Plant for purifying liquid media of mechanical impurities

Abstract

The invention relates to means for removing (filtering) mechanical impurities from various liquid media used in the chemical industry and other sectors, loss of which during filtration must be minimized for economic or environmental reasons. The present plant makes it possible to increase the economic efficiency and environmental safety of various chemical production facilities, reduce labour costs and prevent equipment downtime related to the need for the regeneration of filters.

Description

[0001] INSTALLATION FOR CLEANING LIQUID MEDIA FROM MECHANICAL IMPURITIES

[0002] The invention relates to means for cleaning from mechanical impurities

[0003] (filtration) of various liquid media used in the chemical industry and other sectors, the losses of which during filtration must be minimized for economic or environmental reasons. For example: aqueous solutions of alkanolamines with various functional additives, such as ethylene glycol methyl ethers and DR-, used for absorption removal of hydrogen sulfide and carbon dioxide in oil and gas refining and chemical plants; fertilizer solutions; liquid hydrocarbons; chemical synthesis products; galvanic electrolytes; other expensive and / or ecotoxic liquid media.

[0004] The invention is also applicable for purifying fresh and sea water from mechanical impurities when there is a technological need to minimize the volume of losses of the filtered medium and the volume of wastewater contaminated with mechanical impurities.

[0005] To assess the novelty of the claimed solution, we will consider a number of known technical means of a similar purpose, characterized by a set of features similar to the claimed installation.

[0006] The automatic self-cleaning automatic filter F450 (E) is known, which has pneumatic or electrical control and is used to separate solid particles in various media, such as sea water, river water or industrial water. The filter provides reliable and continuous filtration in various applications, such as cooling water cycles or water treatment plants. The filter can be operated at very low pressure (only > 0.7 bar) and is characterized by unrivaled low pressure losses, a compact design and virtually no maintenance. Thanks to the flexible combination of various design solutions and materials, the F450 can be easily adapted to specific production requirements, see https: / / www.sab-bremen.de / en / filters / automatikfilter / automatikfilter-f450.html. . The disadvantage of such a filter is the increased consumption of flushing liquid.

[0007] A membrane filter for cleaning liquid media from mechanical impurities is known according to Russian patent No. 2638845. The filter includes a vertical housing with a bottom and a cover, a filter element installed under the cover, a deflector located coaxially with the longitudinal axis of the housing and having the form of an axisymmetric geometric figure, the cross-section of which is made with a decrease in the direction towards the bottom, an inlet and outlet branch pipes brought out through the bottom, an outlet branch pipe passing through the cover, and valves on the inlet, outlet and outlet branch pipes. The device is additionally equipped with a nozzle installed coaxially with the longitudinal axis of the housing, wherein the deflector is fixed on the lower surface of the filter element.

[0008] The TEKLEEN automatic filter (https: / / www.tekleen.com / ru / water-filtration-101 / ) is known, which is self-cleaning and works due to the pressure in the pipeline, without requiring an external energy source. As water passes through the filter, dirt particles accumulate on the filter mesh. This leads to a gradual drop in water pressure. When it reaches a preset level, the backwash cycle is activated. The vacuum cleaning system forcibly sucks dirt from the inner surface of the filter mesh and removes it through the drain hole. The backwash cycle is performed without interrupting the main flow. The filter includes a vertical housing with a bottom and a cover, a filter element installed in the housing, high-pressure nozzles. The disadvantage is the increased consumption of flushing fluid, the complexity of regenerating the filter element with viscous contaminants and a finer degree of purification, the need to use only the filtered liquid for flushing.

[0009] Reversible absorption of acid gases by aqueous solutions of alkanolamines (monoethanolamine, diethanolamine, triethanolamine, methyldiethanolamine) is currently a widely used method for gas purification due to its versatility in relation to both CO2 and H2S, as well as its ability to handle large flows of incoming raw materials.

[0010] One of the weak points of this technology is the constant accumulation of mechanical impurities of various natures in the system (equipment corrosion products — iron sulfides and oxides, silicate dust brought by gas from fields, carbon sludge from adsorption absorbers based on activated carbon, solid products of thermal destruction of alkanolamines in local overheating zones, etc.). These mechanical impurities have a complex negative effect on the gas purification process, forming deposits in pipelines, under which corrosion processes intensify, which in turn are also a source of mechanical impurities, and also forming local overheating zones, which are sources of thermal destruction products of ethanolamines. Mechanical suspensions worsen the adsorption properties of activated carbon, and also participate in the stabilization of foam, which interferes with the absorption of acid gases (H2S and CO2).

