Electrocoagulation coupled gravity-driven water purification device and method of use thereof

Abstract

The present application relates to the field of sewage advanced treatment, and provides an electric flocculation coupled gravity-driven water purification device and a use method thereof.The device comprises a raw water storage pool, a water outlet pump, an electric flocculation pool, a constant-current power supply, a timer, a steady-flow water tank, an aeration pump, a gravity-driven ceramic membrane water treatment device, a ceramic ultrafiltration membrane, an overflow pipe, a flow meter, K1 filler, an aeration strip and a valve.The electric flocculation process can effectively remove phosphorus in sewage, and the K1 filler serves as a main carrier of a biological membrane, intercepts most of the flocculation produced by the electric flocculation and inorganic macromolecules, effectively reduces the membrane pollution problem, isolates the water in the membrane pool from oxygen, provides an anaerobic environment for the biological membrane, and thus performs denitrification and nitrogen removal.Compared with a traditional sewage advanced treatment process, the device better retains the flux, greatly prolongs the service life of the membrane, slows down the membrane pollution, reduces the cost and water cost, can long-term output domestic / city miscellaneous water, and relieves the water shortage problem.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of advanced wastewater treatment, in particular to an electric flocculation coupled gravity-driven water purification device and a use method thereof. BACKGROUND

[0002] Advanced wastewater treatment refers to a further water treatment process for treating urban wastewater or industrial wastewater after primary and secondary treatment, so as to achieve a certain water reuse standard and make the wastewater be reused as water resources for production or life. According to the raw water quality of the wastewater and the water quality requirement after treatment, a tertiary treatment or multistage treatment process can be further used. The common method for removing trace COD and BOD organic pollutants, SS, high-concentration nutrients such as nitrogen and phosphorus, and salts in water is physical and chemical methods such as flocculation sedimentation, sand filtration, activated carbon method, ozone oxidation method, membrane separation method, ion exchange method, electrolytic treatment, wet oxidation method, evaporation and concentration method, and biological denitrification and dephosphorization method. The membrane separation method is a new fluid separation unit operation technology represented by a high polymer separation membrane. The biggest feature is that there is no phase change in the separation process, and a very high separation effect can be obtained by using only a certain pressure as a driving force, which is a very energy-saving separation technology. The future research focus is to develop, manufacture high-strength, long-life, anti-pollution and high-flux membrane materials, and to focus on solving key problems such as membrane pollution, concentration polarization and cleaning. The ceramic ultrafiltration membrane has the characteristics of high filtration precision, low energy consumption, strong anti-pollution performance and long service life. However, the existing ceramic membrane bioreactor mostly does not add fillers into the membrane pool, and there is no general method to deal with the membrane pollution problem after long-term use. Some conventional methods cannot well solve the problem of flux decline after membrane pollution. Therefore, the personnel in the field urgently need to find a new technical solution to solve the above problems. SUMMARY

[0003] In order to overcome the problems of removing phosphorus and ammonia nitrogen in the advanced wastewater treatment in the prior art, the present application provides an electric flocculation coupled gravity-driven water purification device and a use method thereof.

[0004] According to a first aspect of the present application, an electric flocculation coupled gravity-driven water purification device is provided: including a raw water storage pool 1, a raw water outlet pump 2, a raw water outlet valve 3, an outlet flow meter 4, a constant voltage power supply 5, an electric flocculation pool 6, a steady flow pool 7, a steady flow pool outlet valve 8, a floating ball valve 9, K1 filler 10, overflow pipe 11, aeration pump 12, air flow meter 13, air pipe valve 14, gravity-driven ceramic membrane water treatment device outlet valve 15, aeration strip 16, gravity-driven ceramic membrane water treatment device 17, ceramic ultrafiltration membrane 18, and clean water collecting tank 19.

[0005] The raw water storage tank 1 is connected with the electric flocculation tank 6 through the raw water outlet valve 3 and the raw water outlet pump 2, the electric flocculation tank 6 is connected with the steady flow water tank 7 through the water outlet 603, the steady flow water tank 7 is connected with the float ball valve 9 through the steady flow water tank outlet valve 8 and the gravity-driven ceramic membrane water treatment device 17, the water outlet of the gravity-driven ceramic membrane water treatment device 17 is connected with the clean water collecting tank 19 through the outlet valve 15, and excessive raw water is discharged through the overflow port 11.

[0006] Optionally, the electric flocculation tank 6 further comprises a raw water inlet 601, a water outlet 603, a flow guide port 604 and an electrode sheet 602.

