CN204490603U - The reaction unit of phosphate from sewage is efficiently removed without anaerobic phosphorus release - Google Patents

Abstract

The utility model provides a kind of reaction unit and the treatment process of efficiently removing phosphate from sewage without anaerobic phosphorus release, and this device is provided with reactor, DO detection instrument, DO sensor, aeration plate, under meter, water-bath, recycle pump, top go out water pump, gas blower and Controlling System; This device biofilm carrier cost is low, and easy attached microbial, can shorten the startup cycle; After process, water enters support tube inside by capillary action, and biological membrane assembly has filteration, without the need to arranging settling tank; Intelligent control system controls gas blower and replaces start and stop, makes reactor be in (aerobic/anoxic) alternately ⁿenvironment, realizes the non-traditional efficient dephosphorization without anaerobic phosphorus release; The denitrification dephosphorization of anoxic condition, reduces carbon source requirement; What intelligent control system was implemented replaces (aerobic/anoxic) ⁿaeration strategy, shortens aeration time, decreases power consumption, has saved the energy.

Description

Reaction device for efficient removal of phosphate in sewage without anaerobic phosphorus release

technical field

The utility model relates to the application field of water treatment technology, specifically a reaction device for efficiently removing phosphate in sewage without anaerobic phosphorus release.

Background technique

 With the increase of my country's total wastewater discharge and the widespread use of chemical fertilizers, synthetic detergents and pesticides, nitrogen and phosphorus have gradually become the main pollutants in water bodies. Eutrophication of water bodies caused by nitrogen and phosphorus pollutants—algae blooms and red tides have further led to the deterioration of water quality, which not only affects the use of water bodies, but also endangers human health, and increases the difficulty of water supply treatment. Algae overgrowth is a typical feature of water eutrophication. Although both nitrogen and phosphorus may become limiting factors for algae growth, the relationship between algae's nitrogen and phosphorus needs is more urgent. If the water body is deficient in nitrogen, it can be supplemented by nitrogen-fixing microorganisms in the water, such as certain nitrogen-fixing bacteria and cyanobacteria. As long as there is a low concentration of phosphorus 0.018 mg/L in the water body, it can stimulate algal blooms. When the total phosphorus TP concentration in water was lower than 0.1 mg/L, the biomass of phytoplankton increased linearly with the increase of TP concentration. In most lakes and reservoirs, phosphorus is the main limiting nutrient element, and controlling the phosphorus load on water bodies has become the key to controlling eutrophication. Therefore, the regulations on phosphorus discharge standards in various countries in the world are becoming increasingly strict. The phosphorus content stipulated in my country's "Pollutant Discharge Standards for Urban Sewage Treatment Plants" GB19819-2002, the first-level A standard is: TP is less than 0.5mg/L, and the first-level B standard For: TP is less than 1mg/L. It can be seen that both existing sewage plants and new sewage plants are facing the problem of deep phosphorus removal from sewage.

At present, the treatment technologies for phosphorus removal in sewage are mainly divided into physical adsorption method, chemical precipitation method and biological method. Phosphorus removal by physical adsorption is a process of utilizing the affinity of certain porous or large specific surface area solid substances to phosphate ions in water to achieve phosphorus removal. Phosphorus removal by adsorption method still has many problems in terms of anti-interference of adsorbent, dissolution loss and regeneration. Therefore, the adsorption method is usually used as an auxiliary phosphorus removal method, and it is difficult to be widely used as the main phosphorus removal method. The basic principle of chemical precipitation phosphorus removal is to form insoluble phosphate precipitates by adding metal salt chemicals, and then remove them from sewage by solid-liquid separation. The main problems are expensive chemicals, high operating costs, and chemical sludge. Large output, difficult sludge disposal, etc., are subject to certain restrictions in practical application. The enhanced biological phosphorus removal process is currently the most widely used phosphorus removal technology in sewage. The research and application of the process began in the late 1950s. With the deepening of research and popularization of applications, the types of processes continue to increase. Overall, the cost of enhanced biological phosphorus removal is low, especially for wastewater with low phosphorus concentration. Commonly used enhanced phosphorus removal processes include A/O process, A ² /O process, oxidation ditch process, UCT process, etc. However, these processes have disadvantages such as complex process flow, difficult control of operating parameters, and difficult disposal of excess sludge.

