Short-process sewage treatment equipment and method based on MABR process

Abstract

The application discloses a kind of short process sewage treatment equipment and processing method based on MABR process, including water distribution system, MABR reaction zone, MABR membrane assembly, gas supply and flushing system, clear water area, backwashing automatic control system, water production system and liquid level control system.The application short process, simple operation, compared with other sewage treatment systems, the application reduces anaerobic zone, anoxic zone and aerobic zone, reflux system and other complex processes and control, only using MABR one kind of treatment process realizes the discharge of sewage up to standard, using MABR bubbleless aeration technology, aeration efficiency is 4-5 times of conventional aerator, and there is no nitrification liquid reflux pump, sludge reflux pump and agitator, greatly reduce equipment investment and energy consumption, the application adopts vertical tank body structure design, compared with other integrated equipment, greatly save floor area.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of water treatment, and relates to a sewage treatment device and method, in particular to a short-process sewage treatment device and method based on a MABR process, which can ensure water quality and has obvious energy-saving effect. BACKGROUND

[0002] The membrane aerated biofilm reactor (MABR) is a treatment process for realizing degradation of pollutants in sewage by using a biofilm system attached and grown on the surface of a carrier through an oxygen permeable membrane as the carrier. The MABR realizes bubbleless aeration and molecular oxygen transmission by virtue of its special material properties, and greatly improves the oxygen transmission efficiency compared with other aeration systems. However, in the actual operation process, the gas supplied by the MABR membrane system is directly discharged into the atmosphere or further utilized for gas stirring of sewage after oxygen transmission. For multiple MABR systems, the amount of gas is large, and there is still a large amount of oxygen in the gas after oxygen transmission which is not utilized, and the direct discharge causes great resource waste. In addition, the gas stirring of sewage requires an increase in the supply pressure, and the utilization rate of the gas is very low, which is a process of increasing energy consumption. In order to further save energy and increase the oxygen transmission efficiency of the MABR, a new MABR operation process is needed.

[0003] The conventional integrated sewage treatment process needs to design anaerobic, anoxic and aerobic processes to realize the effects of denitrification, phosphorus removal and COD removal, which results in a long process, large occupation and many devices of the treatment equipment, and also leads to complex control. In addition, the conventional aerobic process often needs to be realized by aeration, and the aeration process releases the original or generated wastewater in the treatment process into the atmosphere, thereby causing air pollution.

[0004] For the MABR sewage treatment process, a matching filtration and sedimentation system also needs to be designed. The conventional secondary sedimentation tank often has the problem of mud running, which results in unqualified effluent. In addition, there are problems of poor impact resistance and poor sanitary conditions. The use of filtration equipment will result in an increase in equipment investment, an increase in the occupation area and complex control.

[0005] Therefore, a short-process, easy-to-control, stable, small-occupation-area, reliable and safe device and operation process has great significance. SUMMARY

[0006] The problems to be solved by the present application include: 1. the problems of long process, more configuration and complex control of the current integrated device; 2. the problem of poor sedimentation effect and poor effluent quality of the conventional sedimentation tank; 3. the problem of high energy consumption of the conventional sewage treatment device; and 4. the problem of air pollution caused by odor or volatile gas of the conventional sewage treatment process.

[0007] In order to solve the above problems, the first aspect of the present application provides a short process sewage treatment equipment based on MABR process, the short process sewage treatment equipment of the present application has good effluent water quality, simple process, less equipment configuration, obvious energy saving effect, environmental protection safety and land saving.

[0008] The second aspect of the present application provides a short process sewage treatment method based on MABR process, the treatment method of the present application has short process, simple operation, obvious energy saving effect and good effluent water quality.

[0009] In order to achieve the above-mentioned purpose, the present application adopts the following technical scheme:

[0010] Firstly, the present application provides a short process sewage treatment equipment based on MABR process, the short process sewage treatment equipment comprises a water distribution system, a MABR reaction zone, a MABR membrane assembly, a gas supply and flushing system, a clear water zone, an automatic backwashing control system, a water production system and a liquid level control system.

[0011] The MABR reaction zone comprises a high-load MABR reaction zone and a low-load MABR reaction zone, the MABR membrane wire of the MABR membrane assembly is placed in parallel with the water flow direction in the high-load MABR reaction zone, the MABR membrane wire of the MABR membrane assembly is placed vertically to the water flow direction in the low-load MABR reaction zone, and the MABR membrane assembly is a curtain type membrane assembly in which the MABR membrane wire is woven into a net shape.