[0007] Optionally, the gravity-driven ceramic membrane water treatment device 17 comprises a water inlet float ball valve 1701, K1 filler 1702, an aeration strip 1704, a gravity-driven water treatment device box 1707, a ceramic ultrafiltration membrane 1705, a water outlet 1703 and an overflow water outlet 1706.

[0008] Optionally, the ceramic ultrafiltration membrane 8 is internally hollow, and the hollow cavity is connected with the membrane assembly water outlet pipe, and the filtered water flows out through the membrane assembly water outlet pipe at the water outlet 1703.

[0009] Optionally, the pool body is covered with K1 filler, the K1 filler is made of HDPE polyethylene material and is a circular block body with a diameter of 10 mm, and has the characteristics of high strength, high wear resistance, corrosion resistance, strong hydrophilicity and super large contact area. The existing MBR advanced treatment technology does not add filler into the membrane pool for combined cultivation of biological membrane, and the K1 filler is added into the membrane pool according to the filler to water volume ratio of 0.45 in the application, and the filler is suspended at the liquid surface position of the membrane pool through intermittent aeration of the aeration pump, so as to not only provide an attachment site for the growth of microorganisms, improve the bacterial abundance of the biological membrane and improve the water treatment effect, but also intercept the difficult-to-dissolve macromolecular particles, delay membrane pollution, improve membrane flux and prolong the service life of the ceramic membrane.

[0010] Optionally, the raw water outlet pump 2, the constant voltage power supply 5 and the aeration pump 12 are respectively electrically connected with the timer.

[0011] Optionally, the raw water is raised to the electric flocculation tank 5 through the water inlet pump 2, and then flows into the steady flow water tank 7 after the electric flocculation treatment, flows into the gravity-driven ceramic membrane water treatment device 17 through the gravity effect, and then the ammonia nitrogen and the difficult-to-dissolve substances in the raw water are removed through the biological membrane effect of the filler, the water flow in the device flows into the hollow cavity through the surfaces on both sides of the ceramic ultrafiltration membrane 18 under the gravity effect, the water treatment effect is further improved, and then the water flows into the clean water collecting tank 19 through the water outlet pipe.

[0012] According to the second aspect of the disclosed embodiment, a use method of the electric flocculation coupled gravity-driven water purification device is provided, which is applied to the electric flocculation coupled gravity-driven water purification device of the first aspect of the disclosed embodiment, and the method comprises the following steps:

[0013] The raw water is lifted into the electric flocculation tank by the water pump for electric flocculation and phosphorus removal;

[0014] The water treated by the electric flocculation is flowed into the gravity-driven ceramic membrane water treatment device by gravity potential;

[0015] The ammonia nitrogen in the raw water is removed by the biological membrane with the filler according to the biological action, so that the water flow in the device enters into the cavities on both sides of the ceramic ultrafiltration membrane by gravity;

[0016] The insoluble substances in the water are filtered out by the ceramic membrane ultrafiltration;

[0017] The filtered water is discharged to the clean water collecting tank.

[0018] Compared with the prior art, the present application has the following effects:

[0019] The present application utilizes the gravity-driven ceramic ultrafiltration membrane to deeply treat the sewage, the Fe 3+ The present application has a good removal effect on the phosphorus in the raw water, and compared with the traditional membrane filtration, the K1 filler layer with a filler to water volume ratio of 0.45 is added as the main carrier of the biological membrane, the filler layer covers the pool body to the water level 5 cm below the water surface, can better intercept the flocculation and inorganic macromolecular substances generated by the electric flocculation, retain the flux, and greatly prolong the service life of the membrane, obviously slow down the membrane pollution, greatly reduce the maintenance cost and water cost. The intermittent aeration of the aeration pump makes the filler suspended at the membrane pool liquid surface position, the K1 filler layer can provide an attachment site for biological growth, the formed biological membrane layer is the main biological component for purifying water quality, effectively performs the nitrification reaction to convert the ammonia nitrogen into nitrate nitrogen. Since the filler layer covers the membrane pool water surface, the water in the membrane pool is effectively isolated from the air to form a natural isolation cover. When the water in the membrane pool is dissolved oxygen to a relatively low level, the biological membrane performs the denitrification reaction to perform the denitrification treatment. The whole device does not need to additionally set an anaerobic tank, reduces the construction cost, and improves the operation efficiency. During the operation of the device, the flow meter and the timer are combined, the water pump speed and the aeration amount can be changed according to the water inlet or outlet demand, the operation cost is low, the operation and management are convenient and simple, and the automatic management can be realized. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a schematic diagram of an electric flocculation coupled gravity-driven ceramic membrane device system for deeply treating sewage

[0021] Figure 2is an electric flocculation tank structure schematic diagram

[0022] Figure 3 is a gravity-driven ceramic membrane water treatment device structure schematic diagram DETAILED DESCRIPTION

[0023] The drawings are only used for illustrative purposes and cannot be understood as a limitation on the present application; in order to better illustrate the embodiments, some components in the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted. The positional relationship described in the drawings is only used for illustrative purposes and cannot be understood as a limitation on the present application.

