CN103183412A - Biochemical treatment device for sewage and treatment method thereof - Google Patents

Abstract

The invention relates to a sewage biochemical treatment device, comprising an air supply pipe, a biochemical pool body, a water outlet and a sewage inlet provided on the biochemical pool body, an inverted conical sludge sorting swirling sludge collection pit is formed at the bottom of the biochemical pool body, and the collection There is a mud discharge port in the center of the mud pit, and a horizontal water distribution pipe and a tangential jet head connected to the sewage inlet are distributed above the mud pit. The sewage inlet is set above the horizontal water distribution pipe and the tangential water jet head. There is at least one liquid riser, the outlet end of the air supply pipe extends below the liquid riser, and the inlet end protrudes out of the biochemical pool; the biochemical pool is divided into aerobic area, anoxic area, and anaerobic area from top to bottom. In the oxygen area, the water outlet is set above the aerobic area, and a baffle is provided near the water outlet in the biochemical pool, and the top of the baffle is higher than the water outlet on the pool body. The invention also relates to a treatment method using the treatment device, which has the characteristics of simple process, low cost and energy saving.

Description

Sewage biochemical treatment device and treatment method thereof

technical field

The invention belongs to the field of sewage treatment, and in particular relates to a sewage biochemical treatment device and a treatment method thereof. `` ``

Background technique

In recent years, my country's urban sewage treatment rate has been continuously increasing, but the problem of water eutrophication caused by nitrogen and phosphorus pollution has not only not been resolved, but has become increasingly serious. Therefore, the aggravation of water eutrophication puts forward strict requirements for the removal of nitrogen and phosphorus. It can be seen that the main contradiction of sewage treatment has changed from the removal of organic pollutants to the removal of nitrogen and phosphorus pollutants. my country's effluent standards for urban sewage treatment plants are getting higher and higher, especially the standards for nitrogen and phosphorus. Therefore, many urban sewage treatment plants that have been built need to be upgraded to increase facilities to remove nitrogen and phosphorus pollutants in sewage, so as to meet the national standard. According to the prescribed discharge standards, new sewage treatment plants must be constructed in accordance with the new standards. For the nitrogen and phosphorus removal process, the future development requirements are not limited to high nitrogen and phosphorus removal rates, but also require stable and reliable treatment effects, flexible process control and adjustment, and low investment and operation costs. At present, the biological nitrogen and phosphorus removal process is developing in this simple, efficient and economical direction.

At present, the sewage treatment system in most areas of our country has not been regionalized or integrated, and the pollution sources are in a state of decentralized treatment. The traditional activated sludge process and other continuous flow biochemical treatment processes are difficult to treat sewage with small water volume and large fluctuations. Therefore, the development of high-efficiency, low-consumption, and less-occupied water treatment processes has always been an important topic in the field of wastewater treatment. Due to its own advantages and the maturity of microbial immobilization technology in recent years, bio-integrated reactor technology has attracted more and more attention from the academic community, and has been successfully applied to the treatment of various wastewater. Compared with the traditional wastewater treatment process, this new reactor technology can reduce process equipment, reduce engineering cost, save operating cost, and reduce floor space, which has attracted great attention from the government and scientific and technological personnel.

At present, there are few studies on vertically segmented integrated biological treatment processes. Most of the existing sewage biochemical treatment methods and devices are horizontally segmented in space. The most important ones are the traditional activated sludge method and its variants: A-O method, A-A-O method, A-B method, various oxidation ditches, etc., plus secondary sedimentation tank effluent; SBR method is time-segmented, and different time reaction tanks play different roles; MSBR method is a mixture of spatial scoring segments and time segments to improve time. The disadvantage of segmentation is that the final effluent cannot be separated from the secondary settling tank, that is, the supernatant is discharged after the sludge settles down. Often due to the slow sludge settling speed, the processing capacity of the secondary settling tank is low, and the processing time is generally It accounts for one-half of the entire water treatment cycle.

The vertical segmented integrated biological treatment process is adopted for its short sewage treatment time, saving land, reducing energy consumption, reducing cost, and ensuring high-quality continuous water output.

