CN115072942B - Combined treatment process for aquatic product processing wastewater and domestic sewage - Google Patents
Combined treatment process for aquatic product processing wastewater and domestic sewage Download PDFInfo
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- CN115072942B CN115072942B CN202210873968.XA CN202210873968A CN115072942B CN 115072942 B CN115072942 B CN 115072942B CN 202210873968 A CN202210873968 A CN 202210873968A CN 115072942 B CN115072942 B CN 115072942B
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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
- C02F9/00—Multistage treatment of water, waste water or sewage
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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
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/001—Processes for the treatment of water whereby the filtration technique is of importance
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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
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/40—Devices for separating or removing fatty or oily substances or similar floating material
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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
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
- C02F1/444—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by ultrafiltration or microfiltration
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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
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
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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
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/5263—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using natural chemical compounds
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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
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
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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
- C02F2303/00—Specific treatment goals
- C02F2303/04—Disinfection
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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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- 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
- C02F3/30—Aerobic and anaerobic processes
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Abstract
The invention relates to the field of wastewater treatment, and discloses a combined treatment process of aquatic product processing wastewater and domestic sewage, which comprises the following steps: (1) Domestic sewage sequentially passes through a septic tank, a grid, a regulating tank, a hydrolysis acidification tank, an anaerobic tank, a contact oxidation tank, a sedimentation tank and a membrane bioreactor; (2) Conveying the sludge in the hydrolysis acidification tank to a sludge acidification tank; (3) treating the aquatic product processing wastewater by a grid and an oil removal tank; (4) Conveying the aquatic product processing wastewater treated by the oil removal tank and the mixed liquid in the sludge acidification tank to a mixed acidification tank for mixing; (5) Conveying the mixed solution in the mixed acidification tank to an ultrafiltration tank; (6) And conveying the concentrated water generated by the ultrafiltration process to a disinfection tank for disinfection treatment, and recovering the protein in the concentrated water. The process can rapidly recover the protein in the aquatic product processing wastewater, and simultaneously utilizes the nutrient substances of the excess sludge generated in the domestic sewage treatment process and the obtained protein to prepare the animal feed with rich nutrition.
Description
Technical Field
The invention relates to a wastewater treatment process, in particular to a combined treatment process of aquatic product processing wastewater and domestic sewage.
Background
With the continuous increase of fishery output in China, the fishery processing industry becomes a key link for the value increase of aquatic products, a large amount of washing and washing wastewater can be generated in the processing process of the aquatic products, substances such as amino acid, ammonia nitrogen and the like can be formed under the action of microorganisms in a water environment due to the abundant protein content in the aquatic product processing wastewater, and if the substances are discharged into the water body without being treated, the ammonia nitrogen concentration in the water body exceeds the standard, foul gas can be generated, and the environment is greatly damaged. And the discharge amount of the waste water generated in the aquatic product processing is unbalanced, the water quality fluctuation is large, and the prior art is difficult to effectively treat the waste water.
CN108483826A discloses a treatment process and a treatment apparatus for wastewater from aquatic product processing, which can effectively remove organic substances, nitrogen and phosphorus in wastewater from aquatic product processing by using a process such as a grating, anMBR, CWSBR, etc. to denitrify the wastewater. The aquatic product processing wastewater contains a large amount of fish protein resources, and the fish protein resources are directly used as pollutants to be treated, so that huge waste is generated.
WO2015022913A1 discloses how to recover protein from waste water during fish product processing by adjusting the pH of ground bleaching waste water or slime water to 4.5 to 5.5 to insolubilize water soluble proteins and then heating it to 30-90 ℃, however, although the protein in waste water can be efficiently recovered by pH adjustment and heating, the addition of large amounts of pH adjusting agents and large energy consumption are required.
How to recycle the protein in the aquatic product processing wastewater with high efficiency, and simultaneously, the discharge of the aquatic product processing wastewater meets the requirements, which becomes the problem to be solved at present.
The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art that is already known to a person skilled in the art.
Disclosure of Invention
The invention aims to provide a combined treatment process of aquatic product processing wastewater and domestic sewage, which can quickly recover protein in the aquatic product processing wastewater on the basis of the original domestic sewage treatment process, and simultaneously utilizes nutrient substances of excess sludge generated in the domestic sewage treatment process and the obtained protein to prepare animal feed with rich nutrition.