[0024] The technical solution of the present application is:

[0025] An electric flocculation coupled gravity-driven ceramic membrane device for advanced treatment of sewage, comprising a raw water storage tank, a water outlet pump, a flow meter, an electric flocculation tank, a constant voltage power supply, a timer, a steady flow water tank, an overflow pipe, an aeration pump, a gravity-driven ceramic membrane filter water treatment device, a ceramic ultrafiltration membrane, K1 filler, an aeration strip, a water outlet valve, and a clean water collection tank.

[0026] The process of treating advanced treatment of sewage by the present application is as follows:

[0027] The collected advanced treatment of sewage is stored in the raw water storage tank, and under the push of the raw water outlet pump, the raw water flows from the raw water tank into the electric flocculation tank, and after electrolysis, the flocculation produced by electric flocculation and the raw water flow into the steady flow water tank, and under the action of gravity, the raw water and flocculation in the steady flow water tank enter the gravity-driven ceramic membrane filter device. The raw water entering the filter device is first intercepted by the K1 filler, and under the action of the K1 filler biofilm, the ammonia nitrogen in the raw water is removed, and then passes through the ceramic membrane. The ceramic membrane can intercept suspended substances that cannot be treated by the biofilm, and the water quality is further improved. Then the effluent flows into the clean water collection tank from the effluent pipe. The treated water can be used as domestic miscellaneous water and is transported to various water using appliances for daily use. The role of the aeration pump is to aerate at regular intervals to improve the suitable dissolved oxygen concentration of the biofilm in the gravity-driven ceramic membrane filter device, so that it can complete nitrification and denitrification and purify the ammonia nitrogen in the raw water.

[0028] The process of the electric flocculation coupled gravity-driven ceramic membrane device for membrane filtration treatment of advanced treatment of sewage is as follows:

[0029] The raw water enters the gravity-driven ceramic membrane filter device under the action of gravity, the K1 filler layer intercepts most of the flocculation and serves as the main carrier of the biofilm, effectively alleviating the problem of membrane pollution. The water treated by the biofilm enters the space in the ceramic ultrafiltration membrane under the action of gravity, and flows to the clean water collection tank through the water outlet pipe for daily use.

[0030] Example 1:

[0031] like Figure 1 As shown, an electrocoagulation coupled gravity-driven ceramic membrane device for deep wastewater treatment includes a raw water storage tank 1, a raw water outlet pump 2, a raw water outlet valve 3, an outlet flow meter 4, a constant voltage power supply 5, an electrocoagulation tank 6, a flow stabilization tank 7, a flow stabilization tank outlet valve 8, a float valve 9, K1 packing material 10, an overflow pipe 11, an aeration pump 12, an air flow meter 13, an air pipe valve 14, a gravity-driven ceramic membrane water treatment device outlet valve 15, an aeration strip 16, a gravity-driven ceramic membrane water treatment device 17, a ceramic ultrafiltration membrane 18, and a purified water collection tank 19.

[0032] For example, the collected deep-treated wastewater is stored in the raw water storage tank 1. Driven by the raw water effluent pump 2, the raw water flows from the raw water storage tank 1 into the electrocoagulation tank 6. After electrolysis in the electrocoagulation tank, it flows into the stabilization tank 7. Under the pressure of gravity, it enters the gravity-driven ceramic membrane water treatment device 17. Under the pressure provided by gravity, it is filtered through the membrane and flows into the clean water collection tank 19 through the effluent pipe.

[0033] The raw water storage tank 1 has a raw water outlet valve 3 at its outlet, the steady flow tank 7 has a steady flow outlet valve 8 at its outlet, and the purified water collection tank 19 has an outlet valve 15 at its inlet, all used to control the opening and closing of the pipeline flow. Additionally, the raw water outlet pump 2 and the aeration pump 12 can be controlled by timers.

