CN106517715B - A method of excess sludge anaerobic fermentation and acid production is strengthened in pretreatment - Google Patents
A method of excess sludge anaerobic fermentation and acid production is strengthened in pretreatment Download PDFInfo
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- CN106517715B CN106517715B CN201610907697.XA CN201610907697A CN106517715B CN 106517715 B CN106517715 B CN 106517715B CN 201610907697 A CN201610907697 A CN 201610907697A CN 106517715 B CN106517715 B CN 106517715B
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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
- C02F3/00—Biological treatment of water, waste water, or sewage
- C02F3/34—Biological treatment of water, waste water, or sewage characterised by the microorganisms used
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- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12P—FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
- C12P7/00—Preparation of oxygen-containing organic compounds
- C12P7/40—Preparation of oxygen-containing organic compounds containing a carboxyl group including Peroxycarboxylic acids
- C12P7/52—Propionic acid; Butyric acids
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- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12P—FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
- C12P7/00—Preparation of oxygen-containing organic compounds
- C12P7/40—Preparation of oxygen-containing organic compounds containing a carboxyl group including Peroxycarboxylic acids
- C12P7/54—Acetic acid
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/105—Phosphorus compounds
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/16—Nitrogen compounds, e.g. ammonia
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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
- C02F2305/00—Use of specific compounds during water treatment
- C02F2305/06—Nutrients for stimulating the growth of microorganisms
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Abstract
The present invention provides a kind of methods that excess sludge anaerobic fermentation and acid production is strengthened in pretreatment, it passes through free nitrous acid and rhamnolipid combined pretreatment, the method comprises the following steps: removing supernatant after being then allowed to stand, staying sludge spare Step 1: cleaned sludge three times with tap water；Step 2: utilizing sludge described in free nitrous low-kappa number；Step 3: rhamnolipid is added into the pretreated sludge of free nitrous acid carries out producing volatile fatty acid by anaerobic fermentation.The best fermentation and acid time is greatly shortened, the sour energy consumption of production and cost is greatly saved in this, obtaining volatile fatty acid is mainly propionic acid and acetic acid, the fermentation liquid of this enrichment acetic acid and propionic acid can be used as additional carbon and be added to improve Nitrogen/Phosphorus Removal in sewage, have certain reference value to the expense and raising return rate that reduce excess sludge resource utilization.
Description
Technical field
The present invention relates to organic solid castoff resource utilization field more particularly to a kind of free nitrous acid and rhamnose
The method of rouge combined pretreatment reinforcing excess sludge anaerobic fermentation and acid production.
Background technique
Sewage treatment plant both domestic and external mostly uses activated sludge technology, however this technology can inevitably generate a large amount of remain
Remaining sludge, stabilizes it and the expense of minimizing has been up to the 60% of entire sewage treatment plant's operating cost.To excess sludge
Inappropriate processing disposal options will cause serious environmental problem, such as contaminant water, soil, air etc. can also therefore prestige
Coerce human health.Excess sludge is handled by anaerobic fermentation, not only can be reduced sludge secondary pollution caused by environment, but also can be real
The recycling of existing resource, the volatile fatty acid of generation can be used as the water inlet that excellent additional carbon adds sewage treatment plant, with
Improve denitrogenation dephosphorizing efficiency.
Anaerobic fermentation includes dissolution, hydrolysis, acidification and four steps of methanation, is needed to improve the yield of volatile fatty acid
The efficiency of dissolution, hydrolysis and acidification is improved, while inhibiting the generation of methanation.To have reached a large amount of preprocess methods of this purpose
Through being attempted, including ultrasound, microwave, ozone and soda acid etc..Although these preprocess methods achieve certain effect,
It is they or the higher Energy input of needs or needs largely investment chemical agent, can also has an adverse effect to environment, because
This is difficult to utilize on a large scale.Free nitrous acid can be generated by the nitrosation reaction of anaerobic digestion solution, be a kind of renewable
With the chemical substance of low cost, the dissolution and hydrolysis of sludge can be effectively facilitated.However it is pretreated with free nitrous acid
Sludge, which carries out anaerobic fermentation, can still have a small amount of methanation reaction.Rhamnolipid is a kind of efficient, environmental protection and cheap life
Object surfactant, can effectively inhibit the activity of methanogen in anaerobic fermentation, but promote organic matter dissolution and
Hydrolysis aspect is barely satisfactory.Therefore, the pretreated sludge of free nitrous acid and rhamnolipid joint are carried out anaerobic fermentation may
The yield of volatile fatty acid can be effectively improved.