The SBBR process combines the advantages of the sequencing batch process and the biofilm process. Through the control of different processes such as anaerobic, anoxic, and aerobic, the process of nitrogen and phosphorus removal is completed in one reactor, and the integration of sewage treatment is realized. Its main advantages are small footprint, high treatment efficiency, large treatment capacity and stable operation, and less residual sludge. However, SBBR filler selection and operation mode control are the key factors that affect system processing performance and daily operation cost. Filler is a key component of biofilm reactor, which directly affects the performance and treatment efficiency of biofilm reactor. At present, the main fillers used in SBBR include mobile activated carbon, polypropylene suspension balls, etc., fixed ceramsite, iron filings, soft fibers, polyethylene, etc. For example, the domestic patent CN1709810 uses iron filings as filler, which has the advantages of no clogging and strong impact resistance, but the filler layer does not have a filtering effect. Patent CN101168461 uses a stainless steel or filter cloth filter with an average pore size of 10-200 μm as a biofilm filter to replace the traditional secondary sedimentation tank for mud-water separation. The formed biofilm has filtering performance, but the pore size of the carrier filter is easy to block, and biological Membrane renewal is slow, regular backwashing is required, and the maintenance and management of daily operation is relatively complicated. In the patent CN101863590A, a combined anoxic/aerobic bio-enhanced activated carbon dynamic membrane is used to remove phosphorus, and the treated domestic sewage is filtered through the dynamic membrane pre-coated with bio-enhanced activated carbon. The initial investment of this process is high, and the daily operation is difficult. High difficulty. Although bio-augmented activated carbon has large dynamic membrane flux and short hydraulic retention time, the process design is complicated. The operation mode of SBBR determines the demand for carbon source and power consumption of the system. Conventional anaerobic/aerobic SBBR and anaerobic/anoxic/aerobic SBBR have high demand for carbon source and high power consumption. The fact that sewage treatment "uses energy to consume energy" cannot be changed. Alternating anaerobic/aerobic conditions are not necessary for successful biological phosphorus removal. Therefore, the classic phosphorus removal theory - anaerobic phosphorus release and aerobic excess phosphorus uptake has been questioned. Therefore, it is necessary to develop a new SBBR phosphorus removal process with low carbon consumption and low energy consumption.

To sum up, in SBBR, the selection of fillers has the problems of slow biofilm renewal, no filtration performance, or although it has filtration performance, it is easy to clog and requires backwashing. Moreover, in the sewage biological phosphorus removal process, there are also problems such as complex process design, difficult maintenance and management, large carbon source demand, and high energy consumption, which affect the practical application of biological phosphorus removal.

Utility model content

Aiming at the shortcomings of the above-mentioned existing technologies for phosphorus removal in sewage, such as slow regeneration of biofilms, no filtration performance, or easy clogging and need for backwashing and other defects although it has filtration performance, the utility model provides a non-anaerobic phosphorus release high-efficiency Reaction device for removing phosphate in sewage.

In order to solve the problems of the technologies described above, the technical solution adopted in the utility model is:

A reaction device for efficiently removing phosphate in sewage without anaerobic phosphorus release. The device is equipped with a reactor, DO detector, DO sensor, aeration pan, flow meter, water bath, circulation pump, upper outlet pump, blower and control system ;

The reactor includes a reaction tank and a biofilm module hung in the reaction tank. The upper part of the side wall of the reaction tank is connected with a relatively arranged water inlet pipe and a circulating water outlet pipe, and the bottom of the side wall is connected with a relatively arranged circulating water inlet pipe and The bottom water outlet pipe, and the water inlet pipe and the bottom water outlet pipe, the circulating water inlet pipe and the circulating water outlet pipe are all arranged on both sides of the reaction tank. On the pipeline between the circulating water inlet pipe and the circulating water outlet pipe, the aeration pan is arranged at the bottom of the reaction tank, and is connected to the blower outside the reactor through the conduit, and the blower is connected to the control system, and the flowmeter is set at On the pipeline between the aeration pan and the blower, one end of the DO detector is arranged in the reaction tank, and the other end is connected to the DO sensor, and the DO sensor is connected to the control system;