In order to achieve the above object, an embodiment of the present invention provides a combined treatment process for aquatic product processing wastewater and domestic sewage, comprising:
(1) The domestic sewage treatment process comprises the following steps: domestic sewage sequentially passes through a septic tank, a grating, a regulating tank, a hydrolysis acidification tank, an anaerobic tank, a contact oxidation tank, a sedimentation tank and a membrane bioreactor;
(2) Sludge acidification technology: conveying the sludge in the hydrolysis acidification tank to a sludge acidification tank, and performing hydrolysis acidification treatment in the sludge acidification tank, wherein the pH range is controlled to be 4.0-4.3;
(3) Pretreatment of aquatic product processing wastewater: treating the aquatic product processing wastewater by a grating and an oil removal tank;
(4) And (3) a mixed acidification process: conveying the aquatic product processing wastewater treated by the oil removal tank to a mixed acidification tank, conveying the mixed liquid in the sludge acidification tank to the mixed acidification tank for mixing, adjusting the pH value of the mixed liquid to 4.8-5.0, and continuing a hydrolysis acidification reaction;
(5) And (3) ultrafiltration process: when the pH value of the mixed solution in the mixed acidification tank is 4.5-4.6 after hydrolysis acidification reaction, the mixed solution in the mixed acidification tank is conveyed to an ultrafiltration tank for ultrafiltration treatment;
(6) The disinfection process comprises the following steps: conveying the concentrated water generated by the ultrafiltration process to a disinfection tank for disinfection treatment, and recovering protein in the concentrated water;
in one or more embodiments of the invention, the hydraulic retention time of the anaerobic tank is 15-24h;
in one or more embodiments of the invention, no acidic material is added to the pH control process in the sludge acidification tank;
in one or more embodiments of the invention, no acidic substance is added during the pH adjustment in the mixed acidification tank;
in one or more embodiments of the invention, a carbon source is added in the mixed acidification process, the carbon source is flour, and the carbon-nitrogen ratio in the mixed acidification process is controlled to be 3.1-3.5;
in one or more embodiments of the invention, the excess sludge produced by the sedimentation tank is dewatered and then transferred to the sludge acidification tank.
In one or more embodiments of the present invention, the dewatered excess sludge is subjected to a wall breaking treatment before being transferred to the sludge acidification tank.
In one or more embodiments of the invention, the protein obtained from the sterilization process is used in the preparation of animal feed.
In one or more embodiments of the invention, the settling tank utilizes dried sludge as a flocculant.
In one or more embodiments of the invention, the sludge acidification tank and the mixed acidification tank are arranged in the same reaction tank for acidification treatment.
In one or more embodiments of the invention, the fresh water produced by the ultrafiltration tank is delivered to the conditioning tank.
Compared with the prior art, the invention has the following advantages:
(1) The acidified sludge generated in the domestic sewage is used as a strain, the acidification is continued in a sludge acidification pool, and when the acidified sludge is mixed with the aquatic product processing wastewater after the oil removal treatment, the purposes of mixing the sludge with the wastewater and adsorbing protein and amino acid in the wastewater by the sludge are achieved;
(2) The mixture in the mixed acidification tank is acidified, so that the pH of the mixture is continuously reduced, the sedimentation performance of protein which is not adsorbed by microorganisms in the wastewater is improved, the filtration performance of ultrafiltration treatment is improved, and nutrient substances in the wastewater are recovered as much as possible;
(3) Excess sludge generated in the domestic sewage treatment process is reasonably utilized, nutrient substances removed from the excess sludge and additional flour are utilized as a carbon source, the recycling rate of protein is improved, and meanwhile, partial excess sludge is used as a raw material of animal feed;
(4) By utilizing the treatment process of domestic sewage in the prior art, the aquatic product processing wastewater can be treated by simple improvement, so that more than 85% of protein in the aquatic product processing wastewater can be recovered while the treatment cost of the aquatic product processing wastewater is reduced;
(5) The flour is used as the carbon source, so that the pH value is reduced, and the special flocculation effect of the flour can be utilized to perform the adsorption and flocculation effects on the protein, so that the recovery rate of the protein is improved.