Summary of the invention
The main purpose of the present invention is to provide a kind of free nitrous acid and rhamnolipid combined pretreatment to strengthen remaining dirt
The method of mud anaerobic fermentation and acid production improves efficiency of sludge treatment, saves resource, saves and produces sour cost, improves energy utilization rate.
To achieve the above object, the present invention provides it is a kind of pretreatment strengthen excess sludge anaerobic fermentation and acid production method,
It is characterized in that, it is by free nitrous acid and rhamnolipid combined pretreatment, the method comprises the following steps:
Step 1: being cleaned sludge three times with tap water, supernatant is removed after being then allowed to stand, stays sludge spare；
Step 2: utilizing sludge described in free nitrous low-kappa number；It is generated by the nitrosation reaction of anaerobic digestion solution, is
A kind of renewable and inexpensive chemical substance can be effectively facilitated the dissolution and hydrolysis of sludge；
Volatilization is produced Step 3: rhamnolipid is added into the pretreated sludge of free nitrous acid and carries out anaerobic fermentation
Property fatty acid；Combine the activity that rhamnolipid inhibits methanogen on the basis of step 2.
Preferably, it in order to separate sufficiently, in said step 1, needs to take upper layer after standing 24 hours under 4 DEG C of environment
Clear liquid.
Preferably, the pretreatment time in step 2 is 1-2 days；
Preferably, it is 0.13~0.81mg/mL that the free nitrous acid concentration in sludge is kept in preprocessing process, optimal
Good concentration is 0.67mg/mL.
Preferably, free nitrous acid concentration can be obtained by the way that sodium nitrite is added.
Preferably, the rhamnolipid concentration being added in the step 3 is 0.04g/g-TSS.
Preferably, the anaerobic fermentation time in the step 3 is 10 days.
Preferably, using removing oxygen and filling nitrogen to reaction vessel and realize anaerobic fermentation in constant temperature oscillator.
Preferably, in step 3, the fermentation liquid of enrichment acetic acid and propionic acid is obtained after anaerobic fermentation, it can be as additional
Carbon source is added to improve Nitrogen/Phosphorus Removal in sewage, to improve raw material availability, is reduced costs.
The beneficial effect of above-mentioned technical proposal of the invention is:
Above scheme, using when free nitrous acid and rhamnolipid Combined Treatment sludge by the best fermentation and acid time significantly
Shorten, the sour energy consumption of production and cost is greatly saved in this, and obtaining volatile fatty acid is mainly propionic acid and acetic acid, this enrichment acetic acid and
The fermentation liquid of propionic acid can be used as additional carbon and be added to improve Nitrogen/Phosphorus Removal in sewage, to reduction excess sludge recycling
The expense and raising return rate utilized has certain reference value.
Detailed description of the invention
Fig. 1 is the free influence schematic diagram of nitrous acid and rhamnolipid and fermentation time to volatile fat acid yield；
Fig. 2 free influence of nitrous acid and rhamnolipid to volatile fat acid constituents when being fermentation 3 days.
Specific embodiment
To keep the technical problem to be solved in the present invention, technical solution and advantage clearer, below in conjunction with attached drawing and tool
Body embodiment is described in detail.
The present invention provides a kind of methods that excess sludge anaerobic fermentation and acid production is strengthened in pretreatment, which is characterized in that it is logical
Free nitrous acid and rhamnolipid combined pretreatment are crossed, the method comprises the following steps:
Step 1: being cleaned sludge three times with tap water, supernatant is removed after being then allowed to stand, stays sludge spare；
Step 2: utilizing sludge described in free nitrous low-kappa number；It is generated by the nitrosation reaction of anaerobic digestion solution, is
A kind of renewable and inexpensive chemical substance can be effectively facilitated the dissolution and hydrolysis of sludge；
Volatilization is produced Step 3: rhamnolipid is added into the pretreated sludge of free nitrous acid and carries out anaerobic fermentation
Property fatty acid；Combine the activity that rhamnolipid inhibits methanogen on the basis of step 2；
Free nitrous acid and rhamnolipid are reagent treatment that is cheap and being easy to obtain, and two kinds of reagent treatments are combined and made
With passing through complementary efficient, the low-cost processes realized to sludge in reaction mechanism.
