WO2021109329A1

WO2021109329A1 - Micro-water quantity backwashing variable-speed upward-flow lightweight-filtering-material filter, and method thereof

Info

Publication number: WO2021109329A1
Application number: PCT/CN2020/072602
Authority: WO
Inventors: 夏文香; 石志慧; 李金成; 宋双; 越楚遥; 赵宝秀; 刘杰
Original assignee: 青岛理工大学
Priority date: 2019-12-05
Filing date: 2020-01-17
Publication date: 2021-06-10
Also published as: CN110917679A; JP2022515583A; JP7145544B2; CN110917679B

Abstract

Provided are a micro-water quantity backwashing variable-speed upward-flow lightweight-filtering-material filter, and a running operation method thereof. The filter comprises a reactor (1), a water intaking and distributing system, a gas backwashing system, a micro-water backwashing spraying system, a water collecting system and a water discharging/sludge discharging system; the interior of the reactor (1) is divided into a water intaking/sludge discharging area (2), a backwashing stripping area (3), a variable-speed filtering area (4), a compaction filtering area (5) and a water collecting area (6); an anti-floating filtering plate (12) is arranged on the upper part of the compaction filtering area (5), the anti-floating filtering plate (12) is provided with a filter head (13), a cover plate (14) is arranged directly above the anti-floating filtering plate (12), a flow guide plate is arranged at the periphery of the cover plate (14), and an exhaust valve (9) is arranged on the cover plate (14); the water intaking/sludge discharging area (2) is located at the bottom of the reactor (1), the backwashing stripping area (3) is located at the upper part of the water intaking area (2), the backwashing stripping area (3) is of a cylindrical shape, and the volume of the backwashing stripping area (3) is equal to the sum of the volume of the variable-speed filtering area (4) and the volume of the compaction filtering area (5); the variable-speed filtering area (4) is located at the upper part of the backwashing stripping area (3), and the cross-sectional area of the area gradually decreases from bottom to top and is in the shape of a truncated cone; and the compaction filtering area (5) is located at the upper part of the variable-speed filtering area (4) and is cylindrical, and the cross-sectional area of the compaction filtering area is the same as the cross-sectional area of the upper part of the variable-speed filtering area (4).

Description

Micro-water backwash variable-speed upward-flow lightweight filter material filter and method thereof

Technical field

The invention belongs to the technical field of water treatment, and is suitable for small and medium-sized water supply treatment, advanced sewage treatment and industrial reuse water treatment, and relates to an upward variable-speed flow light suspension filter material filter. In particular, it is a water-saving type micro-water backwashing variable-speed upward-flow lightweight filter material filter and its method.

Background technique

Filter layer filtration technology is an important process unit in the water and wastewater treatment process. Generally, a certain thickness of filter layer is constructed by selecting granular filter materials of different materials, and the gap between the particles is used to form a filter channel to intercept suspended impurities in the water. At present, the commonly used filters mainly include ordinary pressure filters, valveless filters, fiber filter media filter tanks and other filters. Ordinary fast filter is the most traditional filter. Generally, quartz sand is used as the filter material, and the filtering method adopts downward flow. Because of the pollutants trapped in the filtration process, it needs to be backwashed with water to peel off the filter layer and recover. The filter layer has the ability to intercept dirt, so backwashing needs to use high-speed water flow to reverse the filter layer. On the one hand, it will consume a lot of purified water, and on the other hand, it will also cause an increase in energy consumption. The valveless filter adopts the hydraulic principle to form the characteristics of automatic backwashing, but the backwashing water volume of the valveless filter is also high, and the backwashing is not thorough. In the research of sewage filtration, fiber filter media filter is also a common filter form. Usually the filter material can be fiber balls and fiber bundles. This form of filter has the characteristics of high filtration speed and not easy to foul, but There is a problem that the water consumption of recoil is large, and the filter material should be compacted.

In response to the above problems, lightweight suspension filter media has gradually attracted attention in China in recent years. As a new type of filter material, expandable polystyrene particles (EPS) lightweight suspension filter media have high mechanical strength, strong decontamination ability, and stable chemical properties. , The specific gravity is smaller than that of water, the filtering method is simple, and the application range is wide. Compared with the traditional quartz sand filter, the lightweight suspension filter has a greater economic advantage, that is, the influent buffer section can be used for precipitation. The supporting layer is needed, the structure is simple, and the infrastructure cost is reduced. The French Deliman Company has developed a new type of upward flow suspension filter by using lightweight filter media, which has a unique backwashing method. However, because its form is only the reversal of the conventional filter, and a large-area anti-floating filter plate and filter head need to be installed, the complexity of the structure is increased. The recoil water saving and filtration rate of the filter are also not much different from the traditional filtration rate. Therefore, the current upflow filter has been used to a certain extent, but it has not been effectively promoted.

