.000 claims description 28
- 238000000197 pyrolysis Methods 0.000 claims description 15
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- 230000007071 enzymatic hydrolysis Effects 0.000 claims description 4
- 238000006047 enzymatic hydrolysis reaction Methods 0.000 claims description 4
- 230000002378 acidificating effect Effects 0.000 claims description 3
- 102100037486 Reverse transcriptase/ribonuclease H Human genes 0.000 claims 1
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- 244000005700 microbiome Species 0.000 abstract description 8
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/40—Valorisation of by-products of wastewater, sewage or sludge processing
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- Treatment Of Sludge (AREA)
Abstract
The invention provides a method for breaking sludge, which comprises the steps of firstly adjusting the pH value of the sludge, then adding acid protease for enzymolysis, and then pyrolyzing the sludge after the enzymolysis. The invention adopts the method of combining acid protease with low heat to break the sludge, and the breaking rate of the sludge is up to more than 50 percent; the BOD/TCOD value of the sludge cracked by the method is more than or equal to 0.30, the requirement of biodegradability is met, the biodegradability of the sludge is effectively improved, the recessive growth of sludge microorganisms is promoted, and the in-situ reduction of the sludge is effectively realized.
Description
Technical Field
The invention belongs to the technical field of sludge treatment, and particularly relates to a method for breaking sludge.
Background
With the recent year-by-year increase of urban sewage discharge and treatment capacity in China, sludge is continuously generated, and not little pressure is brought to urban environment protection. According to statistics, the yield of wet sludge in 2019 in the whole country is up to 595 ten thousand tons, and if all municipal sewage is treated, the yield of sludge exceeds 840 ten thousand tons, which accounts for about 3 percent of total solid waste in the whole country. Besides a large amount of water, the sludge also contains a large amount of toxic components which are difficult to degrade, such as organic matters, heavy metals, salts, pathogenic microorganisms, parasitic ova and the like, so that the recycling treatment is difficult and serious.
When part of microbial cells in the sludge are cracked or disintegrated, other microbes in the sludge can grow by utilizing nutrients dissolved in water, the process is called 'cell lysis-recessive growth', and the 'cell lysis-recessive growth' is used as a sludge in-situ reduction method with wide application prospect, and the cracked or disintegrated other microbial cells are consumed by utilizing the growth of the microbes in the sludge, so that the resource treatment of the sludge is realized. In this method, the microorganisms can only utilize other microorganisms that have been lysed or lysed, and cannot utilize other microorganisms that are intact, not lysed or lysed. Because of the protection of the microbial cell wall, the spontaneous lysis of the microbial cells is very difficult, so that the sludge needs to be artificially cracked, the microbial cells in the sludge are cracked or disintegrated, and conditions are created for the lysis-recessive growth of the microbes in the sludge.
Most of the current methods for destroying cell walls are physical methods, chemical methods and biological methods, but the physical methods easily cause the inactivation of macromolecular contents, the chemical methods are not environment-friendly and easily cause pollution, and the biological methods are distinguished from a plurality of methods for destroying cell walls. The prior art discloses a scheme for pretreating sludge by combining neutral protease and EDTA-2Na, which can effectively destroy cell walls of microorganisms in the sludge and improve the capacity of anaerobic fermentation and acid production of the sludge, but cannot effectively improve the biodegradability of the sludge.
Therefore, it is necessary to find a method for effectively breaking sludge and improving the biodegradability of sludge.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a method for breaking sludge, so that the sludge is broken efficiently, the biodegradability of the sludge is improved, and the recessive growth of sludge microorganisms is promoted.
The invention aims to provide a method for breaking sludge.
The invention realizes the above purpose by the following technical means:
the invention provides a method for breaking sludge, which sequentially adjusts the pH value of the sludge, carries out enzymolysis by acid protease and carries out pyrolysis on the sludge.
Preferably, the pH is adjusted to 1.5-5.0.
Preferably, the acid protease includes, but is not limited to, pepsin or an industrial acid protease.
Preferably, the activity of the acid protease is 3000-60000U/g.
Preferably, the ratio of the mass of the acid protease to the dry weight of the sludge is 0.12-0.2: 1. more preferably, the ratio of the mass of the acid protease to the dry weight of the sludge is 0.16-0.2: 1. most preferably 0.2.
