CN111423033A - Wastewater treatment system and method - Google Patents

Wastewater treatment system and method Download PDF

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Publication number
CN111423033A
CN111423033A CN202010254621.8A CN202010254621A CN111423033A CN 111423033 A CN111423033 A CN 111423033A CN 202010254621 A CN202010254621 A CN 202010254621A CN 111423033 A CN111423033 A CN 111423033A
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CN
China
Prior art keywords
water
tank
wastewater
denitrification
nitrification
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202010254621.8A
Other languages
Chinese (zh)
Inventor
廖德祥
琚佳琪
冯道伦
王声东
吴长淋
胡超
魏福强
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai Environmental Sanitation Engineering Design Institute Co ltd
Shanghai Maritime University
Original Assignee
Shanghai Environmental Sanitation Engineering Design Institute Co ltd
Shanghai Maritime University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shanghai Environmental Sanitation Engineering Design Institute Co ltd, Shanghai Maritime University filed Critical Shanghai Environmental Sanitation Engineering Design Institute Co ltd
Priority to CN202010254621.8A priority Critical patent/CN111423033A/en
Publication of CN111423033A publication Critical patent/CN111423033A/en
Pending legal-status Critical Current

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    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F9/00Multistage treatment of water, waste water, or sewage
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F1/44Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
    • C02F1/444Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by ultrafiltration or microfiltration
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F1/46Treatment of water, waste water, or sewage by electrochemical methods
    • C02F1/469Treatment of water, waste water, or sewage by electrochemical methods by electrochemical separation, e.g. by electro-osmosis, electrodialysis, electrophoresis
    • C02F1/4691Capacitive deionisation
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F2001/007Processes including a sedimentation step
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00Nature of the contaminant
    • C02F2101/10Inorganic compounds
    • C02F2101/16Nitrogen compounds, e.g. ammonia
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00Biological treatment of water, waste water, or sewage
    • C02F3/30Aerobic and anaerobic processes
    • C02F3/302Nitrification and denitrification treatment

Abstract

The invention discloses a wastewater treatment system and a method, comprising the following steps: the raw water tank is used for containing wastewater to be treated; one end of the first power device is connected with the raw water pool; the ultrafiltration equipment, its one end links to each other with first power device's the other end for filter the waste water in the former pond: the concentrated water tank is used for containing tap water; one end of the fresh water tank is connected with the outlet end of the ultrafiltration device; the EDI equipment, wherein the water inlet and the water outlet of the fresh water chamber are respectively connected with the fresh water pool; wherein the water inlet and the water outlet of the concentration chamber are respectively connected with a concentration water pool; and the nitrification and denitrification device is connected with the water outlet end of the fresh water tank. By applying the embodiment of the invention, the problems of high energy consumption, high difficulty in culturing nitrobacteria and need of an additional carbon source in the prior art are solved.