At present, energy saving and consumption reduction is a development direction of water treatment. Traditional filtration equipment usually needs to consume a large amount of backwash water. On the one hand, it increases water volume and energy consumption, and on the other hand, it also increases the difficulty of backwashing wastewater treatment. In the backflushing process, the water consumption can be reduced by increasing the air flushing method, but the single air flushing of the conventional filter cannot flush the stripped pollutants out of the filter layer. It must be matched with the water flushing, so it cannot fundamentally solve the energy consumption and water consumption. The problem. The development of upflow lightweight filter media can provide a solution to the above problems.

Summary of the invention

The purpose of the present invention is to overcome the shortcomings of the existing upflow filter technology, by creatively changing the shape and composition of the filter, to optimize the filter structure and reduce the filtering resistance, and at the same time use the pressure change of the variable flow to form a self-compression function. To achieve the purpose of improving filtration accuracy, the backwashing process cleverly uses the gravity of the trapped dirt, and relies on air washing to naturally separate the debris from the filter material, realizes a micro-water backwash, and greatly reduces the water consumption and energy consumption of the backwash. As a result, a new type of micro-water recoil variable-speed upward-flow lightweight suspended filter material filter and its method are established.

In order to achieve the above objectives, the present invention adopts the following technical solutions:

A micro-water backflush variable-speed upward-flow lightweight filter material filter, including: reactor 1, water inlet water distribution system, gas backwash system, micro-water backwash spray system, water collection system, drainage/sludge discharge system ；

The inside of reactor 1 is divided into water inlet/sludge discharge area 2, backwash stripping area 3, variable speed filter area 4, compaction filter area 5, water collection area 6; an anti-floating filter plate is installed on the upper part of compaction filter area 5 12. A filter head 13 is installed on the anti-floating filter plate 12, a cover plate 14 is installed directly above the anti-floating filter plate 12, a deflector is provided around the cover plate 14, and an exhaust valve 9 is provided on the cover plate 14;

The water inlet/sludge discharge zone 2 is located at the bottom of the reactor 1, the backwash stripping zone 3 is located on the upper part of the water inlet zone 2, and the backwash stripping zone 3 is cylindrical. The volume of the backwash stripping zone 3 and the variable speed filter zone 4 and pressure The total volume of the actual filter zone 5 is equal, and the dirt in the water to be treated will first be intercepted by the filter layer of the variable-speed filter zone;

The variable-speed filter zone 4 is located at the upper part of the backwash stripping zone 3. The cross-sectional area of this zone gradually decreases from bottom to top, and is in the shape of a truncated cone. Because the water flow rate is constant, the cross-sectional area decreases, and the filter layer in this area is affected by the The upward filtration rate pressure also gradually increases;

The compaction filter zone 5 is located in the upper part of the variable-speed filter zone 4, which is cylindrical, and its cross-sectional area is the same as that of the upper part of the variable-speed filter zone 4. The initial water flow velocity of the compacted filter zone 5 is that of the variable-speed filter zone 4. The maximum water flow rate, the filter layer of which is subjected to the greatest pressure, and the filter layer is the densest.

In the filter, the raw water to be treated enters the bottom of the reactor 1 through the water inlet/sludge discharge zone 2, and then passes through the backwash stripping zone 3, the variable speed filter zone 4, and the compaction filter zone 5 for interception and filtration. The water passes through the filter head and meets the cover plate 14, passes through the deflector of the cover plate 14 and flows into the clear water tank 15, and then enters the catchment area 6 through the overflow weir 16, and finally the water is collected into the clear water tank 38 by the outlet pipe 17.

In the filter, the filter material filled in the reactor is expandable polystyrene particles (EPS) 36, and the particle size specification is 0.5-1 mm.

The filter, the inlet water distribution system includes: a raw water tank 37, a water pump 18, a raw water inlet pipe 10, an inlet valve 25 and a reflector 11; the raw water inlet pipe 10 is equipped with an inlet valve 25, and the reflector 11 is located in the inlet pipe The raw water tank 37 is connected to the inlet of the water pump 18, the outlet of the pump 18 is connected to the raw water inlet pipe 10 and the inlet valve 25, and the reflector 11 is located directly below the raw water inlet pipe 10. The water to be treated is pressurized by a water pump and transported into the water inlet/sludge discharge area 2 at the bottom of the reactor 1 through the raw water inlet pipe, and the inlet water is uniformly distributed through the reflector 11.