Preferably, the temperature of the enzymolysis is 30-50 ℃.
Preferably, the enzymolysis time is 10-60 min.
Preferably, the enzymatic hydrolysis is carried out while stirring.
More preferably, the rotation speed of the stirring is 180 to 210rpm/min.
Preferably, the temperature of the pyrolysis is 60 to 90 ℃. Most preferably 70 deg.c.
Preferably, the pyrolysis time is 0.5 to 2.5 hours. Most preferably 1h.
Preferably, the pyrolysis is carried out in a sealed environment.
Preferably, the heating mode of the pyrolysis is water bath heating.
In the actual sludge treatment process, the enzymolysis conditions need to be adjusted according to different types of acid protease, so that the enzyme is in the optimal working environment.
As an alternative preferred embodiment, the method comprises the steps of firstly adjusting the pH value of the sludge to 2.0, then adding pepsin with the activity of 3000U/g, carrying out enzymolysis at 35 ℃ for 40min, and finally carrying out pyrolysis on the sludge after the enzymolysis.
As an alternative preferred embodiment, the method firstly adjusts the pH value of the sludge to 3.0, then adds industrial acid protease with the activity of 60000U/g, carries out enzymolysis for 60min at 45 ℃, and finally carries out pyrolysis on the sludge after the enzymolysis.
The invention has the following beneficial effects:
1. the method adopts the combination of acid protease and low heat to break the sludge, so that the breaking rate of the sludge is up to more than 50 percent, the biodegradability of the sludge is effectively improved while the sludge is broken, the sludge meets the requirement of biodegradability (BOD/TCOD is more than or equal to 0.30), the recessive growth of sludge microorganisms is promoted, and the in-situ reduction of the sludge is effectively realized.
2. According to the invention, the combination of acid protease and low-heat treatment is specifically selected, so that the problem of low cracking rate caused by the fact that protease used in the existing biological sludge cracking method is intercepted or bound by a sludge structure is effectively solved, the adsorption capacity of the sludge to the protease is effectively reduced, the activity of the protease is further improved, the hydrolysis performance of the protease is fully exerted, and the efficient utilization of the protease is realized.
Drawings
FIG. 1 shows the results of the sludge degradation rate test in example 1.
FIG. 2 shows the results of biochemical tests of sludge in example 1.
FIG. 3 shows the results of the sludge disintegration test in example 2, wherein the abscissa "enzyme addition amount (g/g dry sludge)" represents the ratio of pepsin mass to sludge dry weight.
FIG. 4 is the results of biochemical tests of sludge in example 2, wherein the abscissa "enzyme addition amount (g/g dry sludge)" represents the ratio of the amount of pepsin to the dry weight of sludge.
FIG. 5 shows the results of the sludge degradation rate test in example 3.
FIG. 6 shows the results of biochemical tests of sludge in example 3.
FIG. 7 shows the results of the sludge degradation rate test in example 5.
FIG. 8 shows the results of biochemical tests of sludge in example 5.
Detailed Description
The invention is further described with reference to the drawings and the following detailed description, which are not intended to limit the invention in any way. The reagents, methods and apparatus employed in the present invention are conventional in the art, except as otherwise indicated.
Unless otherwise indicated, reagents and materials used in the following examples are commercially available.
The model of the constant temperature type shaking table adopted in the embodiment is THZ-100; the model of the electric heating constant temperature water bath kettle is HWS-24; industrial acid proteases were purchased from Cangzhou summer Cheng Mei Biotechnology Inc.
The original sludge sample used in the embodiment of the invention is an experimental sludge sample obtained by settling the sewage in a secondary sedimentation tank of a sewage treatment plant in Guangzhou city at 4 ℃ for 24 hours and then removing the supernatant.
The water content, total Suspended Solids (TSS), total Chemical Oxygen Demand (TCOD), dissolved chemical oxygen demand (SCOD), biological Oxygen Demand (BOD), and biochemical index (BOD/TCOD) of the sludge sample were analyzed, and the results are shown in table 1.
