Particulate matter filtering system and particulate matter-containing wastewater treatment method

Abstract

The invention discloses a particulate matter filtering system and a particulate matter-containing wastewater treatment method.The particulate matter filtering system comprises a rack and a filter body, a plurality of filter elements are arranged in the filter body, the filter elements are connected with a liquid outlet pipe on the upper portion of the filter body, the liquid outlet pipe is connected with a liquid purifying valve, and a liquid inlet pipe and a blow-off pipe are arranged on the lower portion of the filter body; the liquid inlet pipe is connected with the liquid inlet valve, and the blow-off pipe is connected with the blow-off valve and the dirty liquid valve; a slag discharge port and a slag discharge valve are arranged at the bottom of the filter; a plurality of supports are arranged on the periphery of the filter main body and are mounted on the rack through weighing sensors; and the liquid inlet pipe, the liquid outlet pipe and the blow-off pipe are connected with an external pipeline through flexible joints. The weighing sensor is used for measuring the weight increment value of the filter and transmitting the weight increment value to the PLC control system, the PLC system monitors the weight increment value of the filter in real time, and a judgment basis is provided for the deslagging time.

Description

Technical Field

[0001] The invention relates to the field of particle or powder filtering system, in particular to the field of particle filtering. Background Art

[0002] At present, many manufacturers apply candle filters to the filtration of particulate matter or powder. One or more filter elements are arranged in the cylinder of the filter. The filter element is covered with a special filter cloth selected according to the characteristics of the raw liquid. When the liquid passes through the filter cloth, the solid matter in the liquid will gradually gather on the surface of the filter cloth. When these solid substances reach a certain thickness, the so-called "filter cake layer" is formed. Since the gaps between the particles in the filter cake layer are very small, the escape of particulate impurities in the liquid is blocked, so that the filtrate becomes clear and the filtration effect required for production is achieved; after a period of normal filtration, the filter cake layer exceeds a certain thickness, the rate at which the filtrate passes through the filter cake layer decreases, and the filtration efficiency becomes poor, and it is necessary to remove the residual liquid on the filter cake layer.

[0003] Filter wastewater containing particles or powders with good porosity and low viscosity. Even if a thick filter cake is formed, it can still be filtered continuously. Although the tank is already blocked, liquid has been flowing out of the liquid outlet. If the tank is blocked, subsequent slag discharge is very difficult. Some existing technologies use time, flow rate, and pressure difference detection to determine whether to clean the filter element and discharge the tank. However, for particles with good porosity, the flow rate will not decrease and the pressure difference will not change much. Therefore, it is difficult to determine the timing of slag discharge by pressure difference and flow rate.

[0004] In the existing bottom-in and top-out candle filters, after the residual liquid is discharged through the sewage pipe, some residual liquid remains in the filter element, resulting in insufficient filter cake thickness. When the residue is discharged, there is still residue liquid with extremely high water content, which makes it difficult to recover the filter residue.

[0005] At present, many candle filters, once ready to discharge slag, close the liquid inlet valve and the liquid outlet valve, and directly discharge the entire tank of liquid through the drain pipe. If the tank size is large, the entire tank of liquid is discharged without filtering, resulting in great waste. Summary of the invention

[0006] In view of the problems existing in the prior art, the present invention provides a particle filtering system. The present invention is implemented through the following technical solutions:

[0007] A particle filtering system comprises a frame and a filter body, wherein a plurality of filter elements are arranged inside the filter body, and the filter elements are connected to a liquid outlet pipe outside the filter body, a plurality of supports are arranged on the periphery of the filter, and the plurality of supports are mounted on the frame through a weighing sensor, and a liquid inlet pipe and a sewage discharge pipe are arranged below the tank body, and the liquid inlet pipe, sewage discharge pipe and liquid outlet pipe are all connected to an external pipeline through a flexible joint.

[0008] Furthermore, the liquid outlet pipe is connected to the clean liquid valve, the liquid inlet pipe is connected to the liquid inlet valve, the sewage pipe is connected to the sewage valve and the sewage valve; and a slag discharge port and a slag discharge valve are provided at the bottom of the filter body.