[0034] The process of treating advanced wastewater according to this invention is as follows:

[0035] The collected, deeply treated wastewater is stored in the raw water storage tank 1. The raw water outlet valve 3 is opened, and driven by the raw water inlet pump 2, the raw water flows from the raw water storage tank 1 into the electrocoagulation tank 5. The electrocoagulation tank begins electrolyzing iron sheets. After the electrocoagulation tank 6 reaches a certain water level, the raw water and flocs overflow into the steady flow tank 7. Under gravity, it enters the steady flow tank outlet valve 8, passes through the float valve 9 which controls the water level, and flows into the gravity-driven ceramic membrane water treatment device 17. The raw water first undergoes interception by the packing material and the action of the biofilm, removing ammonia nitrogen and insoluble substances. In the device, the water flows under gravity through both sides of the ceramic ultrafiltration membrane 18 into the cavity, and then flows into the purified water collection tank 19 through the outlet pipe. The treated water can be supplied to various water-using appliances for daily use. Insoluble substances include: proteins, polysaccharides and other colloidal impurities, rust, suspended solids, silt, and large molecular organic matter.

[0036] See Figure 2 In this embodiment, the electrocoagulation tank 6 includes a raw water inlet 601, a water outlet 603, a flow guide 604, and an electrode sheet (usually an iron sheet) 602.

[0037] The process of treating raw water by the electric flocculation tank 6 and the gravity-driven ceramic membrane water treatment device 17 is as follows: after the raw water enters the electric flocculation tank 6 through the raw water inlet 601, the electric flocculation tank starts to generate flocculation bodies by electrolyzing the electrode sheet 602, the raw water and the flocculation bodies are subjected to hydraulic mixing through the flow guide opening 604 of the electric flocculation tank, the phosphorus in the raw water is combined with the flocculation bodies to generate metal phosphate to be removed, and part of the flocculation bodies flow into the steady flow tank 7 through the pipe from the water outlet 603 of the electric flocculation tank 6, and then the raw water and the flocculation bodies enter the gravity-driven ceramic membrane water treatment device 17 through gravity, when entering the gravity-driven ceramic membrane water treatment device 17, the flocculation bodies and inorganic macromolecular substances are first intercepted by the K1 filler 10, then the water flow passes through the filler biofilm for denitrification treatment, after passing through the biofilm, the water flow is filtered out through the ceramic ultrafiltration membrane 18 under the action of gravity, and the water quality is further improved, and finally flows into the clean water collecting tank 19 for collection.

[0038] Referring to Figure 3 In the embodiment, the gravity-driven ceramic membrane water treatment device 17 includes a water inlet floating ball valve 1701, a K1 filler 1702, a gravity-driven ceramic membrane water treatment device box 1707, a ceramic ultrafiltration membrane 1705, a water outlet 1703, and an overflow water outlet 1706.

[0039] The process of treating raw water by the gravity-driven ceramic membrane water treatment device 17 is as follows: the raw water flows into the gravity-driven ceramic membrane water treatment device 17 from the floating ball valve water inlet 1701 at the top of the gravity-driven ceramic membrane water treatment device 17 under the action of gravity, the water flow flows downward, first passes through the K1 filler 1702, the flocculation bodies generated by electric flocculation and inorganic macromolecular substances in the raw water are intercepted by the filler, the raw water is subjected to denitrification treatment after passing through the biofilm, and then the water quality is further improved after passing through the ceramic ultrafiltration membrane 1705, and the water enters the cavity in the ceramic ultrafiltration membrane 1705 under the action of gravity and flows to the clean water collecting tank 19 through the water outlet 1703 for daily use.

[0040] In the electric flocculation tank 6, the Fe 3+The phosphorus in the raw water is combined to form insoluble metal phosphate to be removed, and the gravity-driven ceramic membrane water treatment device 17 is connected to form a water path by gravity, and the generated flocculation forms a biological membrane on the K1 filler 10, which can effectively improve the removal effect of total phosphorus and ammonia nitrogen in the sewage, and improve the water quality of the effluent; the gravity-driven ceramic membrane water treatment device 17 is used to treat the sewage, and the K1 filler 10 can intercept most of the flocculation and inorganic macromolecular substances, so that the flux of the ceramic ultrafiltration membrane 18 can be better preserved, the service life of the membrane is greatly prolonged, the membrane pollution is obviously reduced, and the maintenance cost and water cost are greatly reduced; the opening and closing of the raw water outlet pump 2, the constant voltage power supply 5 and the aeration pump 12 are controlled by the timer, so that the water inlet and outlet in the system are more coordinated, and automatic operation and management can be realized.