TABLE 1
Wherein, the water content and Total Suspended Solids (TSS) are measured according to CJ/T221-2005, the Total Chemical Oxygen Demand (TCOD) and the dissolved chemical oxygen demand (SCOD) are measured by rapid spectrophotometry, and the Biological Oxygen Demand (BOD) is measured by rapid determination of a microorganism sensor (HJ/T86-2002).
The ratio BOD/TCOD of BOD to TCOD is an index for characterizing the biodegradability of the sludge, and the higher the BOD/TCOD ratio is, the stronger the biodegradability of the sludge is, i.e. the more easily biodegradable, and vice versa the less easily biodegradable. The degree of biodegradability of the sludge is generally judged according to the following criteria:
the biodegradation is good: BOD/TCOD is more than or equal to 0.45;
and (3) biodegradation: BOD/TCOD is more than or equal to 0.30 and less than 0.45;
difficult biodegradation: BOD/TCOD is more than or equal to 0.1 and less than 0.30;
non-biodegradable: BOD/TCOD is less than 0.1.
BOD/TCOD =0.30 is the lower limit of the biochemical degradability of the wastewater.
Therefore, as can be seen from Table 1, the sludge sample BOD/TCOD was less than 0.1, which was not biodegradable and was poor in biodegradability.
Example 1 method for sludge disruption
1. Experimental methods
S1, dividing 500g of sludge into five groups, respectively placing the five groups in 150mL conical flasks, adjusting the pH value to 2.0, adding 0.32g of pepsin (the ratio of the mass of the pepsin to the dry weight of the sludge is 0.16; the activity of the pepsin is 3000U/g), sealing the openings with a sealing film, and placing the openings in a shaking table with the temperature of 35 ℃ and the rpm of 200/min for enzymolysis for 40 minutes.
S2, pyrolysis: sealing the sludge after enzymolysis with tinfoil, heating in a 90 ℃ water bath, and taking out the sludge after 0.5, 1, 1.5, 2 and 2.5 hours respectively.
2. Results of the experiment
And (3) measuring the sludge cracking rate and BOD/TCOD values at 0.5, 1, 1.5, 2 and 2.5h, and measuring the cracking effect and biodegradability of the sludge.
Wherein, the sludge cracking rate is calculated by adopting the following formula:
in the formula: DD is the sludge disintegration rate,%; SCOD 0 And SCOD n SCOD values before and after sludge cracking are mg/L respectively; TCOD 0 The value is TCOD value before sludge disintegration, mg/L.
The measurement results are shown in table 2, and a graph of the sludge disintegration rate measurement results (shown in fig. 1) and a graph of the sludge biodegradability index (BOD/TCOD) measurement results (shown in fig. 2) are plotted at the same time.
TABLE 2
According to analysis on the cracking rate, the sludge cracking rate of the embodiment already reaches over 50% after heating for 0.5h, the sludge cracking rate is obviously improved to 64.5% when the heating is continued for 1h, the sludge cracking rate does not change greatly during the heating time of 1-2 h, and the sludge cracking rate does not increase to a small extent again until the heating time is 2.5h. Therefore, when the heating time is 1h, the sludge disintegration rate of the method reaches a better level.
From the analysis of the biochemical index BOD/TCOD value, the BOD/TCOD value of the sludge biochemical index in the embodiment reaches more than 0.30 when the heating time reaches 0.5h, the heating time rises from 0.5h to 1h, and the BOD/TCOD value is increased from 0.301 to 0.311, but the BOD/TCOD value is not obviously changed during the heating time from 1 to 2h, and the BOD/TCOD value is obviously increased during the 2h to 2.5h and is increased from 0.318 to 0.331. Therefore, the method for cracking the sludge obviously improves the BOD/TCOD value from 0.00166 of the original sludge to more than 0.3 after cracking, and shows that the method for cracking the sludge can obviously improve the biodegradability of the sludge and realize the in-situ degradation of the sludge, and has the advantages of high cracking rate and high cracking speed.
In summary, when the heating time is 1h, the sludge cracking rate and the biodegradability of the method reach better levels.