The filter, the water collection system includes a clean water outlet pipe 17 and a clean water tank 38. One end of the clean water outlet pipe 17 is connected to the water collection area 6, and the other end is connected to the clean water tank 38. There is a gap between the water collection area and the clean water tank 38. , The clear water automatically flows into the clear water tank by using the drop.

The filter, the micro-water backwash spray system includes a clean water pump 19, a micro-water backwash main pipe 23, a micro-water backwash valve 30 and a valve 31, a micro-water backwash spray branch 8 and a filter aid spray head 24 , Liquid level sensor 35 and liquid level detection instrument 34; clean water pump 19 is connected to clean water tank 38, clean water pump 19 is connected to micro water backwash spray branch pipe through micro water recoil main pipe 23, micro water recoil valve 30, valve 31 8. Micro-water recoil spray branch pipes 8 are circumferentially arranged outside the compaction filter zone 5 and the variable-speed filter zone 4. Each micro-water recoil spray branch pipe 8 is provided with a plurality of filter aid washing nozzles 24 to pass the water Into the compaction filter zone 5 and the variable speed filter zone 4; the liquid level sensor 35 is set on the top of the backwash stripping zone 3, and is connected with the liquid level detection instrument 34 through the data line, and is used for the basis of the backwashing process. The water level sensing result of the liquid level sensor 35 controls the water level at the top of the backwash stripping zone 3.

The filter and air backwash system includes an air compressor 20, a backwash air pipe 22, a backwash air pipe nozzle 7, a backwash air valve 28 and a check valve 26, and a backwash air release valve 9. The drain pipe 21 of the reactor 1 is equipped with a drain/sludge valve 27; the backwash gas pipe 22 in the reactor 1 is provided with evenly distributed backwash gas pipe nozzles 7 on the pipe section at the bottom of the backwash stripping zone 3. A backwash gas valve 28 and a check valve 26 to prevent water pouring are installed on the flushing gas pipe 22; an exhaust valve 9 is provided on the top cover of the reactor 1;

The filter, the drainage/sludge system includes a drainage/sludge pipe 21, a drainage/sludge valve 27, a drainage/sludge pipe 21 is arranged at the bottom of the water/sludge area 2, and a drainage/sludge pipe 21 A drain/sludge valve 27 is provided on it.

In the filter, the operation process of the micro-water backflush, variable-speed upward-flow lightweight filter material filter is divided into: (1) filtration process; (2) backwash process; (3) light filter material layer reset process ; Three processes are carried out in cycles;

(1) Filtration process: Close the drain/sludge valve 27, the backwash intake valve 28 and the connecting valve 29, open the water inlet valve 25 and the exhaust valve 9, start the water inlet pump 18, and the raw water tank 37 will be placed in the raw water tank 37 by the water pump 18 The treated water is transported into the reactor 1 through the water inlet pipe 10, and the water to be treated flows from the water inlet pipe 10 through the reflector 11 for uniform water distribution. The filtered water flows upward through the backwash stripping zone 3, the variable speed filter zone 4, and the compaction filter zone 5 in turn. Finally, the water flow filter head enters the clean water area. When the rising water flow meets the cover plate 14, the effluent is first discharged from the exhaust pipe. At this time, the exhaust valve 9 is closed, and the water flows into the clean water tank 15 through the deflector, and then passes through the overflow. The weir 16 flows into the water collection area 6 and finally enters the clean water tank 38 through the outlet pipe 17.

(2) Backwashing process: close the water inlet valve 25, open the drain/sludge valve 27, the water level in the reactor 1 gradually drops as the water is discharged from the drain/sludge valve 27, and the filter material also drops. Open the communication valve 29, the micro-water inlet regulating valve 30 and the valve 31 at the time, start the micro-water spray pump 19, and use the spray effect of the filter aid nozzle 24 to promote the dispersion of the filter material in the compacted filter zone 5 downward. Finally, the liquid level sensor 35 and the liquid level detecting instrument 34 are used to control the water level at the top of the backwash stripping zone 3. At this time, close the communication valve 29, the micro water inlet regulating valve 30 and the valve 31, close the micro water spray pump 19, open the air backwash valve 28, the exhaust valve 9, start the air pump 20, and the gas is pressurized by the air compressor 20 After that, enter the reactor from the gas pipe 20, the gas volume regulating valve 28, and the check valve 26, and then blow out through the backwashing gas pipe nozzle 7 to stir the light filter material for 5-10 minutes, so that the filter material is trapped by the filter layer. The dirt is stripped from the filter material by the shearing action of the gas and its own gravity, and then the air compressor 20 and the valve 28 are closed, and the stripped impurities are collected in the drainage/sludge zone 2 by the sedimentation effect, and the sedimentation time is 20-30min. Then, the drain/sludge valve 27 is opened, and the sludge is discharged with the water flow through the sludge pipe 21 to complete the backwashing process.