[0012] The MABR membrane assembly cleaning of the low-load MABR reaction zone comprises the automatic backwashing control system and the gas supply and flushing system.

[0013] In the present application, the MABR membrane assembly is placed in parallel with the water flow direction in the high-load MABR reaction zone, which mainly functions to ensure the sufficient contact between the pollutants in the influent and the MABR membrane assembly, and to reduce the head loss (or resistance loss) in the operation process, thereby ensuring the stable operation of the system.

[0014] The MABR membrane assembly is placed vertically to the water flow direction in the low-load MABR reaction zone, which mainly functions to further react the remaining pollutants in the area after the removal effect of the high-load MABR reaction zone, and the vertical placement not only ensures the sufficient contact between the pollutants and the MABR membrane, but also more importantly traps the sludge, thereby ensuring the effluent effect.

[0015] As a preferred scheme of the present application, the short process sewage treatment equipment is in a cylindrical structure, and sequentially comprises a sedimentation zone, a water distribution zone, a high-load MABR zone, an automatic backwashing control system, a low-load MABR zone, a clear water zone from bottom to top, and the height of the short process sewage treatment equipment is greater than 4m; and the water production system is arranged in the clear water zone.

[0016] As a preferred scheme of the present application, the spacing between the woven MABR hollow fiber membrane filaments in the MABR membrane assembly is 0.3-0.6 mm.

[0017] In the present application, the smaller the spacing, the higher the filtration precision and the better the water quality; the smaller the spacing, the faster the MABR membrane biofilm formation and the shorter the biological cultivation time. Too small spacing also has the problem of high filtration resistance, increasing the operating energy consumption. Therefore, the present application sets the spacing between the woven MABR hollow fiber membrane filaments to be 0.3-0.6 mm.

[0018] As a preferred scheme of the present application, the gas supply and flushing system simultaneously supplies gas to the high-load MABR zone membrane assembly and the low-load MABR zone membrane assembly.

[0019] As a preferred scheme of the present application, the gas supply and flushing system flushes the MABR membrane assembly every certain period of time (1-3 min).

[0020] As a preferred scheme of the present application, the water inlet of the backwashing automatic control system is arranged at a position between the low-load MABR zone and the high-load MABR zone, and the low-load MABR zone membrane assembly is backwashed every certain period of time (30-120 min).

[0021] As a preferred scheme of the present application, the clean water zone is arranged at the upper part of the low-load MABR zone.

[0022] As a preferred scheme of the present application, the liquid level control system comprises a pump stopping limit gauge and a pump starting limit gauge, the pump stopping limit gauge is located in the clean water zone, and the pump starting limit gauge is flush with the water inlet of the backwashing automatic control system.

[0023] As a preferred scheme of the present application, it further comprises an adjusting tank and a sludge discharge system, the upper part of the adjusting tank is connected with the backwashing automatic control system, the lower part of the adjusting tank is connected with the water distribution system, and the sludge discharge system is arranged below the sedimentation zone.

[0024] Secondly, the present application also provides a treatment method of the MABR membrane-based short-process sewage treatment equipment, comprising the following steps: S1: sewage enters the MABR membrane-based integrated sewage treatment device through the water distribution system for water quality uniform distribution, and then sequentially passes through the high-load MABR reaction zone and the low-load MABR reaction zone from bottom to top for pollutant degradation, at the same time, the SS and other pollutants in the sewage are intercepted by the MABR membrane assembly in the low-load MABR zone to complete sewage purification, and the purified water enters the clean water zone and is discharged after reaching the standard;

[0025] S2: When the MABR membrane assembly resistance of the low load MABR zone increases, the backwashing automatic control system is started, the sewage to be treated in the short-flow sewage treatment equipment is discharged to the adjusting tank by the backwashing automatic control system, and the liquid level of the clear water zone is lowered;

[0026] S3: The liquid level of the reaction tank clear water zone is lower than the pump stop limit gauge, the water inlet pump is closed, the clear water zone water flows reversely to backwash the MABR membrane wire of the MABR membrane assembly of the low load MABR zone, and the flushing aeration system at the lower part of the MABR membrane assembly is operated to flush the MABR membrane wire of the MABR membrane assembly of the low load MABR zone;

[0027] S4: When the liquid level in the reaction tank is lowered to the installation position of the backwashing automatic control system, the backwashing automatic control is destroyed, the backwashing is stopped, the water level in the treatment device is no longer lowered, and the liquid level reaches the pump starting limit point;

[0028] S5: The water inlet pump is started, and the sewage treatment process S1 is carried out.

