CN115028267A

CN115028267A - Waste water recycling device

Info

Publication number: CN115028267A
Application number: CN202210882522.3A
Authority: CN
Inventors: 贾方旭; 梅宁; 胡智丰; 姚宏
Original assignee: Beijing Jiaotong University
Current assignee: Beijing Jiaotong University
Priority date: 2022-07-26
Filing date: 2022-07-26
Publication date: 2022-09-09

Abstract

The application belongs to the technical field of waste water treatment, especially relates to a waste water recycling device. At present, food fermentation wastewater in China has huge amount, and the treatment process at present has high energy consumption and low energy recovery rate. The application provides a waste water recycling device, including grid well, sewage collecting pit, intake pump, anaerobism methanogenesis reactor, drying tube and the gas collection tank that connects gradually, anaerobism methanogenesis reactor, reducing reactor and product water tank connect gradually. Realizes deep denitrification and high-efficiency resource and reutilization of food fermentation wastewater.

Description

Waste water recycling device

Technical Field

The application belongs to the technical field of waste water treatment, and particularly relates to a waste water recycling device.

Background

According to the annual book data of Chinese environmental statistics, the total amount of COD discharged in the industrial wastewater in 2018 reaches 813894 tons, the discharge amount of ammonia nitrogen reaches 39863 tons, and the treatment amount of the industrial wastewater per day is 22370 ten thousand tons. The fermentation industry is a big drainage household in China, and the amount of waste water containing high-concentration ammonia nitrogen and COD discharged by the fermentation industry accounts for the 2 nd level of the light industry and is only second to the paper industry. The food processing industry is a main fermentation industry, the waste liquid remained in the production process belongs to high-concentration organic wastewater, the total COD (chemical oxygen demand) discharged by the food processing industry in 2018 reaches 155962 tons, and 8746 corresponding treatment facilities are provided in total.

As the fermentation wastewater has complex water quality and high pollutant concentration, and a single process link is difficult to meet the water quality standard requirement, a multi-technology combined process is often adopted, the current widely-applied treatment process is shown in figure 1 and comprises pretreatment, anaerobic treatment, aerobic treatment and advanced treatment links, the process is provided with complex and traditional aerobic biological sewage treatment processes which generally adopt blast aeration and mechanical aeration, wherein the former is to introduce air or pure oxygen into water by using an immersed porous diffuser or an air nozzle, and the latter is to dissolve air into water by using the stirring of mechanical equipment, and the bubbles generated by the two aeration modes are large, the rising speed in a water body is fast, the oxygen transfer efficiency is generally lower than 20%, the energy loss is large, and the operation cost is high.

Disclosure of Invention

1. Technical problem to be solved

Based on the problems that food fermentation wastewater in China is huge in quantity at present, and the energy consumption and the energy recovery rate of the treatment process are high at present, the application provides a wastewater recycling device.

2. Technical scheme

In order to reach foretell purpose, this application provides a waste water reuse device, including grid well, sewage collecting pit, intake pump, the anaerobism methanogenesis reactor, drying tube and the gas collection jar that connects gradually, anaerobism methanogenesis reactor, reducing reactor and product water tank connect gradually.

Another embodiment provided by the present application is: the solar water heater is characterized in that the water inlet pump, the electricity storage box and the solar panel are sequentially connected, the water inlet pump is connected with the control system, and the control system is connected with the electricity storage box.

Another embodiment provided by the present application is: the anaerobic methanogenesis reactor, the check valve, the reducing reactor connect gradually, check valve, backwash pump, fluidflowmeter with the reducing reactor connects gradually.

Another embodiment provided by the present application is: the reflux pump is connected with the control system, and the reflux pump, the air blower and the air flow meter are sequentially connected with the reducing reactor.

Another embodiment provided by the present application is: and an overflow pipe and an emptying pipe are arranged on the sewage collecting tank.

Another embodiment provided by the present application is: and a three-phase separator is arranged in the anaerobic methanogenesis reactor and is connected with the drying pipe.

Another embodiment provided by the present application is: an MABR membrane assembly is arranged in the reducing reactor and is connected with the air flow meter.