The biofilm assembly includes a support plate, an upper outlet pipe, a water collection tube and soft fibers, the support plate is hung on the top of the side wall of the reaction tank, the two ends of the water collection tube are sealed, and the sealing cover provided on the upper part and the support plate Fixed connection, the upper water outlet pipe is inserted into the water collecting cylinder through the sealing cover on the upper part of the water collecting cylinder and extends to the bottom of the water collecting cylinder, the top of the upper water outlet pipe is connected with the upper water outlet pump, and the bottom of the side wall of the water collecting cylinder is provided with a water outlet, the water outlet The conduit is connected with the outlet pipe at the bottom, and a number of small filter holes are opened on the side wall of the water collection cylinder. One end of the soft fiber is set in the filter holes, and the other end extends freely to the outside of the water collection cylinder;

The soft fiber adopts blended cotton thread or synthetic fiber, and its diameter is 0.5mm~2mm;

The water collecting cylinder is a plexiglass or polypropylene or polyethylene plastic cylinder with a wall thickness of 3-8mm;

The diameter of the filter holes is 4-6mm, and the center distance of the filter holes is 20-30mm;

The reaction tank is square or circular, and the volume of the biofilm module accounts for 1/5 of the effective volume of the tank;

The distance between the water outlet and the bottom of the water collecting tube is 1 mm;

The beneficial effects of the utility model:

The utility model provides a reaction device and treatment method for efficiently removing phosphate in sewage without anaerobic phosphorus release. The membrane module has the function of filtering, and there is no need to set up a sedimentation tank; the intelligent control system controls the blower to start and stop alternately, so that the reactor is in an alternate (aerobic/anoxic) ⁿ environment, realizing non-traditional efficient phosphorus removal without anaerobic phosphorus release; The denitrification and phosphorus removal in the anoxic state reduces the demand for carbon sources; the alternate (aerobic/anoxic) ⁿ oxygen supply strategy implemented by the intelligent control system shortens the aeration time, reduces power consumption, and saves energy; The hydraulic retention time is short, which reduces the volume and floor space of the reactor, which can reduce the initial investment; the intelligent control reactor used to implement the phosphorus removal method in sewage of the utility model is simple to manufacture, easy to operate, and automatically controlled; the utility model The power consumption and carbon source requirement of phosphorus removal in sewage are reduced, the initial investment is reduced, and the treatment efficiency is improved, thereby improving the practicability of phosphorus removal in non-traditional high-efficiency sewage without anaerobic phosphorus release.

Description of drawings

Fig. 1 is the structural representation of the utility model reaction device;

Fig. 2 is a structural plan view of the reactor of the utility model;

Fig. 3 sectional view of reactor structure A-A of the present utility model;

Fig. 4 B-B sectional view of reactor structure of the present utility model;

Fig. 5 is a structural schematic diagram of the biofilm module of the utility model;

Reference signs: 1. Reaction tank, 2. Biofilm module, 3. DO detector, 4. Water inlet pipe, 5. DO sensor, 6. Circulating water outlet pipe, 7. Circulating water inlet pipe, 8. Aeration disc, 9 , Bottom outlet pipe, 10, Vent pipe, 11, Flow meter, 12, Water bath, 13, Circulation pump, 14, Upper outlet pump, 15, Blower, 16, Control system, 2-1, Support plate, 2- 2. Upper water outlet pipe, 2-3, water collecting cylinder, 2-4, small filter holes, 2-5, soft fiber, 2-6, water outlet.

Detailed ways

The utility model is further elaborated below in conjunction with specific embodiments.

