CN109574434A - A method of strengthening excess sludge anaerobic digestion methane phase using alkaloid - Google Patents
A method of strengthening excess sludge anaerobic digestion methane phase using alkaloid Download PDFInfo
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- CN109574434A CN109574434A CN201811525475.7A CN201811525475A CN109574434A CN 109574434 A CN109574434 A CN 109574434A CN 201811525475 A CN201811525475 A CN 201811525475A CN 109574434 A CN109574434 A CN 109574434A
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- alkaloid
- sludge
- excess sludge
- mud
- methane phase
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
- C02F11/02—Biological treatment
- C02F11/04—Anaerobic treatment; Production of methane by such processes
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
- C02F11/12—Treatment of sludge; Devices therefor by de-watering, drying or thickening
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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
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E50/00—Technologies for the production of fuel of non-fossil origin
- Y02E50/30—Fuel from waste, e.g. synthetic alcohol or diesel
Abstract
The present invention provides a kind of methods for strengthening excess sludge anaerobic digestion methane phase using alkaloid, comprising: S1, precipitates excess sludge, is concentrated, obtaining pending mud；S2, inoculation mud and the resulting pending mud of step S1 are mixed to get fermenting mixture；S3, the resulting fermenting mixture of step S2 is mixed with alkaloid, is stirred evenly, carry out hydrolysed ferment after adjusting pH.The experimental results showed that adding the experimental group of alkaloid compared with control treatment (alkaloid is not added), final 20% or more anaerobically digested sludge shorter residence time, methane cumulative production improves 40% or more.The present invention can release the inhibiting effect of small molecular organic acid, and utilize its reproducibility in anaerobic sludge digestion initial phase using alkaloid, improve sludge hydrolytic rate and hydrolysis degree, and then improve anaerobic sludge digestion methane phase performance.Its is technically simple, easily operated, in the technological transformation that can be used for creating sewage plant and existing sewage plant.
Description
Technical field
The invention belongs to field of environment engineering technology, are related to a kind of utilization alkaloid reinforcing excess sludge anaerobic digestion production first
The method of alkane.
Background technique
In recent years, as China's town domestic sewage treatment scale constantly expands, urban wastewater treatment pressure is got worse.
And sludge is as the by-product in municipal sewage plant's biological treatment process, since its yield is big, harm is big, processing cost
Height is increasingly subject to the concern of people.If it cannot obtain effectively appropriate processing, serious pollution easily is caused to environment.Separately
Outside, sludge is handled using Anaerobic Biotechnology, is effectively reduced in sludge rich in organic matters such as polysaccharide, protein, lipids
The content of organic matter, and energy recovery is realized by way of methane phase.
However, in relatively slow hydrolysis acidification step is the important rate-limiting step of anaerobic sludge digestion.Because of sludge
In most of organic matter, such as polysaccharide and protein exist in the form of macromolecular, it is necessary to be decomposed into small organic molecule
It can be carried out hydrogenesis and acetogenesis and subsequent methanogenesis.Research is concentrated mainly on soda acid processing, ultrasonication, electrification at present
It learns in the means such as pretreatment and Grape berry, the hydrolysis acidification rate of Lai Tigao sludge.Although these technologies can be by cracking
Sludge wadding body discharges the modes such as organic matter intracellular and promotes sludge hydrolysis, acidification, but there is higher costs, complicated for operation, increase
The problems such as subsequent processing difficulty, it is difficult to really be promoted and applied.
Alkaloid has significant bioactivity as a kind of nitrogenous alkaline organic compound, can be combined formation with acid
Salts substances effectively release acid suppression existing for anaerobic sludge digestion early period.In addition, alkaloid has reproducibility, can increase
By force to the degradation capability of hardly degraded organic substance in sludge, and then promote the hydrolysis acidification process of sludge.The present invention is exactly in sludge
In anaerobic digestion process, using the reproducibility of alkaloid, certain organic matters in microbiological oxidation sludge are restored, especially difficult drop
Substance is solved, the Hydrolysis Acidification of sludge, and then reinforcement sludge anaerobic digestion methane phase process are accelerated.
Summary of the invention
For hydrolysis acidification rate in excess sludge anaerobic digestion is slow, degree is not high, the inferior technology of methane phase low efficiency is asked
Topic, the present invention provide a kind of method using alkaloid reinforcement sludge anaerobic digestion methane phase.