[0011] High-quality filtration of aqueous solutions of alkanolamines in absorption gas cleaning systems is the most important technological operation, which, due to the multifactorial negative impact of mechanical impurities in aqueous solutions of alkanolamines, can improve the economic efficiency of gas cleaning in several directions at once, with minimal costs.

[0012] An automatic backwash filter (DFF filter machine) is known, https.7 / youtu.be / uXBof7i3O1Isi=Q_05Rz7ulJz5a-ie. Raw water enters the filter through the inlet flange and is distributed along the outer ring of the housing. The raw water then rises up in the filter housing and flows into a three-component filter drum. To ensure a uniform supply of solids to the filter element, the filter drum rotates at 5-7 rpm. Solids in the raw water are retained in segment-shaped holes on the outside of the filter drum, located outside the filter element. Purified water exits the filter through the clean water outlet.

[0013] There is an automatic self-cleaning filter Type JET Filter, see https: / / youtu.be / nbl BJjYJ9E?si=YPJkI4wa8IrKVBYu. Raw water passes through the holes in the pressure plate and enters the filter elements located behind them. A decrease in the cross-section leads to a proportional increase in the axial flow velocity in the filter elements by 5-7 m / s. At the end of the filter elements there is a conical container for collecting dirt, in which all the filter elements are collected. Raw water is filtered according to Bernoulli's law in the last third of the filter elements. Raw water passes through the filter elements from the inside to the outside. Then clean water flows around the dirt collection container and exits the JET filter on the clean water side. The axial flow velocity in the filter elements of 5-7 m / s directs dirt particles into the conical dirt collection container. The filter backwash process is initiated by a pressure drop (the pressure difference between the raw and clean water sides).An adjustable time relay in the electrical control system additionally ensures the filter backwash process.

[0014] The disadvantages of these filters are the high consumption of the medium itself for backwashing and the inability to work with fine filtration.

[0015] A device for cleaning liquid and gaseous media from mechanical impurities is known according to Russian patent No. 2681 193, comprising a vertically oriented housing with a bottom and a cover, a filter element installed inside the housing, at least one nozzle for feeding a flushing liquid, characterized in that the filter element is made cylindrical and is located along the length of the housing coaxially with its longitudinal axis, and along the length of the filter element there is a hollow element for feeding the flushing liquid with the possibility of moving along it by means of a linear actuator, wherein at least one high-pressure nozzle is located at one end of the element for feeding the flushing liquid, and the other end of the element for feeding the flushing liquid is connected to a high-pressure pump through a hose for feeding the flushing liquid,In this installation, the flushing fluid supply element can be made in the form of a rod and connected to a hose for supplying flushing fluid through a linear actuator or in the form of a high-pressure pipe having a connection to the carriage of a linear actuator made in the form of a pneumatic cylinder. The filter element has a cleaning fineness of up to 2 μm and can be made with the possibility of rotation, in addition, it can be made corrugated and contain two high-pressure nozzles placed through a rotary device.

[0016] This technical solution, as the closest to the declared one in terms of technical essence and the achieved result, was accepted as its prototype.

[0017] This unit allows for high-pressure (up to 200 bar) flushing of the filter element during the flushing process. The use of high-pressure nozzles allows for cleaning the surface of the filter element with minimal flushing fluid consumption. The ability to use any fluid is ensured by the fact that the flushing line is isolated from the filtered medium.

[0018] The disadvantages of the prototype are:

[0019] 1. The absence of a system for minimizing losses of the filtered medium in the form of a return mechanism for repeated subsequent filtration of the contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element.

[0020] 2. The absence of a mechanism for returning the purified liquid medium remaining in the filter housing after stopping the filtration process before washing the filter element to the filtered medium collector, which leads to losses of purified liquid medium during the washing cycle.

[0021] 3. The lack of separation of the filter housing into “dirty” and “clean” zones, and the lack of a system for removing flushing liquid from the “clean” zone of the filter housing during flushing of the filter element into the drainage manifold, which can lead, after the resumption of the filtration process, to contamination of the purified liquid medium with flushing liquid and mechanical impurities entering the “clean” zone of the filter housing due to the high pressure of the flushing liquid used when flushing the filter element.

