CN115253442A

CN115253442A - Three-stage filter

Info

Publication number: CN115253442A
Application number: CN202210934920.5A
Authority: CN
Inventors: 陈彩霞; 李辉; 陆克槨; 单春峰; 李子圣
Original assignee: Beijing Brunt Technology Co ltd
Current assignee: Beijing Brunt Technology Co ltd
Priority date: 2022-08-05
Filing date: 2022-08-05
Publication date: 2022-11-01

Abstract

The invention provides a three-stage filter, which is suitable for a multi-stage filter-pressing membrane-breaking mercury purification device under the normal temperature condition and comprises a three-stage upper inlet seat, a three-stage upper flange seat, a three-stage filter pipe, a three-stage lower flange seat and a three-stage lower outlet seat which are sequentially connected from top to bottom; a third O-shaped sealing ring is arranged between the third-stage upper inlet seat and the third-stage upper flange seat, and the upper part of the third O-shaped sealing ring is abutted against the lower surface of the third-stage upper inlet seat; the third-level lower outlet seat is in a bowl shape, a third-level filter discharge port with an interface is arranged at the lower part of the third-level lower outlet seat, a fourth O-shaped sealing ring is arranged between the third-level lower outlet seat and the third-level lower flange seat, and the upper part of the fourth O-shaped sealing ring is abutted to the lower surface of the third-level lower flange seat. The three-stage filter has reliable performance, safety, environmental protection and high environmental applicability, can realize on-site timely environmental protection treatment by a mercury laboratory, and reduces the risk of secondary pollution diffusion transfer.

Description

Three-stage filter

Technical Field

The invention belongs to the technical field of mercury purification, and particularly relates to a three-stage filter, which is suitable for a multi-stage filter-pressing membrane-breaking mercury purification device and method under a normal temperature condition.

Background

Mercury is a silvery white liquid metal, often called "mercury", and is the only metal that naturally exists in a liquid state at room temperature. The mercury has high density (13.6 g/cm 3), low melting point (38.87 deg.C), and boiling point of 357 deg.C, and is useful in chemical industry, electrical equipment, instrument, medicine, metallurgy, military industry, and new technology.

The rock core mercury intrusion method is widely used in the fields of laboratories of various oil fields in China and the industrial protection research field of energy geological nuclei, is used for detecting the porosity of concrete, mortar and the like in material science and engineering professional laboratories, is used for representing indexes such as air holes in the concrete and the like, and needs to consume a large amount of mercury when detecting a rock core sample every year, particularly the rock core mercury intrusion method is the most reliable method for determining the rock pore structure and knowing the stratum characteristics in the current geological laboratories, and has no better alternative detection means at present. The purity of the polluted mercury which is generated after the detection test and is contacted with the detection medium is reduced, the polluted mercury cannot be used continuously, meanwhile, part of mercury enters the hole of the rock core to form mercury-containing rock core toxic dangerous waste, if the polluted mercury cannot be timely and environmentally treated and purified, a large amount of storage has huge environmental protection safety risks, and even normal experiment development is influenced by the control limit of the total quantity of the taken mercury, so that the mercury in the mercury-containing rock core needs to be timely extracted and reused, the purity of the generated mercury is generally lower than 98 percent and lower than the use standard, and the low-coarse mercury or the polluted mercury is purified and reused, so that the method has economic value, and can be recycled and reduce the total quantity.

At present, mercury purification methods mainly comprise a high-temperature distillation method, a chemical-electrochemical method, a cyclone separation purification method, a high-temperature atomic steam + composite purification method and the like. The disadvantages of high-temperature distillation purification and high-temperature atomic steam + composite purification are that the danger of producing highly toxic mercury vapor is great; the chemical-electrochemical method has the problems that secondary pollution liquid is difficult to treat in an environment-friendly way and secondary pollution chains are retreated; besides the prior purification purity, the application scene of the cyclone separation purification equipment is not suitable for the small-scale and space-limited on-site purification scene in a laboratory.

Disclosure of Invention

Based on the technical problems in the prior art, the invention provides a three-stage filter, which is suitable for a multi-stage filter-pressing membrane-breaking mercury purification device and method under the normal temperature condition.

According to the technical scheme, the invention provides a three-stage filter, which is suitable for a multi-stage filter-pressing membrane-breaking mercury purification device under the normal temperature condition and comprises a three-stage upper inlet seat, a three-stage upper flange seat, a three-stage filter pipe, a three-stage lower flange seat and a three-stage lower outlet seat which are sequentially connected from top to bottom; a third O-shaped sealing ring is arranged between the third-stage upper inlet seat and the third-stage upper flange seat, and the upper part of the third O-shaped sealing ring is abutted against the lower surface of the third-stage upper inlet seat; the third-level lower outlet seat is bowl-shaped, a third-level filter discharge port with an interface is arranged at the lower part of the third-level lower outlet seat, a fourth O-shaped sealing ring is arranged between the third-level lower outlet seat and the third-level lower flange seat, and the upper part of the fourth O-shaped sealing ring is abutted to the lower surface of the third-level lower flange seat.

Preferably, an annular accommodating groove is formed in the upper surface of the third-stage upper flange seat, and the third O-shaped sealing ring is embedded in the accommodating groove. The inlet seat at the upper part of the third stage is in an inverted bowl shape, the upper part of the inlet seat at the upper part of the third stage is provided with a feed port of the third stage filter and an outlet at the upper part of the third stage filter which are communicated, and the feed port and the outlet are both provided with interfaces for connection.

More preferably, the third-stage upper inlet seat is connected with the third-stage upper flange seat through a bolt, and the bottom of the third-stage upper flange seat is provided with a through hole and communicated with the upper end of the third-stage filter pipe. Annular holding tank has been seted up at tertiary lower part export seat upper surface, and fourth O type sealing washer embedding sets up in this holding tank.

Furthermore, a plurality of through holes which are penetrated from top to bottom are correspondingly formed in the positions, close to the edge, of the three-level upper flange seat and the three-level lower flange seat, a plurality of double-end studs penetrate into the through holes, and the two ends of each double-end stud are fixed through matched nuts, so that the three-level filter pipe is clamped and fixed between the three-level upper flange seat and the three-level lower flange seat. The bottom of the third-level upper flange seat and the top of the third-level lower flange seat are both provided with grooves or flanges for positioning, and two ends of the third-level filter pipe are respectively embedded into the grooves or the flanges.

Preferably, the third-stage filter pipe comprises a third-stage hollow filter column which is communicated up and down, and a plurality of layers of filter screens of the third-stage filter are distributed in the third-stage hollow filter column along the length direction. More preferably, the filter screen of the three-stage filter of each layer is clamped and fixed by an extrusion ring and an inner column, and the extrusion ring and the inner column are both hollow cylinders.

More preferably, the top of the third-stage lower flange seat is provided with an annular flange, and an annular accommodating groove is formed in the inner side surface of the third-stage lower flange seat, and a lower O-shaped sealing ring is embedded in the annular accommodating groove.

Compared with the prior art, the three-stage filter has the following beneficial technical effects:

1. the three-stage filter has reliable performance, safety, environmental protection and high environmental applicability, can realize on-site timely environmental protection treatment by a mercury laboratory, and reduces the risk of secondary pollution diffusion transfer; and the absolute amount of mercury in a laboratory can be reduced, the recycling is promoted, good economic benefits and environmental protection social benefits are achieved, and the requirement of environmental protection policy encouragement is met.

2. The coarse mercury vibrating screen secondary filter and the tertiary fine filter developed and designed by the scheme of the tertiary filter are designed by adopting similar cone + cylinder combined inner cavities at the upper end and the lower end, the middle is connected with a secondary or tertiary filter tube structure in a combined manner by adopting a reducing hole, the structure is a dumbbell-shaped structure with the wide upper end and the narrow middle, the friction and constant flow variable cross section tubule acceleration function and the front-back differential pressure expansion effect of a Venturi tube narrow tube throttling interface can be realized by the secondary filter, and the friction and mixing filtering effect is enhanced mainly according to the basic principle of hydromechanics (the conservation law of mechanical energy, namely Bernoulli equation and conservation law of mass).

3. The three-stage filter structure design of the invention not only applies the Venturi tube effect, but also adopts three layers of screens which gradually reduce meshes (namely increase the mesh number of the screens), so as to form more micro variable flow cross section mesh effects, and microsphere particle high-interface tension microsphere liquid drops containing dust and oxide films are further extruded and deformed and rubbed when passing through mesh holes (the basic principle is based on Laplace equation), so that the filtering effect is further improved.

4. According to the scheme, the pre-filtering column, the secondary filter and the tertiary filter are adopted to form a multi-stage screen mesh number increasing filtering combination, a pressure extrusion continuous membrane breaking optimization functional structural system is constructed, and the properties of normal-temperature high-density liquid and high specific surface tension of mercury and the multi-stage screen extrusion friction membrane breaking effect are fully utilized.

Drawings

FIG. 1 is a schematic structural diagram of a multistage filter-pressing membrane-breaking mercury purification device under normal temperature conditions.

FIG. 2 is a schematic cross-sectional view of a prefilter column of the present invention.

FIG. 3A is a schematic view of the assembly of the parts of the two-stage filter of the present invention.

FIG. 3B is a schematic cross-sectional view of a two-stage filter according to the present invention.

Fig. 4A is a schematic cross-sectional structure of a three-stage filter of the present invention.

Fig. 4B is a partially enlarged view of a portion of the tertiary filter tube of fig. 4A.

FIG. 5 is a schematic structural diagram of a transmittance detection module and a detection tube according to the present invention.

Fig. 6 is a schematic structural view of a mercury removal filter preferably used in the deionized water circulation mercury removal filter and/or the sewage discharge mercury removal filter according to the present invention.

FIG. 7 is a line graph of experimental data showing the difference P1-P2 between the head pressures of the inlet pressure sensor and the intermediate pressure sensor as a function of the pressure filtration time Tosc for the two-stage filter in accordance with one embodiment of the present invention.

Description of reference numerals in the drawings:

1. the nitrogen source inlet controls the electromagnetic valve; 2. an outlet electromagnetic valve of the buffer tank; 3. a gas-liquid vent electromagnetic valve; 4. A crude mercury feeding control electromagnetic valve; 5. flow isolating electromagnetic valves; 6. a coarse mercury outlet solenoid valve; 7. an outlet electromagnetic valve of the pre-filtering column; 8. a filtering and flushing bypass electromagnetic valve; 9. the secondary filter isolates the electromagnetic valve; 10. a secondary filter flushing solenoid valve; 11. an inlet electromagnetic valve of the tertiary filter; 12. cleaning the electromagnetic valve at the top of the tertiary filter; 13. a mercury outlet electromagnetic valve of the tertiary filter; 14. the electromagnetic valve is isolated at the top of the detection pipe; 15. an outlet electromagnetic valve of the liquid medicine pump; 16. an outlet electromagnetic valve of a deionized water circulating pump; 17. a fine mercury filling control electromagnetic valve; 18. a de-ionized water return inlet electromagnetic valve; 19. a discharge cycle switching solenoid valve; 20. a sewage discharge electromagnetic valve;

21. pre-filtering the column; 22. a secondary filter; 23. a third filter; 24. a deionized water circulating mercury removal filter; 25. a mercury removing filter for discharging sewage;

26. a sample injection pressurizing pump; 27. a liquid medicine pump; 28. a deionized water circulating pump; 29. a nitrogen generator; 30. a vortex oscillator; 31. an inlet pressure sensor; 32. an intermediate pressure sensor; 33. an outlet pressure sensor;

34. a low pressure nitrogen buffer tank; 35. a coarse mercury bottle; 36. a fine mercury collecting bottle; 37. a detection tube; 38. a purified liquid medicine bottle; 39. a deionized water bottle; 40. an outlet sewage bottle; 41. a light transmittance detection module;

211. a glass fiber part; 212. a quartz glass ball section; 213. an outlet end cover of the pre-filtering column; 214. a pre-filter column filter tube; 215. an inlet end cover of the pre-filtering column;

2201. a secondary top helical end cap; 2202. a second-stage vibrating screen friction cavity; 2203. a second-stage intermediate reducing pipe; 2204. A secondary coarse mercury receiving cavity; 2205. a first-stage screen of a second-stage filter; 2206. a first O-ring seal; 2207. a second stage filter screen of the second stage filter; 2208. a second O-ring seal; 2209. a feed inlet of the secondary filter; 2210. a secondary filter drain outlet; 2211. a discharge port of the secondary filter;