Sun Fuhua invented a set of vertically segmented and integrated sewage biochemical treatment methods and corresponding devices. The bottom of the device forms an inverted conical sludge sorting and swirling sludge collection pit. There is a sludge discharge port in the center of the sludge collection pit. At least one laminated sliding filter well is arranged on the upper part of the biochemical pool body. The aeration plane makes the biochemical pool segmented into Anaerobic, aerobic, and anoxic zones form a vertical internal circulation. The sewage rises from the anaerobic sludge area below the aeration head and the aeration pipe network to the aerobic rising area of the three-phase flow above for aerobic aeration, and then passes through The ring-shaped skirt plate for blocking floating objects and the two-phase flow quiescent outlet area of the virtual secondary sedimentation tank enter the stacked slide filter outlet well or the laminated slide filter outlet weir, and are discharged from the outlet at the lower part of the well center.

The sewage is horizontally tangentially jetted from the bottom, so that the inverted cone at the bottom of the pool acts as a cyclone to sort the sludge microscopically. The power of the horizontal rotation required for the sorting comes from the function of water inflow. When necessary, water needs to be added. Under normal circumstances, it is not enough to rely on the function of water inlet to provide the power of horizontal rotation required for sorting, and it is necessary to add an underwater mechanical stirring propeller to ensure the power of horizontal rotation; in addition, the process adopts The device is not only equipped with a secondary sedimentation tank, but also has an annular skirt to block floating objects and at least one laminated slide filter outlet well or laminated slide filter outlet weir. It directly restricts the wide application of the vertical segmented integrated sewage biochemical treatment device in the field of sewage treatment.

Contents of the invention

The invention aims to provide a sewage biochemical treatment device and a treatment method thereof with simple process, low cost and energy saving.

Concrete technical scheme of the present invention is as follows:

A sewage biochemical treatment device, including an air supply pipe, a biochemical tank body, a water outlet and a sewage inlet arranged on the biochemical tank body, an inverted conical sludge sorting swirling sludge collection pit is formed at the bottom of the biochemical tank body, and the center of the sludge collection pit is set There is a mud outlet, and above the mud pit, there are horizontal water distribution pipes and tangential water jets connected to the sewage inlet. The sewage inlet is set above the horizontal water distribution pipe and tangential water jets. There is at least one riser pipe, the outlet end of the air supply pipe extends below the riser pipe, and the inlet end protrudes outside the body of the biochemical pool; the biochemical pool body is divided into aerobic area, anoxic area, and anaerobic area from top to bottom. The water outlet is set above the aerobic area, and a baffle is arranged near the water outlet in the biochemical pool body. The baffle is parallel to the pool wall and extends around the biochemical pool body. The top of the baffle is higher than the top of the pool body. the water outlet.

In the present invention, the pipe spacing, height and cross-sectional size of the liquid riser can be set according to needs. Preferably, the pipe distance of the liquid riser is 3m, and the cross-sectional area of the liquid riser is equal to the cross-sectional area of the biochemical pool body. The ratio is 1:36, and the ratio of the height of the liquid riser to the height of the biochemical pool body is 3:8. The height of the liquid riser in the present invention can be selected according to the characteristics of the sewage. When the height of the liquid riser is large, it can be inserted deeper into the biochemical pool body. At this time, the ability to treat COD is strong. When the height of the liquid riser is small, It can be inserted into the shallower part of the biochemical pool, at this time the ability to process NH ₄ ⁺ is strong.

The aerobic zone is provided with a packing frame, and the height of the packing frame accounts for 1/2 of the height of the biochemical pool body. A filler is arranged on the filler frame as an aerobic biological carrier, and the material of the filler is polypropylene. Using high-quality polypropylene material, soaking in waste water for a long time will not degrade and will not be toxic to microorganisms; the filler is set on the filler frame and suspended in the water, which has good adaptability to the change of sewage water quality and water quantity; It is easy to replace and has a long service life.

The air inlet end of the air supply pipe is connected with a fan.