[0022] 4. The absence of a mechanism that ensures rotation of the nozzle(s) around the axis of the flushing fluid supply element leads to an increase in the time it takes to flush the filter element and to an increase in the consumption of flushing fluid.

[0023] 5. It is impossible to direct the flow of the filtered medium during the washing of the filter element to another parallel-connected filter of a similar or different design to ensure the continuity of the filtration process.

[0024] 6. Lack of means for determining the degree of filter clogging integrated into the control automation system.

[0025] The objective of the claimed invention is to create a unit for cleaning liquid media from mechanical impurities, ensuring a continuous filtration process in a fully automatic mode, with minimal losses of contaminated and purified filtered medium, with minimal consumption of flushing liquid and minimal volume of contaminated effluents, which ensures economic efficiency and environmental safety of the filtration process.

[0026] The essence of the claimed technical solution is expressed in the following set of essential features, sufficient to solve the technical problem indicated by the applicant and to obtain the technical result provided by the invention.

[0027] According to the invention, a device for cleaning liquid media from mechanical impurities, including a vertically oriented housing with a bottom and a cover, a filter element installed inside the housing coaxially with its longitudinal axis, and along the length of the filter element there is an element for feeding a flushing liquid, installed with the possibility of moving along it, wherein at one end of the element for feeding the flushing liquid there is a high-pressure nozzle, and at the other end the element for feeding the flushing liquid is connected to a high-pressure pump through a hose for feeding the flushing liquid, characterized in that the filter element divides the volume of the housing into "dirty" and "clean" zones, the element for feeding the flushing liquid is connected to a device for its linear reciprocating movement, at the end of the element for feeding the flushing liquid there is fixed one or more flushing nozzles, fixed with the possibility of rotation around the axis of the element for feeding the flushing liquid,the internal cavity of which communicates with the outlet of the high-pressure pump, in addition, the filter housing is provided with inlet and outlet pipes with means for determining the degree of filter clogging, and the filter housing is equipped with a system for minimizing losses of the filtered medium, which is a mechanism for returning the contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element for repeated subsequent filtration and a mechanism for returning the cleaned filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element for feeding the filtered medium into the collector, and a system for removing the washing liquid from the filter housing during washing of the filter element from the "clean" and from the "dirty" zones into the drainage collector.

[0028] In addition, the claimed technical solution is characterized by the presence of a number of additional optional features, namely: - means for determining the degree of filter clogging can be made in the form of pressure transducers;

[0029] - the mechanism for returning contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element can be equipped with an auxiliary tank;

[0030] - an auxiliary tank used in the mechanism for returning contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element may be equipped with a device for unloading settling impurities of large fractions;

[0031] - the mechanism for returning contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element can be equipped with an auxiliary pump;

[0032] - the mechanism for returning contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element may be equipped with means for using pressurization of the contaminated filtered medium with compressed air or other compressed gas;

[0033] - the mechanism for returning contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element may be equipped with a similar filter connected in parallel, to the input of which a pipeline is connected for supplying contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element;

[0034] - the mechanism for returning contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element may be equipped with a parallel-connected filter of a different design, to the input of which a pipeline is connected for supplying contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element;

[0035] - rotation of the flushing nozzle relative to the axis of the flushing liquid supply element can be achieved by means of the jet thrust of the flowing jet of flushing liquid;

[0036] - rotation of the flushing nozzle relative to the axis of the flushing liquid supply element can be implemented by means of an auxiliary drive; - rotation of the flushing nozzles relative to the axis of the flushing liquid supply element can be implemented by a pair of opposed nozzles;

[0037] - the mechanism for returning the purified filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element, for feeding the filtered medium into the collector can be equipped with an auxiliary pump;

[0038] - the flow of the filtered medium at the time of washing the filter element can be directed to another parallel-connected filter of a similar design to ensure the continuity of the filtration process;

[0039] - the flow of the filtered medium at the time of washing the filter element can be directed to another parallel-connected filter of a different design to ensure the continuity of the filtration process.

[0040] The declared set of essential features ensures the achievement of a technical result, which consists of the following:

[0041] - flushing requires a small volume of water, and the volume of wastewater generated is small;

[0042] - the filtration system flows are directed in such a way that, unlike backwash filters, the filtered medium is preserved (returned to the process) and its disposal does not require;

[0043] - washing takes little time and ensures complete regeneration of the filter element, and high pressure of 150-200 bar allows you to clean the filter element from any contaminants, even with a filtration rating of 2 microns, without damaging it;

[0044] - flushing is performed in a fully automated mode, eliminating personnel contact with the filtered medium, which may contain harmful substances.