2301. a feed inlet of the tertiary filter; 2302. a tertiary upper inlet seat; 2303. a third-level upper flange seat; 2304. A third O-ring seal; 2305. a stud; 2306. a third-level lower flange seat; 2307. a fourth O-shaped sealing ring; 2308. a tertiary lower outlet seat; 2309. a discharge hole of the third-stage filter; 2310. an upper seal ring; 2311. a three-stage hollow filter column; 2312. an O-shaped sealing ring at the inner side of the upper part; 2313. an extrusion ring; 2314. a first inner column; 2315. a gap portion O-shaped seal ring; 2316. a second inner column; 2317. a lower O-shaped seal ring; 2318. an O-shaped sealing ring of the insertion part; 2319. a stainless steel mesh sheet; 2320. a filter screen of the third-stage filter; 2321. an upper outlet of the tertiary filter;

4101. a light transmittance detector; 4102. a stepping motor; 4103. a bracket is fixed at the upper end of the detection tube; 4104. a fixed bracket is arranged at the lower end of the detection tube; 4105. a linear guide rail; 4106. a clamp plate is arranged on the detector; 371. detecting an upper interface of the tube; 372. detecting a lower pipe interface;

241. sealing an end cover at the inlet of the mercury removal filter; 242. mercury removal resin; 243. a mercury removal filter tube; 244. and sealing the end cover at the outlet of the mercury removal filter.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention provides a three-stage filter, which is suitable for a multi-stage filter-pressing membrane-breaking mercury purification device under the normal temperature condition and comprises a three-stage upper inlet seat, a three-stage upper flange seat, a three-stage filter pipe, a three-stage lower flange seat and a three-stage lower outlet seat which are sequentially connected from top to bottom; a third O-shaped sealing ring is arranged between the third-stage upper inlet seat and the third-stage upper flange seat, and the upper part of the third O-shaped sealing ring is abutted against the lower surface of the third-stage upper inlet seat; the third-level lower outlet seat is bowl-shaped, a third-level filter discharge port with an interface is arranged at the lower part of the third-level lower outlet seat, a fourth O-shaped sealing ring is arranged between the third-level lower outlet seat and the third-level lower flange seat, and the upper part of the fourth O-shaped sealing ring is abutted to the lower surface of the third-level lower flange seat.

Preferably, an annular accommodating groove is formed in the upper surface of the third-stage upper flange seat, and the third O-ring is embedded in the accommodating groove. The inlet seat at the upper part of the third stage is in an inverted bowl shape, the upper part of the inlet seat at the upper part of the third stage is provided with a feed port of the third stage filter and an outlet at the upper part of the third stage filter which are communicated, and the feed port and the outlet are both provided with interfaces for connection.

The three-stage filter is suitable for a multi-stage filter-pressing membrane-breaking mercury purification process under the normal temperature condition, and the technical principle of the process is as follows: compared with the traditional high-temperature distillation purification method, the chemical-electrochemical and other traditional methods, the technical scheme of the invention has the advantages of safer personnel operation environment and less harm of secondary diffusion transfer of environmental pollution, and is suitable for popularization and utilization in small-scale scenes of professional laboratories in a plurality of professional fields of mercury utilization. The multi-stage filter-pressing membrane-breaking mercury purification device and method provided by the invention ensure that the discharged sewage meets the relevant environmental protection standards. The method adopts an automatic and miniaturized integrated process flow for manufacturing, improves the applicability of the application environment, realizes the on-site timely environment-friendly treatment by a mercury laboratory, and reduces the risk of secondary pollution diffusion transfer.

In the crude mercury with impurities, the mercury and most of the media have a characteristic of high interfacial tension, thereby forming an oxide film or a dust interfacial film on the outer layer of the mercury. For example, mercury soot is a loose substance formed in the mercury refining process and composed of small mercury beads, fine mineral dust, arsenic antimony oxide, hydrocarbon, water, mercury sulfide, mercury sulfate and the like, and mercury soot structure also exists in the polluted mercury detected by mercury overpressure method. The mercury beads are surrounded by a tough film and dispersed in the medium, so that the film needs to be broken during the physical purification treatment to release mercury and polymerize the mercury together, which is called "membrane rupture". For example, mercury is recovered by washing with water to remove most of the soot and separating the mercury which is easily polymerized, and then placing into a mercury soot machine to break the film on the surface of mercury under mechanical compression to polymerize the mercury.

The multi-stage filter-pressing membrane-breaking mercury purification device under the normal temperature condition is explained below by combining the attached drawings. Referring to fig. 1, the multi-stage filter-press membrane-breaking mercury purification device at normal temperature of the present invention includes an automatic process operation and quality control electric part, a multi-stage filtration purification part, a gas-liquid pressure power part, and a gas-liquid storage part, wherein:

the automatic flow operation and quality control electric part is used for identifying and judging whether the critical conditions of the electrical elements such as a pump, an electromagnetic valve and the like in the multistage filter-pressing membrane-breaking mercury purification device at normal temperature are met or not, and the flow path conversion, the operation sequence control, the sensor data acquisition, the subprogram skip and the quality control index are carried out so as to realize the automatic operation of the treatment process of the device;

the multistage filtering and purifying part is used for performing graded fine filtering and purification on coarse mechanical impurities, fine dust after mercury soot breaking and a metal oxide film in the multistage filter-pressing membrane-breaking mercury purifying device under the normal temperature condition so as to obtain recyclable refined mercury which meets the quality standard requirement of a mercury pressing experiment;

the gas-liquid pressure power part is used for providing drive and pressure for gas-liquid (nitrogen, deionized water and mercury) flowing, circulating, membrane breaking, flushing and purifying in the multistage filter-pressing membrane-breaking mercury purification device at normal temperature;

and the gas-liquid storage part is used for the substation storage of driving gas, purifying advanced crude mercury, stage-filtering mercury of a secondary filter and a tertiary filter, filtering qualified fine mercury, deionizing circulating water and process flushing sewage in the multistage filter-pressing membrane-breaking mercury purification device under the normal temperature condition.

Further, the automatic process operation and quality control electrical part includes a nitrogen source inlet control solenoid valve 1 (normally closed type), a buffer tank outlet solenoid valve 2 (normally closed type), a gas-liquid vent solenoid valve 3 (normally closed type), a coarse mercury charging control solenoid valve 4 (normally closed type), a process isolation solenoid valve 5 (normally open type), a coarse mercury outlet solenoid valve 6 (normally open type), a pre-filter column outlet solenoid valve 7 (normally open type), a filtration flushing bypass solenoid valve 8 (normally open type), a secondary filter isolation solenoid valve 9 (normally open type), a secondary filter flushing solenoid valve 10 (normally open type), a tertiary filter inlet solenoid valve 11 (normally open type), a tertiary filter top cleaning solenoid valve 12 (normally open type), a tertiary filter mercury outlet solenoid valve 13 (normally closed type), a light transmittance detection module 41, a detection tube top isolation solenoid valve 14 (normally closed type), a closed type liquid pump outlet solenoid valve 15 (normally closed type), a deionized water circulation pump outlet solenoid valve 16 (normally closed type), a fine mercury control solenoid valve 17 (normally open type), a deionized water return liquid inlet solenoid valve 18 (normally open type), a discharge circulation conversion solenoid valve 19 (normally closed type), and a wastewater discharge type solenoid valve 20 (normally closed type); and control circuits and devices connected with the components, such as a PLC (programmable logic controller) electric automation control system (including PLC control software and the like) and a touch screen for displaying and operating.

The multi-stage filtration purification part comprises a pre-filtration column 21, a secondary filter 22 (a coarse mercury vibration screening filter), a tertiary filter 23 (a fine static filter or a precise filter), a deionized water circulation mercury removal filter 24 and a sewage discharge mercury removal filter 25.

The gas-liquid pressure power part comprises a sample injection pressurizing pump 26, a liquid medicine pump 27, a deionized water circulating pump 28 (preferably, the three pumps are all peristaltic pumps), a nitrogen generator 29, a vortex oscillator 30, an inlet pressure sensor 31, an intermediate pressure sensor 32 and an outlet pressure sensor 33.

The gas-liquid storage part comprises a low-pressure nitrogen buffer tank 34, a coarse mercury bottle 35, a fine mercury collecting bottle 36, a detection tube 37 (which is a quartz glass tube and is matched with a light transmittance detection module 41 to realize gas-water mercury detection), a purified liquid medicine bottle 38, a deionized water bottle 39 and an outlet sewage bottle 40.

In an embodiment, the multistage filter-pressing membrane-breaking mercury purification device under the normal temperature condition comprises an air pressure driving unit, a crude mercury bottle 35, a pre-filter column 21, a secondary filter 22, a tertiary filter 23 and a fine mercury collecting bottle 36 which are sequentially connected through a pipeline assembly.

The pneumatic driving unit is used for filling mercury to be filtered in the upper chambers of the secondary filter and the tertiary filter, pressurizing and filtering the lower chambers of the secondary filter and the tertiary filter and flushing a flow pipeline;

a coarse mercury bottle 35 for storing the coarse mercury to be treated or quantitatively storing the polluted mercury;

the pre-filtering column 21 is used for primary filtering of coarse mechanical impurities in coarse mercury or polluted mercury, and pollution and flow blockage to a secondary filter are reduced;

a secondary filter 22 for filtering fine dust impurities and realizing filter pressing and mechanical shock comprehensive membrane breaking of the mercury soot mixture;

the third-stage filter 23 is used for further fine filtration of the second-stage filtered mercury, oxidation film dissolution, reverse flushing circulation of deionized water buoyancy and other deep purification;

and the fine mercury collecting bottle 36 is used for collecting and storing fine mercury which is sequentially purified step by step through pre-filtering column filtration, secondary filter filtration, tertiary filter filtration, deionized water reverse buoyancy flushing and the like and then reaches the mercury standard for mercury pressing experiments.

The air pressure driving unit comprises a nitrogen generator 29 and a nitrogen buffer tank 34, the output end of the nitrogen generator 29 is connected with the input end of the nitrogen buffer tank 34 through a nitrogen source electromagnetic valve 1, and an inlet pressure sensor 31 is arranged on a pipeline between the nitrogen source electromagnetic valve 1 and the nitrogen buffer tank 34; the output end of the nitrogen buffer tank 34 is connected with the input end of the thick mercury bottle 35 through the buffer tank outlet electromagnetic valve 2; an external vent pipe is further arranged on the pipeline between the nitrogen buffer tank 34 and the crude mercury bottle 35 in a branching manner, and a gas-liquid vent electromagnetic valve 3 is arranged in the external vent pipe.

The input end of the thick mercury bottle 35 is further connected with a thick mercury feeding unit, the thick mercury feeding unit comprises a sample feeding pipe, the input end of the sample feeding pipe is used for being connected with an external thick mercury container for storing mercury to be purified, the output end of the sample feeding pipe is connected with a sample feeding pressurizing pump 26, and the output end of the sample feeding pressurizing pump 26 is connected with the feed inlet of the thick mercury bottle 35 through a thick mercury feeding electromagnetic valve 4.

The output end of the coarse mercury bottle 35 is connected with the input end of the pre-filter column 21 through a coarse mercury outlet electromagnetic valve 6. The output end of the pre-filter column 21 is connected with the input end of the secondary filter 22 through the pre-filter column outlet electromagnetic valve 7.

The secondary filter 22 is provided with a secondary upper cavity, a secondary filter pipe and a secondary lower cavity which are sequentially communicated from top to bottom, a discharge hole at the bottom of the secondary lower cavity is connected with the input end of the tertiary filter 23 through a tertiary filter inlet electromagnetic valve 11, and a middle pressure sensor 32 is arranged on a pipeline between the secondary filter 22 and the tertiary filter inlet electromagnetic valve 11.

The three-stage filter 23 is provided with a three-stage upper cavity, a three-stage filter pipe and a three-stage lower cavity which are sequentially communicated from top to bottom, and a discharge hole at the bottom of the three-stage lower cavity is sequentially connected with a fine mercury collecting bottle 36 through a three-stage filter mercury outlet electromagnetic valve 13 and a fine mercury filling control electromagnetic valve 17.

