Filtration and ultrafiltration assembly of skid-mounted treatment equipment for coal bed gas drainage and mining water

Abstract

The utility model discloses a filtration and ultrafiltration assembly of skid-mounted treatment equipment for coal bed gas drainage and mining water, which solves the problem of how to remove macromolecular organic matters in water according to the characteristics of the drainage and mining water. A quartz sand filtering layer (402) is arranged in the homogeneous filtering barrel (401), a homogeneous filtering water output pipeline (404) is connected to a water output port of the homogeneous filtering barrel (401), the other end of the homogeneous filtering water output pipeline (404) is connected with a water input port of a middle water tank (406), a water output port of the middle water tank (406) is connected with a bag type filter (408) through an ultrafiltration water pump (407), and the bag type filter (408) is connected with a water outlet of the middle water tank (406). The output end of the bag type filter (408) is connected with a bag type filter output water pipeline (409), the bag type filter output water pipeline (409) is connected with an ultrafiltration filter (410) in parallel, and the other end of an ultrafiltration filter output pipeline (411) is connected with a purified water tank (412).

Description

Technical Field

[0001] The utility model relates to a water pollution treatment device, in particular to a filtration and ultrafiltration component of a skid-mounted treatment device for coalbed methane drainage water. Background Art

[0002] At present, the water pollution risk brought by coalbed methane exploitation is becoming increasingly prominent; during the process of coalbed methane exploitation, with the extraction of the coalbed gas being exploited, a large amount of drainage water will be discharged from the gas wells. The drainage water contains pollutants such as suspended solids, organic matter, fluorides, petroleum substances, etc. Especially, the chemical agents used in coalbed methane drilling and exploitation will also enter the produced water during the exploitation process, causing serious water pollution to the drainage water; the existing coalbed methane wells are relatively scattered, generally scattered in mountainous and hilly areas, with farmland and rivers nearby; the drainage water generated by multiple gas wells on-site generally needs to be collected, and the collected drainage water must be treated to remove the pollutants in the water. The treated drainage water is generally discharged locally into the surface river; therefore, the pollution treatment of coalbed methane drainage water has become a top priority for the local society and production enterprises.

[0003] Regarding the treatment of coalbed methane drainage water, if treated by referring to traditional industrial wastewater, a ground sewage treatment station needs to be built, which requires land acquisition and corresponding water treatment equipment, and has the defects of long construction time and large floor area; due to the dispersion of coalbed methane wells and the limited continuous exploitation time, it is neither economical nor practical to equip a ground fixed sewage treatment station beside the gas wells; how to design a movable integral treatment device for drainage water and realize convenient movement according to the on-site situation has become an urgent requirement for coalbed methane drainage water treatment.

[0004] The main pollutants in coalbed methane drainage water are suspended solids, colloids, macromolecular organic matter, fluorides, ammonia nitrogen, etc. Generally, the water treatment method of coagulation → sedimentation → sand filtration → ultrafiltration is adopted. The ultrafiltration link mainly removes macromolecular organic matter in the sewage. According to environmental protection requirements, the quality of the discharged water should reach the third class of surface water. How to design the sand filtration and ultrafiltration device in the skid-mounted water treatment device according to the characteristics of coalbed methane drainage water and the integral sewage treatment device is a topic that needs to be studied for the skid-mounted device. Summary of the Invention

[0005] The utility model provides a sand filtration and ultrafiltration component of a skid-mounted treatment device for coalbed methane drainage water, and solves the technical problem of how to remove macromolecular organic matter in water according to the characteristics of drainage water.