Specifically, the present invention provides specific pretreatment time in order to which the pretreating effect guaranteed in step 2 can be up to standard
And free nitrous acid concentration, i.e. pretreatment time in step 2 is 1-2 days, keeps free in sludge in preprocessing process
Nitrous acid concentration is 0.13~0.81mg/mL, and most excellent concentration is 0.67mg/mL, and obtains raw material for convenience, is reduced pre-
Processing cost can obtain free nitrous acid concentration by the way that sodium nitrite is added.
Specifically, The present invention gives specific mouse in order to which the pretreatment guaranteed in step 3 can reach requirement effect
Lee's glycolipid concentration requires, i.e., the rhamnolipid concentration being added in the described step 3 is 0.04g/g-TSS, in order to guarantee that fermentation is filled
Point, the preferred time of specifically fermenting is given, i.e., the anaerobic fermentation time of the described step 3 kind is 10 days, and can be used
Oxygen and filling nitrogen is gone to reaction vessel and realizes anaerobic fermentation in constant temperature oscillator, implementation is convenient, strong operability.
More specifically, in step 3, the fermentation liquid of enrichment acetic acid and propionic acid is obtained after anaerobic fermentation, it can be as outer
Add carbon source to be added to improve Nitrogen/Phosphorus Removal in sewage, to improve raw material availability, reduces costs.
The present invention has carried out comparative test, pretreated result such as Fig. 1-2 institute herein in connection with various parameters and condition variation
Show, from Fig. 1 it is apparent that the addition of free nitrous low-kappa number and rhamnolipid improves the production of volatile fatty acid
Amount.Individually free nitrous low-kappa number and the addition of individual rhamnolipid respectively obtain 162.10 and 210.52mg COD/g
The volatile fat acid yield of VSS is the 2.49 and 3.23 of the volatile fat acid yield of sludge without any processing respectively
Times.When free nitrous acid and rhamnolipid Combined Treatment, as free nitrous low-kappa number concentration rises to from 0.13mg/L
The yield of 0.67mg/L, volatile fatty acid are increased to 352.62mg COD/g VSS by 225.55, and yield at this time is respectively
Individually free nitrous acid, independent rhamnolipid and 2.13,1.64 and 5.542 times when not doing any processing.And free nitrous acid
When concentration rises to 0.81mg/L from 0.67mg/L, the concentration of volatile fatty acid is not significantly improved.Therefore it selects
The free nitrous low-kappa number of 0.67mg/L simultaneously adds the mode of rhamnolipid to improve the yield that sludge produces volatile fatty acid.This
Outside, maximum volatilization will be obtained when the free nitrous acid joint rhamnolipid of discovery 0.67mg/L handles excess sludge during the fermentation
Property aliphatic acid yield time shorten to 3 days, be significantly less than control group and other research reports, shorter fermentation time and higher
The sour efficiency of production the production cost of volatile fatty acid can be effectively reduced.
As can be seen from Figure 2, compared with when without any processing, rhamnolipid can promote the generation of propionic acid, and free nitrous acid
To the composition of volatile fatty acid almost without significantly affecting.For individual rhamnolipid and in combination free nitrous acid and
Rhamnolipid processing, propionic acid are most important volatile fat acid constituents (are greater than 40%), followed by acetic acid, isobutyric acid and different
Valeric acid.Although individual rhamnolipid improves the ratio of propionic acid, total volatile fat acid yield is not high enough.Free Asia
The ratio (total 71.86%) that propionic acid and acetic acid are not only increased when nitric acid and rhamnolipid Combined Treatment, also improves total
Volatile fat acid yield (352.26mgCOD/g VSS), being used for as additional carbon can be effective in sewage treatment plant
Improve denitrogenation dephosphorizing efficiency.