(3) The reset process of the light filter material layer: After the backwashing is completed and the mud is discharged, the light filter material layer needs to be reset before the next filtration process. First, close the drain/sludge valve 27 and the backwash air valve 28, open the micro-water spray inlet valve 30 and valve 31, open the connecting valve 29 and the exhaust valve 9, start the micro-water spray pump 19, and start the micro-water spray pump 19 Under the action of the washing water of the shower pump 19, the water flow is sprayed from the filter aid nozzle 24 into the reactor 1. The water level in the reactor 1 gradually rises, and the expandable polystyrene particle (EPS) filter material 36 is because of the specific gravity ratio. The water is small, and the automatic reset is realized under the support of this rising water flow. At the same time, the micro-water spray assists in the adjustment of the distribution of the lightweight filter material during the ascending process, and the effect of the rising filter material on the anti-floating filter plate and the water flow upward Under the pressure, the filter layer is gradually compacted. At this time, close the micro-water spray inlet valve 30 and valve 31, continue to keep the micro-water spray pump 19 running for 5-10 minutes, then close the micro-water spray pump 19 and the connecting valve 29 , Complete the reset process of the filter layer.

Compared with the existing filter, the present invention has the following advantages:

The first is to adopt a variable filter cross-section design to form a filter state where the filter speed is changed from slow to fast, and the pressure is changed from low to high. It can not only achieve the purpose of automatic compression of the filter layer by hydraulic pressure during filtration, but also solve the previous light filter. The material filter layer itself cannot be compacted and the pores are loose;

The second is to use the gravity of the trapped sludge during backwashing to separate it from the filter material through air flushing and stirring, and to separate it from the light filter material by gravity sedimentation, eliminating the need for backwashing water, saving water and reducing consumption;

Thirdly, it is the first time to set up the filter material washing spray hole in the lightweight filter material area, which can help the compacted filter material move down at the beginning of backwashing, or further rinse the filter material with a small amount of water when the filter material is reset after backwashing. Residual impurities improve the cleaning effect of the filter layer;

The fourth is that the upward flow relies on hydraulic compaction to automatically form a large to small distribution of pores, which conforms to the grading principle of the filtration process, so the filtration resistance is small and energy saving.

Description of the drawings

Figure 1 Working principle diagram when filtering;

Figure 2 Working principle diagram during backwashing;

Detailed ways

The present invention will be described in detail below in conjunction with specific embodiments.

The micro-water backflushing variable-speed upward-flow lightweight filter material of this embodiment includes: reactor 1, inlet water distribution system, gas backwashing system, micro-water backwashing spray system, water collection system, drainage/sludge removal system.

Reactor 1 is made of stainless steel. The interior of reactor 1 is divided into water inlet/sludge discharge zone 2, backwash stripping zone 3, variable-speed filtration zone 4, compaction filtration zone 5, and water collection zone 6, of which variable-speed filtration zone 4 and pressure The filter material filled in the solid filter zone 5 is expandable polystyrene particles (EPS) 36 with a particle size of 0.5 to 1 mm; an anti-floating filter plate 12 and an anti-floating filter plate 12 are installed on the upper part of the compacted filter zone 5 A filter head 13 is installed on it, a cover plate 14 is installed directly above the anti-floating filter plate 12, a baffle plate is provided around the cover plate 14, and an exhaust valve 9 is provided on the cover plate 14;

The water inlet/sludge discharge zone 2 is located at the bottom of the reactor 1, the backwash stripping zone 3 is located on the upper part of the water inlet zone 2, and the backwash stripping zone 3 is cylindrical, and the volume is the same as the volume of the variable speed filter zone 4 and the compaction filter zone 5. The sum is equal, the filter material filled in the filter area is expandable polystyrene particles (EPS), and the size of the filter material can be 0.5～1mm. The dirt in the water to be treated will be the first filter layer of the variable speed filter area. Intercept

The variable-speed filter zone 4 is located in the upper part of the backwash stripping zone 3. The cross-sectional area of this zone gradually decreases from bottom to top, and is in the shape of a truncated cone. Because of the constant water flow rate, the cross-sectional area decreases. According to the formula Q=A·υ. , The water flow rate gradually increases, and the upward pressure on the filter layer of the filter material in this area also gradually increases. The filter material filled in the variable-speed filter zone 4 is expandable polystyrene particles (EPS), and the particle size of the filter material can be selected from 0.5 to 1 mm.