[0029] S6: When the flushing process lasts for N cycles, the sludge in the sedimentation zone is discharged.

[0030] Compared with the prior art, the present application has the following beneficial effects:

[0031] 1) The present application has a short process and simple operation, compared with other sewage treatment systems, the present application reduces the complex process and control of the anaerobic zone, the anoxic zone, the aerobic zone and the reflux system, and only uses MABR to realize the standard discharge of sewage.

[0032] 2) The present application has good effluent water quality, compared with conventional sewage treatment systems, the sedimentation effect of the secondary sedimentation tank is poor, the impact resistance is not high, and the effluent water quality is poor, the present application uses precise MABR membrane as the filter medium to ensure the effluent water quality, and secondly, MABR has the functions of oxygen supply and biological membrane, which realizes the deep removal of pollutants and further ensures the treatment effect.

[0033] 3) The present application has obvious energy saving effect, compared with the traditional integrated equipment, the traditional integrated equipment usually uses aeration pipe or aeration disc for oxygen supply aeration, the aeration efficiency is low, and secondly, the system usually needs to be equipped with a stirrer, a nitrification liquid reflux pump, a sludge reflux pump and other equipment, which further increases the energy consumption per ton of water treatment, the present application uses MABR bubbleless aeration technology, the aeration efficiency is 4-5 times that of conventional aerators, and there is no nitrification liquid reflux pump, sludge reflux pump and stirrer, which greatly reduces the energy consumption investment.

[0034] 4) The present application is environmentally friendly and safe, MABR belongs to bubbleless aeration, and waste gas or other polluting substances will not be volatilized through the aeration process during the sewage treatment process, and the atmosphere will not be polluted.

[0035] 5) The application saves the land occupation, adopts the vertical tank body structure design, and greatly saves the land occupation area compared with other integrated equipment. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 is the schematic diagram of the application.

[0037] Figure 2 is the enlarged view of A of the application.

[0038] Figure 3 is the B-B sectional view of the application.

[0039] In the figure, 1. reaction tank; 2. precipitation area; 3. water distribution system; 3-1. water inlet pump; 3-2. pump stop limit meter; 3-3. pump start limit meter; 4. high load MABR area; 4-1. MABR membrane assembly; 4-2. gas supply system; 4-3. flushing system; 5. backwashing automatic control system; 6. low load MABR area; 7. clean water area; 8. water production system; 9. adjusting tank; 10. sludge discharge system. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the embodiments of the application. Obviously, the described embodiments are only a part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the application.

[0041] Referring to Figure 1 , the application provides a short process sewage treatment equipment based on MABR process, the short process sewage treatment equipment 1 includes a water distribution system 3, a MABR reaction area, a MABR membrane assembly 4-1, a gas supply and flushing system, a clean water area 7, a backwashing automatic control system 5, a water production system 8, a liquid level control system, an adjusting tank 9 and a sludge discharge system 10.

[0042] The MABR reaction area includes a high load MABR reaction area 4 and a low load MABR reaction area 6.

[0043] Referring to Figure 2 , the MABR membrane assembly 4-1 is placed in the direction parallel to the water flow direction in the high load MABR reaction area 4; referring to Figure 3 , the MABR membrane assembly 4-1 is placed in the direction vertical to the water flow direction in the low load MABR reaction area 6, and the structure of the MABR membrane assembly 4-1 is a curtain type membrane assembly woven by membrane filaments into a net shape.

[0044] The MABR membrane assembly cleaning of the low load MABR reaction area includes the backwashing automatic control system 5 and the gas supply and flushing system.

[0045] Water distribution system 3 is arranged below high load MABR reaction zone 4, including water distribution pipeline and water inlet pump 3-1.

[0046] As an alternative, the application can raise the position of the adjusting pool to realize gravity water inlet, and then the water inlet pump can not be used.

[0047] The air supply and flushing system includes an external air inlet pump, air supply system 4-2 and flushing system 4-3, air supply system 4-2 simultaneously supplies air to the membrane assembly of high load MABR zone 4 and the membrane assembly of low load MABR zone 6.

[0048] Flushing system 4-3 flushes the membrane assembly of high load MABR zone 4 every certain period of time (1-3 min).

[0049] Short process sewage treatment equipment 1 is a cylindrical structure, from bottom to top in turn is sedimentation zone 2, water distribution zone, high load MABR zone 4, backwashing automatic control system 5, low load MABR zone 6, clear water zone 7, and the height of short process sewage treatment equipment is greater than 4 m; water production system 8 is arranged in clear water zone 7.