In another embodiment, the system further comprises a fine mercury standard detection unit, a deionized water washing unit, a dosing unit and a clean pollution discharge unit.

The fine mercury standard-reaching detection unit is used for detecting the cleanliness (light transmittance) of a circulating liquid obtained after fine mercury filtered by the three-stage filter is circularly flushed by deionized water so as to indirectly judge whether mercury subjected to deep filtration treatment by the three-stage filter reaches the standard or not; if the flushing time does not reach the standard, further determining to continue circulating flushing; if the standard is reached, opening a fine mercury bottle filling valve to carry out fine mercury filling;

the deionized water cleaning unit is used for pumping deionized water from a second outlet at the bottom chamber or the top chamber of the secondary filter or the tertiary filter by using a circulating pump, flushing, cleaning and unblocking filter screens and an upper chamber of the secondary filter and the tertiary filter, and guiding sewage into a sewage bottle through a sewage discharge pipeline;

the dosing unit is used for dissolving trace chemical agents in the filtered mercury which still has a metal oxide film after three-stage filtration (preferably physical filtration) so as to improve the purity of the mercury and ensure that the mercury is finally purified to reach the standard;

and the cleaning and sewage discharging unit is used for flushing and back flushing non-pure mercury substances such as impurity, dust and particles generated in the purification processes of pre-filtration, secondary filtration, tertiary filtration, reverse buoyancy circulating flushing and the like, and discharging the non-pure mercury substances into the sewage bottle, and then removing mercury through the mercury removal filter, so that the environment is protected and discharged after reaching the standard.

The accurate mercury detection unit up to standard includes the detection tube 37 and is arranged in detecting the luminousness of fluid luminousness among them and detects module 41, and the lower extreme of detection tube 37 is connected with the pipeline between tertiary filter mercury export solenoid valve 13 and the accurate mercury filling control solenoid valve 17.

The deionized water cleaning unit comprises a deionized water bottle 39, and the output end of the deionized water bottle 39 is connected with the upper end of the detection tube 37 through the deionized water circulating pump 28 and the outlet electromagnetic valve 16 of the deionized water circulating pump in sequence. An outlet pressure sensor 33 is provided on a line between the deionized water circulating pump outlet solenoid valve 16 and the detection pipe 37. The upper cavity of the third level is connected with an upper outlet of a third level filter, and is connected with an input end of a deionized water bottle 39 through a top cleaning electromagnetic valve 12 of the third level filter, a deionized water circulating mercury removing filter 24 and a deionized water return inlet electromagnetic valve 18 in sequence. The pipeline between the deionized water circulating pump outlet electromagnetic valve 16 and the detection pipe 37 is branched and connected with the pipeline between the three-stage filter top cleaning electromagnetic valve 12 and the deionized water circulating mercury-removing filter 24 through the detection pipe top isolation electromagnetic valve 14.

The medicine adding unit comprises a purifying liquid medicine bottle 38, and the output end of the purifying liquid medicine bottle 38 is connected with the upper end of the detection tube 37 sequentially through a liquid medicine pump 27 and a liquid medicine pump outlet electromagnetic valve 15.

The cleaning and sewage discharging unit comprises an outlet sewage bottle 40, a branch pipe is branched on a pipeline between the flow Cheng Geli electromagnetic valve 5 and the crude mercury outlet electromagnetic valve 6 and is connected with the input end of the outlet sewage bottle 40 through a secondary filter isolation electromagnetic valve 9. The output end of the outlet sewage bottle 40 is a sewage discharge pipe, and a sewage discharge mercury removal filter 25 and a sewage discharge electromagnetic valve 20 are arranged in the sewage discharge pipe. A branch line branches off the line between stream Cheng Geli solenoid valve 5 and secondary filter isolation solenoid valve 9 and connects to secondary filter 22 through a filtrate flush bypass solenoid valve 8. The secondary upper chamber of the secondary filter 22 has a drain outlet and is connected to the input of an outlet dirty water bottle 40 via a secondary filter flush solenoid valve 10. A branch pipe is branched from the pipeline between the top cleaning electromagnetic valve 12 of the three-stage filter and the deionized water circulating mercury removing filter 24 and is connected with the input end of the outlet sewage bottle 40 through a discharge circulating conversion electromagnetic valve 19.

The pre-filter column 21 of the present invention is constructed as shown in figure 2, comprises a pre-filtering column outlet end cover 213, a pre-filtering column filtering pipe 214 and a pre-filtering column inlet end cover 215. The pre-filter column filter tube 214 is, for example, a double-threaded quartz glass tube, two ends of the pre-filter column filter tube are respectively connected with the pre-filter column outlet end cover 213 and the pre-filter column inlet end cover 215 in a threaded manner, and the two ends and the pre-filter column inlet end cover 215 together form a space for accommodating a filter structure of the pre-filter column 21, and the filter structure includes two glass fiber portions 211 close to the pre-filter column outlet end cover 213 and the pre-filter column inlet end cover 215 and a quartz glass ball portion 212 located in the middle. Specifically, in a preferred embodiment, the filter structure is a filter layer sequentially packed in a sandwich structure along the filtering direction, i.e. a glass fiber part 211 (high temperature resistant glass fiber) with a front third thickness (length of the pre-filtering column filtering pipe 214), a quartz glass ball part 212 (e.g. 20 mesh quartz glass ball) with a middle third thickness and a glass fiber part 211 (high temperature resistant glass fiber) with a back third thickness, and the glass fiber part 211 and the quartz glass ball part 212 fill the space for accommodating the filter structure. The outlet end cover 213 of the pre-filter column and the inlet end cover 215 of the pre-filter column are both provided with a connector for connection, the connectors penetrate through the inner space and the outer space of the pre-filter column 21, and the pre-filter column 21 is in a sealing structure except for the two connectors. During operation, coarse mercury enters the internal filter structure through the input end of the pre-filter column 21 (the interface of the inlet end cap 215 of the pre-filter column), passes through the three-layer structure of the filter structure layer by layer, and is finally discharged from the output end (the interface of the outlet end cap 213 of the pre-filter column), so as to realize the pre-filter process. The coarse mercury passes through the pre-filter column 21 to filter out most of the particle impurity components (which cannot pass through the gap between the glass fiber part 211 and the quartz glass ball part 212 and are blocked).

The structure of the secondary filter 22 of the present invention is shown in fig. 3A (assembly drawing) and fig. 3B (cross-sectional drawing), and includes a secondary top spiral end cap 2201, a secondary vibrating screen friction cavity 2202, a first O-ring 2206, a secondary filter first-stage screen 2205, a secondary intermediate reducing pipe 2203 (pressurization and acceleration are achieved by a reducing structure), a second O-ring 2208, a secondary filter second-stage filter screen 2207, and a secondary coarse mercury receiving cavity 2204, which are sequentially connected from top to bottom.

The upper part of the second-stage top spiral end cover 2201 is a cover plate, a second-stage filter feeding hole 2209 and a second-stage filter sewage discharge port 2210 which are communicated are arranged on the cover plate side by side, and the second-stage filter feeding hole 2209 and the second-stage filter sewage discharge port 2210 are provided with interfaces for connection. The lower portion of the secondary top helical end cap 2201 is a cylindrical first connection section with external threads. Secondary top helical end cap 2201 is preferably polytetrafluoroethylene.

The upper section of the second-stage vibrating screen friction cavity 2202 is a cylindrical second connecting section with internal threads, and is connected with the first connecting section at the lower part of the second-stage top spiral end cover 2201 in a matching manner. The inner side of the middle section of the second-stage vibrating screen friction cavity 2202 is an inverted frustum-shaped through hole which is wide at the top and narrow at the bottom. The lower section of the second-stage vibrating screen friction cavity 2202 is a cylindrical third connecting section with external threads. The second-stage vibrating screen friction cavity 2202 is preferably made of polytetrafluoroethylene.

The second-stage intermediate reducing pipe 2203 is embedded in the third connecting section of the second-stage vibrating screen friction cavity 2202 in a matching manner, and the bottom end faces of the second-stage vibrating screen friction cavity and the third connecting section are flush. The inner side of the second-stage middle reducing pipe 2203 is an inverted truncated cone-shaped through hole with a wide upper part and a narrow lower part, and a first blocking shoulder is arranged at the opening of the through hole at the upper part. The secondary intermediate diameter reducer 2203 is preferably a metal or quartz glass tubing string and is replaceable.

The first O-ring 2206 (preferably made of silica gel) and the first-stage screen 2205 (preferably made of stainless steel or nylon, 40 mesh) of the second-stage filter are sandwiched between the bottom of the middle section of the second-stage vibrating screen friction cavity 2202 and the first shoulder of the second-stage intermediate reducing pipe 2203.

The upper section of the secondary coarse mercury receiving cavity 2204 is a cylindrical fourth connecting section with internal threads, and is connected with the third connecting section of the secondary vibrating screen friction cavity 2202 in a matching manner. The lower section of the secondary coarse mercury receiving cavity 2204 is cylindrical with a bottom surface. A second shoulder is formed between the upper section and the lower section of the secondary coarse mercury-receiving cavity 2204. The secondary coarse mercury receiving cavity 2204 is preferably made of polytetrafluoroethylene.

A second O-ring 2208 (preferably made of silica gel) and a second-stage filtering screen 2207 (preferably made of stainless steel or nylon and 80-mesh) of the second-stage filter are clamped and fixed between the bottom of the third connecting section of the second-stage vibrating screen friction cavity 2202 and the second stop shoulder of the second-stage coarse mercury receiving cavity 2204.

A secondary filter discharge port 2211 is arranged at the bottom of the lower section of the secondary coarse mercury receiving cavity 2204, and the outward end of the secondary filter discharge port 2211 is a connector for connection.

In one embodiment, the secondary filter 22 is a fully detachable structure, and is integrally formed with a secondary upper cavity, a secondary filter tube and a secondary lower cavity which are sequentially communicated from top to bottom. The second-stage upper cavity is surrounded by a second-stage top spiral end cover 2201, a second-stage vibrating screen friction cavity 2202 and a second-stage filter first-stage screen 2205 and is in a shape formed by a cone, a cylinder and an inverted circular truncated cone from top to bottom. The secondary filter pipe consists of a secondary filter first-stage screen 2205, a secondary intermediate reducing pipe 2203 and a secondary filter screen 2207. The second-stage lower cavity is surrounded by a second-stage filter screen 2207 of the second-stage filter and a second-stage coarse mercury receiving cavity 2204 and is in a shape formed by a cylinder and an inverted cone from top to bottom.

Referring to fig. 1, a vortex oscillator 30 is installed at a lower portion of the secondary filter 22 to oscillate the vortex oscillator.

The operation and principle of the secondary filter 22 is as follows. Coarse mercury is pressed into a cavity at the upper part of the second stage, and a vibrating screen is used for friction rupture of membranes. And then, the pressure is continuously utilized to enable the crude mercury to pass through a first-stage screen 2205 of the secondary filter and a second-stage filter screen 2207 of the secondary filter, filter pressing friction membrane breaking is carried out, meanwhile, a vortex oscillator 30 is utilized to carry out vortex oscillation operation, and during filter pressing membrane breaking filtration, homogenization is fully oscillated so as to obtain a better membrane breaking purification effect. After being filtered by the secondary filter 22, the low-density coarse mercury rich in impurities and oxide films is distributed on the upper part of the secondary filter secondary filtering screen 2207 or is positioned in a secondary upper cavity, and relatively pure high-density mercury is mutually attracted, polymerized and deposited on the bottom layer of the inverted cone at the bottommost part of the secondary lower cavity to form a primary gravity differentiation layering effect.

The structure of the tertiary filter 23 of the present invention is shown in fig. 4A (overall sectional view) and fig. 4B (partial enlarged view of the portion of the tertiary filter tube in fig. 4A), and includes a tertiary upper inlet seat 2302, a tertiary upper flange seat 2303, a tertiary filter tube, a tertiary lower flange seat 2306, and a tertiary lower outlet seat 2308, which are sequentially connected from top to bottom.