The method of excess sludge anaerobic fermentation and acid production is strengthened in the pretreatment of the technical program, utilizes free nitrous acid and sandlwood
The best fermentation and acid time is greatly shortened when glycolipid Combined Treatment sludge, the sour energy consumption of production and cost is greatly saved in this, obtains
Volatile fatty acid is mainly propionic acid and acetic acid, and the fermentation liquid of this enrichment acetic acid and propionic acid can be used as additional carbon and be added to sewage
In to improve Nitrogen/Phosphorus Removal, to reduce excess sludge resource utilization expense and improve return rate have certain reference price
Value.
The above is a preferred embodiment of the present invention, it is noted that for those skilled in the art
For, without departing from the principles of the present invention, several improvements and modifications can also be made, these improvements and modifications
It should be regarded as protection scope of the present invention.
Claims (6)
1. a kind of method that excess sludge anaerobic fermentation and acid production is strengthened in pretreatment, which is characterized in that its by free nitrous acid and
Rhamnolipid combined pretreatment, the method comprises the following steps:
Step 1: being cleaned sludge three times with tap water, supernatant is removed after being then allowed to stand, stays sludge spare；
Step 2: utilizing sludge described in free nitrous low-kappa number；
Volatility rouge is produced Step 3: rhamnolipid is added into the pretreated sludge of free nitrous acid and carries out anaerobic fermentation
Fat acid；
It is added in sewage using the fermentation liquid of enrichment acetic acid and propionic acid that the step 3 obtains as additional carbon de- to improve
Nitrogen phosphor-removing effect；
The rhamnolipid concentration being added in the step 3 is 0.04g/g-TSS；
In the step 2, it is 0.67mg/mL that the free nitrous acid concentration in sludge is kept in preprocessing process.
2. the method that excess sludge anaerobic fermentation and acid production is strengthened in pretreatment according to claim 1, which is characterized in that described
Pretreatment time in step 2 is 1-2 days.
3. the method that excess sludge anaerobic fermentation and acid production is strengthened in pretreatment according to claim 1, which is characterized in that described
The anaerobic fermentation time in step 3 is 10 days.
4. the method that excess sludge anaerobic fermentation and acid production is strengthened in pretreatment according to claim 1, which is characterized in that in institute
It states in step 1, needs to take supernatant liquor after standing 24 hours under 4 DEG C of environment.
5. the method that excess sludge anaerobic fermentation and acid production is strengthened in pretreatment according to claim 1, which is characterized in that in institute
It states in step 3, oxygen and filling nitrogen is gone to reaction vessel and realizes anaerobic fermentation in constant temperature oscillator.
6. the method that excess sludge anaerobic fermentation and acid production is strengthened in pretreatment according to claim 1, which is characterized in that in institute
It states in step 2, obtains free nitrous acid concentration by the way that sodium nitrite is added.
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| CN108793656B (en) * | 2018-05-25 | 2021-03-09 | 上海交通大学 | Method for improving purity of methane in biogas generated by anaerobic digestion of sludge |
| CN113185074B (en) * | 2021-04-12 | 2022-10-21 | 哈尔滨工业大学 | Method for promoting accumulation of sludge anaerobic fermentation short-chain fatty acids by combined pretreatment of free nitrous acid and calcium peroxide |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102796764A (en) * | 2012-08-06 | 2012-11-28 | 哈尔滨工业大学 | Method for producing acid through promoting anaerobic fermentation of residual sludge by virtue of rhamnolipid biosurfactant |
| CN104450805A (en) * | 2014-11-21 | 2015-03-25 | 湖南大学 | Short-chain volatile fatty acid and preparation method thereof |
| CN105238822A (en) * | 2015-10-10 | 2016-01-13 | 湖南大学 | Combined pretreatment method for producing short-chain volatile fatty acids by enhancing anaerobic fermentation of sludge |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102796764A (en) * | 2012-08-06 | 2012-11-28 | 哈尔滨工业大学 | Method for producing acid through promoting anaerobic fermentation of residual sludge by virtue of rhamnolipid biosurfactant |
| CN104450805A (en) * | 2014-11-21 | 2015-03-25 | 湖南大学 | Short-chain volatile fatty acid and preparation method thereof |
| CN105238822A (en) * | 2015-10-10 | 2016-01-13 | 湖南大学 | Combined pretreatment method for producing short-chain volatile fatty acids by enhancing anaerobic fermentation of sludge |
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