[0050] The spacing between the woven MABR hollow fiber membrane filaments in the MABR membrane assembly is 0.3-0.6 mm. The smaller the spacing, the higher the filtration precision and the better the water quality; the smaller the spacing, the faster the MABR membrane film is formed, and the shorter the biological culture time. If the spacing is too small, there is also the problem of high filtration resistance, which increases the operating energy consumption. Therefore, the application sets the spacing between the woven MABR hollow fiber membrane filaments to 0.3-0.6 mm.

[0051] The water inlet of backwashing automatic control system 5 is arranged at the intermediate position between low load MABR zone 6 and high load MABR zone 4, and the membrane assembly of low load MABR zone is backwashed every certain period of time (30-120 min).

[0052] As an alternative, the application can also not use backwashing automatic control system, but use a back suction pump to clean the membrane assembly of low load MABR zone.

[0053] Clear water zone 7 is arranged at the upper part of low load MABR zone 6, with a distance of 20-30 cm.

[0054] The liquid level control system includes pump stop limit meter 3-2 and pump start limit meter 3-3, pump stop limit meter 3-2 is located in clear water zone, pump start limit meter 3-3 is at the same height as the water inlet of backwashing automatic control system 5, and the highest point of backwashing automatic control system 5 is higher than pump stop limit meter 3-2.

[0055] The upper part of the adjusting tank 9 is connected with the backwashing automatic control system 5, and the lower part of the adjusting tank 9 is connected with the water inlet pump 3-1; the sludge discharge system 10 is arranged below the sedimentation zone 2.

[0056] Embodiment 1

[0057] The embodiment provides a short-process sewage treatment method based on an MABR process, and comprises the following steps:

[0058] S1: sewage enters a treatment device and is uniformly distributed through a water distribution system, and then the sewage (or sludge-water mixture) sequentially passes through a high-load MABR reaction zone and a low-load MABR reaction zone from bottom to top for pollutant degradation; the high-load MABR zone mainly removes most of COD, NH4-N and TN, and then the sewage (or sludge-water mixture) further reaches the low-load MABR zone, the low-load MABR zone can further realize degradation of the pollutants, so that the COD, NH4-N and TN of the effluent meet the standards, meanwhile, the MABR membrane of the low-load MABR zone can also realize interception of SS to further ensure the water quality of the effluent, and finally, sewage purification is completed, and the purified water enters a clear water zone and is discharged after meeting the standards;

[0059] S2: as the sewage treatment proceeds, the MABR membrane of the low-load MABR zone intercepts more and more SS, the effluent resistance increases, the liquid level of the backwashing automatic control system continuously rises, when the liquid level reaches the highest point of the backwashing automatic control system, the backwashing automatic control system is started, and the sewage (sludge-water mixture) in the treatment device is discharged to the adjusting tank by the backwashing automatic control system, and the liquid level of the clear water zone is lowered;

[0060] S3: when the liquid level of the clear water zone of the reaction tank is lower than a pump stop limit gauge, the water inlet pump is closed, the water in the clear water zone flows reversely through the MABR membrane of the MABR membrane assembly of the low-load MABR zone, the MABR membrane of the MABR membrane assembly of the low-load MABR zone is backwashed, and the flushing aeration system at the lower part of the MABR membrane assembly operates to flush the MABR membrane of the MABR membrane assembly of the low-load MABR zone; the SS accumulated in the MABR membrane assembly of the low-load MABR zone is stripped and cleaned, and the stripped and cleaned SS (or active sludge in the system) is deposited in the sedimentation zone of the reaction tank under the action of gravity;

[0061] S4: when the liquid level in the reaction tank is lowered to the installation position of the water inlet of the backwashing automatic control, the water inlet of the backwashing automatic control enters air, the backwashing automatic control is destroyed, the backwashing is stopped, and the liquid level in the treatment device no longer decreases, and the liquid level reaches a pump starting limit point;

[0062] S5: the water inlet pump is started, and the sewage treatment process S1 is performed;

[0063] S6: When the flushing process lasts for N cycles, the sludge in the sedimentation zone is discharged.

[0064] The effluent water can meet the actual engineering needs. When the effluent water is required to be level A, the effluent water of the short-flow sewage treatment device has a COD of 30-40 mg / L, SS less than 10 mg / L, ammonia nitrogen of 0.3-1 mg / L, TN of 10-14 mg / L, and TP less than 0.5 mg / L.