[0041] For example, in the experimental process, the ammonia nitrogen of the raw water is 5.8-6.2 mg / L, the total phosphorus is 0.9-1.1 mg / L, the NTU is 12-15, and the aeration amount in the gravity-driven ceramic membrane device pool is 2 L / min, the aeration time is 15 min, the dissolved oxygen in the membrane pool reaches 2.5-3.0 mg / L, which is suitable for the nitration reaction. After the device is used for electric flocculation and denitrification deep treatment, the effluent water quality is ammonia nitrogen 0.02-0.05 mg / L, total phosphorus 0.005-0.008 mg / L, and NTU 0.01-0.05, which meets the water quality indexes of 'Urban Sewage Reuse Urban Miscellaneous Water Quality' (GB / T 18920-2002) and 'Urban Sewage Reuse Landscape Environment Water Quality' (GB / T 18921-2002). The treated effluent can be reused to alleviate the water problem of the building, and has practical significance.

[0042] Obviously, the above embodiments of the present application are only examples for clearly illustrating the present application, and are not a limitation on the embodiments of the present application. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, all the embodiments are not enumerated. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An electrocoagulation coupled gravity driven water purification device, characterized in that: The application relates to a gravity-driven ceramic membrane water treatment device, which comprises an original water storage pool (1), an original water outlet pump (2), an original water outlet valve (3), an outlet flowmeter (4), a constant-voltage power supply (5), an electric flocculation pool (6), a steady flow water tank (7), a steady flow water tank outlet valve (8), a float ball valve (9), K1 filler (10), an overflow pipe (11), an aeration pump (12), an air flowmeter (13), an air pipe valve (14), a gravity-driven ceramic membrane water treatment device outlet valve (15), an aeration strip (16), a gravity-driven ceramic membrane water treatment device (17), a ceramic ultrafiltration membrane (18) and a clean water collecting tank (19). The original water storage pool (1) is connected with the electric flocculation pool (6) through the original water outlet valve (3) and the original water outlet pump (2), the electric flocculation pool (6) is connected with the steady flow water tank (7) through a water outlet (603), the steady flow water tank (7) is connected with the float ball valve (9) and the gravity-driven ceramic membrane water treatment device (17) through a steady flow water tank outlet valve (8), the water outlet of the gravity-driven ceramic membrane water treatment device (17) is connected with the clean water collecting tank (19) through a water outlet valve (15), and excessive original water is discharged through the overflow pipe (11). The gravity-driven ceramic membrane water treatment device (17) comprises an inlet float ball valve (1701), K1 filler (10), an aeration strip (16), a gravity-driven water treatment device box (1707), a ceramic ultrafiltration membrane (18), a water outlet (1703) and an overflow water outlet (1706). The K1 filler is prepared from a circular block-shaped body with a diameter of 10mm and is made of HDPE polyethylene material, the ratio between the K1 filler and water is 0.45:1, the filler layer covers the pool body to a water level of 5cm below the water surface, and the filler is suspended at the membrane pool liquid surface position through intermittent aeration of the aeration pump.

2. The device according to claim 1, wherein The electric flocculation pool (6) further comprises an original water inlet (601), a water outlet (603), a flow guide opening (604) and electrode sheets (602).

3. The device according to claim 1, wherein The ceramic ultrafiltration membrane (18) is internally hollow, the hollow cavity is connected with a membrane assembly water outlet pipe, and filtered water flows out through the membrane assembly water outlet pipe at the water outlet (1703).

4. The device according to claim 1, wherein The original water outlet pump (2), the constant-voltage power supply (5) and the aeration pump (12) are respectively electrically connected with a timer.

5. The device according to claim 1, wherein Original water is lifted to the electric flocculation pool (6) through the inlet pump (2), and then flows into the steady flow water tank (7) after electric flocculation treatment, flows into the gravity-driven ceramic membrane water treatment device (17) through gravity, and then the original water is subjected to biological membrane action of the filler, ammonia nitrogen and insoluble substances in the original water are removed, water flow in the device flows into the hollow cavity through the two sides of the ceramic ultrafiltration membrane (18) under the action of gravity, the water quality treatment effect is further improved, and then the water flows into the clean water collecting tank (19) through the water outlet pipe.

6. A method of using an electrocoagulation coupled gravity-driven water purification device, characterized in that, The method is applied to the electric flocculation coupled gravity-driven water purification device in any one of claims 1-5, and the method comprises the following steps: Lifting original water to the electric flocculation pool (6) through a water pump for electric flocculation and phosphorus removal; Making the water treated through electric flocculation flow into the gravity-driven ceramic membrane water treatment device through gravity potential energy; The biological membrane filled with fillers removes ammonia nitrogen in raw water according to biological action, so that water flow in the device enters into cavities on both sides of the ceramic ultrafiltration membrane (18) through gravity action; The ceramic membrane ultrafiltration filters out insoluble substances in water; The filtered water is discharged to a clean water collecting tank.

Images