As shown in the figure: a reaction device for efficiently removing phosphate in sewage without anaerobic phosphorus release, the device is equipped with a reactor, a DO detector 3, a DO sensor 4, an aeration disc 8, a flow meter 11, a water bath 12, Circulation pump 13, upper outlet pump 14, air blower 15 and control system 16;

The reactor includes a square reaction tank 1 and a biofilm module 2 suspended in the reaction tank 1, wherein the volume of the biofilm module 2 accounts for 1/5 of the effective volume of the water tank, and the upper part of the side wall of the reaction tank 1 is connected with an opposite device. The water inlet pipe 4 and the circulating water outlet pipe 6, the bottom of the side wall are connected with the oppositely arranged circulating water inlet pipe 7 and the bottom outlet pipe 9, and the water inlet pipe 4 and the bottom outlet pipe 9, the circulating water inlet pipe 7 and the circulating water outlet pipe 6 are all opposite It is arranged on both sides of the reaction tank 1, and the circulating water inlet pipe 7 and the circulating water outlet pipe 6 are communicated through conduits outside the reactor, and the water bath 12 and the circulating pump 13 are arranged on the pipeline between the circulating water inlet pipe 7 and the circulating water outlet pipe 6, The aeration pan 8 is arranged at the bottom of the reaction tank 1, and is connected to the blower 15 outside the reactor through a conduit, the blower 15 is connected to the control system 16, and the flow meter 11 is arranged between the aeration pan 8 and the blower 15 On the pipeline between, one end of the DO detector 3 is arranged in the reaction tank 1, and the other end is connected with the DO sensor 4, and the DO sensor 4 is connected with the control system 16;

The biofilm module 2 includes a support plate 2-1, an upper outlet pipe 2-2, a plexiglass water collection cylinder 2-3 with a wall thickness of 3-8mm, and a blended cotton soft fiber 2-5 with a diameter of 0.5mm-2mm , the support plate 2-1 is hung on the top of the side wall of the reaction tank 1, the two ends of the water collection tube 2-3 are sealed, and the sealing cover provided on the upper part is fixedly connected with the support plate 2-1, and the upper outlet pipe 2-2 The sealing cover on the upper part of the water collecting tube 2-3 is inserted in the water collecting tube 2-3 and extends to the bottom of the water collecting tube 2-3, the top of the upper water outlet pipe 2-2 is connected with the upper water outlet pump 14, and the water collecting tube 2-3 The side wall of the bottom 1mm is provided with a water outlet 2-6, and the water outlet 2-6 is connected with the bottom outlet pipe 9 through a conduit, and the side wall of the water collection tube 2-3 is provided with a number of filters with a diameter of 5mm and a center distance of 25mm. Aperture 2-4, one end of soft fiber 2-5 is arranged in filter aperture 2-4, and the other end extends freely to the outside of water collection cylinder 2-3.

A method for removing phosphate in sewage by using the above-mentioned reaction device, the control system continuously measures the DO value in the reaction tank 1 through the DO detector 3 and the DO sensor 4, when the DO value is less than the set lower limit DO value Start the aeration pan 8 for aeration, stop the aeration pan 8 until the DO value is greater than the set lower limit DO value, and start the circulation pump 13 at the same time to make the water circulate in the reaction tank 1 through the circulation water inlet pipe 7 and the circulation water outlet pipe 6 , when the DO value is less than the set lower limit DO value, the circulation pump 13 is stopped, and the aeration disc 8 is started again at the same time for aeration, so that an alternate aerobic and anoxic environment is formed in the reaction tank 1, thereby improving the efficiency of phosphorus-accumulating bacteria. Oxygen-absorbing phosphorus and denitrifying phosphorus-accumulating bacteria take up phosphorus in anoxic conditions to achieve efficient phosphorus removal in sewage;

The above-mentioned DO detector is a water quality dissolved oxygen measuring instrument, and the DO sensor is a water quality dissolved oxygen sensor.

The method on which the utility model is based belongs to the biofilm treatment method, which uses phosphorus-accumulating bacteria to absorb phosphorus aerobically, absorbs phosphorus through anoxic denitrification, and realizes phosphorus removal in sewage. The specific theoretical basis for phosphorus removal is:

In the aerobic stage, phosphorus-accumulating bacteria use oxygen as the electron acceptor to decompose poly-β-hydroxybutyrate PHB and liver glycogen stored in the body to provide energy for cell growth and reproduction, and at the same time, a part of the energy can be actively absorbed by phosphorus-accumulating bacteria Phosphate, and stored in the body in the form of polyphosphate for growth needs, this is the phenomenon of aerobic phosphorus uptake by phosphorus accumulating bacteria.