[0065] The above description is only a preferred embodiment of the present application, and is not intended to limit the present application in any form or in essence. It should be noted that, for those skilled in the art, without departing from the method of the present application, some improvements and supplements can also be made, which should be considered as the protection scope of the present application. For those skilled in the art, without departing from the spirit and scope of the present application, some changes, modifications and equivalent changes can be made based on the disclosed technical content, which are equivalent embodiments of the present application. Meanwhile, any equivalent changes, modifications and evolution of the above-mentioned embodiments according to the essential technology of the present application are still within the scope of the technical solutions of the present application.

Claims

1. A short-process wastewater treatment device based on MABR technology, characterized in that, The aforementioned short-process wastewater treatment equipment includes a water distribution system, a MABR reaction zone, a MABR membrane module, an air supply and flushing system, a clear water zone, an automatic backwashing control system, a product water system, and a liquid level control system. The MABR reaction zone includes a high-load MABR reaction zone and a low-load MABR reaction zone. The MABR membrane fibers of the MABR membrane module are placed in the direction parallel to the water flow direction in the high-load MABR reaction zone, and in the direction perpendicular to the water flow direction in the low-load MABR reaction zone. The MABR membrane module structure is a curtain-type membrane module with membrane fibers woven into a mesh. The cleaning of the MABR membrane module in the low-load MABR reaction zone includes an automatic backwashing control system and an air supply and flushing system. The aforementioned short-process wastewater treatment equipment has a cylindrical structure, consisting of a sedimentation zone, a water distribution zone, a high-load MABR zone, a backwash automatic control system, a low-load MABR zone, and a clear water zone from bottom to top. The height of the short-process wastewater treatment equipment is greater than 4m. The water production system is located in the clear water zone.

2. The short-process wastewater treatment equipment based on MABR technology according to claim 1, characterized in that, The spacing between the woven MABR hollow fiber membrane filaments in the MABR membrane module is 0.3-0.6 mm.

3. The short-process wastewater treatment equipment based on MABR technology according to claim 1, characterized in that, The gas supply and flushing system described herein supplies gas to the MABR membrane module.

4. A short-process wastewater treatment device based on MABR technology according to claim 1, characterized in that, The gas supply and flushing system flushes the MABR membrane module at regular intervals.

5. A short-process wastewater treatment device based on MABR technology according to claim 1, characterized in that, The inlet of the backwashing automatic control system is located between the low-load MABR zone and the high-load MABR zone, and backwashes the membrane module in the low-load MABR zone at regular intervals.

6. A short-process wastewater treatment device based on MABR technology according to claim 1, characterized in that, The clear water zone is located above the low-load MABR zone.

7. A short-process wastewater treatment device based on MABR technology according to claim 1, characterized in that, The liquid level control system includes a pump stop limit gauge and a pump start limit gauge. The pump stop limit gauge is located in the clean water zone, and the pump start limit gauge is flush with the inlet of the backwash automatic control system.

8. A short-process wastewater treatment device based on MABR technology according to claim 1, characterized in that, It also includes an equalization tank and a sludge removal system. The upper part of the equalization tank is connected to the backwashing automatic control system, and the lower part of the equalization tank is connected to the water distribution system. The sludge removal system is located below the sedimentation zone.

9. A treatment method using the short-process wastewater treatment equipment according to any one of claims 1-8, characterized in that, The processing method includes the following steps: S1: Wastewater enters the integrated wastewater treatment device based on MABR process and is evenly distributed through the water distribution system. Then, from bottom to top, it passes through the high-load MABR reaction zone and the low-load MABR reaction zone to degrade pollutants. The MABR membrane module in the low-load MABR zone intercepts and completes the wastewater purification. The purified water enters the clear water zone and is discharged after meeting the standards. S2: When the resistance of the MABR membrane module in the low-load MABR zone increases, the backwashing automatic control system is activated, and the liquid to be treated in the short-process wastewater treatment equipment is discharged to the equalization tank by the backwashing automatic control system, and the liquid level in the clear water zone decreases. S3: When the liquid level in the clear water zone of the reaction tank is lower than the pump stop limit gauge, the inlet pump is shut off, and the water in the clear water zone flows in reverse to backwash the MABR membrane module in the low-load MABR zone. At the same time, the flushing and aeration system at the bottom of the MABR membrane module is running to flush the MABR membrane module in the low-load MABR zone. S4: When the liquid level in the reaction tank drops to the installation position of the inlet of the backwash automatic control, the backwash automatic control is disrupted, backwashing stops, the water level in the treatment device no longer drops, and the liquid level reaches the pump start limit point. S5: The inlet pump starts, and the sewage treatment process S1 begins; S6: After the flushing process continues for N cycles, the sludge in the sedimentation zone is discharged.

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