Example 2 method for breaking sludge
1. Experimental methods
S1, equally dividing 500g of sludge into five groups, respectively placing the five groups in 150mL conical flasks, adjusting the pH value to 2.0, and respectively adding 0.04g/g Amount of dry sludge 、0.08g/g Amount of dry sludge 、0.12g/g Amount of dry sludge 、0.16g/g Amount of dry sludge 、0.2g/g Amount of dry sludge The pepsin (namely the ratio of the mass of the pepsin to the dry weight of the sludge is 0.04, 0.08, 0.12, 0.16 and 0.2, which is equivalent to that the adding amount of the pepsin is 0.08g, 0.16g, 0.24g, 0.32g and 0.4g, and the activity of the pepsin is 3000U/g), and after being sealed by a sealing film, the mixture is placed in a shaking table with the temperature of 35 ℃ and the rpm/min for enzymolysis for 40 minutes.
S2, pyrolysis: sealing the sludge after enzymolysis with tinfoil, heating in a water bath kettle at 80 deg.C, and taking out the sludge after 2.5 hr.
2. Results of the experiment
The measurement results are shown in table 3, and a graph of the sludge disintegration rate measurement results (shown in fig. 3) and a graph of the sludge biodegradability index (BOD/TCOD) measurement results (shown in fig. 4) are plotted at the same time.
As can be seen from Table 3, the amount of pepsin is changed, the sludge degradation rate and the BOD/TCOD value are obviously changed, and the amount of pepsin has obvious influence on the sludge degradation; when the dosage of the pepsin reaches 0.16g/g Dry mud And then, the dosage of the pepsin is continuously increased, the sludge breaking rate can be continuously improved, but the improvement amplitude is not obvious. As can be seen, the dosage of the pepsin reaches 0.16g/g Dry mud Then, the sludge breaking rate of the method reaches a better level.
In addition, when the amount of pepsin is 0.08g/g Dry mud Increased to 0.12g/g Dry mud The BOD/TCOD value is obviously improved, when the dosage of the pepsin exceeds 0.12g/g Dry mud Thereafter, the amount of pepsin was increased, and the change in BOD/TCOD value was decreased.
In combination, when the amount of pepsin is 0.16g/g Dry mud In the method, the sludge cracking rate and the biodegradability reach better levels.
Example 3 method for sludge disruption
1. Experimental methods
S1, dividing 300g of sludge into 3 groups, respectively placing the 3 groups of sludge into 150mL conical flasks, adjusting the pH value to 2.0, adding 0.32g of pepsin (the ratio of the mass of the pepsin to the dry weight of the sludge is 0.16, and the activity of the pepsin is 3000U/g), sealing the openings with a sealing film, and placing the openings in a shaking table at 35 ℃ and 200rpm/min for enzymolysis for 40 minutes.
S2, pyrolysis: sealing the sludge after enzymolysis with tinfoil, heating in water bath at 60 deg.C, 70 deg.C and 80 deg.C respectively, and taking out the sludge after 1 hr.
2. Results of the experiment
The measurement results are shown in table 4, and a graph of the sludge disintegration rate measurement results (shown in fig. 5) and a graph of the sludge biodegradability index (BOD/TCOD) measurement results (shown in fig. 6) are plotted at the same time.
TABLE 4
The experimental result shows that the biochemical index BOD/TCOD value of the sludge can meet the biodegradable standard of more than or equal to 0.30 at any heating temperature. According to the analysis of the sludge breaking rate, when the heating temperature is increased from 60 ℃ to 70 ℃, the sludge breaking rate is obviously improved; while the sludge cracking rate is only slightly increased in the period of 70-80 ℃. It can be seen that when the heating temperature is 70 ℃, the sludge disintegration rate and the biodegradability of the method reach better levels.
Example 4 method for sludge disintegration
1. Experimental methods
S1, placing 100g of sludge in a 150mL conical flask, adjusting the pH value to 1.9, adding 0.32g of pepsin (equivalent to the ratio of the mass of the pepsin to the dry weight of the sludge is 0.16, and the activity of the pepsin is 3000U/g), sealing by using a sealing film, and then placing in a shaker at 35 ℃ and 200rpm/min for enzymolysis for 40 minutes.
S2, pyrolysis: sealing the sludge after enzymolysis with tinfoil, heating in a 70 ℃ water bath, and taking out the sludge after 1h.