Description

Wastewater treatment system and method
Technical Field
The invention relates to the technical field of wastewater treatment, in particular to a wastewater treatment system and a wastewater treatment method.
Background
At present, the traditional biological denitrification process is mostly adopted for treating the wastewater with high ammonia nitrogen and low carbon nitrogen ratio, most organic matters are degraded in a nitrification tank under the action of high-activity aerobic microorganisms, ammonia nitrogen and organic nitrogen are oxidized into nitrate and nitrite, the nitrate and nitrite flow back to a denitrification tank, and the nitrate and the nitrite are reduced into nitrogen in an anoxic environment to be discharged, so that the aim of denitrification is fulfilled. The nitrification, denitrification and deamination are the most widely applied denitrification technology at present, but the method has 3 defects in treating the high ammonia nitrogen wastewater: firstly, the nitrification requires high oxygen energy consumption; secondly, the nitrifying bacteria flora has low propagation speed and weak impact resistance, and the activity of microorganisms can be inhibited due to high ammonia nitrogen concentration, so that the system is difficult to stably operate; thirdly, carbon source is needed to be added in the denitrification, and the treatment cost is high.
Chinese patent documents: CN 105923774B (application number: 201610540191.X) discloses an invention patent named as 'a device and a method for realizing deep denitrification of sludge digestive juice by a three-stage type short-cut nitrification-anaerobic ammonia oxidation-short-cut denitrification process'. The method specifically comprises the following steps: the sludge digestive juice enters a short-cut nitrification reactor, the nitrite remained in the last period is removed by stirring the organic matters in the digestive juice under the anoxic condition, and then aeration is carried out for short-cut nitrification; and mixing the nitrite-containing effluent with the other part of sludge digestive liquid, then feeding the mixture into an anaerobic ammonia oxidation reactor for denitrification, feeding the effluent into a short-range denitrification reactor, converting nitrate generated in the anaerobic ammonia oxidation reaction process into nitrite, and refluxing the nitrite into the anaerobic ammonia oxidation reactor to further remove ammonia nitrogen in raw water. The method reduces the excess nitrate in the effluent of the anaerobic ammonia oxidation reactor into the substrate nitrite required by the anaerobic ammonia oxidation reaction, reduces the oxygen consumption in the aerobic process, has low carbon source consumption and low sludge yield, but still needs an additional carbon source when treating the wastewater with high ammonia nitrogen and low carbon nitrogen ratio, inhibits the activity of nitrobacteria in the high-concentration ammonia nitrogen wastewater, and has limited degree of reducing the oxygen consumption and certain defects.
Disclosure of Invention
The invention aims to provide a wastewater treatment system and a wastewater treatment method, and aims to solve the problems that the traditional biological denitrification process is high in oxygen energy consumption, high in nitrobacteria culture difficulty and needs an additional carbon source.
In order to achieve the above object, the present invention provides a wastewater treatment system comprising:
the raw water tank is used for containing wastewater to be treated;
one end of the first power device is connected with the raw water pool;
and one end of the ultrafiltration equipment is connected with the other end of the first power device and is used for filtering the wastewater in the raw water tank:
the concentrated water tank is used for containing experimental liquid;
one end of the fresh water tank is connected with the outlet end of the ultrafiltration device;
the EDI equipment, wherein the water inlet and the water outlet of the fresh water chamber are respectively connected with the fresh water pool; wherein the water inlet and the water outlet of the concentration chamber are respectively connected with the concentration water tank;
and the nitrification and denitrification device is connected with the water outlet end of the fresh water tank.
Preferably, the nitrification and denitrification device comprises:
the inlet end of the nitrification tank is connected with the water outlet end of the fresh water tank;
and the inlet end of the denitrification tank is connected with the outlet end of the nitrification tank.
Preferably, the method further comprises the following steps:
a water inlet end of the sedimentation tank is connected with an outlet end of the denitrification tank, wherein one outlet end of the sedimentation tank is connected with an inlet end of the nitrification tank;
and the water producing tank is connected with the other outlet end of the sedimentation tank.
Preferably, the method further comprises the following steps:
the second power device is arranged between a water inlet of the concentration chamber of the EDI equipment and the concentration water tank;
and the third power device is arranged between the fresh water chamber water inlet of the EDI equipment and the fresh water tank.
The invention also provides a wastewater treatment method, which is characterized by comprising the following steps:
pretreating the wastewater to remove macromolecular substances in the wastewater;
removing ammonia nitrogen from the pretreated wastewater through EDI equipment to reduce the concentration of ammonia nitrogen in the pretreated wastewater;
and (3) carrying out denitrification and decarbonization treatment on the wastewater subjected to the post-treatment of the EDI equipment by utilizing nitrification and denitrification processes.
The wastewater treatment system and method provided by the embodiment of the invention have the following beneficial effects:
(1) the method firstly reduces the ammonia nitrogen concentration in the wastewater, effectively reduces the oxygen consumed in the subsequent biological method treatment nitration process, and achieves the purposes of energy conservation and consumption reduction.
(2) The EDI equipment reduces the ammonia nitrogen concentration in the wastewater, can reduce the culture difficulty of nitrifying bacteria in the subsequent nitrification and denitrification process, and simplifies the process.
(3) The invention improves the carbon-nitrogen ratio in the wastewater to a reasonable ratio, so that an external carbon source is not needed in the denitrification stage, and the treatment cost is greatly reduced.
(4) The concentrated ammonia nitrogen in the concentrated water tank can be recycled.
Drawings
FIG. 1 is a schematic flow chart of an embodiment of the present invention.
Detailed Description
The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.
Please refer to fig. 1. It should be noted that the drawings provided in the present embodiment are only for illustrating the basic idea of the present invention, and the components related to the present invention are only shown in the drawings rather than drawn according to the number, shape and size of the components in actual implementation, and the type, quantity and proportion of the components in actual implementation may be changed freely, and the layout of the components may be more complicated.
The present invention provides a wastewater treatment system as shown in fig. 1, comprising: the raw water tank 1 is used for containing wastewater to be treated; a first power device 10, one end of which is connected with the raw water pool 1; and an ultrafiltration device 2, one end of which is connected with the other end of the first power device 10, and is used for filtering the wastewater in the raw water pool 1: the concentrated water tank 4 is used for containing experimental liquid, and specifically, the experimental liquid can be tap water or distilled water; one end of the fresh water tank 5 is connected with the outlet end of the ultrafiltration device 2; the EDI equipment 3, wherein the water inlet and the water outlet of the fresh water chamber are respectively connected with the fresh water pool 5; wherein the water inlet and the water outlet of the concentration chamber are respectively connected with the concentration water tank 4. Specifically, the water samples are processed in batches, the first stage is not connected with the second stage, and in the method, the batch of water samples enter EDI after the ultrafiltration is finished.
And the nitrification and denitrification device is connected with the water outlet end of the fresh water pool 5. The second power device 11 is arranged between the water inlet of the concentration chamber of the EDI equipment 3 and the concentrated water tank 4; the third power device 12 is arranged between the fresh water inlet of the EDI device 3 and the fresh water tank 5.
The EDI equipment comprises a homogeneous phase anion and cation exchange membrane, anion and cation exchange resin and electrode plates (anode plate and cathode plate). The EDI device is divided into a plurality of compartments by an ion exchange membrane, and comprises an anode compartment, a cathode compartment, a diluting compartment and a concentrating compartment. Mixing the resin in a ratio of 1: the 1 proportion fills the light chamber and plays a role in adsorbing and assisting ion migration. Specifically, the EDI device is an existing product, and the embodiment of the present invention is not described herein again.