The present invention also relates to a treatment method using the above sewage biochemical treatment device, comprising the following steps:

(1) After the sewage enters the horizontal water distribution pipe from the sewage inlet, it is ejected from the tangential jet head under the action of momentum, driving the sludge at the bottom of the inverted cone surface to make a horizontal swirl movement, and concentrates to the center of the mud pit. The old sewage with a large proportion The sludge is concentrated faster than the new sludge, so as to realize the microscopic separation and discharge of the sludge;

(2) The biochemical pool body is divided into aerobic zone, anoxic zone, and anaerobic zone from top to bottom. The sewage rises from the anaerobic zone to the anoxic zone, and then enters the aerobic zone from the anoxic zone and then exits with the air supply pipe. The compressed air at the end is mixed and flows upwards along the riser pipe;

(3) Part of the water from the top of the riser flows back and circulates vertically in the aerobic zone. After a part of the water is blocked by the baffle, the sludge in the sewage slides down the pool wall to the bottom of the pool, and the clean water slowly rises along the pool wall and passes through the pool. After the virtual sedimentation tank formed by the wall and the baffle, it flows out from the water outlet on the upper part of the tank body.

The air supply volume of the above-mentioned air supply pipe is preferably 41-42m ³ /hour.

In the present invention, the sewage to be treated is microscopically sorted by the horizontal water distribution pipe at the bottom and the horizontal tangential water jet from the tangential jet head, so that the inverted cone surface at the bottom of the pool acts as a cyclone to sort the sludge microscopically. The sewage inlet is set as It is higher than the horizontal water distribution pipe and the tangential jet head, and the impact of the sewage is used to make the water shoot out from the tangential jet head, providing sufficient horizontal rotation for microscopic separation of sludge without the need for underwater mechanical stirring propellers The powerful power makes the incoming sewage and sludge fully mixed, prevents sludge from settling, saves energy and reduces costs.

The invention adopts the aeration method of feeding compressed air into the liquid riser instead of the traditional aeration plane, and introduces the compressed air into the liquid riser. Since the specific gravity of the water containing air is small, the sewage and the gas are pushed along the liquid riser. Upward flow, while oxygen in the air is transferred to the sewage. The water flow direction outside the riser is vertically downward, and the oxygen-enriched water is sent underwater by utilizing the vertical circulation of water. While the water is flowing down, the activated sludge in the filler breathes and consumes oxygen, and then forms an oxygen concentration gradient in the biochemical tank in which the oxygen concentration gradually decreases. At a certain depth, the oxygen concentration is equal to zero. This process realizes nitrification and denitrification biochemical reaction. This aeration method can reduce the size of the bubbles, increase the surface area, and greatly enhance the transfer efficiency of oxygen to the liquid. Due to the increase in oxygen concentration, the penetration depth of oxygen in the sludge floc particles is increased, making the flocs The proportion of aerobic microorganisms increases, and the sludge activity is maintained at a high level, so the purification function is good, and there will be no filamentous bacteria sludge swelling caused by lack of oxygen, the mud particles are stronger, and the sludge concentration is greatly increased. Improvement; the growth of nitrifying bacteria will not be limited by the lack of dissolved oxygen, which is beneficial to the biological denitrification process, so as to achieve the purpose of strengthening denitrification.

Compared with the prior art, the present invention has the following advantages:

(1) The present invention uses the vertical circulation of waste water to cooperate with the filler to form an oxygen concentration gradient in the vertical direction, which is beneficial to biological denitrification, thereby achieving the purpose of strengthening denitrification; reducing energy consumption and improving oxygen utilization efficiency;

(2) Set the sewage inlet higher than the horizontal water distribution pipe and the tangential jet head, and use the impact of the sewage to make the water shoot out from the tangential jet head, so as to provide sufficient horizontal rotation power for the microscopic separation of the sludge, without the need The underwater mechanical stirring propeller is used to save energy and reduce costs;

(3) The present invention is simple in structure and low in cost. The air supply pipe is directly inserted into the liquid riser, and the air supply pipe only needs to be taken out during maintenance without entering the tank body, which is convenient for maintenance; For the agitation of sludge settlement, the virtual sedimentation tank formed by the baffle plate and the pool wall is used to complete the sedimentation of the sludge. The structure is simple and the cost is low, which is suitable for large-scale application in the field of sewage treatment;

(4) The present invention can carry out targeted treatment on different types of sewage by controlling the height of the riser; if the concentration of COD in the sewage is high, the depth of the riser should be deeper (the height of the riser is relatively large) ; If the concentration of NH ₄ ⁺ in the sewage is high, the depth of the riser is shallower (the height of the riser is relatively small), so as to realize the multi-purpose of one thing and meet the requirements of different sewage treatment.