2. Results of the experiment
The sludge breaking rate is 61.12 percent, and the BOD/TCOD value is 0.311.
The results of example 3 show that the method of the present invention has a better sludge degradation rate and BOD/TCOD value regardless of pH =1.9 or pH =2.0, indicating that the method of the present invention can efficiently degrade sludge and improve biodegradability of sludge.
Example 5 method for sludge disruption
In this example, the sludge used was the sludge sample obtained by allowing the sewage in the secondary sedimentation tank of the leaching Kau sewage treatment plant to stand at 4 ℃ for 24 hours and removing the supernatant. In order to maintain the biochemical properties of the sludge, the sludge needs to be used within 4 days.
The water content, total Suspended Solids (TSS), total Chemical Oxygen Demand (TCOD), dissolved chemical oxygen demand (SCOD), biological Oxygen Demand (BOD), and biochemical index (BOD/TCOD) of the sludge sample were analyzed, and the results are shown in table 5.
TABLE 5
1. Experimental methods
S1, placing 100g of sludge into a 150mL conical flask, adjusting the pH value to 3.0, adding 0.04-0.4 g of industrial acid protease (namely the ratio of the mass of the industrial acid protease to the dry weight of the sludge is 0.02-0.2, and the activity of the industrial acid protease is 60000U/g), sealing by using a sealing film, and then placing into a shaking table at 45 ℃ and 200rpm/min for enzymolysis for 60 minutes.
S2, pyrolysis: sealing the sludge after enzymolysis with tinfoil, heating in a 70 ℃ water bath, and taking out the sludge after 2.5h.
2. Results of the experiment
And (3) measuring the sludge cracking rate and BOD/TCOD value, and measuring the cracking effect and biodegradability of the sludge.
The measurement results are shown in table 6, and a graph of the sludge degradation rate measurement results (shown in fig. 7) and a graph of the sludge biodegradability index (BOD/TCOD) measurement results (shown in fig. 8) are plotted at the same time.
TABLE 6
As can be seen from Table 6, the amount of the industrial acidic protease is changed, the sludge degradation rate and the BOD/TCOD value are obviously changed, and the use amount of the industrial acidic protease has obvious influence on the sludge degradation and the biodegradability of the sludge; the dosage of the industrial acid protease is 0.16g/g Dry mud In the process, the cracking effect of the industrial acid protease on the sludge reaches a better level, and the standard of biodegradation is met.
Therefore, the sludge can meet the biodegradable condition through the sludge breaking by the industrial acid protease and the sludge breaking by the pepsin, but the cost of the industrial acid protease medicament is greatly reduced, and the method is a preferred scheme.
In conclusion, the method provided by the invention adopts the combination of acid protease and low heat to break the sludge, so that the breaking rate of the sludge is up to more than 50%, the biodegradability of the sludge is effectively improved, and the requirement of biodegradability (BOD/TCOD is more than or equal to 0.30) is met.
Comparative example 1
1. Experimental methods
According to the scheme of patent CN102583917B, and the optimal process condition is selected to crack the sludge.
100g of sludge (the sludge sample source is the same as that in example 1) is placed in a 150mL conical flask, EDTA-2Na is prepared into a 2.0g/mL solution, 0.4mL of EDTA-2Na (equivalent to the addition amount of 0.25 g/gTS) is added, 40mg of neutral protease (equivalent to the ratio of the mass of the neutral protease to the dry weight of the sludge of 20 mg/gTS) is added, a sealing film is used for sealing, and then the mixture is placed in a shaking table at 55 ℃ and 200rpm/min for enzymolysis for 2 hours.
2. Results of the experiment
After being cracked, the SCOD is 5420mg/L, the sludge cracking rate is 46.8 percent, and the BOD is 2180mg/L, but the BOD/TCOD is only 0.19, so the sludge is difficult to biodegrade and has poor biodegradability.
Comparative example 2 method for breaking sludge
1. Experimental methods
S1, placing 100g of sludge (the sludge sample is from the same source as the example 1) in a 150mL conical flask, adding 0.32g of neutral protease, sealing the conical flask with a sealing film, and then placing the conical flask in a shaking table at 55 ℃ and 200rpm/min for enzymolysis for 40min.