[0006] The utility model solves the above technical problems through the following technical solutions:

[0007] The filtering and ultrafiltration components of a skid-mounted treatment device for coalbed methane drainage water include a homogeneous filtering device, an intermediate water tank, a precision filter, an ultrafiltration device, and a purification water tank. A quartz sand filtering layer is provided in the homogeneous filtering device, and a gas-water dual-purpose filtering cap is provided on the lower bottom surface of the quartz sand filtering layer. The water inlet of the homogeneous filtering device is communicated with the water outlet of the water collecting tank of the inclined tube sedimentation area. A homogeneous filtering effluent pipeline is connected to the water outlet of the homogeneous filtering device, and the other end of the homogeneous filtering effluent pipeline is connected to the water inlet of the intermediate water tank. The water outlet of the intermediate water tank is connected to the precision filter through an ultrafiltration water pump. A precision filter effluent pipeline is connected to the output end of the precision filter. An ultrafiltration device is connected in series on the precision filter effluent pipeline. An effluent pipeline of the ultrafiltration device is provided at the output end of the ultrafiltration device, and the other end of the effluent pipeline of the ultrafiltration device is connected to a purification water tank. A discharged water pipeline is connected to the purification water tank.

[0008] An anti-flushing water pump is connected in parallel on the homogeneous filtering effluent pipeline; a chemical cleaning pipeline is connected to the water inlet of the precision filter, the other end of the chemical cleaning pipeline is connected to a chemical cleaning agent storage tank, and a chemical cleaning pump is provided on the chemical cleaning pipeline; a gas cleaning pipeline is connected to the precision filter effluent pipeline, and an air compressor pump is connected to the gas cleaning pipeline.

[0009] The utility model first obtains clear water after flocculation sedimentation of the coalbed methane drainage sewage, and then performs homogeneous filtration and ultrafiltration on the obtained clear water, so that the discharged water can meet the national discharge requirements, realizing the harmless discharge of the coalbed methane drainage sewage after treatment. Description of the Drawings

[0010] Figure 1 is a structural schematic diagram of the utility model. Detailed Embodiment

[0011] The present utility model will be described in detail below with reference to the drawings:

[0012] The filtration and ultrafiltration components of a skid-mounted treatment device for coalbed methane drainage water include a homogeneous filtration device 401, an intermediate water tank 406, a precision filter 408, an ultrafiltration device 410, and a purification water tank 412. A quartz sand filtration layer 402 is provided in the homogeneous filtration device 401, and a gas-water dual-purpose filtration cap 403 is provided on the lower bottom surface of the quartz sand filtration layer 402. The water inlet of the homogeneous filtration device 401 is connected to the water outlet of the collection trough 305 in the inclined tube sedimentation area. A homogeneous filtration effluent pipeline 404 is connected to the water outlet of the homogeneous filtration device 401, and the other end of the homogeneous filtration effluent pipeline 404 is connected to the water inlet of the intermediate water tank 406. The water flowing from the collection trough 305 in the inclined plate sedimentation area by gravity passes through the quartz sand filtration layer 402 and then enters the intermediate water tank 406. The effluent pipeline of the intermediate water tank 406 is connected to the precision filter 408 through an ultrafiltration water pump 407. A precision filter effluent pipeline 409 is connected to the output end of the precision filter 408. An ultrafiltration device 410 is connected in series on the precision filter effluent pipeline 409. An ultrafiltration device effluent pipeline 411 is connected in series to the output end of the ultrafiltration device 410. The other end of the ultrafiltration device effluent pipeline 411 is connected to a purification water tank 412. A discharge water pipeline 413 is connected to the purification water tank 412. The water in the intermediate water tank 406 enters the purification water tank 412 after passing through the precision filter and the ultrafiltration device 410.

[0013] A backwash water pump 405 is connected in parallel to the homogeneous filtration effluent pipeline 404. A chemical cleaning pipeline 416 is connected to the water inlet of the precision filter 408, and the other end of the chemical cleaning pipeline 416 is connected to a chemical cleaning agent storage tank 418. A chemical cleaning pump 417 is provided on the chemical cleaning pipeline 416. An air washing pipeline 414 is connected to the precision filter effluent pipeline 409, and an air compressor pump 415 is connected to the air washing pipeline 414 to realize the cleaning of the precision filter 408 and the ultrafiltration device 410.