[0045] - it is possible to connect filters with automatic control in parallel, this allows you to redirect the flow of the filtered medium during the washing of the filter element to a parallel-connected filter in automatic mode, which ensures the continuity of the filtration process.

[0046] The essence of the claimed technical solution is explained by the drawing Fig. 1, which shows the functional diagram of the claimed installation. In the functional diagram Fig. 1, the following items are designated:

[0047] 1 - inlet valve for contaminated filtered medium, 2 - outlet valve for clean filtered medium, 3 - outlet valve for contaminated filtered medium for recycle, 4 - valve for complete emptying of the "clean" zone of the filter, 5 - drain valve, 6 - drain valve for the "clean" zone of the filter during flushing, 7 - isolation valve for flushing nozzles, 8 - filter housing (pressure vessel), 9 - filter element, 10 - "clean" zone of the filter, 11 - "dirty" zone of the filter, 12 - pressure transducers, 13 - hollow rod for supplying flushing water, 14 - linear displacement device, 15 - flushing nozzles, 16 - high-pressure pump, 17 - auxiliary tank, 18 - large sediment unloading sluice, 19 - pump for pumping settled medium, 20 - check valve.

[0048] The declared installation for cleaning liquid filtered medium from mechanical impurities operates as follows:

[0049] Filtration. Tap 1 of the contaminated filtered medium inlet and tap 2 of the purified filtered medium outlet are opened. The contaminated filtered medium enters the "dirty" zone of filter 1 1 . Passing through the mesh of the metal filter element 9, the purified filtered medium enters the "clean" zone of filter 10, while the mechanical impurities present in the filtered medium are retained on the walls of filter element 9. Upon reaching the preset pressure drop, determined by the readings of pressure transducers 12, the automatic control system starts the filtration cycle stop and the filter housing emptying cycle to wash the filter element (not shown in the drawing).

[0050] Emptying the filter housing before washing the filter element.

[0051] Taps 1 and 2 are closed. Taps 3 for recirculation of the filtered medium are opened (depending on the design of the unit and the type of its connection, the contaminated filtered medium is returned to the original tank, or to the collector of the contaminated filtered medium, or is drained into the auxiliary tank 17, or is directed to the input of the parallel-connected filter) and the tap 4 for complete emptying of the "clean" zone. A certain preset time is waited for to ensure complete emptying of the filter housing 8. Due to the presence of the recirculation branch pipe and the drain branch pipe of the "clean" zone, there is no need to empty the filter housing into the sewer, there is no loss of the filtered medium.

[0052] This is achieved by using an auxiliary storage tank 17, a sluice for unloading large deposits 18, a pump 19 for pumping the settled medium from the auxiliary tank and a check valve 20 to prevent the reverse flow of the medium.

[0053] Washing the filter element. Close taps 3 and 4. Open tap 7 for isolating the wash nozzles. Also open drain tap 5 and tap 6 for emptying the "clean" zone during wash. Linear displacement device 14 begins to lower wash water supply rod 13 down into filter housing 8. As soon as wash nozzles 15 are at the level of the upper end of filter element 9, high pressure pump 16 starts. The jet of wash water makes wash nozzles spin around the axis of rod 13, linear displacement device 14 lowers rod 13 down to the lower end of filter element 9. Thus, effective washing of the filter element is ensured over its entire filtration area. Mechanical impurities trapped by the inner surface of the filter element are knocked down by a stream of water and are carried down by the flow of liquid and then drained into the sewer through open tap 5.Part of the wash water that got into the "clean" zone of filter 10 is carried away from there through open tap 6 and further into the drainage. Then the filtration system returns to its original state and the operating algorithm is repeated. Thanks to such a developed drainage system, there is no need to drain the filtered medium into the sewer, only contaminants diluted with water are drained (the total water consumption for one wash cycle is no more than 30 liters), complete removal of wash water from the filter housing is ensured.