The third-stage upper inlet seat 2302 is in an inverted bowl shape, and a third-stage filter feed opening 2301 and a third-stage filter upper outlet 2321 which are communicated with each other are arranged at the upper part of the third-stage upper inlet seat 2302 and are provided with interfaces for connection. Third O-ring 2304 is disposed between third-stage upper inlet seat 2302 and third-stage upper flange seat 2303, specifically, for example, an annular accommodating groove is opened on the upper surface of third-stage upper flange seat 2303, third O-ring 2304 is embedded in the accommodating groove, and the top of third O-ring 2304 is in contact with the lower surface of third-stage upper inlet seat 2302. Tertiary upper inlet seat 2302 is coupled to tertiary upper flange seat 2303, for example, by bolts. The bottom of the third-stage upper flange seat 2303 is provided with a through hole and is communicated with the upper end of the third-stage filter pipe.

Tertiary lower part export seat 2308 is the bowl form, is provided with the tertiary filter discharge gate 2309 that has the interface in tertiary lower part export seat 2308's lower part, is provided with fourth O type sealing washer 2307 between tertiary lower part export seat 2308 and tertiary lower part flange seat 2306, and annular holding tank has been seted up on tertiary lower part export seat 2308 upper surface specifically for example, fourth O type sealing washer 2307 embedding sets up in this holding tank, and the top of fourth O type sealing washer 2307 is inconsistent with tertiary lower part flange seat 2306's lower surface. Third stage lower outlet seats 2308 are connected to third stage lower flange seats 2306, for example by bolts. The upper portion of the third stage lower flange seat 2306 has a through hole and communicates with the lower end of a third stage filter tube in the form of a filter column.

A plurality of through holes which penetrate through from top to bottom are correspondingly formed in the positions, close to the edges, of the three-level upper flange seat 2303 and the three-level lower flange seat 2306, a plurality of double-end studs 2305 penetrate through the through holes, and the two ends of the double-end studs 2305 are fixed by adopting matched nuts, so that the three-level filter pipe is clamped and fixed between the three-level upper flange seat 2303 and the three-level lower flange seat 2306. Furthermore, the bottom of the third-stage upper flange seat 2303 and the top of the third-stage lower flange seat 2306 are both provided with a groove or a flange for positioning, and two ends of the third-stage filter pipe are respectively embedded into the groove or the flange, so that the fixed position of the third-stage filter pipe is ensured.

In a preferred embodiment, the third-stage filtering pipe comprises a third-stage hollow filtering column 2311 (preferably made of quartz glass) which is through from top to bottom. An annular groove is formed at the bottom of the third-stage upper flange seat 2303, the upper end of the third-stage hollow filter column 2311 is embedded into the annular groove, and an upper sealing ring 2310 (preferably a fluororubber sealing ring) is arranged between the third-stage hollow filter column and the third-stage hollow filter column; and an upper inner O-ring 2312 is clamped with the annular groove at the inner side of the upper end of the three-stage hollow filter column 2311.

A plurality of layers of three-stage filter screens 2320 are distributed in the three-stage hollow filter column 2311 along the length direction, for example, three layers are provided, and the three layers are respectively 100 meshes, 150 meshes and 250 meshes from top to bottom. The three-stage filter filtering net 2320 of each layer is clamped and fixed through a pressing ring 2313 and an inner column (preferably made of quartz glass), the pressing ring 2313 and the inner column are both in a hollow cylinder shape, the pressing ring 2313 is provided with a cylindrical wall in a protruding and extending mode at a position close to the inner side face, a blocking shoulder is formed at a position close to the outer side face, the inner column is provided with a cylindrical wall in a protruding and extending mode at a position close to the outer side face, and a blocking shoulder is formed at a position close to the inner side face, so that the two three-stage filter filtering nets 2320 are inserted in a convex-concave mode in a matched mode, and the three-stage filter filtering net 2320 is clamped in the middle. And, an O-ring 2318 of a bayonet portion is interposed between the outer side surface of the pressing ring 2313 and the inner side surface of the inner column. Specifically, for example, as shown in fig. 4B, the uppermost portion is a first extrusion ring in an inverted convex shape, the lower portion of the first extrusion ring is connected to the first inner column 2314 in a fitting manner, the upper portion of the first inner column 2314 is in a concave shape, the lower portion of the first inner column 2314 is in an inverted concave shape, the lower portion of the first inner column is connected to the second extrusion ring in a fitting manner, the lower portion of the second extrusion ring is a second inner column 2316 in an inverted concave shape, and the lowermost portion of the first extrusion ring is connected to the third extrusion ring in a convex shape; thus, the three-layer three-stage filter net 2320 is fixed at a predetermined distance. A gap O-ring 2315 is further provided between the outer side surface of each extrusion ring 2313 and/or inner column and the inner side surface of the tertiary hollow filter column 2311.

The top of tertiary lower flange seat 2306 is provided with annular flange to set up annular holding tank in the inboard face, the embedding has lower part O type sealing washer 2317 in this annular holding tank, and the lower extreme embedding of tertiary hollow filtration post 2311 is in the annular flange at tertiary lower flange seat 2306 top, and the side is inconsistent with lower part O type sealing washer 2317. A stainless steel mesh sheet 2319 (with a thickness of, for example, 1 mm) is further provided between the bottom surface of the third-stage hollow filter column 2311 and the top surface of the third-stage lower flange seat 2306.

In one embodiment, the third-stage filter 23 is a fully detachable structure and is designed in a combined manner of an upper and a lower double-cone dumbbell-shaped structures, and after assembly, a third-stage upper cavity, a third-stage filter tube and a third-stage lower cavity which are sequentially communicated from top to bottom are integrally formed. The three-level upper cavity is enclosed by a three-level upper inlet seat 2302, a three-level upper flange seat 2303 and a three-level filter screen 2320 at the uppermost end of the three-level filter column, the three-level lower cavity is enclosed by a three-level filter screen 2320 at the lowermost end of the three-level filter column, a three-level lower flange seat 2306 and a three-level lower outlet seat 2308, and the three-level upper cavity and the three-level lower cavity are both double-cone dumbbell-shaped cavities (for example, a right cone, a cylinder and an inverted cone). The structure of the middle part connecting the two double-cone dumbbell-shaped cavities is a three-stage filter tube of a reducing visual filter tube, the three-stage filter tube is provided with a series combination structure of three-stage filter screens 2320 with multiple stages (preferably three or more stages) of different screen meshes increasing gradually (preferably the filter aperture is gradually reduced), so that mercury beads containing impurities or oxide films can be squeezed to deform and rub to break the films by using pressure, the re-polymerization effect is realized, the purpose is to break the mercury soot particles, adsorbed impurities and other aggregate surface adsorption films in crude mercury, and further, the broken pure mercury aggregate units and the impurity water-containing light component system are respectively subjected to layer polymerization, and further, mercury with higher purity and high density and low density mixtures (such as mercury impurities, water and other metal oxide mixtures) are subjected to layer separation extraction and purification and impurity removal.

The operation and principle of the three-stage filter 23 are as follows. Firstly, pressurizing a system flow path, so that the high-density polymerized filtered mercury in the second-stage lower cavity of the second-stage filter 22 is extruded into the third-stage upper cavity of the third-stage filter 23, and the mercury sequentially passes through the multi-layer third-stage filter filtering net 2320 step by step to perform gradually fine membrane-breaking filtration. The mercury liquid of higher purity is finally filtered into the lower tertiary chamber of the tertiary filter 23, during which floating dust, metal oxide, more fine impurities and mercury soot coated particles in the crude mercury are retained on the tertiary filter screen 2320 by the fractional membrane rupture filtration.

In addition, a reverse circulation flushing technology of the buoyancy of the deionized water is adopted in the three-stage filter 23, the deionized water is reversely pumped into a three-stage lower cavity containing the filtered mercury in the three-stage filter 23 from a three-stage filter discharge port 2309 at the bottommost part of the three-stage filter 23 by using a deionized water circulating pump 28, the deionized water can freely and reversely float and flush from bottom to top from the bottom of the three-stage lower cavity without pressure under the buoyancy effect generated by the huge density difference of the mercury, a reverse convection purification effect is formed, and the filtered mercury is further purified.

Furthermore, according to the purification quality requirement of mercury in the tertiary filter 23 and the condition of oxidized impurities, the liquid medicine pump 27 fills a trace amount of purification liquid into the tertiary filter 23 to improve the purification effect. Thus, through the processes of multi-stage extrusion membrane-breaking filtration, reverse buoyancy circulating flushing, impurity removal, purification and purification of trace purification liquid medicine and the like, crude mercury or polluted mercury is purified step by step, and finally, refined mercury with purity meeting the requirement is obtained.

The structure of the transmittance detection module 41 and the detection tube 37 in the invention is shown in fig. 5, the detection tube 37 is a vertically placed quartz glass tube, and both ends of the detection tube are respectively provided with a detection tube upper interface 371 and a detection tube lower interface 372. The light transmittance detection module 41 comprises a vertically arranged linear guide 4105, a detection tube upper end fixing support 4103 is fixedly arranged above the linear guide 4105, and a detection tube lower end fixing support 4104 is fixedly arranged below the linear guide 4105. The upper end fixing holder 4103 and the lower end fixing holder 4104 are fixed (for example, clamped) to the upper and lower ends of the detection tube 37. A detector mounting plate 4106 is slidably connected to the linear guide 4105, a light transmittance detector 4101 is mounted on the detector mounting plate 4106, and the detection position of the light transmittance detector 4101 is opposite to the detection tube 37. Still including being used for driving the step motor 4102 that the detector installation splint 4106 reciprocated to can adjust the detection position of luminousness detector 4101 to high-order detection line U (be close to the detection tube 37 top) or low-order detection line D (be close to the detection tube 37 bottom), realize that gas water mercury three-phase detects.

The operation and principle of the transmittance detection module 41 and the detection tube 37 are as follows. A static gas-water-mercury three-phase detection state interface is established in the detection tube 37, the light transmittance detection module 41 is controlled and adjusted, the light transmittance detector 4101 is used for detecting the water phase cleanliness, namely the light transmittance, in the detection tube 37 at a reasonable detection state position, the deionized water phase light transmittance value when the mercury purity reaches the standard is used as an end condition for confirming that the purification of the circulating filtration mercury reaches the standard, the mercury purification at normal temperature reaches the standard and is recycled, and meanwhile, in the mercury purification process, the external sewage is subjected to mercury removal purification standard reaching treatment to meet the requirement of the environmental protection discharge standard.

On the other hand, luminousness detection module 41 still plays the effect of judging wherein smart mercury's volume at smart mercury filling in-process to control smart mercury filling control solenoid valve 17 and close when smart mercury is about to the earial drainage to finish, guarantee that the water of smart mercury top can not get into smart mercury receiving flask 36. The basic principle is that the light transmittance detection module 41 is adjusted to a low detection line D to emit detection light for detection, and if the mercury column completely shields the detection light, the light transmittance is basically 0; when the transmittance is greater than 50, even close to 100, it indicates that the mercury-water interface is at or below the detection point, and this can be used as a condition for ending the filling action.

In addition, in the preferred embodiment, the volumes of the two-stage upper cavity and the two-stage lower cavity of the two-stage filter 22 and the three-stage upper cavity and the three-stage lower cavity of the three-stage filter 23 are substantially equal to each other, and equal to or slightly larger than the volume of the crude mercury added to the crude mercury bottle 35 in one purification process. Therefore, the crude mercury in the crude mercury bottle 35 is completely filtered to the second-level lower cavity and then completely filtered to the third-level lower cavity, the upper scale mark of the mercury does not exceed the height range of the second-level and third-level lower cavities, and the filtering process can be completed through the pressurization process and the volume-fixing process control. And when the mercury is pressed from the second-stage lower cavity to the third-stage upper cavity, even if the mercury in the third-stage upper cavity is not filtered through the third-stage filter pipe under pressure at the beginning, the mercury does not overflow from the upper outlet 2321 of the third-stage filter during the pressurization driving in the period, and only water, gas or impurity floating dust is extruded from the upper outlet 2321 of the third-stage filter and flows through the top cleaning electromagnetic valve 12 of the third-stage filter, the discharge circulation switching electromagnetic valve 19, the outlet sewage bottle 40, the sewage discharge mercury removal filter 25 and the sewage discharge electromagnetic valve 20 for discharge.