[0009] Furthermore, the filter body comprises a tank body and a gland, the filter element passes through the gland and is connected to the liquid outlet pipe, and the filter element has an extension section, the extension section passes through the gland and is sealed and connected to the gland.

[0010] Furthermore, a plurality of air holes are provided on the wall of the filter body, the air holes are connected to an air inlet pipe, the air inlet pipe is connected to an air inlet valve, the liquid outlet pipe is connected to a first air outlet pipe, and the first air outlet pipe is connected to a first air outlet valve.

[0011] Furthermore, the liquid outlet pipe is also connected to a pulse air pipe for spraying into the interior of the filter element, the pulse air pipe is connected to a pulse valve, and the air inlet pipe is also connected to a second air outlet pipe and a second air outlet valve.

[0012] Furthermore, a scraper is provided on the filter element, a through hole is provided on the scraper for the filter element to pass through, the scraper is connected to a lifting drive mechanism, and a guide mechanism for positioning the scraper to lift is also provided in the filter body.

[0013] The present invention also provides a particle filtration system for a particle-containing wastewater treatment method, the particle-containing wastewater treatment method comprising the following steps:

[0014] S1. Open the liquid inlet valve and the dirty liquid valve, and introduce wastewater into the filter tank through the liquid inlet pipe for continuous filtering. When the filter cake is formed to a certain thickness, the liquid outlet pipe begins to discharge clear liquid. Close the dirty liquid valve, open the clean liquid valve, and record the weight increment of the filter at this time as the lower limit value.

[0015] S2. Continue to introduce wastewater into the tank through the liquid inlet pipe for continuous filtering. The weighing sensor transmits the real-time filter weight increment to the PLC system. When the real-time filter weight increment reaches the upper limit, the liquid inlet valve is closed.

[0016] S3, open the first air inlet valve, and introduce high-pressure gas into the tank through the air hole. Under the action of the internal pressure of the tank, the clean liquid continues to be discharged from the liquid outlet pipe;

[0017] S4. When the liquid outlet pipe does not discharge clean liquid, close the clean liquid valve, open the sewage valve and the sewage valve, and drain the remaining sewage in the tank through the sewage pipe;

[0018] S5, open the first air outlet valve, close the sewage valve and the waste liquid valve, and continue to introduce high-pressure gas into the tank through the air hole to dry the filter element from the outside to the inside;

[0019] S6. Close the first air inlet valve, open the second air outlet valve, release the pressure in the tank, and open the slag discharge valve to discharge the slag.

[0020] Furthermore, in steps S1 and S2, the incremental weight value of the filter is set as follows: wastewater is introduced into the filter through the liquid inlet pipe to fill the tank, the filter filled with wastewater is weighed using a weighing sensor, the weight value is recorded, and reset in the PLC control system; the PLC system automatically peels off the real-time changing filter weight, that is, the real-time changing filter weight minus the filter weight filled with wastewater is used as the incremental weight value of the filter.

[0021] Furthermore, in S2, the upper limit of the filter weight increment is calculated based on the maximum thickness of the filter cake.

[0022] Furthermore, the processing method comprises the following steps:

[0023] S7. After the slag discharge valve is opened, open the pulse valve and use the pulse air pipe to blow the inside of the filter element to blow the particles on the outer surface of the filter element apart;

[0024] S8. After the pulse air pipe is sprayed, the particles on the surface of the filter element are scraped off by a scraper and discharged from the slag discharge port.

[0025] Beneficial technical effects of the present invention:

[0026] The weight increment of the filter is measured by a weighing sensor and transmitted to the PLC control system. The PLC system monitors the weight increment of the filter in real time. When the weight increment of the filter reaches the set upper limit, it is ready to discharge the slag to avoid the tank being filled with particulate matter, which makes it difficult to discharge the slag.

[0027] Before the filter treats wastewater, it is first filled with wastewater. The PLC system then measures the filter weight value and de-tares it to obtain the filter weight increment value. Only the filter weight increment is monitored, which makes the measurement more accurate.