[0014] The homogeneous filtration device consists of a filter chamber, filter plates, air-water dual-purpose filter caps, and homogeneous quartz sand filter media. The filtered water slowly seeps in from the upper part of the quartz sand filtration layer 402. Through the interception and adsorption of the homogeneous filter media, the suspended solids, colloids, etc. remaining in the water are removed, making the water quality clearer and more transparent, and the effluent turbidity is less than or equal to 1.0 NTU. After the quartz sand filtration layer 402 operates for a period of time, a large amount of suspended solids are intercepted in the filter media, the pores between the filter media become smaller, the filtration rate increases, and the treated water volume decreases. At this time, effective flushing must be carried out to restore it. The backwashing procedure is to first perform air washing. Through the friction of air, the suspended solids, exfoliation, etc. adhered to the filter media are dispersed, and then water washing is carried out. The dispersed suspended solids, colloids, etc. and water enter the regulation tank at the same time for re-treatment. The ultrafiltration device is a low-pressure membrane separation technology. The filtration process is a pure mechanical screening process driven by the pressure difference across the membrane, with different rejection rates of substances with different molecular weights in the feed liquid depending on the size of the membrane pores. The pressure used in ultrafiltration is usually 0.01 - 0.3 Mpa, the screening pore size is approximately in the range of 0.1 - 0.002 microns, and the molecular weight cut-off is approximately 1000 - 500000 Daltons. The separation mechanism of the ultrafiltration process is mainly the mechanical interception (screening) of solutes with a particle size larger than the membrane pores on the membrane surface. Screening is the main mechanism of the ultrafiltration process. Dissolved substances and substances with a size smaller than the membrane pore size will pass through the ultrafiltration membrane with the permeate, and the substances that cannot pass through will be gradually concentrated in the discharge liquid. Therefore, the produced water (permeate) contains water, ions, and small molecule substances, while colloidal substances, particles, bacteria, viruses, and protozoa will be removed by the membrane. The ultrafiltration membrane can be reused and can be cleaned with chemical cleaning agents. The effluent of the ultrafiltration equipment enters the clear water tank and is discharged locally after reaching the Class III standard of the "Surface Water Environment Quality Standard" (GB3838 - 2002). According to the pollution situation of the ultrafiltration membrane operation, a specific cleaning solution with a certain concentration is prepared to remove the pollutants in the ultrafiltration membrane to restore the original characteristics of the membrane. No matter how good the pretreatment is, after long-term use, the membrane surface will still be fouled by scaling. Therefore, a cleaning system is set up in this system. When the membrane module is polluted, chemical cleaning can be carried out.

Claims

1. A filtration and ultrafiltration component of a skid-mounted treatment device for coalbed methane drainage water, comprising a homogenizing filtration device (401), an intermediate water tank (406), a precision filter (408), an ultrafiltration device (410) and a purified water tank (412), characterized in that: A quartz sand filter layer (402) is provided in the homogeneous filter device (401), and an air-water dual-purpose filter cap (403) is provided on the lower bottom surface of the quartz sand filter layer (402). The water inlet of the homogeneous filter device (401) is connected to the water outlet of the water collecting tank (305) in the inclined tube sedimentation area. A homogeneous filter water outlet pipe (404) is connected to the water outlet of the homogeneous filter device (401), and the other end of the homogeneous filter water outlet pipe (404) is connected to the water inlet of the intermediate water tank (406). The water outlet is connected to the precision filter (408) through an ultrafiltration water pump (407); a precision filter water outlet pipe (409) is connected to the output end of the precision filter (408); an ultrafiltration device (410) is connected in series to the precision filter water outlet pipe (409); a water outlet pipe (411) of the ultrafiltration device is arranged at the output end of the ultrafiltration device (410); the other end of the water outlet pipe (411) of the ultrafiltration device is connected to a purified water tank (412); and a discharge water pipe (413) is connected to the purified water tank (412).

2. The filtration and ultrafiltration component of the skid-mounted treatment equipment for coalbed methane drainage water according to claim 1, characterized in that: A backwash water pump (405) is connected in parallel to the homogenizing filter outlet pipe (404); a chemical cleaning pipe (416) is connected to the water inlet of the precision filter (408); the other end of the chemical cleaning pipe (416) is connected to a chemical cleaning agent storage tank (418); a chemical cleaning pump (417) is provided on the chemical cleaning pipe (416); an air washing pipe (414) is connected to the precision filter outlet pipe (409); and an air compression pump (415) is connected to the air washing pipe (414).

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