Description of drawings

Fig. 1 is a schematic diagram of the structure of the present invention.

Among them: 1 is the water outlet, 2 is the baffle, 3 is the packing frame, 4 is the liquid riser, 5 is the air supply pipe, 6 is the fan, 7 is the water distribution pipe, 8 is the jet head, 9 is the mud discharge port, 10 is Sewage inlet, 11 is filler, 12 is water inlet pipe, 13 is biochemical tank body, A is aerobic zone, B is anoxic zone, C is anaerobic zone, D is sludge zone.

Detailed ways

Further illustrate the present invention below in conjunction with accompanying drawing.

Referring to Fig. 1, sewage biochemical treatment device of the present invention comprises air supply pipe 5, biochemical pool body 13, water outlet 1 and sewage inlet 10 that are located on biochemical pool body 13, biochemical pool body 13 inner bottoms form an inverted conical sewage Sludge sorting swirling sludge collection pit, the sludge collection pit is the sludge area D, and the sludge is concentrated in the D area after settlement. There is a sludge discharge port 9 in the center of the sludge collection pit, and a horizontal water distribution pipe 7 and a tangential jet head 8 are distributed above the sludge collection pit. , the horizontal water distribution pipe 7 and the tangential water jet head 8 are connected to the sewage inlet 10 through the water inlet pipe 12, and the sewage inlet 10 is arranged above the horizontal water distribution pipe 7 and the tangential water jet head 8. The vertical direction above the biochemical pool body 13 is provided with at least one liquid-rising pipe 4, the gas outlet end of the air supply pipe 5 stretches into the below of the liquid-rising pipe 4, and its air inlet protrudes out of the biochemical pool body 13 to be connected with the blower fan 6; The biochemical pool body 13 is divided into aerobic zone A, anoxic zone B, and anaerobic zone C from top to bottom. The water outlet 1 is located above the aerobic zone A and slightly higher than the upper end of the liquid riser. The body 13 is provided with a baffle 2 near the water outlet 1. The baffle 2 is connected to the biochemical pool body 13 through a bracket. Since this connection method is existing, it will not be described in detail. The baffle 2 is parallel to the pool wall and along the The surroundings of the biochemical pool body 13 extend, and the top of the baffle plate 2 is higher than the water outlet 1 on the biochemical pool body 13 .

In the present invention, the pipe spacing, height and cross-sectional size of the liquid riser can be set according to needs. Preferably, the pipe distance of the liquid riser is 3m, and the cross-sectional area of the liquid riser is equal to the cross-sectional area of the biochemical pool body. The ratio is 1:36, and the ratio of the height of the liquid riser to the height of the biochemical pool body is 3:8.

The aerobic zone A is provided with a packing frame 3, and the height of the packing frame accounts for 1/2 of the height of the biochemical tank body. The filler is distributed on the filler frame, and the filler is an existing filler, and its material can be polypropylene.

Adopt the processing method of above-mentioned sewage biochemical treatment device, comprise the steps:

(1) After the sewage enters the horizontal water distribution pipe from the sewage inlet, it is ejected from the tangential jet head under the action of momentum, driving the sludge at the bottom of the inverted cone surface to make a horizontal swirl movement, and concentrates to the center of the mud pit. The old sewage with a large proportion The sludge is concentrated faster than the new sludge, so as to realize the microscopic separation and discharge of the sludge;

(2) The biochemical pool body is divided into aerobic zone, anoxic zone, and anaerobic zone from top to bottom. The sewage rises from the anaerobic zone to the anoxic zone, and then enters the aerobic zone from the anoxic zone and then exits with the air supply pipe. The compressed air at the end is mixed and flows upwards along the riser pipe;

(3) Part of the water from the top of the riser flows back and circulates vertically in the aerobic zone. After a part of the water is blocked by the baffle, the sludge in the sewage slides down the pool wall to the bottom of the pool, and the clean water slowly rises along the pool wall and passes through the pool. After the virtual sedimentation tank formed by the wall and the baffle, it flows out from the water outlet on the upper part of the tank body.