[0028] Before discharging slag, high-pressure gas is introduced first, and only the liquid inlet valve is closed. Under the action of gas pressure and the pressure inside the tank, the liquid in the tank continues to be discharged through the liquid outlet pipe, and the clean liquid recovery rate is higher.

[0029] After the particles adsorbed by the filter element are blown dry, the pulse air pipe is used to spray the inside of the filter element to blow the particles on the outer surface of the filter element apart, which is conducive to the removal of the filter cake. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The figure is a working flow chart of the particle filtering system of the present invention.

[0031] Figure 2 Schematic diagram of the three-dimensional structure of the particulate matter filtration system.

[0032] Figure 3 Schematic diagram of filter cake structure.

[0033] In the figure: filter 1, pressure cover 10, tank body 11, air inlet 110, support 111, filter element 12, filter cake 120, slag discharge port 13, slag discharge valve 130, scraper 14, frame 2, weighing sensor 3, liquid inlet pipe 4, liquid inlet valve 41, pump 42, wastewater tank 43, liquid outlet manifold 5, liquid outlet branch pipe 51, clean liquid valve 52, clean liquid tank 53, sewage pipe 6, sewage valve 61, sewage valve 62, air inlet pipe 7, air inlet valve 71, first air outlet pipe 8, first air outlet valve 81, pulse air pipe 9, pulse valve 91, second air outlet pipe 20, second air outlet valve 201, slag receiving car 21, flexible joint 300. DETAILED DESCRIPTION

[0034] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0035] like Figure 1 , Figure 2 As shown, the particle filtering system includes a filter body 1 and a frame 2, and the filter body 1 is installed on the frame 2 through a support 111. A plurality of filter elements 12 are arranged inside the filter body 1, and the filter elements 12 are connected to the liquid outlet branch pipe 51 at the upper part of the filter body 1, and the liquid outlet branch pipe 51 is connected to the liquid outlet manifold 5 after merging, and the liquid outlet manifold 5 is connected to the clean liquid valve 52 and the clean liquid pool 53, and the liquid outlet pipe transports the clean liquid to the clean liquid pool 53. A liquid inlet pipe 4 is arranged below the filter body 1, and the liquid inlet pipe 4 is connected to the liquid inlet valve 41, the pump 42, and the wastewater pool 43, and the wastewater pool 43 transports the wastewater into the filter body 1 through the pump 42. A sewage pipe 6 is also arranged below the filter body 1, and the sewage pipe 6 is connected to the sewage valve 61 and the sewage valve 62, and the sewage discharged from the sewage pipe can be recovered to the sewage pool 43. A slag discharge port 13 is arranged at the bottom of the filter body 1, and a slag discharge valve 130 is arranged at the slag discharge port 13. A slag receiving car 21 is arranged below the slag discharge port 13. A filter screen is arranged inside the slag receiving car 21. The filter screen divides the slag receiving car into two upper and lower chambers. After the filter screen separates the slag and liquid, the waste liquid can be recovered to the waste liquid pool 43, and the waste slag is transported to a designated recovery point by a trolley.

[0036] like Figure 2 As shown, a plurality of supports 111 are distributed on the periphery of the filter body 1, and the supports 111 are mounted on the frame 2 through the weighing sensor 3, and the supports 111 are overlapped on the weighing sensor, and the weighing sensor 3 is fixedly connected to the frame 2 through a connector. The weighing sensor 3 is electrically connected to the PLC control system, and the weighing sensor 3 transmits the filter weight increment information to the PLC control system.

[0037] like Figure 2As shown, the liquid inlet pipe 4, the sewage pipe 6, and the liquid outlet manifold 5 are all connected to the external pipeline through a flexible joint 300, and the flexible joint adopts a steel hose. The liquid outlet branch pipe 51 adopts a lightweight plastic pipe. The liquid outlet manifold 5 is divided into two liquid outlets, one of which is connected to the clean liquid pipe, and a clean liquid valve 52 is provided on the clean liquid pipe, and the other is connected to the dirty liquid pipe, and a dirty liquid valve 62 is provided on the dirty liquid pipe.