Another embodiment provided by the present application is: the hydraulic retention time of the anaerobic methanogenesis reactor is 8-12 hours.

Another embodiment provided by the present application is: the dissolved oxygen at the upper part of the MABR membrane component is 0.1-0.3 mg/L, and the dissolved oxygen at the lower part of the MABR membrane component is 0.

Another embodiment provided by the present application is: the drying tube is a U-shaped drying tube.

3. Advantageous effects

Compared with the prior art, the beneficial effect of the waste water recycling device that this application provided lies in:

the application provides a waste water recycling device, which is a high-efficiency coupled membrane aeration heterotrophic autotrophic nitrogen removal device for food fermentation waste water, and the quality of treated effluent water meets the discharge limit of pollutant discharge Standard of urban wastewater treatment plant (GB18918-2002) A.

The application provides a waste water recycling device adopts anaerobism methanogenesis reactor and reducing reactor to combine not only can retrieve most organic carbon in the sewage, adopts the MABR technology can save aeration rate moreover and reduce the working costs to can realize degree of depth denitrogenation through adjusting this system, realize the high-efficient resourceization and the reuse of food fermentation class waste water.

In the waste water recycling device provided by the application, the upper part of the reducing reactor is provided with the MABR membrane component, the lower part of the reducing reactor is provided with the granular sludge, the lower part of the reducing reactor is only provided with the granular sludge, the use of the MABR membrane component can be reduced, the construction cost of the treatment device is reduced, the sludge concentration in an MABR area can be reduced by partitioning the MABR and the granular sludge in the reactor, the formation of a cake layer on the surface of the MABR membrane component is reduced, the membrane pollution is reduced, in addition, COD can be utilized by denitrifying bacteria in the granular sludge after entering the granular sludge area of the reducing reactor, and the inhibition of COD on the inner layer of the granular sludge and the outer anaerobic ammonia oxidation bacteria of the upper MABR membrane component is avoided.

The application provides a waste water reuse device, through MABR foamless aeration, pass oxygen efficiently, power consumption is low, and is less to aquatic volatile substances influence, and the anaerobism methane production reactor most organic matter turns into methane in with sewage in addition, realizes the high-effect of sewage and gives birth to, and the play water after this system handles can be used for flushing toilet and afforestation, reduces the use to the running water. .

Drawings

FIG. 1 is a schematic view of a prior art fermentation-type wastewater treatment process of the present application;

fig. 2 is a schematic structural view of the wastewater reuse apparatus of the present application.

Detailed Description

Hereinafter, specific embodiments of the present application will be described in detail with reference to the accompanying drawings, and it will be apparent to those skilled in the art from this detailed description that the present application can be practiced. Features from different embodiments may be combined to yield new embodiments, or certain features may be substituted for certain embodiments to yield yet further preferred embodiments, without departing from the principles of the present application.

Referring to fig. 1-2, the application provides a waste water recycling device, including grid well 1, sewage collecting pit 2, intake pump 5, anaerobism methanogenesis reactor 7, drying tube 9 and the gas collection tank 10 that connect gradually, anaerobism methanogenesis reactor 7, reducing reactor 19 and product water tank 26 connect gradually. Adopt anaerobism methanogenesis reactor 7 and reducing reactor 19 to combine not only can retrieve most organic carbon in the sewage, adopt the MABR technology moreover can save aeration rate and reduce the working costs to can realize degree of depth denitrogenation through adjusting this system, realize the resource recovery and the recycle of food fermentation class waste water.