It will be appreciated that the waste water is transported from the raw water basin 1 by the first power plant 10Sending the wastewater to an ultrafiltration device 2, pretreating the wastewater under the action of a tubular ultrafiltration technology to remove macromolecular substances such as suspended matters, colloids, bacteria and viruses in raw water, flowing the wastewater after ultrafiltration into a fresh water tank 5, refluxing the membrane concentrated solution after ultrafiltration into the raw water tank 1, and storing the wastewater in a concentrated water tank 4 (the liquid in the concentrated water tank may be full or not, for example, the volume of the wastewater can be set according to the volume of the wastewater, and the volume can be one half, one third or one fourth of the volume of the wastewater, and the like) at the same volume (different volumes, specifically, the volume can be set according to requirements) of experimental liquid (for example, tap water or distilled water) after the wastewater in the fresh water tank 5 is full. The water inlet and the water outlet of the fresh water chamber of the EDI equipment 3 are respectively communicated with the fresh water tank 5 through pipelines, the water inlet and the water outlet of the concentrated chamber are respectively communicated with the concentrated water tank 4 through pipelines, the third power device 12 and the second power device 11 are opened and the flow rate is controlled, so that water in the fresh water tank 5 and the concentrated water tank 4 respectively flows into the EDI equipment 3 from the water inlet at the bottom of the fresh water chamber and the water inlet at the bottom of the concentrated chamber, and NH in the wastewater4 +The ammonia nitrogen in the wastewater in the fresh water pool 5 can be effectively removed after the EDI equipment 3 operates for a period of time.
It should be noted that, as the third power device 12 and the second power device 11 are continuously transported, when the dilute chamber and the concentrated chamber of the EDI apparatus 3 are filled with water, the wastewater flows out from the water outlet at the top of the dilute chamber and flows back to the dilute water tank 5 along the pipeline, and the laboratory test liquid flows out from the water outlet at the top of the concentrated chamber and flows back to the concentrated water tank 4 along the pipeline. Under power device's effect, fresh water 5, 4 waters in the dense pond can constantly circulate and get into EDI equipment 3 and handle, until improving the carbon nitrogen ratio of waste water to reasonable proportion, wherein, be provided with the conductivity meter in fresh water 5, the dense pond 4, can monitor the waste water treatment effect, after waste water reaches the target treatment effect in fresh water 5, draw fresh water 5 normal water to the denitrification facility that nitrifies.
Preferably, the nitrification and denitrification device comprises:
the inlet end of the nitrification tank 6 is connected with the water outlet end of the fresh water tank 5;
and the inlet end of the denitrification tank 7 is connected with the outlet end of the nitrification tank 6.
It can be understood that the water in the fresh water pool is sampled in the treatment process, when the concentration of ammonia nitrogen in the wastewater reaches the ammonia nitrogen concentration range required by the nitrification and denitrification stage, the water in the fresh water pool 5 is led to the nitrification and denitrification treatment device, the ammonia nitrogen is oxidized into nitrate nitrogen and nitrite nitrogen in the anoxic environment of the nitrification pool 6 and under the action of nitrifying bacteria, and the nitrate nitrogen is reduced into nitrogen in the aerobic environment of the denitrification pool 7 and is discharged. Because the ammonia nitrogen concentration is reduced, the oxygen energy consumption in the nitrification process is reduced, the activity of nitrifying bacteria is not inhibited, the difficulty of the culture technology is reduced, the carbon-nitrogen ratio in the wastewater is reasonable, no additional carbon source is needed in the denitrification process, the water body flowing back to the nitrification tank 6 is greatly reduced, and the volume of the nitrification tank 6 can be reduced, wherein the aeration device is installed in the nitrification tank 6, and the stirring device is installed in the denitrification tank 7.
In one implementation, the method further comprises:
a sedimentation tank 8, the water inlet end of which is connected with the outlet end of the denitrification tank 7, wherein one outlet end is connected with the inlet end of the nitrification tank 6,
and the water producing tank 9 is connected with the other outlet end of the sedimentation tank 8.
The wastewater treated by the nitrification and denitrification device flows into the sedimentation tank 8 for sludge-water separation, the produced water flows into the water production tank 9, and the sludge flows back into the nitrification tank 6.
The invention also provides a wastewater treatment method, which comprises the following steps:
pretreating the wastewater to remove macromolecular substances in the wastewater;
removing ammonia nitrogen from the pretreated wastewater through EDI equipment to reduce the concentration of ammonia nitrogen in the pretreated wastewater;
and (3) carrying out denitrification and decarbonization treatment on the wastewater subjected to the post-treatment of the EDI equipment by utilizing nitrification and denitrification processes.
The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.