[0038] like Figure 1 When the filter element has not formed a filter cake, the liquid outlet manifold 5 discharges turbid liquid. Open the dirty liquid valve 62 and the turbid liquid is discharged from the dirty liquid pipe. When the filter cake is formed and reaches a certain thickness, clean liquid is discharged from the liquid outlet manifold 5. Close the dirty liquid valve 62, open the clean liquid valve 52, and the clean liquid is output to the clean liquid pool 53. At this time, the filter weight increment value is recorded as the lower limit value.

[0039] like Figure 2 The filter body 1 also includes a gland 10 and a tank body 11, and the gland 10 and the tank body 11 are sealed and connected by a connector. The filter element 12 passes through the gland 10 and is connected to the liquid outlet branch 51. The filter element 12 has an extension section, which passes through the gland 10 and is sealed and connected to the gland 10. There is no need to open the gland 10. The filter element 12 can be taken out from the through hole on the gland alone. The filter element is easy to take out and the thickness of the filter cake is easy to check. The gland 10 is provided with a pressure gauge and a pressure sensor connected to the inside of the tank body.

[0040] When the filter cake thickness continues to increase, you can set the time parameter to determine whether to remove the filter element. Take it out to check whether there is a small amount of filter cake falling off, so as to determine the maximum filter cake thickness. According to the maximum filter cake thickness, the maximum weight increment of the filter can be calculated. When the filter weight increment reaches the upper limit, stop feeding liquid and prepare for slag discharge.

[0041] A plurality of air holes 110 are provided on the wall of the tank body 11 , and the air holes 110 are connected to the air inlet pipe 7 , and the air inlet pipe 7 is connected to the air inlet valve 71 ; the liquid outlet manifold 5 is also connected to the first air outlet pipe 8 , and the first air outlet pipe is connected to the first air outlet valve 81 .

[0042] The liquid outlet manifold 5 is also connected to a pulse air pipe 9 for spraying into the filter element, and the pulse air pipe 9 is connected to a pulse valve 91 ; the air inlet pipe 7 connected to the wall of the tank body 11 is also connected to a second air outlet pipe 20 , and the second air outlet pipe 20 is connected to a second air outlet valve 201 .

[0043] like Figure 1 As shown, a scraper 14 is provided in the tank body, and a through hole is provided on the scraper 14 for the filter element to pass through. The scraper is connected to the lifting drive mechanism, and a guide mechanism for positioning the scraper lifting is also provided in the tank body. The filter cake sprayed by the pulse air pipe is scraped downward by the scraper, and the filter cake is cleaned more thoroughly.

[0044] Method for treating wastewater containing particulate matter by applying the above-mentioned particulate matter filtration system:

[0045] S1. Open the liquid inlet valve and the dirty liquid valve, and introduce wastewater into the filter tank through the liquid inlet pipe for continuous filtering. When the filter cake is formed to a certain thickness, the liquid outlet pipe begins to discharge clear liquid. Close the dirty liquid valve, open the clean liquid valve, and record the weight increment of the filter at this time as the lower limit value.

[0046] S2. Continue to introduce wastewater into the tank through the liquid inlet pipe for continuous filtering. The weighing sensor transmits the real-time filter weight increment to the PLC system. When the real-time filter weight increment reaches the upper limit, the liquid inlet valve is closed.

[0047] S3, open the first air inlet valve, and introduce high-pressure gas into the tank through the air hole. Under the action of the internal pressure of the tank, the clean liquid continues to be discharged from the liquid outlet pipe;

[0048] S4. When the liquid outlet pipe does not discharge clean liquid, close the clean liquid valve, open the sewage valve and the sewage valve, and drain the remaining sewage in the tank through the sewage pipe;

[0049] S5, open the first air outlet valve, close the sewage valve and the waste liquid valve, and continue to introduce high-pressure gas into the tank through the air hole to dry the filter element from the outside to the inside;

[0050] S6. Close the first air inlet valve, open the second air outlet valve, release the pressure in the tank, and open the slag discharge valve to discharge the slag.