The volume of the detection tube 37 is preferably smaller than the volume of the crude mercury added into the crude mercury bottle 35, so that when the mercury outlet electromagnetic valve 13 of the three-stage filter is opened, the three-stage filter 23 and the detection tube 37 form a communicating vessel structure, the mercury water interface is kept consistent, and the mercury water interface in the lower cavity of the three stages cannot be greatly reduced due to the formation of the communicating vessel because the detection tube 37 is a small-volume thin tube. And, during the fine mercury filling, mercury can be easily and rapidly discharged to the fine mercury collecting bottle 36 under the action of gravity, and it is necessary to ensure that the discharge process is not too rapid, otherwise, controllable filling and detection are not easy to realize. Therefore, the detection tube 37 adopts a small-volume thin tube, and the detection of the mercury-water interface level and the light transmittance of the aqueous solution in the detection tube 37 through the light transmittance detection module 41 is facilitated, so that controllable automatic filling can be realized.

The deionized water circulating mercury removal filter 24 and the sewage discharge mercury removal filter 25 in the invention can adopt mercury removal filters with the same structure, and the structure of the filter is shown in fig. 6, and the filter comprises a hollow mercury removal filter pipe 243 (preferably a double-end threaded quartz glass pipe), wherein mercury removal resin 242 is contained, two ends of the mercury removal filter pipe 243 are respectively provided with a mercury removal filter inlet sealing end cover 241 and a mercury removal filter outlet sealing end cover 244, and the mercury removal filter inlet sealing end cover 241 and the mercury removal filter outlet sealing end cover 244 are both provided with through interfaces, so that wastewater can enter the mercury removal filter pipe from the interface of the mercury removal filter inlet sealing end cover 241, is purified by the mercury removal resin 242, and is discharged from the interface of the mercury removal filter outlet sealing end cover 244. The mercury removal resin is also called ion exchange resin and is used for adsorbing mercury and heavy metals, CH-97 type renewable mercury removal resin is preferably adopted, and the mercury removal resin loaded with mercury after being used can be regenerated by mercury recovery enterprises and then put into use again. In the laboratory mercury purification process, CH-97 type mercury removal resin is filled in a quartz tube to remove and purify trace mercury, so that the environmental protection and safety can be ensured to reach the standard.

The part for controlling the operation of each element in the invention preferably adopts a PLC electric automatic control system, has PLC control software and is connected with a touch screen for operation. The control system realizes the manual operation and the automatic programming operation of 20 electromagnetic valves on a touch screen of a PLC (programmable logic controller) electrical automatic control system, realizes the start and stop control of one nitrogen generator 29, controls the programming and parameter acquisition of three pumps (comprising a sample injection pressurizing pump 26, a liquid medicine pump 27 and a deionized water circulating pump 28) according to the process requirements by utilizing PLC control software (preferably, PLC support software) in the system, and performs the program setting control and the detection data acquisition and storage of detection positions in three pressure sensors (comprising an inlet pressure sensor 31, a middle pressure sensor 32 and an outlet pressure sensor 33) and a light transmittance detection module 41. The PLC control software program is programmed according to the process flow sequence and the operation requirements, and the functions of automatically controlling the whole series of work flows from the pulsating pressure balance adjustment of the nitrogen generator 29, the mercury injection of the coarse mercury bottle 35, the mercury injection and filtration of the secondary filter 22, the mercury injection of the tertiary filter 23, the cleaning and circulating cleaning, the dosing, the recycling cleaning, the mercury cleanliness detection and the automatic sub-packaging of the refined mercury to the end are realized. The relevant specific circuit structure, program software and the like of the PLC electrical automation control system are easy to realize based on the prior art, and are not described in detail herein.

In the multi-stage filter-pressing membrane-breaking mercury purification device under the normal temperature condition, all the following steps can be automatically completed by a PLC (programmable logic controller) electric automatic control system or manually controlled except that manual operation is needed for device assembly, shutdown maintenance and the like. All the mentioned parameters can be input and set in the PLC electrical automation control system, only recommended values are given below, and optimization and adjustment can be specifically carried out according to actual conditions. The detailed working process of the multistage filter-pressing membrane-breaking mercury purification device under the normal temperature condition is as follows:

first, preparation is carried out, and control connection building of each component is carried out according to the layout shown in fig. 1. The connecting pipeline can adopt a Teflon pipeline with the diameter of 6 multiplied by 9mm or the diameter of 5 multiplied by 7mm, the connecting line can adopt a Teflon straight pipe joint or a right-angle joint for connection, the three-line junction can adopt a matched Teflon three-way joint for connection, and the four-line junction can adopt a matched Teflon four-way joint for connection. The operation is not described in detail according to the flow connection specification. And, a cleaning chemical solution (preferably a chemical cleaning solution) is added to the cleaning chemical solution bottle 38, and deionized water is added to the deionized water bottle 39.

Step S1, pressure level checking: the nitrogen generator 29 is correctly preset to start, regulating the output pressure to 0.6MPa. The method comprises the steps of powering off a nitrogen source inlet control electromagnetic valve 1 and a buffer tank outlet electromagnetic valve 2, placing the two valves in a normally closed state, starting an automatic pressure regulating program of a PLC (programmable logic controller) electric automatic control system, collecting pressure P1 measured by an inlet pressure sensor 31, opening the nitrogen source inlet control electromagnetic valve 1 if the pressure P1 is less than or equal to 0.3MPa, communicating the inlet pressure sensor 31 with an output pipeline of a nitrogen generator 29, starting the nitrogen generator 29 to operate, not performing action if the pressure P1 is greater than 0.3MPa, and continuing collection and monitoring until the measured pressure P1 is less than or equal to 0.3MPa; then, as the nitrogen generator 29 pressurizes the low pressure nitrogen buffer tank 34, P1 is gradually increased, and when P1 is greater than or equal to 0.55MPa, the nitrogen source inlet control solenoid valve 1 is closed, and the nitrogen generator 29 is closed. The process is automatically monitored and controlled by a PLC electric automatic control system in the whole process so as to ensure that the working pressure range of the low-pressure nitrogen buffer tank 34 is basically kept between 0.3MPa and 0.55 MPa.

Step S2, adding crude mercury to the crude mercury bottle 35: if the crude mercury is filled manually, the touch screen can be clicked manually to open the gas-liquid vent electromagnetic valve 3, an external vent pipe at the front end of the electromagnetic valve and an external crude mercury container are connected, and the crude mercury in the external waste mercury container is filled into the crude mercury bottle 35 by utilizing a potential difference or a funnel; if the electric filling is adopted, a touch screen 'electric filling' function button can be manually clicked, the situation that the electromagnetic valve 2 at the outlet of the buffer tank and the electromagnetic valve 3 at the gas-liquid vent are powered off and are in a closed state is confirmed, the electromagnetic valve 5 is isolated in a flow process and powered on and is in a closed state, then a sample inlet pipe at the input end of the sample inlet pressurizing pump 26 is inserted into an external crude mercury container, the rotating speed, the flow and the volume parameters of the sample inlet pressurizing pump 26 are set, the electromagnetic valve 4 for controlling the crude mercury feeding is powered on and is placed in an open state, the sample inlet pressurizing pump 26 is started, and crude mercury is filled into the crude mercury bottle 35. The filled crude mercury is for example about 1000-1500 grams.

And S3, performing a pressure filtration process of the secondary filter: the PLC electric automation control system operates a nitrogen source electromagnetic valve 1, a buffer tank outlet electromagnetic valve 2, a gas-liquid vent electromagnetic valve 3, a crude mercury charging control electromagnetic valve 4, a flow isolating electromagnetic valve 5, a filtering and flushing bypass electromagnetic valve 8, a secondary filter isolating electromagnetic valve 9, a tertiary filter inlet electromagnetic valve 11, a tertiary filter top cleaning electromagnetic valve 12 and a discharge circulation conversion electromagnetic valve 19 to be in a closed (cut-off) state; the crude mercury outlet electromagnetic valve 6, the pre-filter column outlet electromagnetic valve 7, the secondary filter flushing control electromagnetic valve 10 and the sewage discharge electromagnetic valve 20 are in an open (conducted) state; after the flow path on-off state is ensured to be correct through a self-checking program of a PLC electric automatic control system or manually observing the working state of each electromagnetic valve displayed on a display screen, starting a vortex oscillator 30, opening an electromagnetic valve 2 at the outlet of a buffer tank, and performing a secondary filter pressurization filtering process; the PLC electric automation control system calls a pressure comparison condition judgment subroutine, when the difference value of the pressure P1 of the inlet pressure sensor 31 and the pressure P2 of the intermediate pressure sensor 32, namely P1-P2 is not more than the pressure head difference dPh when the filtration is finished, and the pressurizing and filtering time Tosc of the secondary filter is more than 60s or longer, the electromagnetic valve 2 at the outlet of the buffer tank is closed, the vortex oscillator 30 is continuously kept to operate in an oscillating mode, and the operation is finished according to the oscillator timing parameters (the oscillator timing parameters can be generally selected within 120s-600s, for example, the oscillator timing parameters are set to 120s, and the PLC program controls the vortex oscillator 30 to be closed after the Tosc reaches 120 s), so that the oscillating and filtering processes of the coarse mercury vibrating screen are finished.

The pressure head difference dPh after the filtration is finished is a self-defined parameter and can be determined through experiments or calculation. The specific explanation is as follows. A horizontal plane tangent to the bottom of the secondary lower cavity of the secondary filter 22 is set as a reference plane of a pressure head (also called a pressure head), P1-P2 are differences between the pressure point of the inlet pressure sensor 31 and the pressure point of the intermediate pressure sensor 32, the differences between the pressure heads are differences between installation height position pressure difference and friction resistance pressure difference, and a total pressure head difference between two points generated by mercury column height changes in each pipeline in a direction perpendicular to the reference plane of a pipeline through which the pipeline passes in the filling process of the secondary lower cavity of the secondary filter 22, and according to an energy conservation equation, the P1-P2 in the system presents low, high and low approximate single pulse square wave shape characteristics along with a pressure filtering time interval, for example, as shown in fig. 7, an experimental data broken line graph in which the difference between the pressure heads P1-P2 in one embodiment varies along with the pressure filtering time Tosc of the secondary filter. Wherein, about 6s after the start of pressure filtration, P1-P2 is approximately equal to 0.050MPa; when the pressure is about 7s-60s, P1-P2 is approximately equal to 0.105MPa; after about 60s, P1-P2 is approximately equal to 0.042MPa; this feature can therefore be used to determine the end condition of the two-stage filter pressure filtration process. For this embodiment, the head difference dPh at the completion of filtration may be set to, for example, 0.05MPa, and when the secondary filter pressure filtration time Tosc acquired by the PLC program is greater than 65s and P1-P2 < dPh, it may be determined that the pressure filtration of the secondary filter 22 is completed.

And S4, performing a filtering process of a three-stage filter: firstly, ensuring that a nitrogen source electromagnetic valve 1, a buffer tank outlet electromagnetic valve 2, a gas-liquid vent electromagnetic valve 3, a crude mercury feeding control electromagnetic valve 4, a flow isolation electromagnetic valve 5, a filtering and flushing bypass electromagnetic valve 8, a secondary filter isolation electromagnetic valve 9, a tertiary filter inlet electromagnetic valve 11, a tertiary filter top cleaning electromagnetic valve 12, a tertiary filter mercury outlet electromagnetic valve 13, a detection pipe top isolation electromagnetic valve 14, a liquid medicine pump outlet electromagnetic valve 15, a deionized water circulating pump outlet electromagnetic valve 16, a fine mercury filling control electromagnetic valve 17, a deionized water return liquid inlet electromagnetic valve 18 and a discharge circulation conversion electromagnetic valve 19 are in a closed (cut-off) state in an initial state; a crude mercury outlet electromagnetic valve 6, a pre-filter column outlet electromagnetic valve 7, a secondary filter flushing control electromagnetic valve 10 the sewage discharge solenoid valve 20 is in an open (conducting) state; then an inlet electromagnetic valve 11 of the tertiary filter, a top cleaning electromagnetic valve 12 of the tertiary filter and a discharge circulation conversion electromagnetic valve 19 are opened, a flushing control electromagnetic valve 10 of the secondary filter is closed, the system flow path is continuously pressurized, filtered mercury polymerized at high density at the bottom of the secondary filter 22 is extruded into the tertiary filter 23, and finally the filtered mercury enters a lower cavity of the tertiary filter.