Phosphorus uptake reaction equation in aerobic stage is as follows:

(1)

In the anoxic stage, the facultative phosphorus-accumulating bacteria enriched in the reactor use NO ^3- and oxygen as electron acceptors, use the liver glycogen synthesized in the body as energy substances, and store phosphoric acid in sewage in the form of polyphosphate Salt in the body, to achieve phosphorus removal in sewage.

The denitrification phosphorus removal reaction equation in the anoxic stage is as follows:

(2)

Therefore, use the intelligent control system to create an alternately operating aerobic/anoxic environment, enrich the aerobic phosphorus-accumulating bacteria and facultative phosphorus-accumulating bacteria in the reactor, and realize the non-traditional non-anaerobic phosphorus-releasing wastewater removal. Phosphorus; denitrification and phosphorus removal in the anoxic stage does not require external carbon sources, reducing the demand for carbon sources, (aerobic/anoxic) ⁿ alternate operation, intermittent aeration, reducing power consumption and saving energy.

The control mechanism of the intelligent control system is: under different temperature conditions, the nitrification and denitrification reaction time under the current temperature condition is determined according to the slope of the dissolved oxygen in the reactor, and the nitrification of the denitrification process is completed for the nitrifying bacteria and denitrifying bacteria Control the denitrification and phosphorus removal time of phosphorus absorption and release, and then control the DO value of the system to achieve the purpose of nitrogen and phosphorus removal; the control method of the intelligent control system: continuously measure the DO value in the reactor → calculate the microbial Breathing speed → calculate the amount of oxygen required for microbial respiration in the next reaction cycle → control the aeration time.

After the intelligent control SBBR is started, the system enters the calculation stage, which includes the aeration stage and the anoxic stage. In the aeration stage, after the aeration device is aerated for 30 minutes, if DO≥low limit DO value, stop aeration if DO≤low limit When the DO value is reached, the aeration device continues to run for 10 minutes, and then compares it with the lower limit DO value again until DO ≥ the lower limit DO value, and then starts the reflux device. After the device continues to run for 10 minutes, it is compared with the lower limit DO value again until it meets DO≤lower limit DO value. During this calculation process, the software determines the nitrification, denitrification and phosphorus removal at this temperature according to the slope of DO in the reactor. The time for the bacterial absorption and release of phosphorus reaction is the aerobic and anoxic time in the reaction stage, and the calculated nitrification and denitrification time is subtracted from the aeration and anoxic reflux time in the calculation stage, which is the aeration time T in the reaction stage ₁ and anoxic time T ₂ ; the reaction stage takes 2h as a reaction cycle, that is, the sum of aeration time T ₁ and anoxic time T ₂ is 120min, and, in different cycles, the values of T ₁ and T ₂ are different, The values of T ₁ and T ₂ vary with the water temperature and DO concentration in the reactor; in the utility model, the lower limit DO is set to 0.5 mg/L, so even in the stage of stopping aeration, the minimum value of DO in the reactor is 0.5 mg/L, in anoxic state, therefore, there is no anaerobic state during the operation of the reactor.

The water to be treated flows in from the water inlet pipe 4 on the upper part of the side wall of the reactor to control the alternate (aerobic/anoxic) ⁿ environment. The microbial sludge age on the biofilm is kept at about 25d, and the hydraulic retention time is 4-6h. Water enters the inside of the water collecting tube 2-3 through capillary action, and the outlet water is extracted from the upper water outlet pipe 2-2 in the water collecting tube 2-3 through the upper water outlet pump 14, or from the water outlet on the bottom side wall of the water collecting tube 2-3 by gravity 2-6 outflow, the arrow direction in Figure 1 is the water flow direction.

The utility model is suitable for treating urban sewage, domestic sewage, food waste water, or chemical waste water with similar water quality.