Drawings
FIG. 1 is a schematic view of a process for the combined treatment of aquaculture wastewater and domestic sewage in accordance with an embodiment of the present invention;
FIG. 2 is a graphical representation of the relationship between pH of a mixed solution and protein recovery according to one embodiment of the present invention;
FIG. 3 is a graph illustrating pH and protein recovery of a mixed liquor after a mixed acidification process according to an embodiment of the present invention.
Detailed Description
The following detailed description of the present invention is provided in conjunction with the accompanying drawings, but it should be understood that the scope of the present invention is not limited to the specific embodiments.
Throughout the specification and claims, unless explicitly stated otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element or component but not the exclusion of any other element or component.
As shown in FIG. 1, the combined treatment process of aquaculture wastewater and domestic sewage according to the preferred embodiment of the invention comprises the following steps:
(1) The domestic sewage treatment process comprises the following steps: domestic sewage sequentially passes through a septic tank, a grid, a regulating tank, a hydrolysis acidification tank, an anaerobic tank, a contact oxidation tank, a sedimentation tank and a membrane bioreactor; the grating adopts a thick grating and a thin grating, the aperture of the thick grating is 10cm, and the aperture of the thin grating is 2cm; the retention time of the regulating pool is 4-5h; stirring in the hydrolysis acidification tank, wherein the stirrer is controlled at 50-70r/min; DO in the anaerobic tank is controlled to be 0.2mg/L, and the hydraulic retention time is 15-24h; the BOD volume load in the contact oxidation tank is controlled between 1.2 kg/m and 1.5kg/m 3 ·d；
(2) Sludge acidification technology: conveying the sludge in the hydrolysis acidification tank to a sludge acidification tank, and performing hydrolysis acidification treatment in the sludge acidification tank, wherein the pH range is controlled to be 4.0-4.3, and the hydraulic retention time is 2-4h;
(3) Pretreatment of aquatic product processing wastewater: treating the aquatic product processing wastewater in a grating oil removal tank, wherein the grating is a thick grating of 5cm and a thin grating of 1cm respectively; the oil removal pool adopts a horizontal flow type oil removal pool for treatment;
(4) And (3) a mixed acidification process: conveying the aquatic product processing wastewater treated by the oil removal tank to a mixed acidification tank, conveying the mixed liquor in the sludge acidification tank to the mixed acidification tank for mixing, adjusting the pH of the mixed liquor to 4.8-5.0, continuing a hydrolysis acidification reaction, adding a carbon source into the mixed acidification process, wherein the carbon source is flour, and controlling the carbon-nitrogen ratio in the mixed acidification process to be 3.1-3.5;
(5) And (3) ultrafiltration process: when the pH value of the mixed solution in the mixed acidification tank is 4.5-4.6 after hydrolysis acidification reaction, the mixed solution in the mixed acidification tank is conveyed to an ultrafiltration tank for ultrafiltration treatment;
(6) The disinfection process comprises the following steps: and conveying the concentrated water generated by the ultrafiltration process to a disinfection tank for disinfection treatment, and recovering protein in the concentrated water.
Wherein, the domestic sewage COD cr 1128mg/L and SS 621mg/L.
The initial protein content of the aquatic product processing wastewater is 10.5mg/L, the COD is 8143mg/L, and the pH value is 6.5-7.3.
The COD of the effluent after the treatment is reduced to 30-45mg/L, TN6-7mg/L and SS2-4mg/L.
Wherein, the pH of the sludge acidification process, the mixed acidification process and the ultrafiltration process has a significant influence on the protein recovery rate, wherein the relationship between the pH of the mixed solution entering the ultrafiltration tank and the protein recovery rate is shown in fig. 2; the relationship between the pH of the mixed solution after entering the mixed acidification process and the protein recovery (when the pH of the mixed solution in the ultrafiltration cell = 4.6) is shown in fig. 3.
The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and its practical application to enable one skilled in the art to make and use various exemplary embodiments of the invention and various alternatives and modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims and their equivalents.