Specifically, for example, the system flow path is continuously pressurized for a period of time (e.g., 60 seconds), mercury filtered by the secondary lower cavity of the secondary filter 22 is forced to flow along the path through the tertiary filter inlet solenoid valve 11 and all into the tertiary upper cavity of the tertiary filter 23; then closing a top cleaning electromagnetic valve 12 of the tertiary filter, opening a mercury outlet electromagnetic valve 13 of the tertiary filter and a top isolation electromagnetic valve 14 of the detection pipe, and continuing pressurization, wherein at the moment, mercury in the upper cavity of the tertiary filter can only be filtered along the tertiary filter pipe, and finally enters the lower cavity of the tertiary filter, and further enters a detection pipe 37 through the electromagnetic valve 13; the detection position of the light transmittance detection module 41 is placed in a high detection line U of the detection tube 37 for detection, along with the gradual rise of the mercury liquid level in the detection tube 37, the fluid at the position of the high detection line U is converted into mercury from air or waste water on the upper layer of crude mercury, and the light transmittance detection value is changed from a high-value (generally more than 60 percent) casting to be close to 0 (the detection point is completely blocked by mercury); therefore, a first light transmittance reference value lt0 is set, the range of the first light transmittance reference value is a meaningful range of light transmittance, the value is generally 0-99.5%, for example, 60%, and the first light transmittance reference value can be flexibly selected according to needs; when the detection value of the light transmittance detection module 41 is less than or equal to the first light transmittance reference value lt0, it indicates that the mercury liquid level is located near the high detection line U, and further indicates that all mercury is filtered and enters the three-level lower cavity, so that the PLC electric automatic control system can serve as a finishing condition to stop the pressurizing and filtering process of the three-level filter.

Step S5, deionized water rinsing of mercury is performed in the tertiary filter 23: closing an inlet electromagnetic valve 11 of the three-stage filter, a top isolation electromagnetic valve 14 of the detection pipe, an outlet electromagnetic valve 15 of the liquid medicine pump and a fine mercury filling control electromagnetic valve 17, and then opening a top cleaning electromagnetic valve 12 of the three-stage filter, a mercury outlet electromagnetic valve 13 of the three-stage filter, an outlet electromagnetic valve 16 of the deionized water circulating pump and a discharge circulation conversion electromagnetic valve 19; next, the deionized water circulating pump 28 is opened, a first operating flow speed V1 of the deionized water circulating pump 28 is set (specific values can be selected in the working condition of the pump), deionized water (and mercury is pushed) enters from a discharge port 2309 of the tertiary filter, and then reversely passes through the tertiary filter 23, the tertiary filter top cleaning electromagnetic valve 12, the discharge circulation conversion electromagnetic valve 19, the outlet sewage bottle 40, the sewage discharge mercury removal filter 25 and the sewage discharge electromagnetic valve 20 to be discharged, so that low-density scum impurities on the water surface at the top of mercury in the tertiary filter 23 are cleaned and washed, and the washing time T1 (the washing time T1 is a time parameter input into the PLC electrical automatic control system, and the specific values can be set as required, for example, 60s-90s can be generally taken); after the rinsing is finished, the deionized water circulating pump 28 is turned off.

Further, the three-stage filter 23 is subjected to deionized water reverse buoyancy circulation washing: the discharge circulation switching solenoid valve 19 is closed and the deionized water return inlet solenoid valve 18 is opened. Opening the deionized water circulating pump 28 again, setting a second running flow velocity V2 (the specific value can be selected in the working condition of the pump), starting the closed-loop circulating flushing of the three-stage filter 23, and after the deionized water is pumped out by the deionized water circulating pump 28, sequentially passing through the deionized water circulating pump outlet electromagnetic valve 16, the outlet pressure sensor 33, the detection pipe 37, the three-stage filter mercury outlet electromagnetic valve 13, the three-stage filter 23, the three-stage filter top cleaning electromagnetic valve 12, the deionized water circulating mercury removal filter 24 and the deionized water return liquid inlet electromagnetic valve 18, and returning to the deionized water bottle 39 to form a deionized water mercury cleaning continuous circulating flushing loop; setting the circulating flushing time T2 (the specific value can be set according to the requirement, for example, 300-600 s can be taken generally); after the rinsing sequence is complete, the deionized water circulation pump 28 is turned off.

Step S6, adding a purifying liquid medicine to perform chemical purification circulation: closing an inlet electromagnetic valve 11 of the three-stage filter, a top isolation electromagnetic valve 14 of the detection pipe, an outlet electromagnetic valve 16 of the deionized water circulating pump and a fine mercury filling control electromagnetic valve 17, opening a top cleaning electromagnetic valve 12 of the three-stage filter, a mercury outlet electromagnetic valve 13 of the three-stage filter, an outlet electromagnetic valve 15 of the liquid medicine pump and a discharge circulation conversion electromagnetic valve 19, opening a liquid medicine pump 27, setting the speed and the volume of the pump, setting the pump parameters to be constant-volume CV3 operation (the value range of the volume CV3 can be 0-50 ml), and enabling the purified liquid medicine to enter the three-stage filter 23 through the detection pipe 37; and after the constant volume CV3 is reached, the liquid medicine pump 27 is closed, and the electromagnetic valve 15 of the liquid medicine pump outlet is closed.

Further, the outlet electromagnetic valve 16 of the deionized water circulating pump is opened, the deionized water circulating pump 28 is opened, and the three-stage filter 23 is subjected to secondary circulation deionized water washing: closing the discharge circulation conversion electromagnetic valve 19, opening the deionized water return inlet electromagnetic valve 18, opening the deionized water circulating pump 28, starting to carry out closed-loop washing on the three-stage filter 23 at a set third flow rate V3 (the specific value can be selected in the working condition of the pump), and setting the secondary circulation washing time T3 (the value can be 300 s).

Further, the deionized water circulating pump 28 is closed after the above-mentioned long-term circulation of T3 is completed, the detection tube 37 and the three-stage lower chamber form a communicating vessel, mercury enters the detection tube 37 through the three-stage filter mercury outlet electromagnetic valve 13, the mercury water interface of the three-stage lower chamber is level with the mercury water interface in the detection tube 37, and mercury does not enter a subsequent flow pipeline above the detection tube 37, but forms a relatively stable mercury water interface for light transmittance detection. But the deionized water circulating liquid above the mercury-water interface can continuously pass through the outlet pressure sensor 33, the detection tube top isolation electromagnetic valve 14, the discharge circulation conversion electromagnetic valve 19, the outlet sewage bottle 40, the sewage discharge mercury removal filter 25 and the sewage discharge electromagnetic valve 20 to form a flushing cleaning flow path.

Step S7, detecting whether the mercury purification reaches the standard: the detection position of the light transmittance detection module 41 is arranged on the high-position detection line U for light transmittance detection, and if the light transmittance detection value is not less than the second light transmittance standard value ltu, the purification standard value is indicated. ltu is the second transmittance standard value, which corresponds to the transmittance standard value when the purity of the purified mercury is satisfied after the crude mercury is finally filtered, washed and purified, and the highest allowable content of the impurities in the deionized water circulating liquid is satisfied when the purity of the mercury is satisfied as specified in the laboratory pressure curve of capillary tube, GB/T2650.1-2008, and the second transmittance standard value ltu specifically sets the range according to the corresponding relationship between the deionized water washing pollution degree standard value and the mercury purification standard reaching cleanliness of 99.5%, wherein the range is a meaningful range, for example, the value is taken in the range of 50% -99.5% according to the actual sample condition, and the transmittance detection value is not less than ltu, which indicates that the mercury purity is up to the standard (the purity is more than 99.9%), thereby completing the mercury purification process. If the light transmittance detection value is less than the second light transmittance standard value ltu, the (deionized water reverse) closed-loop flushing of the three-stage filter 23 is repeated, the three-stage filter is stopped after a period of time, mercury enters the detection tube 37 to form a communicating vessel, light transmittance detection is carried out, and the steps are repeated until the light transmittance detection value reaches the standard.

For example, in a 20# series crude mercury sample purification experiment, after filtering through the third filter 23 and four times of circulating washing, the transmittance values of circulating washing liquid of the detection tube corresponding to 8 samples are 65.3%, 68.2%, 71.3%, 73.2%, 75.8%, 76.9%, 77.3% and 78.8%, respectively, and the purities of mercury of the corresponding samples tested by the method are 99.48%, 99.56%, 99.72%, 99.85%, 99.93%, 99.95%, 99.96% and 99.96% in sequence. The transmittance value of 75.8 percent corresponding to the mercury purity of 99.93 percent is selected by the initial evaluation of the sample experiment, the second transmittance standard value of ltu is set to be 75.8 percent, and the transmittance is used as the lower limit value for judging the standard mercury treatment standard under the working condition. The ltu value is influenced to a certain extent by the sectional shape characteristics of the glass tube of the detection tube 37 and the composition of impurity particles and dust in a processed sample, a more complete classification and identification mode is gradually formed by continuously enriching a sample experiment, and the second light transmittance is optimized to reach the selection of a standard value ltu.

Step S8, taking out and subpackaging mercury: placing the light transmittance detection module 41 in a low-level detection line D for light transmittance detection, opening the top cleaning solenoid valve 12 of the tertiary filter, the mercury outlet solenoid valve 13 of the tertiary filter, the discharge cycle switching solenoid valve 19 and the sewage discharge solenoid valve 20, and intermittently opening and closing the fine mercury filling control solenoid valve 17 in a pulsating manner (the time interval of intermittent opening and closing can be 3 levels, dt1, dt2 and dt3, generally dt 1> dt2 > dt3, preferably dt1=300ms, dt2=200ms, dt3=50ms, or selected according to conditions, the range is 0ms-500000 ms), and simultaneously setting the filling intermittent on-off cycle (closing the fine mercury control solenoid valve 17) of the fine mercury filling control solenoid valve 17 when the detection position of the light transmittance detection module 41 is at the low-level detection line D, and when the light transmittance detection value is greater than or equal to the light transmittance value (namely the water-mercury interface has dropped to the lowest allowable control interface, the light transmittance value is the third light transmittance value, which is generally recommended to be set to be 30), ending the filling process of the fine mercury. In short, PLC control software is adopted to automatically control the intermittent opening and closing of the fine mercury filling control electromagnetic valve 17 and gradually narrow the opening and closing interval time window, and meanwhile, the light transmittance of the mercury water interface is detected through the light transmittance, so that the light transmittance reaching the light transmittance threshold value is used as the finishing condition for finishing the fine mercury filling.

The specific process is as follows. Opening the fine mercury filling control electromagnetic valve 17, draining mercury to the fine mercury collecting bottle 36 by means of gravity, closing the fine mercury filling control electromagnetic valve 17 after a duration dt1 (for example, 300 ms), setting the light transmittance detection module 41 at the position of the low-position detection line D, detecting the light transmittance at the bottom of the detection tube 37, and if the light transmittance detection value is approximately equal to 0 (for example, between 0% and 2%), indicating that the detection point is completely shielded by mercury, continuously repeating the above-mentioned intermittent opening and closing with the duration dt1, and detecting the light transmittance when the detection point is closed; and (3) entering a second stage, continuously and intermittently opening and closing the fine mercury filling control electromagnetic valve 17 repeatedly and intermittently until the light transmittance detection value is larger than or equal to ltd1 (for example, 10%), but the duration time of each opening is shortened to dt2 (for example, 200 ms), the light transmittance is detected when the fine mercury filling control electromagnetic valve is closed, entering a third stage, continuously and intermittently opening and closing the fine mercury filling control electromagnetic valve 17 repeatedly and intermittently when the light transmittance detection value is larger than or equal to ltd2 (for example, 30%), but the duration time of each opening is further shortened to dt3 (for example, 50 ms), the light transmittance is detected when the fine mercury filling control electromagnetic valve is closed, and when the light transmittance detection value is larger than or equal to ltd3 (for example, 50), the mercury interface is positioned at the center of the detection point or below the center of the detection point, the fine mercury is basically and completely leaked to the fine mercury collecting bottle 36, so that the fine mercury filling control electromagnetic valve 17 is not opened, and the filling process is ended. This process realizes control and detects mercury water interface, prevents that the quick earial drainage in-process water of mercury from leaking and flowing to smart mercury collecting bottle 36: when the filling process is just started, because the mercury-water interface is higher, the detection is stopped after the leakage flow is allowed to be carried out for a relatively long time, and therefore, the long-time interval and the small light transmittance value are matched; along with the reduction of the mercury-water interface, the short-time interval and the large light transmittance value are gradually adopted for limiting, so that the filling can be more quickly confirmed and stopped when the mercury-water interface is close to the lower line allowed by the filling.