The air supply volume of the above-mentioned air supply pipe is preferably 41-42m ³ /hour.

Example

Biochemical pool body 13 is cylindrical, and its diameter is 3m, and height is 8m; The vertical direction of the center of biochemical pool body inserts a diameter and is the riser pipe of 50cm, and the height of riser pipe is 3m; The height of the frame is 4m, and the upper end of the liquid riser is slightly higher than the upper end of the packing frame; the air supply volume of the air supply pipe is 41-42m ³ /hour; the sewage treatment capacity of the biochemical tank is 10m ³ /hour. COD 200mg/L, NH ₄ ⁺ 20mg/L in the sewage entering from the sewage inlet; after being treated by the sewage biochemical treatment device of the present invention, COD 60mg/L, NH ₄ ⁺ 8mg/L in the water flowing out from the water outlet, reaching the national discharge standard.

Claims (6)

1. A sewage biochemical treatment device, comprising an air supply pipe, a biochemical tank body, a water outlet and a sewage inlet arranged on the biochemical tank body, an inverted conical sludge sorting swirling sludge collection pit formed at the bottom of the biochemical tank body, and a sludge collection pit There is a mud discharge port in the center, and a horizontal water distribution pipe and a tangential jet head connected to the sewage inlet are distributed above the mud collection pit. It is characterized in that the sewage inlet is arranged above the horizontal water distribution pipe and the tangential water jet head, at least one liquid riser is arranged vertically above the biochemical pool body, and the gas outlet end of the air supply pipe extends below the liquid riser, Its air inlet protrudes out of the body of the biochemical pool; The biochemical pool body is divided into aerobic area, anoxic area and anaerobic area from top to bottom. The water outlet is set above the aerobic area. Parallel and extending around the biochemical pool body, the top of the baffle is higher than the water outlet on the pool body. 2. The sewage biochemical treatment device according to claim 1, characterized in that the pipe spacing of the liquid riser is 3m, the cross-sectional area ratio of the liquid riser and the biochemical pool body is 1:36, and the liquid riser is 1:36. The ratio of the height of the tube to the height of the biochemical pool body is 3:8. 3. The sewage biochemical treatment device according to claim 1 or 2, characterized in that the aerobic zone is provided with a filler frame, and the height of the filler frame accounts for 1/2 of the height of the biochemical tank body. 4. The sewage biochemical treatment device according to claim 1, characterized in that the air inlet end of the air supply pipe is connected to a fan. 5. The treatment method of the sewage biochemical treatment device according to any one of the above claims, characterized in that it comprises the following steps: (1) After the sewage enters the horizontal water distribution pipe from the sewage inlet, it is ejected from the tangential jet head under the action of momentum, driving the sludge at the bottom of the inverted cone surface to make a horizontal swirl movement, and concentrates to the center of the mud pit. The old sewage with a large proportion The sludge is concentrated faster than the new sludge, so as to realize the microscopic separation and discharge of the sludge; (2) The biochemical pool body is divided into aerobic zone, anoxic zone, and anaerobic zone from top to bottom. The sewage rises from the anaerobic zone to the anoxic zone, and then enters the aerobic zone from the anoxic zone and then exits with the air supply pipe. The compressed air at the end is mixed and flows upwards along the riser pipe; (3) Part of the water from the top of the riser flows back and circulates vertically in the aerobic zone. After a part of the water is blocked by the baffle, the sludge in the sewage slides down the pool wall to the bottom of the pool, and the clean water slowly rises along the pool wall and passes through the pool. After the virtual sedimentation tank formed by the wall and the baffle, it flows out from the water outlet on the upper part of the tank body. 6. The treatment method according to claim 5, characterized in that the air supply volume of the air supply pipe is 41-42m ³ /hour.

Images