Claims (7)
1. A combined treatment process for aquatic product processing wastewater and domestic sewage is characterized by comprising the following steps:
(1) The domestic sewage treatment process comprises the following steps: domestic sewage sequentially passes through a septic tank, a grating, a regulating tank, a hydrolysis acidification tank, an anaerobic tank, a contact oxidation tank, a sedimentation tank and a membrane bioreactor;
(2) Sludge acidification technology: conveying the sludge in the hydrolysis acidification tank to a sludge acidification tank, and performing hydrolysis acidification treatment in the sludge acidification tank, wherein the pH range is controlled to be 4.0-4.3;
(3) Pretreatment of aquatic product processing wastewater: treating the aquatic product processing wastewater by a grating and an oil removal tank;
(4) And (3) a mixed acidification process: conveying the aquatic product processing wastewater treated by the oil removal tank to a mixed acidification tank, conveying the mixed liquid in the sludge acidification tank to the mixed acidification tank for mixing, adjusting the pH of the mixed liquid to 4.8-5.0, continuing a hydrolysis acidification reaction, adding a carbon source in the mixed acidification process, wherein the carbon source is flour, controlling the carbon-nitrogen ratio in the mixed acidification process to be 3.1-3.5, adding no acidic substance in the pH control process in the sludge acidification tank, and adding no acidic substance in the pH adjustment process in the mixed acidification tank;
(5) And (3) ultrafiltration process: when the pH value of the mixed solution in the mixed acidification tank is 4.5-4.6 after hydrolytic acidification reaction, the mixed solution in the mixed acidification tank is conveyed to an ultrafiltration tank for ultrafiltration treatment;
(6) The disinfection process comprises the following steps: and conveying the concentrated water generated by the ultrafiltration process to a disinfection tank for disinfection treatment, and recovering the protein in the concentrated water.
2. The process of claim 1, wherein the hydraulic retention time of the anaerobic tank is 15-24h.
3. The process of claim 1, wherein the excess sludge from the sedimentation tank is dewatered and then transferred to the sludge acidification tank.
4. The process of claim 3, wherein the dewatered excess sludge is subjected to a wall breaking treatment before being delivered to the sludge acidification tank.
5. The process for the combined treatment of wastewater from aquatic processing and domestic sewage according to claim 1, wherein the protein obtained from said disinfection process is used in the preparation of animal feed.
6. The process of claim 1, wherein the sludge acidification tank and the mixed acidification tank are arranged in the same reaction tank for acidification treatment.
7. The process of claim 1, wherein the fresh water produced by the ultrafiltration tank is delivered to the conditioning tank.
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| JP4524522B2 (en) * | 2000-11-15 | 2010-08-18 | 栗田工業株式会社 | Treatment method for protein-containing wastewater |
| CN101624230B (en) * | 2008-07-11 | 2011-06-15 | 烟台海岸带可持续发展研究所 | Method of processing waste water and recycling protein |
| CN101700951A (en) * | 2009-11-20 | 2010-05-05 | 无锡市林信环保工程有限公司 | Emulsified liquid waste water treatment method |
| CN102250232A (en) * | 2011-06-29 | 2011-11-23 | 广东医学院 | Method for recovering protein from wastewater of shrimp processing enterprises |
| JP2013099731A (en) * | 2011-11-09 | 2013-05-23 | Sumitomo Heavy Ind Ltd | Method and apparatus for treatment of biological wastewater |
| CN103224309B (en) * | 2013-04-25 | 2014-06-25 | 西华大学 | Leather waste water treatment system and treatment process |
| CN105498700A (en) * | 2014-09-22 | 2016-04-20 | 北京大学深圳研究生院 | Bagasse mixing sludge adsorbent preparation and modification method |
| CN106490299A (en) * | 2016-10-20 | 2017-03-15 | 常州市鼎升环保科技有限公司 | A kind of method that recovery Sewage Plant second pond sludge prepares feed for shrimp and crab |
| CN107500476A (en) * | 2017-09-18 | 2017-12-22 | 河北德龙环境工程股份有限公司 | A kind of high protein waste water treatment process |
| CN107935314A (en) * | 2017-12-08 | 2018-04-20 | 广西永太和环保科技有限公司 | Soybean wastewater micro-organism treatment process |
| CN112625083B (en) * | 2020-12-16 | 2022-08-09 | 河北工业大学 | Method for efficiently recovering protein from excess sludge |
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