And S9, cleaning and initializing the device: resetting the light transmittance detection module 41 to the position of the low detection line D, and checking the cleaning state of the device; and then operating the PLC electrical automation control system to turn off the power supply of the device, stopping supplying power to each electromagnetic valve and each pump, turning off or waiting each part of the device, finishing all work, and performing sorting, storage and other cleaning work according to operation rules.

When the cleaning state of the device is checked, if the pre-filtering column 21 is found to be seriously polluted by visual inspection, the pre-filtering column 21 can be detached for cleaning or replacement, the pre-filtering column 21 adopted by the invention is a high-temperature reproducible filtering column, when the pollution is serious, each part can be detached, and the pre-filtering column filtering tube 214 (quartz tube) and the high-temperature resistant glass fiber and the quartz sand/quartz glass ball filled in the pre-filtering column filtering tube are put into a high-temperature armor tube furnace mercury extraction device together for high-temperature reproducible treatment; or, the pre-filter column flushing path of the device can be adopted, and the back flushing cleaning is carried out by using deionized water, specifically, the flow isolation solenoid valve 5, the crude mercury outlet solenoid valve 6, the filtration flushing bypass solenoid valve 8, the secondary filter flushing control solenoid valve 10, the tertiary filter top cleaning solenoid valve 12, the detection tube top isolation solenoid valve 14, the liquid medicine pump outlet solenoid valve 15, the fine mercury filling control solenoid valve 17 and the discharge circulation conversion solenoid valve 19 are placed in a stop state, the deionized water circulation pump outlet solenoid valve 16, the tertiary filter mercury outlet solenoid valve 13, the tertiary filter inlet solenoid valve 11, the pre-filter column outlet solenoid valve 7, the secondary filter isolation solenoid valve 9 and the sewage discharge solenoid valve 20 are placed in an open state, the deionized water circulation pump 28 is opened, and a passage is formed by sequentially passing through the opened solenoid valves from the deionized water circulation pump 28 for flushing.

If the secondary filter 22 and the tertiary filter 23 are seriously polluted by visual inspection, an automatic flushing flow path program set in a PLC (programmable logic controller) electrical automation control system can be selected in a corresponding interface on the touch screen, or a flow path design is carried out on an electromagnetic valve at a corresponding position set on the touch screen through manual operation to form a flushing sewage discharge path, the secondary filter 22 and/or the tertiary filter 23 are flushed and cleaned by using the deionized water circulating pump 28, and the flushing sewage flows through the outlet sewage bottle 40 and the sewage discharge mercury removal filter 25 to carry out mercury removal purification, so that the environment protection and standard reaching of the discharged sewage are ensured.

For example, the flush path of the secondary filter 22 may be set to: the process isolation electromagnetic valve 5, the crude mercury outlet electromagnetic valve 6, the pre-filter column outlet electromagnetic valve 7, the filtration flushing bypass electromagnetic valve 8, the secondary filter isolation electromagnetic valve 9, the tertiary filter top cleaning electromagnetic valve 12, the detection tube top isolation electromagnetic valve 14, the liquid medicine pump outlet electromagnetic valve 15, the fine mercury filling control electromagnetic valve 17 and the discharge circulation conversion electromagnetic valve 19 are in a cut-off state, the deionized water circulating pump outlet electromagnetic valve 16, the tertiary filter mercury outlet electromagnetic valve 13, the tertiary filter inlet electromagnetic valve 11, the secondary filter flushing control electromagnetic valve 10 and the sewage discharge electromagnetic valve 20 are in an open state, and a passage is formed by sequentially passing through the opened electromagnetic valves from the deionized water circulating pump 28 for flushing.

For another example, the flushing path of the tertiary filter 23 may be set to: the two-stage filter isolation electromagnetic valve 9, the two-stage filter flushing control electromagnetic valve 10, the three-stage filter inlet electromagnetic valve 11, the detection tube top isolation electromagnetic valve 14, the liquid medicine pump outlet electromagnetic valve 15, the fine mercury filling control electromagnetic valve 17 and the deionized water return inlet electromagnetic valve 18 are in a stop state, the deionized water circulating pump outlet electromagnetic valve 16, the three-stage filter mercury outlet electromagnetic valve 13, the three-stage filter top cleaning electromagnetic valve 12, the discharge circulation conversion electromagnetic valve 19 and the sewage discharge electromagnetic valve 20 are in an open state, and a passage is formed by sequentially passing through the opened electromagnetic valves from the deionized water circulating pump 28 for flushing.

In addition, a small circulation loop can be formed along the outlet electromagnetic valve 16 of the deionized water circulating pump, the top isolation electromagnetic valve 14 of the valve detection tube, the deionized water circulating mercury removal filter 24, the deionized water liquid return inlet electromagnetic valve 18 and the deionized water tank 39, so that the functions of cleaning the upper part of the detection tube 37 and washing, overhauling and testing the deionized water circulating mercury removal filter 24 are realized.

In another embodiment, a multistage filter-press membrane-breaking mercury purification device under normal temperature conditions is provided according to fig. 4A and 4B, and is a multistage visual filter that uses multistage filter-press membrane-breaking and deionized water buoyancy reverse circulation flushing and trace chemical reagent oxide impurity removal purification technologies, and experimental filtration conditions for specific crude mercury working conditions can be optimized by adopting mesh screen combinations with different mesh numbers in the filter, so that a mixed liquid phase system consisting of impurity oxides and dust particles contained in mercury with mercury purity of 99.5% or less can be filtered, membrane-breaking, purified and purified under normal temperature conditions. The multi-stage filter-pressing membrane-breaking mercury purification device under the normal temperature condition comprises an upper cavity, a middle part and a lower cavity which are connected in a combined mode, wherein the upper cavity and the lower cavity are of inner cavity structures which are identical in size and are conical at two ends of a middle cylinder, the middle part is a reducing multi-stage filtering visual tube, the whole structure is in a dumbbell shape vertically arranged from top to bottom, and waste mercury liquid enters from an inlet at the top end of the upper cavity and flows out from an outlet at the bottom of the lower cavity; the upper cavity body comprises a three-level upper inlet seat and a three-level upper flange seat which are hermetically connected up and down, the inner cavity of the three-level upper inlet seat is in an inverted cylindrical funnel shape, the inner cavity of the three-level upper flange seat is in a conical funnel shape, and the calibers of the inner cavities of the three-level upper inlet seat and the three-level upper flange seat are the same; the lower cavity comprises a third-stage lower flange seat and a third-stage lower outlet seat which are hermetically connected up and down, the inner cavity of the third-stage lower flange seat is an inverted conical funnel, the inner cavity of the third-stage lower outlet seat is in a cylindrical funnel shape, and the calibers of the inner cavities of the upper cavity and the lower cavity are the same; the middle part is a necking cylindrical quartz glass material three-stage hollow filter column, and a plurality of homocircular filter screens with different holes are arranged in the middle part; the periphery of the filter screen is hermetically connected with a three-stage hollow filter column, and the three-stage hollow filter column is connected with the inner cavity of the upper flange base and the lower flange base.

Preferably, the three-stage hollow filter column comprises a first inner column and a second inner column which are made of quartz glass materials, the first inner column and the second inner column are both in a hollow cylinder shape, the bottom area of the first inner column is the same as that of the second inner column, and the first inner column and the second inner column are in sealing connection through flanges and sealing gaskets; the first inner column is internally and hermetically connected with a first-stage filter screen and a second-stage filter screen which are in equal circles with the first inner column; the second inner column is internally and hermetically connected with a third-level filter screen which is in an equal circle with the second inner column and a stainless steel mesh sheet at the bottom; the top end of the first inner column is hermetically connected with the bottom end of the inner cavity of the three-level upper flange seat, the bottom end of the second inner column is connected with the top end of the inner cavity of the three-level lower flange seat, and all the joints are provided with sealing rings for sealing connection; the three-stage hollow filter column is respectively connected with the upper flange seat and the lower flange seat. The first inner column is provided with 100 meshes, a 160-mesh filter screen is arranged below the first inner column, and the second inner column is provided with a 200-mesh filter screen or other mesh combination schemes are optimally combined according to the requirement of filter precision. And extrusion rings are respectively arranged at the positions of the filter screens between the three-stage hollow filter columns and the inner column. The inlet end at the top of the inner cavity of the upper inlet seat at the third stage is connected with a quick connector for filling nitrogen; the outlet end at the bottom of the inner cavity of the third-level lower outlet seat is connected with a quick connector for connecting a deionized water pipe, the deionized water pipe is connected with a circulating pump, and pumping deionized water into the inner cavity of the outlet seat at the lower part of the third stage, and repeatedly washing the inner cavity of the device from bottom to top.

Further, in another preferred embodiment, the upper end and the lower end of the integral structure of the multistage filter-pressing membrane-breaking mercury purification device under normal temperature condition are designed by adopting a dumbbell-like structure, namely a cone and cylindrical cone combined inner cavity, the middle of the integral structure is connected by adopting a reducing hole multistage filter visible tube combination, and the structure is a dumbbell structure vertically arranged up and down; waste mercury liquid flows in from the top of the upper end and flows out from the outlet of the lower end, and the outlet of the lower end is connected with a deionized water pipe and a circulating pump; the multi-stage membrane breaking purification, the buoyancy reverse circulation flushing filtration and the layered extraction purification can be realized by controlling the gravity difference and the flow direction of the system pressure and the fluid with different densities in the process, so that the normal-temperature physical separation and purification function of a mercury-impurity oxide membrane-water ternary combination system is realized, and the advantages of environmental protection, safety and reliability are realized.

The upper end of the multistage filter-pressing membrane-breaking mercury purification device can be connected with a filter press or a pressure source under the normal temperature condition to provide pressure input. The multi-stage filter-pressing membrane-breaking mercury purification device under the normal temperature condition comprises an upper cavity, a middle necking quartz tube and a lower cavity from top to bottom. The last cavity includes tertiary upper portion entry seat and tertiary upper portion flange seat, and tertiary upper portion entry seat inner chamber is for invering cylindrical funnel shape, and tertiary upper portion flange seat inner chamber is for the toper hourglass hopper-shaped, and both inner chamber bores are the same. The third-level upper inlet seat is positioned on the third-level upper flange seat, and the inner cavities of the third-level upper inlet seat and the third-level upper flange seat are butted. And a third O-shaped sealing ring larger than the inner cavity is arranged between the third-level upper inlet seat and the third-level upper flange seat, and the third O-shaped sealing ring are hermetically connected through screws and nuts. The inverted cone-shaped cylindrical design of the three-level upper inlet seat can reduce the adsorption of mercury beads and maximize the internal storage. The tertiary upper inlet seat and the tertiary upper flange seat form a compact shape, and the upper half part of the sealed mercury collecting cavity is formed. The toper design of tertiary upper portion flange seat, natural transition reduces inside mercury pearl and adsorbs, and the flange formula design can bear higher pressure, is convenient for simultaneously can not harm the dismouting. The lower cavity is the same as the upper cavity in volume, the lower cavity comprises a third-level lower flange seat and a third-level lower outlet seat, the third-level lower flange seat is the same as the third-level upper flange seat in size and opposite in direction, the third-level lower outlet seat is the same as the third-level upper inlet seat in size and opposite in direction, the third-level lower flange seat is arranged on the third-level lower outlet seat, and a fourth O-shaped sealing ring 7 larger than the inner cavity is arranged between the third-level lower flange seat and the third-level lower outlet seat and is in sealing connection with the upper cavity through screws and nuts.