Present invention is primarily based on the reproducibilities of natural alkaloid, restore certain organic matters in microbiological oxidation sludge, especially
It is hard-degraded substance, accelerates the Hydrolysis Acidification of sludge；And its alkalescent is utilized, acid can be hydrolyzed with anaerobic sludge digestion
The organic acid that the change stage generates combines, and the acid effectively released in anaerobic digestion process inhibits, and makes hydrolysis acidification rate and degree
It significantly improves；Being formed by organic acid weak base salt can be utilized with slow release organic acid for subsequent methanogen, final to improve dirt
The performance of mud anaerobic digestion methane phase.
The purpose of the present invention is what is be achieved through the following technical solutions:
The present invention provides a kind of methods for strengthening excess sludge anaerobic digestion methane phase using alkaloid, are given birth to by addition
Alkaloids, the small molecular organic acid generated with anaerobic sludge digestion early period are combined generation salt, effectively releasing anaerobic sludge digestion
The acid generated in the process inhibits, and utilizes its reduction, enhances the degradation to hardly degraded organic substance in sludge, accelerates dirty
Muddy water solution acidification rate and process, and then improve the performance of subsequent anaerobic sludge digestion methane phase；Specifically comprise the following steps:
S1, excess sludge is precipitated, is concentrated, obtaining pending mud；
S2, inoculation mud and the resulting pending mud of step S1 are mixed to get fermenting mixture in proportion；
S3, the resulting fermenting mixture of step S2 is mixed in proportion with alkaloid, is stirred evenly, carry out water after adjusting pH
Hydrolysis and fermentation.
Preferably, in step S1, the solid content of the pending mud is 3%-5%；
In step S2, the volume ratio that the inoculation mud accounts for fermenting mixture is 10%-50%；The inoculation mud is at sewage
Manage the digested sludge of factory's anaerobic digester；The solid content of the inoculation mud is 3%-5%.If inoculum concentration is less than 10%, greatly
The period of anaerobic digestion is extended greatly, and anaerobic digestion reaction starting rate is slower；If inoculum concentration is too high, the anaerobism of sludge disappears
It is too low to change efficiency.If the solid content for being inoculated with mud is lower than 3%, anaerobic sludge digestion efficiency is too low；If solid content is higher than 5%,
Then during anaerobic sludge digestion, the mass-transfer efficiency of sludge is affected, and because of content of organics in digestion process
It is higher, lead to a large amount of accumulation of organic acid, toxic action is caused to microorganism, it is final to influence anaerobic digestion efficiency.
Preferably, in step S3, the alkaloid is one or more of matrine, choline and glycine betaine；
Concentration range of the alkaloid in fermenting mixture is 0.3-1.0mg/L.These three described alkaloids are in alkali
Property, its inhibiting effect can be released in conjunction with organic acid, improve bioactivity, and had preferable water-soluble.Choline has strong
Reproducibility, be the important component for constituting biological cell membrane, promote the metabolism of organic matter, transmethylase metabolism is with higher micro-
Bioactivity.Clinic, which shows that choline concentration is excessively high, can generate toxic action.Matrine equally has hypotoxicity, at low concentrations,
There is facilitation to microbial activity and metabolism.Glycine betaine plays a significant role biological nutrition metabolism, but if concentration
It is excessively high, there is bactericidal effect.Three kinds of alkaloids have bioactivity and Nutrition and Metabolism in certain concentration range important
Effect, but excessive concentration easily has an adverse effect to microorganism.Also, excessive concentration also will increase cost.
Preferably, in step S3, the pH range of the fermenting mixture is 6.8-7.2.
Preferably, in step S3, during the hydrolysed ferment, temperature control is 30-35 DEG C, fermentation time 20-
28 days.