The compaction filter zone 5 is located in the upper part of the variable-speed filter zone 4, which is cylindrical, and its cross-sectional area is the same as that of the upper part of the variable-speed filter zone 4. The initial water flow velocity of the compacted filter zone 5 is that of the variable-speed filter zone 4. The maximum water flow rate, the filter layer of which is the most stressed, the filter layer is the densest, the filled filter material is expandable polystyrene particles (EPS), the particle size of the filter material can be selected from 0.5 to 1mm.

The raw water to be treated enters the bottom of the reactor 1 through the water inlet/sludge discharging zone 2, and then passes through the backwash stripping zone 3, the variable speed filter zone 4, and the compaction filter zone 5 to intercept and filter. The filtered water will encounter To the cover plate 14, the flow deflector of the cover plate 14 flows into the clean water tank 15, and then enters the water collection area 6 through the overflow weir 16, and finally the water is collected into the clean water tank 38 by the outlet pipe 17.

The inlet water distribution system includes: a raw water tank 37, a water pump 18, a raw water inlet pipe 10, an inlet valve 25 and a reflector 11; the raw water inlet pipe 10 is equipped with an inlet valve 25, and the reflector 11 is located directly below the inlet of the water pipe. The water is distributed evenly; the raw water tank 37 is connected to the water inlet of the water pump 18, the outlet of the water pump 18 is connected to the raw water inlet pipe 10 and the water inlet valve 25, and the reflector 11 is located directly below the nozzle of the raw water inlet pipe 10. The water to be treated is pressurized by a water pump and transported into the water inlet/sludge discharge area 2 at the bottom of the reactor 1 through the raw water inlet pipe, and the inlet water is uniformly distributed through the reflector 11.

The water collection system includes a clean water outlet pipe 17 and a clean water tank 38. One end of the clean water outlet pipe 17 is connected to the water collection area 6, and the other end is connected to the clean water tank 38. There is a gap between the water collection area and the clean water tank 38, and the clean water automatically flows in by using the gap. Clean water tank.

The micro-water backwashing spray system includes a clean water pump 19, a micro-water back-flushing main pipe 23, a micro-water back-flushing valve 30 and valve 31, a micro-water back-flushing spray branch pipe 8 and a filter aid nozzle 24, and a liquid level sensor 35 And liquid level detection instrument 34; the clean water pump 19 is connected to the clean water tank 38, the clean water pump 19 is connected to the micro water backwash spray branch pipe 8 through the micro water backwash main pipe 23, the micro water backwash valve 30, and the valve 31. The spray branch pipe 8 is circumferentially arranged outside the compaction filter zone 5 and the variable-speed filter zone 4, and each micro-water backwash spray branch pipe 8 is provided with a plurality of filter aid washing nozzles 24 to pass water into the compaction filter zone 5 And the inside of the variable-speed filter zone 4; the liquid level sensor 35 is arranged on the top of the backwash stripping zone 3, and is connected with the liquid level detection instrument 34 through a data line, and is used to adjust the liquid level sensor 35 during the backwashing process. The water level sensing result controls the water level at the top of the backwash stripping zone 3;

The micro-water backwashing system has two functions. One is that after the filtration is completed, when entering the backwashing stage, the backwashing spray action is used to promote the compacted lightweight filter material 36 to disperse and fall back to the backwashing stripping zone 3. . Second, during the resetting process of the filter material after the backwashing is completed, the surface of the light filter material 36 is further washed by the backwash spray effect, and at the same time it plays a role in promoting the uniform arrangement of the filter material.

The air backwash system includes an air compressor 20, a backwash air pipe 22, a backwash air pipe nozzle 7, a backwash air valve 28 and a check valve 26, and a backwash air release valve 9. The drain pipe 21 of the reactor 1 is equipped with a drain/sludge valve 27; the backwash gas pipe 22 in the reactor 1 is provided with evenly distributed backwash gas pipe nozzles 7 on the pipe section at the bottom of the backwash stripping zone 3. A backwash gas valve 28 and a check valve 26 to prevent water pouring are installed on the flushing gas pipe 22; an exhaust valve 9 is provided on the top cover of the reactor 1;

The drainage/sludge system includes a drainage/sludge pipe 21, a drainage/sludge valve 27. The drainage/sludge pipe 21 is set at the bottom of the water/sludge area 2, and the drainage/sludge pipe 21 is equipped with a drainage/drainage pipe. Mud valve 27.