[0054] The installation of the claimed design allows to increase the economic efficiency and environmental safety of various chemical industries, reduce labor costs and eliminate equipment downtime associated with the need for filter regeneration. For example, the integration of the claimed installation into absorption gas cleaning systems with aqueous solutions of alkanolamines will reduce the content of mechanical impurities to the lowest level, quickly increase the economic efficiency of the installations by reducing foaming, and during long-term operation, reduce abrasive wear of the equipment, increase the service life and efficiency of the adsorption carbon filter, reducing the load caused by mechanical impurities, and also reduce the amount of sludge deposits in heat exchangers and other devices, which in turn will lead to a decrease in corrosive wear of the installations and a decrease in thermal destruction of alkanolamines in local overheating zones.In comparison with filtration units of other designs, the use of the declared unit allows to eliminate the loss of expensive and toxic alkanolamine solutions during filtration, allows to eliminate the need for disposal of contaminated disposable filter elements, and allows to minimize the volume of contaminated effluents formed during regeneration (washing) of filter elements.

[0055] The set of essential features of the declared installation that we have declared ensures the achievement of the above-described technical result, which is unattainable using any known analogue and is not obvious to a specialist in this field of technology.

[0056] Industrial application of the declared technical solution is possible using known technical and technological means.

Claims

CLAUSE OF INVENTION 1. An installation for cleaning liquid media from mechanical impurities, including a vertically oriented housing with a cover, a filter element installed inside the housing coaxially with its longitudinal axis, and along the length of the filter element there is an element for feeding a flushing liquid, installed with the possibility of moving along it, wherein at one end of the element for feeding the flushing liquid there is a high-pressure nozzle, and at the other end the element for feeding the flushing liquid is connected to a high-pressure pump through a hose for feeding the flushing liquid, characterized in that the filter element divides the volume of the housing into "dirty" and "clean" zones, the element for feeding the flushing liquid is coupled with a device for its linear reciprocating movement, at the end of the element for feeding the flushing liquid there is fixed one or more flushing nozzles, fixed with the possibility of rotation around the axis of the element for feeding the flushing liquid,the internal cavity of which communicates with the outlet of the high-pressure pump, in addition, the filter housing is provided with inlet and outlet pipes with means for determining the degree of filter clogging, and the filter housing is equipped with a system for minimizing losses of the filtered medium, which is a mechanism for returning contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element for repeated subsequent filtration and a mechanism for returning cleaned filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element for feeding the filtered medium to the collector, and a system for removing flushing liquid from the filter housing during washing of the filter element from the "clean" and from the "dirty" zones into the drainage collector.

2. The installation according to item 1, characterized in that the means for determining the degree of filter clogging are made in the form of pressure transducers.

3. The installation according to item 1, characterized in that the mechanism for returning contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element is equipped with an auxiliary container.

4. The installation according to paragraph 3, characterized in that the auxiliary container used in the mechanism for returning contaminated filtered medium remaining in The filter housing after stopping the filtration process before washing the filter element is equipped with a device for unloading settling impurities of large fractions.

5. The installation according to item 1, characterized in that the mechanism for returning contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element is equipped with an auxiliary pump.

6. The installation according to item 1, characterized in that the mechanism for returning contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element is equipped with means for using pressurization of the contaminated filtered medium with compressed air or other compressed gas.

7. The installation according to item 1, characterized in that the mechanism for returning contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element is equipped with a similar filter connected in parallel, to the input of which a pipeline is connected for supplying contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element.

8. The installation according to item 1, characterized in that the mechanism for returning contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element is equipped with a parallel-connected filter of a different design, to the input of which a pipeline is connected for supplying contaminated filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element.

9. The installation according to item 1, characterized in that the rotation of the flushing nozzle relative to the axis of the flushing liquid supply element is realized due to the jet thrust of the flowing jet of flushing liquid.

10. The installation according to item 1, characterized in that the rotation of the flushing nozzle relative to the axis of the flushing liquid supply element is realized by means of an auxiliary drive.

11. The installation according to item 1, characterized in that the rotation of the flushing nozzles relative to the axis of the flushing liquid supply element is realized by a pair of opposing nozzles.

12. The installation according to item 1, characterized in that the mechanism for returning the purified filtered medium remaining in the filter housing after stopping the filtration process before washing the filter element, for feeding the filtered medium into the collector, is equipped with an auxiliary pump.

13. The installation according to item 1, characterized in that the flow of the filtered medium at the time of washing the filter element is directed to another parallel-connected filter of a similar design to ensure the continuity of the filtration process.

14. The installation according to item 1, characterized in that the flow of the filtered medium at the time of washing the filter element is directed to another parallel-connected filter of a different design to ensure the continuity of the filtration process.

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