Technical principle of the invention is as follows:
In the anaerobic sludge digestion initial stage, under the action of organic matter degradation bacteria and acid-producing bacteria, hydrolysis acid occurs for sludge
Change reaction, generates a large amount of various organic acids, lead to the pH rapid decrease in system, and low ph conditions system is unfavorable for methane phase
The metabolism of bacterium, to influence the performance of anaerobic sludge digestion methane phase；With the further degradation of itrogenous organic substance, ammonia is also gradually
It discharges into system, improves the pH value of system, promote the progress of anaerobic methane production process.And natural alkaloid, have weak
Alkalinity can form organic acid weak base salt in conjunction with organic acid, improve the acidic environment of system, to be subsequent methanogen
Metabolism better environment is provided；In addition, because alkaloid to the combination of organic acid, leads to the organic acid in system
Concentration reduces, and alleviates organic acid product to the Product inhibiton feedback effect of hydrolysis acidification, to accelerate the hydrolysis acid of sludge
Change rate and process；At the same time, the organic acid weak base salt that alkaloid and organic acid are formed, can delay under low-organic acid concentration
On The Drug Release organic acid thus will not influence the ultimate output of methane, because methanogenesis is with organic acid (acetic acid and butyric acid
Equal small molecular organic acids) it is what substrate carried out.Meanwhile alkaloid has reproducibility, can use it and restores microbiological oxidation dirt
Certain organic matters in mud, especially hardly degraded organic substance are conducive to the concentration of substrate for enhancing hydrolysis acidification bacterium, and then improve dirty
The rate and degree of mud hydrolysis acidification improve the performance of anaerobic sludge digestion methane phase.
To sum up, the addition of alkaloid can accelerate sludge hydrolysis, acidification rate, improve sludge hydrolysis, acidification degree, shorten dirty
The mud hydrolysis acidification period, and then effectively facilitate the methanation of sludge.
Compared with prior art, the invention has the following beneficial effects:
1, the present invention under lower processing cost, can effectively improve the hydrolysis acidification rate of sludge, promote sludge water
Acidizing degree is solved, shortens the sludge hydrolysis, acidification period, so that the anaerobic sludge digestion residence time be greatly decreased, while methane can be made
40% or more output increased.
2, alkaloid is easy degradation in anaerobic sludge digestion system, is unlikely to influence the subsequent processing disposition of sludge.
3, operation of the present invention method is simple, cost of investment is low, can greatly improve methane production, to be existing sludge digestion
The upgrading of processing system provides the choice of technology.
Specific embodiment
The present invention is described in detail combined with specific embodiments below.Following embodiment will be helpful to the technology of this field
Personnel further understand the present invention, but the invention is not limited in any way.It should be pointed out that the ordinary skill of this field
For personnel, without departing from the inventive concept of the premise, several changes and improvements can also be made.These belong to the present invention
Protection scope.
Embodiment 1
Sewage plant excess sludge concentration is taken to adjust solid content to 3%, will be derived from solid content in anaerobic digester is 5% inoculation
Mud is seeded in excess sludge according to percent by volume 10%, is uniformly mixed, alkaloid is added to according to the concentration of 0.3mg/L
It include matrine, choline, glycine betaine in alkaloid in fermenting mixture, ratio 1:1:1 adjusts pH to 6.8 after mixing
After be introduced into anaerobic digestor, after anaerobic digestion temperature is set as 30 DEG C, reaction 28 days, accumulation methane production is 2200ml/
L.Compared with the control treatment for being not added with alkaloid, anaerobically digested sludge shorter residence time 27% finally accumulates methane phase
Amount improves 43%.
Embodiment 2
Sewage plant excess sludge concentration is taken to adjust solid content to 4%, will be derived from solid content in anaerobic digester is 3% inoculation
Mud is seeded in excess sludge according to percent by volume 50%, is uniformly mixed, alkaloid is added to according to the concentration of 0.6mg/L
In fermenting mixture, the alkaloid of addition is choline, is introduced into anaerobic digestor after adjusting pH to 7.2 after mixing, detests
After oxygen digestion temperature is set as 35 DEG C, reaction 20 days, accumulation methane production is 2500ml/L.Place is compareed be not added with alkaloid
Reason is compared, anaerobically digested sludge shorter residence time 30%, and final methane production of accumulating improves 50%.
Embodiment 3
Sewage plant excess sludge concentration is taken to adjust solid content to 5%, will be derived from solid content in anaerobic digester is 4% inoculation
Mud is seeded in excess sludge according to percent by volume 30%, is uniformly mixed, alkaloid is added to according to the concentration of 1.0mg/L
In fermenting mixture, the alkaloid of addition is matrine, is introduced into anaerobic digestor after adjusting pH to 7.0 after mixing,
After anaerobic digestion temperature is set as 33 DEG C, reaction 25 days, accumulation methane production is 2350ml/L.Be not added with compareing for alkaloid
Processing is compared, anaerobically digested sludge shorter residence time 25%, and final methane production of accumulating improves 45%.