The specific operation process is:

The operation process of the micro-water backflush variable-speed upward-flow lightweight filter material filter is divided into: (1) filtration process; (2) backwash process; (3) light filter material layer reset process; the above three process cycles get on.

(2) Backwashing process: close the water inlet valve 25, open the drain/sludge valve 27, the water level in the reactor 1 gradually drops as the water is discharged from the drain/sludge valve 27, and the filter material also drops. Open the communication valve 29, the micro-water inlet regulating valve 30 and the valve 31 at the time, start the micro-water spray pump 19, and use the spray effect of the filter aid nozzle 24 to promote the dispersion of the filter material in the compacted filter zone 5 downward. Finally, the liquid level sensor 35 and the liquid level detecting instrument 34 are used to control the water level at the top of the backwash stripping zone 3. At this time, close the communication valve 29, the micro water inlet regulating valve 30 and the valve 31, close the micro water spray pump 19, open the air backwash valve 28, the exhaust valve 9, start the air pump 20, and the gas is pressurized by the air compressor 20 After that, enter the reactor from the gas pipe 20, the gas volume regulating valve 28, and the check valve 26, and then blow out through the backwashing gas pipe nozzle 7 to stir the light filter material for 5-10 minutes, so that the filter material is trapped by the filter layer. The dirt is stripped from the filter material by the shearing action of the gas and its own gravity, and then the air compressor 20 and the valve 28 are closed, and the stripped impurities are collected in the drainage/sludge zone 2 by the sedimentation effect, and the sedimentation time is 20-30min. Then the drain/sludge valve 27 is opened, and the sludge is discharged with the water flow through the sludge pipe 21 to complete the backwashing process.

(3) The reset process of the light filter material layer: After the backwashing is completed and the mud is discharged, the light filter material layer needs to be reset before the next filtration process. First, close the drain/sludge valve 27 and the backwash air valve 28, open the micro-water spray inlet valve 30 and valve 31, open the connecting valve 29 and the exhaust valve 9, start the micro-water spray pump 19, and start the micro-water spray pump 19 Under the action of the washing water of the shower pump 19, the water flow is sprayed from the filter aid nozzle 24 into the reactor 1. The water level in the reactor 1 gradually rises, and the expandable polystyrene particle (EPS) filter material 36 is because of the specific gravity ratio. The water is small, and the automatic reset is realized under the support of this rising water flow. At the same time, the micro-water spray assists in the adjustment of the distribution of the lightweight filter material during the ascending process, and the effect of the rising filter material on the anti-floating filter plate and the water flow upward Under the pressure, the filter layer is gradually compacted. At this time, close the micro-water spray inlet valve 30 and valve 31, continue to keep the micro-water spray pump 19 running for 5 minutes, close the micro-water spray pump 19 and the connecting valve 29, complete The reset process of the filter layer.

(3) Reactor maintenance: The reactor has been running for about 1 year, and the filter material needs to be supplemented or replaced. When replenishing or replacing the filter material, open the drain/sludge valve 27, the backwashing aid valve 30 and the valve 31, and close the valve 25, the backwash air valve 28 and the connecting valve 29. The filter material moves down with the water level and waits for the liquid level. When the detecting instrument 34 shows that the water level drops below the lower edge of the filter material replacement port, close the drain/sludge valve 27, stop the backflush water pump 19, open the filter material replacement port 33, and replenish or replace the filter material; add the filter material When finished, close the filter replacement port 33, and start filtering according to the filtering process operation.

In this embodiment, the filter reactor is used to perform advanced treatment on the effluent after the secondary settling tank of a sewage treatment plant. It can be seen from Table 1 that the reactor has a very good removal effect on turbidity in water. The turbidity of the influent water of the reactor is 7.134～36.270 NTU, the turbidity of the effluent of the reactor can reach below 1 NTU, and the turbidity removal rate is between 94.5% and 97.7%.

Table 1 Water quality treatment effect of different influent turbidity

It should be understood that those of ordinary skill in the art can make improvements or changes based on the above description, and all these improvements and changes should fall within the protection scope of the appended claims of the present invention.