Stud bolts are symmetrically connected to two sides of the three-level upper flange seat and the three-level lower flange seat. The upper and lower joints are connected through nuts and screws. The middle quartz column is positioned in the double-ended stud. The three-level upper flange seat, the stud and the three-level lower flange seat form a compact shape, the upper part and the lower part are extruded and sealed, the middle part is firmly fixed, and the whole device is integrated. The inlet end at the top of the inner cavity of the upper inlet seat at the third stage is connected with a quick connector which can be filled with high-purity nitrogen to generate protective gas inside the cavity; the outlet end of the bottom of the inner cavity of the third-level lower outlet seat is connected with a quick connector, the quick connector is connected with a deionized water pipe, the deionized water pipe is connected with a circulating pump, deionized water is pumped into the lower cavity through the quick connector, and floating and sinking and metal oxides in the crude mercury are washed from bottom to top, so that the further purification effect of the mercury is achieved. The quick-connection joint adopts a form of a thread at one end and a quick-connection joint at the other end, so that the whole body can be conveniently assembled and disassembled with the outside; the quick-connection joint can be changed into a one-head thread one-head double quick-connection joint. The middle part, namely the middle quartz column, is a cylindrical quartz glass three-stage hollow filter column, the upper part is connected with the bottom end of the inner cavity of the flange seat at the upper part, and the lower part is connected with the top end of the inner cavity of the flange seat at the lower part. The middle part is provided with a circular three-stage filter screen vertical to the axial direction of the three-stage hollow filter column.

The middle part is made of quartz glass, so that visibility is realized, the pollution state is convenient to observe, and the filter screen is cleaned or replaced in time. The cylindrical hollow first inner column and the cylindrical hollow second inner column which are made of quartz glass materials are sequentially arranged in the three-stage hollow filter column from top to bottom, the bottom areas of the first inner column and the second inner column are the same, and the first inner column and the second inner column are connected in a sealing mode through flanges, O sealing rings of the inserting portion and screws and nuts. The first inner column is internally provided with a first-stage filter screen and a second-stage filter screen which are vertical to the axial direction of the first inner column, the first-stage filter screen is positioned on the second-stage filter screen and has a certain distance relatively, the filter screens are circular, and the size of the filter screens is equal to the bottom area of the first inner column. Furthermore, all be equipped with in first interior post and the second with its axle direction perpendicular tertiary filter screen and stainless steel mesh sheet, the filter screen is circular, and its size equals with post bottom surface area in the second, and stainless steel mesh sheet is located post bottom in the second. The filter screen and the periphery of the mesh slice are hermetically connected with the inner column. Preferably, the first-stage filter screen is 100 meshes, the second-stage filter screen is 150 meshes, the third-stage filter screen is 200 meshes, and the filter screens can also be replaced by nylon meshes. After the filter pressing is carried out for a certain pressure, the mercury liquid is subjected to the filter pressing step by step from top to bottom. More preferably, the three-stage filter screen forms three-stage filtration, which filters pollutant particles adsorbed in mercury liquid from large to small, and has a filtering and membrane breaking effect under certain pressure to overcome surface tension and filter aggregates with smaller primary particle size step by step. In a preferred embodiment, according to the purity standard, a multi-stage filtering screen combination design can be adopted, and the screen mesh combination and the control times of the screening cycle can be replaced and optimized according to the characteristics of the filtering fluid, so that the expected purification standard reaching the purity standard can be realized.

Extrusion rings are arranged between the three-level hollow filter column and the inner column at positions corresponding to the first-level filter screen, the second-level filter screen and the third-level filter screen. The damage of the inner column caused by the downward flow and extrusion of the mercury liquid is reduced. The top of the first inner column is connected with the bottom end of the inner cavity of the flange seat at the upper part of the third level, an O-shaped sealing ring at the inner side of the upper part is arranged between the connecting positions of the first inner column and the third inner column, the bottom of the second inner column is connected with the top end of the inner cavity of the flange seat at the lower part of the third level, and an O-shaped sealing ring at the lower part is arranged between the connecting positions. Realize the sealing connection and avoid the side leakage of the mercury liquid. The top of the three-level hollow filter column is connected with a three-level upper flange seat, an upper sealing ring is arranged between the top of the three-level hollow filter column and the three-level upper flange seat, the upper sealing ring is extruded and sealed, an O-shaped sealing ring on the inner side of the upper portion and the three-level upper flange seat are compressed, top sealing is formed, mercury can only penetrate out from a middle through hole, and side leakage cannot be generated. The bottom of the three-stage hollow filter column is connected with a three-stage lower flange seat, and a lower O-shaped sealing ring is arranged between the three-stage hollow filter column and the three-stage lower flange seat for extrusion sealing. Similarly, the lower O-shaped sealing ring and the three-level lower flange seat are tightly pressed to form top sealing, and mercury can only penetrate out of the middle through hole without side leakage.

The quartz column structure on both sides is more pressure-resistant, reduces the damaged condition. The connecting ends of the two inner columns adopt a screw and nut detachable combined sealing structure, so that the disassembly, the cleaning, the part replacement and the repair are convenient; the back flushing cleaning function of the process system can be realized under the condition of not being disassembled. The inlet and outlet quick disassembly and assembly structure can realize quick assembly, sealing and fault detection. The upper and lower two parts of main body material is polytetrafluoroethylene, and the sealing washer is the fluorine glue material, all does not produce chemical reaction with mercury.

According to the technical scheme, the functional structure performs multi-stage filter pressing, membrane breaking, flushing and purification in a specially designed closed cavity (a visible filter) according to the principle that mercury is in a normal-temperature maximum-density liquid phase and has huge density difference with a mechanical impurity particle oxidation membrane and water. According to the multi-phase system large-density differential layer extraction principle, the buoyancy reverse circulating flushing filtration and layered extraction purification effects of the mercury-impurity oxide film-water ternary combination system are realized, the normal-temperature physical purification of mercury is realized, and the advantages of environmental protection, safety and reliability are achieved.

In summary, the multi-stage filter-pressing membrane-breaking mercury purification device and method provided by the invention mainly have the following beneficial technologies:

1. according to the scheme, the purity of the crude mercury is gradually improved by a multi-stage filter-pressing membrane-breaking deionized water buoyancy reverse circulation purification technology under a normal temperature condition, and finally the purity of the purified mercury is over 99.9%, so that the purity of the purified mercury meets the mercury purity specified by a laboratory mercury-pressing capillary pressure curve experimental standard GB/T2650.1-2008; high-temperature vacuum distillation or chemical-electrochemical treatment of the traditional mercury purification method is not adopted, so that the problems that high-temperature virulent mercury vapor or secondary dangerous waste is generated and the application scene of small-scale mercury purification is not suitable are solved; meanwhile, the technical problems of regeneration treatment for purifying pollutants and mercury removal and standard discharge of discharged sewage are solved, and a brand new technical path is opened up for purification treatment and reutilization of laboratory-scale crude mercury.

2. The scheme of the invention has reliable performance, safety, environmental protection and high environmental applicability, can realize on-site timely environmental protection treatment by a mercury laboratory, and reduces the risk of secondary pollution diffusion transfer; and the absolute amount of mercury in a laboratory can be reduced, the recycling is promoted, good economic benefits and environmental protection social benefits are achieved, and the requirement of environmental protection policy encouragement is met.

3. The coarse mercury vibrating screen secondary filter and the tertiary fine filter developed and designed by the scheme of the invention have the upper and lower ends which adopt a cone-like body plus cylinder combined inner cavity design, the middle is connected with the secondary or tertiary filter pipe in a reducing hole mode in a combined mode, the structure is a dumbbell-shaped structure with the upper and lower ends being wide and the middle being thin, and the secondary filter can realize the vibrating screen friction and constant flow variable cross-section tubule acceleration effect and the front and rear differential pressure expansion effect of a narrow tube throttling interface of a Venturi tube to enhance the friction mixing filtering effect; the three-stage filter structure design not only applies the Venturi tube effect, but also adopts three layers of screens which gradually reduce meshes (namely increase the mesh number of the screens), so that more tiny variable flow cross section mesh effects are formed, and the microsphere particle high-interfacial tension microsphere liquid drops containing dust and oxide films are further extruded and deformed and frictionally deformed when passing through the mesh holes, so that the filtering effect is further improved.

4. According to the scheme, a pre-filtering column, a secondary filter and a tertiary filter are adopted to form a multi-stage screen mesh number increasing filtering combination, a pressure extrusion continuous membrane breaking optimization functional structure system is constructed, and the properties of normal-temperature high-density liquid and high specific surface tension of mercury and the multi-stage screen extrusion friction membrane breaking effect are fully utilized.

5. The scheme of the invention realizes the buoyancy reverse circulating flushing filtration and layered extraction purification effects of the mercury-impurity oxide film-water ternary combination system by using the large-density differential layer extraction principle of the multiphase system, realizes the normal-temperature physical purification of mercury, and has the advantages of environmental protection, safety and reliability.

6. The scheme of the invention adopts PLC programming, synchronous touch screen flow, automatic quality control detection, micro-integration manufacturing of a plurality of intelligent technologies such as discharge mercury removal purification and the like, the purposes of minimizing field occupation, realizing environmental protection and standard reaching of discharged waste liquid and diversifying application scenes under the normal temperature condition are achieved.

All the above embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same, and all other extended embodiments obtained by a person of ordinary skill in the art without making innovative efforts based on the embodiments of the present invention belong to the protection scope of the present invention. Although the present invention has been described in detail with reference to the foregoing examples, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the embodiments of the invention.

Claims

1. A three-stage filter is suitable for a multi-stage filter-pressing membrane-breaking mercury purification device under the normal temperature condition and is characterized by comprising a three-stage upper inlet seat, a three-stage upper flange seat, a three-stage filter pipe, a three-stage lower flange seat and a three-stage lower outlet seat which are sequentially connected from top to bottom;

a third O-shaped sealing ring is arranged between the third-stage upper inlet seat and the third-stage upper flange seat, and the upper part of the third O-shaped sealing ring is abutted against the lower surface of the third-stage upper inlet seat; the third-level lower outlet seat is in a bowl shape, a third-level filter discharge port with an interface is arranged at the lower part of the third-level lower outlet seat, a fourth O-shaped sealing ring is arranged between the third-level lower outlet seat and the third-level lower flange seat, and the upper part of the fourth O-shaped sealing ring is abutted to the lower surface of the third-level lower flange seat.

2. The tertiary filter according to claim 1, wherein an annular receiving groove is defined in an upper surface of the tertiary upper flange seat, and the third O-ring is inserted into the receiving groove.

3. The three-stage filter according to claim 1, wherein the upper inlet seat of the three-stage filter is in an inverted bowl shape, and the upper part of the upper inlet seat of the three-stage filter is provided with a feed port of the three-stage filter and an outlet of the upper part of the three-stage filter, which are communicated with each other, and both of the feed port and the outlet are provided with interfaces for connection.

4. The tertiary filter according to claim 1, wherein the tertiary upper inlet seat is connected with the tertiary upper flange seat through bolts, and the tertiary upper flange seat has through holes at the bottom and is communicated with the upper end of the tertiary filter pipe.

5. The tertiary filter according to claim 4, wherein an annular receiving groove is defined in an upper surface of the tertiary lower outlet seat, and the fourth O-ring is inserted into the receiving groove.

6. The three-stage filter according to claim 1, wherein the three-stage upper flange seat and the three-stage lower flange seat are correspondingly provided with a plurality of through holes penetrating from top to bottom at positions close to the edges, a plurality of studs penetrate through the through holes, and two ends of the studs are fixed by nuts matched with each other, so that the three-stage filter pipe is clamped and fixed between the three-stage upper flange seat and the three-stage lower flange seat.

7. The three-stage filter according to claim 1, wherein the bottom of the three-stage upper flange seat and the top of the three-stage lower flange seat are provided with a groove or a flange for positioning, and two ends of the three-stage filter tube are respectively embedded into the groove or the flange.

8. The three-stage filter according to claim 1, wherein the three-stage filter pipe comprises a three-stage hollow filter column which is through from top to bottom, and a plurality of layers of filter screens of the three-stage filter are distributed in the three-stage hollow filter column along the length direction.

9. The three-stage filter according to claim 8, wherein the filter screen of each three-stage filter is held and fixed by an extrusion ring and an inner column, and the extrusion ring and the inner column are both hollow cylindrical.

10. The tertiary filter according to claim 1, wherein the tertiary lower flange seat is provided at the top with an annular flange and has an annular receiving groove on the inner side, and the annular receiving groove is embedded with a lower O-ring.