[0051] The processing method further comprises the following steps:

[0052] S7. After the slag discharge valve is opened, open the pulse valve and use the pulse air pipe to blow the inside of the filter element to blow the particles on the outer surface of the filter element apart;

[0053] S8. After the pulse air pipe is sprayed, the particles on the surface of the filter element are scraped off by a scraper and discharged from the slag discharge port.

[0054] Use the pulse valve to spray inside the filter element to blow the particles on the outer surface of the filter element apart. You can also use tools such as scrapers to scrape off the burst filter cakes to clean the particles adsorbed on the surface of the filter element more thoroughly.

[0055] The weight increment value of the filter in steps S1 and S2 is set as follows: open the liquid inlet valve, introduce wastewater into the filter through the liquid inlet pipe, fill the tank, use the weighing sensor to weigh the filter filled with wastewater, record the weight value, and reset it in the PLC control system.

[0056] Wastewater containing particulate matter is composed of clean water and particulate matter, or of proportioning liquid and particulate matter. The weighing sensor transmits the real-time changing filter weight value to the PLC system, and the PLC system automatically decimates the real-time changing filter weight, that is, subtracts the real-time changing filter weight from the filter weight filled with wastewater, and uses this as the filter weight increment value.

[0057] In S2, the upper limit of the filter weight increment is calculated based on the maximum thickness of the filter cake.

[0058] like Figure 3 As shown, the filter weight increment value It is derived from the following formula: \Delta m=\left ( {{\rho}_{1}-{\rho}_{2}} \right )\left [ {\frac {\pi \left ( {{d}_{1}+2b} \right )^{2}-\pi {{d}_{1}}^{2}} {4}} \right ]h=\pi h\left ( {{\rho}_{1}-{\rho}_{2}} \right )\left ( {{b}^{2}+{d}_{1}b} \right ) ,in, is the solid particle density, is the density of clean water or proportioning liquid, is the outer diameter of the filter cloth, is the filter cake thickness, is the filter cake length.

[0059] then , ; As the filter cake thickness The increase in filter weight increment It shows a parabolic increase.

[0060] It can be seen that the filter cake reaches the maximum discharge thickness, that is, the filter weight increment value reaches the maximum value. mm, mm, kg / mm 3 , kg / mm 3 , maximum filter cake thickness mm, the corresponding weight increment is 6.6 kg, and the PLC system sets this weight increment as the upper limit. When the real-time weight increment in the tank reaches the upper limit, the slag is ready to be discharged.

[0061] The upper and lower limits of the filter weight increment are set. During the subsequent operation of the filter, when the filter weight increment reaches the lower limit, the dirty liquid valve is switched to the clean liquid valve, and the liquid outlet pipe starts to discharge clean liquid; when the filter weight increment reaches the upper limit, it is ready to discharge slag.

[0062] When using the detection values ​​of time, flow rate and pressure difference to judge the time of slag discharge, the weighing sensor can also be used as an auxiliary judgment method. For example, for fine dust particles, the flow rate and pressure difference can be used to judge the time of slag discharge, and the weighing sensor can be used as an auxiliary judgment method.

[0063] The above are only specific embodiments of the present invention, but the technical features of the present invention are not limited thereto. Any simple changes, equivalent replacements or modifications made based on the present invention to solve basically the same technical problems and achieve basically the same technical effects are all included in the protection scope of the present invention.

Claims

1. A particle filtering system, comprising a frame and a filter body, wherein a plurality of filter elements are arranged inside the filter body, and the filter elements are connected to a liquid outlet pipe outside the filter body, characterized in that: A plurality of supports are arranged on the periphery of the filter, and the plurality of supports are mounted on the frame through weighing sensors. A liquid inlet pipe and a sewage discharge pipe are arranged below the filter body, and the liquid inlet pipe, sewage discharge pipe and liquid outlet pipe are all connected to external pipelines through flexible joints.