Claims

A micro-water backwash variable-speed upward-flow lightweight filter material, which is characterized by comprising: a reactor (1), an influent water distribution system, an air backwash system, a micro-water backwash spray system, and a water collection system , Drainage/sludge system;

The inside of the reactor (1) is divided into water inlet/sludge discharge area (2), backwash stripping area (3), variable speed filter area (4), compaction filter area (5), water collection area (6); An anti-floating filter plate (12) is installed on the upper part of the solid filter area (5), a filter head (13) is installed on the anti-floating filter plate (12), and a cover plate (14) is installed directly above the anti-floating filter plate (12) , A deflector is arranged around the cover plate (14), and an exhaust valve (9) is arranged on the cover plate (14);

The water inlet/sludge discharge zone (2) is located at the bottom of the reactor (1), the backwash stripping zone (3) is located on the upper part of the water inlet zone (2), the backwash stripping zone (3) is cylindrical, and the backwash stripping The volume of the zone (3) is equal to the sum of the volume of the variable-speed filter zone (4) and the compacted filter zone (5), and the dirt in the water to be treated will be intercepted by the filter layer of the variable-speed filter zone first;

The variable-speed filter zone (4) is located in the upper part of the backwash stripping zone (3). The cross-sectional area of this zone gradually decreases from bottom to top, and it is in the shape of a truncated cone. Because the water flow rate is constant, the cross-sectional area decreases, and the filter material in this area The upward pressure on the filter layer also gradually increases;

The compacted filter zone (5) is located in the upper part of the variable-speed filter zone (4). This area is cylindrical, and its cross-sectional area is the same as the cross-sectional area of the upper part of the variable-speed filter zone (4). The water flow speed is the maximum water flow speed of the variable-speed filter zone (4), in which the filter material filter layer is subjected to the greatest pressure and the filter layer is the densest.
The filter according to claim 1, characterized in that the raw water to be treated enters the bottom of the reactor (1) through the water inlet/sludge discharge zone (2), and sequentially passes through the backwash stripping zone (3) and the variable speed filter zone (4). ) And the filter layer of the compaction filter zone (5) intercept and filter, the filtered water will meet the cover plate (14) through the filter head, and flow into the clear water tank (15) through the deflector of the cover plate (14), and then pass through The overflow weir (16) enters the water collection area (6), and finally the water is collected into the clear water tank (38) by the outlet pipe (17).
The filter according to claim 1, wherein the filter material filled in the reactor is expandable polystyrene particles (36) with a particle size specification of 0.5 to 1 mm.
The filter according to claim 1, wherein the inlet water distribution system comprises: a raw water tank (37), a water pump (18), a raw water inlet pipe (10), a water inlet valve (25) and a reflector (11) ; The water inlet valve (25) is installed on the raw water inlet pipe (10), and the reflector plate (11) is located directly under the inlet pipe to distribute water evenly; the raw water tank (37) is connected to the water inlet of the water pump (18), and the water pump ( 18) The water outlet is connected to the raw water inlet pipe (10) and the water inlet valve (25), and the reflector plate (11) is located directly below the nozzle of the raw water inlet pipe (10). The water to be treated is pressurized by a water pump and transported into the water inlet/sludge discharge area (2) at the bottom of the reactor (1) through the raw water inlet pipe, and the influent water is uniformly distributed through the reflector (11).
The filter according to claim 1, wherein the water collection system includes a clear water outlet pipe (17) and a clear water tank (38), one end of the clear water outlet pipe (17) is connected to the water collection area (6), and the other end is connected to the water collection area (6). To the clear water tank (38), there is a gap between the catchment area and the clear water tank (38), and the clear water automatically flows into the clear water tank by using the gap.
The filter according to claim 1, wherein the micro-water backwash spray system includes a clean water pump (19), a micro-water backwash main pipe (23), a micro-water backwash valve (30) and a valve (31) , Micro-water recoil spray branch pipe (8) and filter aid washing nozzle (24), liquid level sensor (35) and liquid level detection instrument (34); clean water pump (19) is connected to clean water tank (38), The clean water pump (19) is connected to the micro-water recoil spray branch pipe (8) and the micro-water recoil spray branch pipe (8) through the micro-water recoil main pipe (23), the micro-water recoil valve (30), and the valve (31). Circumferentially arranged on the outside of the compaction filter zone (5) and the variable-speed filter zone (4), each micro-water backwash spray branch pipe (8) is provided with a plurality of filter aid washing nozzles (24) to pass the water into the pressure Inside the solid filter zone (5) and the variable speed filter zone (4); the liquid level sensor (35) is set on the top of the backwash stripping zone (3), and is connected with the liquid level detection instrument (34) through a data line, During the backwashing process, it is used to control the water level at the top of the backwashing stripping zone (3) according to the water level sensing result of the liquid level sensor (35).
The filter according to claim 1, wherein the air backwash system includes an air compressor (20), a backwash air pipe (22), a backwash air pipe nozzle (7), a backwash air valve (28) and a reverse Check valve (26), backwash air release valve (9). The drain pipe (21) of the reactor (1) is equipped with a drain/sludge valve (27); the backwash gas pipe (22) in the reactor (1) is set on the pipe section at the bottom of the backwash stripping zone (3) There are evenly distributed backwashing air pipe nozzles (7), and the backwashing air pipe (22) is equipped with a backwashing air valve (28) and a check valve (26) to prevent water pouring; the top cover of the reactor (1) There is an exhaust valve (9);
The filter according to claim 1, characterized in that the drainage/sludge system includes a drainage/sludge pipe (21), a drainage/sludge valve (27), and the drainage/sludge pipe (21) is arranged at the inlet /At the bottom of the sludge area (2), a drain/sludge valve (27) is provided on the drain/sludge pipe (21).
The operation method of the filter according to claim 1, characterized in that the operation process of the micro-water backflush variable speed upward flow light filter material filter is divided into: (1) filtration process; (2) backwash Process; (3) The reset process of the light filter material layer; the three processes are carried out in cycles;