S2, sealing the sludge subjected to enzymolysis with tinfoil, heating in a 70 ℃ water bath, and taking out the sludge after 2.5 hours.
2. Results of the experiment
After disintegration, the SCOD is 2210mg/L, the sludge disintegration rate is 18.7 percent, the BOD is 982mg/L, and the BOD/TCOD is only 0.09, so the sludge is not biodegradable and has extremely poor biodegradability.
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.
Claims (10)
1. A method for breaking sludge is characterized in that the sludge is sequentially subjected to pH adjustment, acid protease enzymolysis and pyrolysis.
2. The method according to claim 1, wherein the pH is adjusted to 1.5 to 5.0.
3. The method of claim 1, wherein the acid protease comprises pepsin or an industrial acid protease.
4. The method according to claim 1, wherein the activity of the acid protease is 3000 to 60000U/g.
5. The method according to claim 1, wherein the ratio of the mass of the acidic protease to the dry weight of the sludge is 0.12 to 0.2:1.
6. the method of claim 1, wherein the temperature of the enzymatic hydrolysis is 30-50 ℃.
7. The method of claim 1, wherein the time for enzymatic hydrolysis is 10-60 min.
8. The method of claim 1, wherein the enzymatic hydrolysis is carried out with agitation.
9. The method of claim 1, wherein the pyrolysis temperature is 60 to 90 ℃.
10. The process according to claim 1, characterized in that the pyrolysis time is comprised between 0.5 and 2.5h.
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|---|---|---|---|---|
| CH657604A5 (en) * | 1982-08-06 | 1986-09-15 | Buchs Umwelttech Utb | Process for the anaerobic treatment of sewage sludge and apparatus for carrying out the process |
| DE10249081A1 (en) * | 2002-10-21 | 2004-04-29 | Volker Lenski | Simplified sewage sludge treatment comprises an enzyme treatment step, and optionally a peroxide treatment step at an acidic pH |
| CN102583917A (en) * | 2012-02-14 | 2012-07-18 | 江南大学 | Municipal sludge pretreatment method enhancing sludge anaerobic fermentation acid production |
| CN106830589A (en) * | 2017-02-04 | 2017-06-13 | 协赛(上海)生物科技有限公司 | A kind of method that sludge sour water solution extracts microbial amino acid |
| CN108609823A (en) * | 2018-03-30 | 2018-10-02 | 南方科技大学 | A kind of method of reinforcement sludge dewatering |
| CN108862992A (en) * | 2018-07-06 | 2018-11-23 | 沈阳航空航天大学 | A kind of method of the protease joint thermal pressure to sludge dewatering |
| CN111592209A (en) * | 2020-05-31 | 2020-08-28 | 浙江工业大学 | Method for promoting sludge dehydration by thermally activating calcium peroxide |
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2022
- 2022-12-29 CN CN202211710194.5A patent/CN115947511A/en active Pending
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| CH657604A5 (en) * | 1982-08-06 | 1986-09-15 | Buchs Umwelttech Utb | Process for the anaerobic treatment of sewage sludge and apparatus for carrying out the process |
| DE10249081A1 (en) * | 2002-10-21 | 2004-04-29 | Volker Lenski | Simplified sewage sludge treatment comprises an enzyme treatment step, and optionally a peroxide treatment step at an acidic pH |
| CN102583917A (en) * | 2012-02-14 | 2012-07-18 | 江南大学 | Municipal sludge pretreatment method enhancing sludge anaerobic fermentation acid production |
| CN106830589A (en) * | 2017-02-04 | 2017-06-13 | 协赛(上海)生物科技有限公司 | A kind of method that sludge sour water solution extracts microbial amino acid |
| CN108609823A (en) * | 2018-03-30 | 2018-10-02 | 南方科技大学 | A kind of method of reinforcement sludge dewatering |
| CN108862992A (en) * | 2018-07-06 | 2018-11-23 | 沈阳航空航天大学 | A kind of method of the protease joint thermal pressure to sludge dewatering |
| CN111592209A (en) * | 2020-05-31 | 2020-08-28 | 浙江工业大学 | Method for promoting sludge dehydration by thermally activating calcium peroxide |
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