2. A particle filtration system according to claim 1, characterized in that: The liquid outlet pipe is connected to the clean liquid valve, the liquid inlet pipe is connected to the liquid inlet valve, and the sewage pipe is connected to the sewage valve and the sewage valve; a slag discharge port and a slag discharge valve are provided at the bottom of the filter body.

3. A particle filtering system according to claim 1, characterized in that: The filter body comprises a tank body and a gland, the filter element passes through the gland and is connected to a liquid outlet pipe, and the filter element has an extension section, the extension section passes through the gland and is sealed and connected to the gland.

4. A particle filtration system according to any one of claim 1, characterized in that: A plurality of air holes are arranged on the wall of the filter body, the air holes are connected to an air inlet pipe, the air inlet pipe is connected to an air inlet valve, the liquid outlet pipe is connected to a first air outlet pipe, and the first air outlet pipe is connected to a first air outlet valve.

5. A particle filtering system according to claim 4, characterized in that: The liquid outlet pipe is further connected to a pulse air pipe for spraying into the interior of the filter element, the pulse air pipe is connected to a pulse valve, and the air inlet pipe is further connected to a second air outlet pipe and a second air outlet valve.

6. A particle filtering system according to claim 1, characterized in that: The filter element is provided with a scraper, the scraper is provided with a through hole through which the filter element passes, the scraper is connected to a lifting drive mechanism, and the filter body is also provided with a guide mechanism for positioning the scraper to lift.

7. A particle filtration system according to any one of claims 1 to 6 is used in a method for treating wastewater containing particles, wherein the method for treating wastewater containing particles is characterized in that: The following steps are involved: S1. Open the liquid inlet valve and the dirty liquid valve, and introduce wastewater into the filter tank through the liquid inlet pipe for continuous filtering. When the filter cake is formed to a certain thickness, the liquid outlet pipe begins to discharge clear liquid. Close the dirty liquid valve, open the clean liquid valve, and record the weight increment of the filter at this time as the lower limit value. S2. Continue to introduce wastewater into the tank through the liquid inlet pipe for continuous filtering. The weighing sensor transmits the real-time filter weight increment to the PLC system. When the real-time filter weight increment reaches the upper limit, the liquid inlet valve is closed. S3, open the first air inlet valve, and introduce high-pressure gas into the tank through the air hole. Under the action of the internal pressure of the tank, the clean liquid continues to be discharged from the liquid outlet pipe; S4. When the liquid outlet pipe does not discharge clean liquid, close the clean liquid valve, open the sewage valve and the sewage valve, and drain the remaining sewage in the tank through the sewage pipe; S5, open the first air outlet valve, close the sewage valve and the waste liquid valve, and continue to introduce high-pressure gas into the tank through the air hole to dry the filter element from the outside to the inside; S6. Close the first air inlet valve, open the second air outlet valve, release the pressure in the tank, and open the slag discharge valve to discharge the slag.

8. The method for treating wastewater containing particulate matter according to claim 7, characterized in that: In steps S1 and S2, the filter weight increment is set as follows: wastewater is introduced into the filter through the liquid inlet pipe to fill the tank, the filter filled with wastewater is weighed using a weighing sensor, the weight value is recorded, and reset in the PLC control system; the PLC system automatically tares the filter weight that changes in real time, that is, the weight of the filter that changes in real time minus the weight of the filter filled with wastewater is used as the filter weight increment.

9. The method for treating wastewater containing particulate matter according to claim 7, characterized in that: In step S2, the upper limit of the filter weight increment is calculated based on the maximum thickness of the filter cake.

10. The method for treating wastewater containing particulate matter according to claim 7, characterized in that: The processing method further comprises the following steps: S7. After the slag discharge valve is opened, open the pulse valve and use the pulse air pipe to blow the inside of the filter element to blow the particles on the outer surface of the filter element apart; S8. After the pulse air pipe is sprayed, the particles on the surface of the filter element are scraped off by a scraper and discharged from the slag discharge port.

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