(1) Filtration process: Close the drain/sludge valve (27), the backwash inlet valve (28) and the connecting valve (29), open the water inlet valve (25) and exhaust valve (9), and start the water inlet pump ( 18), the water to be treated in the raw water tank (37) is transported into the reactor (1) through the inlet pipe (10) by the water pump (18), and the water to be treated flows from the inlet pipe (10) through the reflector (11) for uniformity Water distribution, the filtered water flows upwards through the backwash stripping zone (3), variable speed filter zone (4), compaction filter zone (5), and finally the water flows through the filter head into the clear water zone, when the rising water flow meets the cover plate (14) , The effluent is discharged from the exhaust pipe first, then close the exhaust valve (9), let the water flow into the clear water tank (15) through the deflector, and then into the catchment area (6) through the overflow weir (16), and finally pass The outlet pipe (17) enters the clean water tank (38).

(2) Backwashing process: close the water inlet valve (25), open the drain/sludge valve (27), the water level in the reactor (1) gradually drops as water is discharged from the drain/sludge valve (27), The filter material also drops accordingly. At this time, open the connecting valve (29), the micro water inlet regulating valve (30) and the valve (31), start the micro water spray pump (19), and use the filter material to help wash the spray holes (24). The spraying action of) promotes the dispersion and downward movement of the filter material in the compacted filter zone (5), and finally uses the liquid level sensor (35) and the liquid level detection instrument (34) to control the water level at the top of the backwash stripping zone (3) . At this time, close the communication valve (29), the micro-water inlet regulating valve (30) and the valve (31), close the micro-water spray pump (19), open the air backwash valve (28), and the exhaust valve (9), Start the air pump (20). After the gas is pressurized by the air compressor (20), it enters the reactor through the air pipe (20), the air volume regulating valve (28), and the check valve (26), and then passes through the backwashing air pipe nozzle (7) Blow out and stir the light filter material for 5-10min, so that the dirt trapped by the filter layer will be peeled from the filter material by the shearing action of the gas and its own gravity, and then turn off the air compressor (20) and The valve (28) uses sedimentation to collect the stripped impurities in the drainage/sludge discharge area (2). The sedimentation time is 20-30min, and then the drainage/sludge valve (27) is opened to allow the sludge to pass through the sludge discharge pipe (21). ) Discharge with the water flow to complete the backwashing process.

(3) The reset process of the light filter material layer: After the backwashing is completed and the mud is discharged, the light filter material layer needs to be reset before the next filtration process. First, close the drain/sludge valve (27) and the backwash air valve (28), open the micro-water spray inlet valve (30) and valve (31), open the connecting valve (29) and the exhaust valve (9), Start the micro-water spray pump (19), under the action of the washing water of the micro-water spray pump (19), the water flow is sprayed from the filter aid spray hole (24) into the reactor (1), the reactor (1) ) The internal water level gradually rises. Because the specific gravity of the expandable polystyrene particle (EPS) filter material (36) is smaller than that of water, it can automatically reset under the support of this rising water flow. At the same time, the slight water spray will affect the rising process. The light filter material distribution is adjusted auxiliary. The rising filter material is blocked by the anti-floating filter plate and the filter layer is gradually compacted under the force of the water flow upwards. At this time, close the micro water spray inlet valve (30) and the valve ( 31), after continuing to keep the micro-water spray pump (19) running for 5-10 minutes, close the micro-water spray pump (19) and the connecting valve (29) to complete the reset process of the filter layer.