Specifically, firstly, food fermentation wastewater enters a sewage collecting tank 2 after intercepting suspended matters in water through a grid well 1, and then enters the bottom of an anaerobic methanogenic reactor 7 (the anaerobic methanogenic reactor is a UASB reactor) through a water inlet pump 5 according to the required flow, organic matters in the sewage are converted into methane under the action of anaerobic methanogenic bacteria, the generated methane enters a drying pipe, and is collected 10 by a gas collecting tank after being dried, the recovery of the organic matters is realized, most of the organic matters in the water are removed (more than or equal to 90%), and the efficient energy regeneration of the organic matters in the sewage is realized. The sewage treated by the anaerobic methanogenic reactor flows to the bottom of the reducing reactor 19, the residual organic matters in the water are subjected to denitrification decarbonization under the action of the denitrification granular sludge at the bottom of the reducing reactor 19 under the anaerobic environment at the bottom of the reducing reactor 19, the nitrate nitrogen with the upper part flowing back to the bottom is removed, the residual organic matters in the water are subjected to denitrification decarbonization under the action of the denitrification granular sludge at the bottom of the reducing reactor 19, the nitrate nitrogen with the upper part flowing back to the bottom is removed, and integrated partial nitrosation/anaerobic ammonia oxidation (integrated PN/A) denitrification is performed at the upper part through an MABR membrane module. Therefore, the anaerobic methanogenesis reactor is combined with the denitrification coupling integral PN/A reducing reactor to realize carbon recovery and deep denitrification of the food fermentation wastewater, the treated wastewater can meet the first-class A standard in the discharge Standard of pollutants for municipal wastewater treatment plant (GB18918-2002), and the anaerobic methanogenesis reactor can be used for flushing toilets and greening and realizes the recovery and utilization of water and nutrient substances in the food fermentation wastewater.

Further, the water inlet pump 5, the electricity storage box 11 and the solar cell panel 12 are connected in sequence, the water inlet pump 5 is connected with the control system 16, and the control system 16 is connected with the electricity storage box 11.

Further, the anaerobic methanogenesis reactor 7, the check valve 14 and the reducing reactor 19 are sequentially connected, and the check valve 14, the reflux pump 17 and the liquid flowmeter 20 are sequentially connected with the reducing reactor 19.

The sewage treated by the anaerobic methanogenic reactor 7 flows to the bottom of an anaerobic variable-diameter reactor 19 through a first water outlet 13, nitrate nitrogen generated by integral PN/A at the upper part of the variable-diameter reactor 19 flows back to the bottom of the variable-diameter reactor 19 through a reflux pump 17, a liquid flowmeter 20 is adjusted according to the removal condition of the nitrate nitrogen, the reflux flow rate is controlled, residual COD in the sewage is used as an organic carbon source by denitrifying bacteria in the area, the nitrate nitrogen is reduced into nitrogen through denitrifying action, the removal rate of the nitrate nitrogen in the area is over 85 percent, and the removal rate of the COD is over 90 percent under the synergistic action of the denitrifying bacteria and other anaerobic heterotrophic bacteria, so that deep carbon removal and nitrogen removal are realized at the bottom of the variable-diameter reactor 19.

The check valve 14 is used to prevent the water in the variable diameter reactor 19 from flowing back to the anaerobic methanogenic reactor 7.

Further, the reflux pump 17 is connected with the control system 16, and the reflux pump 17, the blower 18 and the air flow meter 21 are sequentially connected with the variable diameter reactor 19.

The reflux pump 17, the water pump, the aeration facility and the like are automatically controlled.

Furthermore, an overflow pipe 3 and a vent pipe 4 are arranged on the sewage collecting tank 2.

Further, a three-phase separator 8 is arranged in the anaerobic methanogenesis reactor 7, and the three-phase separator 8 is connected with the drying pipe. The drying tube is a U-shaped drying tube 9.

Methane enters a U-shaped drying pipe 9 under the action of a three-phase separator 8 in an anaerobic methanogenic reactor 7.

Further, an MABR membrane module 23 is arranged in the reducing reactor 19, and the MABR membrane module 23 is connected with the air flow meter 21.

The micro-aerobic environment is realized at the upper part of the reducing reactor 19 through bubble-free aeration of the MABR membrane module 23, denitrification is realized in the area through nitrosation/anaerobic ammonia oxidation of the integrated part, a small amount of generated nitrate nitrogen flows back to the bottom of the reactor through the reflux pump 17, the denitrification effect is performed for deep denitrification, and the sewage treated by the reducing reactor 19 flows to the water production tank 26 through the water outlet 2 for toilet flushing and greening.