Claims (5)

1. A wastewater treatment system, comprising:
the raw water pool (1) is used for containing wastewater to be treated;
a first power device (10), one end of which is connected with the raw water pool (1);
and one end of the ultrafiltration equipment (2) is connected with the other end of the first power device (10) and is used for filtering the wastewater in the raw water pool (1):
the concentrated water tank (4) is used for containing experimental liquid;
one end of the fresh water tank (5) is connected with the outlet end of the ultrafiltration device (2);
the EDI equipment (3), wherein the water inlet and the water outlet of the fresh water chamber are respectively connected with the fresh water pool (5); wherein the water inlet and the water outlet of the concentration chamber are respectively connected with the concentrated water tank (4);
and the nitrification and denitrification device is connected with the water outlet end of the fresh water tank (5).
2. The wastewater treatment system of claim 1, wherein the nitrification denitrification apparatus comprises:
the inlet end of the nitrification tank (6) is connected with the water outlet end of the fresh water tank (5);
and the inlet end of the denitrification tank (7) is connected with the outlet end of the nitrification tank (6).
3. The wastewater treatment system of claim 2, further comprising:
a sedimentation tank (8), the water inlet end of which is connected with the outlet end of the denitrification tank (7), wherein one outlet end is connected with the inlet end of the nitrification tank (6);
and the water producing tank (9) is connected with the other outlet end of the sedimentation tank (8).
4. The wastewater treatment system of claim 3, further comprising:
the second power device (11) is arranged between a water inlet of the concentrate chamber of the EDI equipment (3) and the concentrate tank (4);
the third power device (12) is arranged between the fresh water inlet of the EDI equipment (3) and the fresh water tank (5).
5. A method of wastewater treatment, the method comprising:
pretreating the wastewater to remove macromolecular substances in the wastewater;
removing ammonia nitrogen from the pretreated wastewater through EDI equipment to reduce the concentration of ammonia nitrogen in the pretreated wastewater;
and (3) carrying out denitrification and decarbonization treatment on the wastewater subjected to the post-treatment of the EDI equipment by utilizing nitrification and denitrification processes.
CN202010254621.8A 2020-04-02 2020-04-02 Wastewater treatment system and method Pending CN111423033A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010254621.8A CN111423033A (en) 2020-04-02 2020-04-02 Wastewater treatment system and method

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Application Number Priority Date Filing Date Title
CN202010254621.8A CN111423033A (en) 2020-04-02 2020-04-02 Wastewater treatment system and method

Publications (1)

Publication Number Publication Date
CN111423033A true CN111423033A (en) 2020-07-17

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CN202010254621.8A Pending CN111423033A (en) 2020-04-02 2020-04-02 Wastewater treatment system and method

Country Status (1)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013074929A1 (en) * 2011-11-16 2013-05-23 Siemens Industry, Inc. Using continuous nitrate measurement to control aeration in an aerated-anoxic process
NL1041567A (en) * 2015-11-12 2017-05-29 Kamplan B V Method for treating manure.
CN107840537A (en) * 2017-11-10 2018-03-27 深圳能源资源综合开发有限公司 Method for treating garbage percolation liquid and system
CN207483528U (en) * 2017-11-10 2018-06-12 深圳能源资源综合开发有限公司 Garbage percolation liquid treating system
CN108164084A (en) * 2017-12-21 2018-06-15 同济大学 A kind of nitrogenous organic wastewater treating system and its method

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013074929A1 (en) * 2011-11-16 2013-05-23 Siemens Industry, Inc. Using continuous nitrate measurement to control aeration in an aerated-anoxic process
NL1041567A (en) * 2015-11-12 2017-05-29 Kamplan B V Method for treating manure.
CN107840537A (en) * 2017-11-10 2018-03-27 深圳能源资源综合开发有限公司 Method for treating garbage percolation liquid and system
CN207483528U (en) * 2017-11-10 2018-06-12 深圳能源资源综合开发有限公司 Garbage percolation liquid treating system
CN108164084A (en) * 2017-12-21 2018-06-15 同济大学 A kind of nitrogenous organic wastewater treating system and its method

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
武占: "《油田注汽锅炉》", 31 August 2008, 上海交通大学出版社 *

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