Embodiment 4
Sewage plant excess sludge concentration is taken to adjust solid content to 5%, will be derived from solid content in anaerobic digester is 3% inoculation
Mud is seeded in excess sludge according to percent by volume 20%, is uniformly mixed, alkaloid is added to according to the concentration of 0.6mg/L
In fermenting mixture, the alkaloid of addition is glycine betaine, is introduced into anaerobic digestor after adjusting pH to 7.0 after mixing,
After anaerobic digestion temperature is set as 35 DEG C, reaction 28 days, accumulation methane production is 2050ml/L.Be not added with compareing for alkaloid
Processing is compared, anaerobically digested sludge shorter residence time 25%, and final methane production of accumulating improves 40%.
Specific embodiments of the present invention are described above.It is to be appreciated that the invention is not limited to above-mentioned
Particular implementation, those skilled in the art can make a variety of changes or modify within the scope of the claims, this not shadow
Ring substantive content of the invention.In the absence of conflict, the feature in embodiments herein and embodiment can any phase
Mutually combination.
Claims (5)
1. a kind of method for strengthening excess sludge anaerobic digestion methane phase using alkaloid, which comprises the steps of:
S1, excess sludge is precipitated, is concentrated, obtaining pending mud；
S2, inoculation mud and the resulting pending mud of step S1 are mixed to get fermenting mixture in proportion；
S3, the resulting fermenting mixture of step S2 is mixed in proportion with alkaloid, is stirred evenly, hair is hydrolyzed after adjusting pH
Ferment.
2. the method according to claim 1 for being strengthened excess sludge anaerobic digestion methane phase using alkaloid, feature are existed
In in step S1, the solid content of the pending mud is 3%-5%；
In step S2, the volume ratio that the inoculation mud accounts for fermenting mixture is 10%-50%；The inoculation mud is sewage treatment plant
The digested sludge of anaerobic digester；The solid content of the inoculation mud is 3%-5%.
3. the method according to claim 1 for being strengthened excess sludge anaerobic digestion methane phase using alkaloid, feature are existed
In in step S3, the alkaloid is one or more of matrine, choline and glycine betaine；The alkaloid is fermenting
Concentration range in mixture is 0.3-1.0mg/L.
4. the method according to claim 1 for being strengthened excess sludge anaerobic digestion methane phase using alkaloid, feature are existed
In in step S3, the pH range of the fermenting mixture is 6.8-7.2.
5. the method that alkaloid according to claim 1 strengthens excess sludge anaerobic digestion methane phase, which is characterized in that step
In rapid S3, during the hydrolysed ferment, temperature control is 30-35 DEG C, and fermentation time is 20-28 days.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113307466A (en) * | 2020-12-03 | 2021-08-27 | 江南大学 | Method for accelerating starting of anaerobic digestion system for hot alkali pretreatment sludge |
| CN115010336A (en) * | 2022-06-27 | 2022-09-06 | 上海交通大学 | Method for producing methane through anaerobic digestion of sludge based on slow-release choline |
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| JPH0671296A (en) * | 1992-06-18 | 1994-03-15 | Ngk Insulators Ltd | Solid-liquid separation method for digested sludge |
| CN101085997A (en) * | 2006-06-09 | 2007-12-12 | 同济大学 | Method for promoting organic acid yield from sludge |
| CN101314783A (en) * | 2008-06-02 | 2008-12-03 | 江南大学 | Method for preparing volatile fatty acid with high solid concentration organic castoff heat-alkali preprocessing post anaerobic fermentation |
| CN103160546A (en) * | 2013-03-04 | 2013-06-19 | 同济大学 | Method for improving short-chain fatty acid produced by excess sludge through hot alkali combined pretreatment |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113307466A (en) * | 2020-12-03 | 2021-08-27 | 江南大学 | Method for accelerating starting of anaerobic digestion system for hot alkali pretreatment sludge |
| CN115010336A (en) * | 2022-06-27 | 2022-09-06 | 上海交通大学 | Method for producing methane through anaerobic digestion of sludge based on slow-release choline |
| CN115010336B (en) * | 2022-06-27 | 2023-10-20 | 上海交通大学 | Method for producing methane by sludge anaerobic digestion based on slow-release choline |
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