The MABR membrane module 23 directly supplies oxygen to the microorganisms attached thereto by using a hollow fiber membrane, and has the following advantages in aeration: when in aeration and oxygen supply, no bubble is generated, the biological membrane can not fall off due to friction, and the oxygen permeates through the membrane fiber and is directly utilized by the biological membrane, thereby greatly reducing the mass transfer resistance of the oxygen and being beneficial to improving the oxygen supply speed and the oxygen utilization rate; oxygen and a substrate are subjected to mass transfer in a different direction, and the biological membrane can be obviously layered by controlling the aeration intensity, so that the effects of simultaneously nitrifying and denitrifying anaerobic ammonia oxidation and removing organic matters are achieved.

Adjusting the air flow of an MABR on the upper part of the reducing reactor 19 to control the upper Dissolved Oxygen (DO) at 0.1-0.3 mg/L and the lower DO at 0, realizing denitrification on the upper part of the reducing reactor 19 through integrated partial nitrosation/anaerobic ammoxidation, returning a small amount of generated nitrate nitrogen to the lower part of the reactor through a reflux pump 17, deeply denitrifying through denitrification, and allowing the water body treated by the reducing reactor 19 to flow to a water production tank 26 through a water outlet 2 for flushing and greening, thereby realizing the resource utilization of the food fermentation wastewater.

Furthermore, the food fermentation wastewater enters a sewage collecting tank after being intercepted by the grid well 1 to remove suspended matters in the water, and then the flow of a water inlet pump is controlled according to the Hydraulic Retention Time (HRT) of the anaerobic methanogenesis reactor 7, wherein the hydraulic retention time of the anaerobic methanogenesis reactor 7 is 8-12 hours. The HRT of the anaerobic methanogenic reactor 7 is adjusted according to the organic matter removal condition, and the organic matter removal rate can be improved by improving the HRT when the organic matter removal rate is low.

Furthermore, the dissolved oxygen at the upper part of the MABR membrane module 23 is 0.1-0.3 mg/L, and the dissolved oxygen at the lower part of the MABR membrane module 23 is 0.

Examples

A high-efficiency coupled membrane aeration heterotrophic autotrophic nitrogen removal device for food fermentation wastewater comprises the following steps that firstly, the food fermentation wastewater enters a sewage collection tank 2 through a grid well 1; the sewage collecting tank 2 is connected with an anaerobic methanogenesis reactor 7; a three-phase separator 8 of the anaerobic methanogenesis reactor 7 is connected with a U-shaped drying pipe 9; the rear part of the U-shaped drying pipe 9 is connected with a gas collecting tank 10 for collecting the generated methane; the anaerobic methanogenesis reactor 7 is connected with a check valve 14 through a water outlet 13; the back of the check valve 14 is connected with a denitrification coupling integral PN/A reducing reactor 19; the upper part of the reducing reactor 19 is connected with the lower part through a reflux pump 17; the rear part of the reducing reactor 19 is connected with a water production tank 26.

The back connection realize the connection for pipeline, valve, flowmeter and water pump through the difference, pipeline connection valve, flowmeter and water pump, valve, flowmeter and water pump pass through the pipeline and connect grid well 1, sewage collecting pit 2, anaerobism methanogenesis reactor 7, reducing reactor 19 and produce water tank 26 respectively.

The main water quality characteristics of the food fermentation wastewater are shown in the table 1-1:

TABLE 1.1 main Water quality characteristics of food fermentation wastewater

The grid well 1 intercepts suspended matters in the food fermentation wastewater; the sewage collecting tank 2 stores the food fermentation wastewater after suspended matters are intercepted by the grid well so as to provide sufficient water for the treatment device; sewage in the sewage collecting tank 2 enters an anaerobic methanogenesis reactor 7 through a water inlet pump 5, most organic matters in inlet water are converted into methane under the action of anaerobic methanogenesis bacteria, so that most organic matters (more than or equal to 90%) in the water are effectively removed, and simultaneously, the generated methane is collected after passing through a U-shaped drying pipe 9, so that carbon recovery of the food fermentation wastewater is realized; the food fermentation wastewater treated by the anaerobic methanogenic reactor 7 flows to the bottom of the reducing reactor 19 through the water outlet 1, and organic matters remained in the water under the anaerobic environment at the bottom of the reducing reactor 19 are subjected to denitrification decarbonization under the action of denitrification granular sludge, and nitrate nitrogen with the upper part returning to the bottom is removed; the micro-aerobic environment is realized at the upper part of the reducing reactor 19 through bubble-free aeration of an MABR membrane module 23, denitrification is realized in the area through integrated partial nitrosation/anaerobic ammonia oxidation, a small amount of generated nitrate nitrogen flows back to the bottom of the reactor through a reflux pump 17, and deep denitrification is performed; the effluent water after carbon recovery and denitrification through the anaerobic methanogenesis reactor 7 and the reducing reactor 19 is stored in a water production tank for flushing toilets and greening.