The composition of synthetic urban sewage is: COD300 mg/L, TN30 mg/L, TP5 mg/L, C/N is 10.0, C/P is 60.0, pH is 6.8-7.2, the average value of HRT wastewater in the reactor The residence time is 6 hours, and the temperature is controlled at 25±1°C. The non-anaerobic phosphorus release reaction device of the utility model is used to efficiently remove phosphate in sewage. The aeration system is controlled by an intelligent control system, and the intelligent control system is implemented. Control the operation of the reactor to create an alternate (aerobic/anoxic) ⁿ environment. The TP concentration in the effluent is 0.02 mg/L, which is lower than the first-class A standard of the "Pollutant Discharge Standard for Urban Sewage Treatment Plants" GB89198-2002.

Claims (6)

1. efficiently remove the reaction unit of phosphate from sewage without anaerobic phosphorus release, it is characterized in that: this device is provided with reactor, DO detection instrument (3), DO sensor (4), aeration plate (8), under meter (11), water-bath (12), recycle pump (13), top go out water pump (14), gas blower (15) and Controlling System (16);

Described reactor comprises reactive tank (1) and is hung on the biological membrane assembly (2) in reactive tank (1), the top of reactive tank (1) sidewall is connected with the water inlet pipe (4) and recycling outlet (6) that are oppositely arranged, the bottom of sidewall is connected with the circulation water inlet pipe (7) and bottom rising pipe (9) that are oppositely arranged, and water inlet pipe (4) and bottom rising pipe (9), circulation water inlet pipe (7) and recycling outlet (6) are all oppositely arranged on the both sides of reactive tank (1), circulation water inlet pipe (7) is communicated with through conduit in reactor is outer with recycling outlet (6), water-bath (12) and recycle pump (13) are arranged on the pipeline between circulation water inlet pipe (7) and recycling outlet (6), described aeration plate (8) is arranged on the bottom in reactive tank (1), and be connected with the gas blower (15) outside reactor through conduit, gas blower (15) is connected with Controlling System (16), described under meter (11) is arranged on the pipeline between aeration plate (8) and gas blower (15), one end of described DO detection instrument (3) is arranged in reactive tank (1), the other end is connected with DO sensor (4), DO sensor (4) is connected with Controlling System (16),

Described biological membrane assembly (2) comprises back up pad (2-1), top rising pipe (2-2), Water collecting tube (2-3) and soft fiber (2-5), described back up pad (2-1) is hung on the top of reactive tank (1) sidewall, Water collecting tube (2-3) two ends seal, and the sealing cover that its top is arranged is fixedly connected with back up pad (2-1), top rising pipe (2-2) sealing cover through Water collecting tube top to be plugged in Water collecting tube (2-3) and to extend to Water collecting tube (2-3) bottom, top and the top of top rising pipe (2-2) go out water pump (14) and are connected, the bottom of Water collecting tube (2-3) sidewall is provided with water outlet (2-6), water outlet (2-6) is communicated with bottom rising pipe (9) by conduit, the sidewall of Water collecting tube (2-3) offers some filtration apertures (2-4), one end of soft fiber (2-5) is arranged on filters in aperture (2-4), the other end freely extends outward to Water collecting tube (2-3).

2. the reaction unit efficiently removing phosphate from sewage without anaerobic phosphorus release as claimed in claim 1, it is characterized in that: described soft fiber (2-5) adopts blending cotton thread or synthon, its diameter is 0.5mm ~ 2mm.

3. the reaction unit efficiently removing phosphate from sewage without anaerobic phosphorus release as claimed in claim 1, is characterized in that: described Water collecting tube (2-3) is synthetic glass or polypropylene, vinyon cylinder, wall thickness 3 ~ 8mm.

4. the reaction unit efficiently removing phosphate from sewage without anaerobic phosphorus release as claimed in claim 1, is characterized in that: described filtration aperture (2-4) diameter is 4 ~ 6mm, and filtering aperture (2-4) between centers is 20 ~ 30mm.

5. the reaction unit efficiently removing phosphate from sewage without anaerobic phosphorus release as claimed in claim 1, is characterized in that: described reactive tank (1) is for square or circular, and the volume of biological membrane assembly (2) accounts for 1/5 of tank effective volume.

6. the reaction unit efficiently removing phosphate from sewage without anaerobic phosphorus release as claimed in claim 1, is characterized in that: described water outlet (2-6) is 1mm with the distance of Water collecting tube (2-3) bottom.