The aeration is carried out by adopting an MABR membrane component 23 which has high oxygen transfer efficiency and can reduce the electric quantity consumed when the aeration quantity is increased, and the membrane component carries out bubble-free aeration, can reduce the volatilization of volatile gas in food fermentation wastewater and reduce the adverse effect on the outside, an anaerobic methanogenesis reactor 7 is adopted to convert most organic matters in water into methane so as to recover the energy contained in organic carbon in sewage and reduce the inhibiting effect of the organic matters in water on subsequent functional microorganisms, the diameter-variable design is carried out on a diameter-variable reactor 19, the bottom of the reactor is favorable for sludge granulation due to larger height-diameter ratio, the inner diameter of the upper part of the reactor is favorable for placing more membrane wires to improve the treatment effect, the MABR is arranged on the upper part of the diameter-variable reactor 19 so as to realize DO partition, a micro-oxygen environment can be formed on the upper part of the reactor, and an anaerobic environment is formed on the lower part of the reactor, and then different microorganisms can form dominant microorganisms in the upper and lower regions of the reducing reactor 19, deep denitrification and carbon removal are realized in the reducing reactor 19, the treated water can be used for flushing toilets and greening, the use of tap water is reduced, and the recycling of food fermentation wastewater is realized.

Although the present application has been described above with reference to specific embodiments, those skilled in the art will recognize that many changes may be made in the configuration and details of the present application within the principles and scope of the present application. The scope of protection of the present application is determined by the appended claims, and all changes that come within the meaning and range of equivalency of the technical features of the claims are intended to be embraced therein.

Claims

1. A waste water recycling device is characterized in that: including grid well, sewage collecting pit, intake pump, anaerobism methanogenesis reactor, drying tube and the gas collecting tank that connects gradually, anaerobism methanogenesis reactor, reducing reactor and product water tank connect gradually.

2. The wastewater reuse apparatus according to claim 1, characterized in that: the solar water heater is characterized in that the water inlet pump, the electricity storage box and the solar panel are sequentially connected, the water inlet pump is connected with the control system, and the control system is connected with the electricity storage box.

3. The wastewater reuse apparatus according to claim 2, characterized in that: the anaerobic methanogenesis reactor, the check valve, the reducing reactor connect gradually, check valve, backwash pump, fluidflowmeter with the reducing reactor connects gradually.

4. The wastewater reuse apparatus according to claim 3, characterized in that: the reflux pump is connected with the control system, and the reflux pump, the air blower and the air flow meter are sequentially connected with the reducing reactor.

5. The wastewater reuse apparatus according to claim 1, characterized in that: and an overflow pipe and an emptying pipe are arranged on the sewage collecting tank.

6. The wastewater reuse apparatus according to claim 1, characterized in that: and a three-phase separator is arranged in the anaerobic methanogenesis reactor and is connected with the drying pipe.

7. The wastewater reuse apparatus according to claim 4, characterized in that: an MABR membrane assembly is arranged in the reducing reactor and is connected with the air flow meter.

8. The wastewater reuse apparatus according to claim 1, characterized in that: the hydraulic retention time of the anaerobic methanogenesis reactor is 8-12 hours.

9. The wastewater reuse apparatus according to claim 7, characterized in that: the dissolved oxygen at the upper part of the MABR membrane component is 0.1-0.3 mg/L, and the dissolved oxygen at the lower part of the MABR membrane component is 0.

10. The wastewater reuse apparatus according to any one of claims 1 to 9, characterized in that: the drying tube is a U-shaped drying tube.