Three-dimensional sand box simulation system for multiphase extraction remediation of soil and underground water

Abstract

The three-dimensional sand box simulation system comprises a water supply mechanism, a sand box and a lifting and repairing mechanism, a partition plate is fixedly installed in the sand box, a plurality of water distribution holes are formed in the surface of the partition plate in a penetrating mode, the interior of the sand box is divided into a water distribution bin and a test bin through the partition plate, and the water distribution bin and the test bin are communicated through the water distribution holes. The test bin is used for filling a soil medium, a water inlet hole communicated with the water distribution bin is formed in the outer wall of the sand box in a penetrating manner, the water inlet hole is communicated with the water supply mechanism, and a plurality of water outlet holes communicated with the test bin are formed in the outer wall of the sand box in a penetrating manner; by arranging the sand box, the partition plate, the water distribution holes, the cover plate, the sampling holes, the extraction remediation mechanism and the like, the migration rule and the multiphase extraction remediation rule of volatile organic pollutants in a soil and underground water system can be accurately researched, so that a remediation scheme is optimized, scientific guidance is provided for actual remediation engineering, and the economic benefit is increased. The efficiency of repairing work is improved, and the maximization of environmental benefits is realized.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of contaminated soil and groundwater remediation technology, in particular to a three-dimensional sand box simulation system for soil and groundwater multi-phase extraction remediation. BACKGROUND

[0002] In recent years, in the contaminated soil and groundwater remediation technology, from the development trend of multi-phase extraction remediation research on contaminated sites at home and abroad, the existing sand box device has not made full research on the optimization of multi-phase extraction remediation process parameters when exploring the removal of volatile organic matter contaminated soil and groundwater by multi-phase extraction, and only stays on the discussion of single influencing factor.

[0003] In addition, most of the existing indoor devices for simulating the migration and remediation of volatile organic pollutants in soil and groundwater system stay in the horizontal two-dimensional sand box device, lack of consideration of three-dimensional depth well location and pressure process parameter combination change research, and cannot make reasonable optimization reference to true process parameters, and the existing device research also does not consider the volatile loss problem of volatile organic matter in the sand box system, and underestimates the residual concentration of pollutants in the sand box system.

[0004] Therefore, we propose a three-dimensional sand box simulation system for soil and groundwater multi-phase extraction remediation. CONTENT OF THE UTILITY MODEL

[0005] The utility model aims at providing a three-dimensional sand box simulation system for soil and groundwater multi-phase extraction remediation, which explores the well arrangement mode and key process parameter optimization of volatile organic matter multi-phase extraction in three-dimensional space in a relatively sealed environment, simulates the required technical parameter consideration and space-time combination control of real engineering, and provides technical support for the reasonable setting of well arrangement position and process parameters of actual site contaminated soil and groundwater multi-phase extraction remediation.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical scheme:

[0007] A three-dimensional sand box simulation system for soil and groundwater multi-phase extraction remediation, comprising a water supply mechanism, a sand box and an extraction and remediation mechanism, a partition plate is fixedly installed in the sand box, a plurality of water distribution holes are arranged through the surface of the partition plate, the partition plate divides the interior of the sand box into a water distribution chamber and a test chamber, the test chamber is used for filling soil medium, a water inlet hole is arranged through the outer wall of the sand box and communicates with the water distribution chamber, the water inlet hole communicates with the water supply mechanism, a plurality of water outlet holes are arranged through the outer wall of the sand box and communicate with the test chamber, a cover plate is sealingly connected to the top of the sand box, a plurality of sampling holes for penetrating the extraction and remediation mechanism are arranged through the cover plate, the extraction and remediation mechanism comprises an extraction outer pipe, and an extraction inner pipe is movably and sealingly penetrated into the top end of the extraction outer pipe.

[0008] As a further scheme of the present utility model: the outer wall of the sand box is fixedly installed with a water storage box, the water outlets are all communicated with the water storage box, a drain hole is penetrated through the bottom of the water storage box, and the drain hole is communicated with the water storage tank through a hose.

[0009] As a further scheme of the present utility model: the outer wall of the lifting inner pipe is sleeved with a rubber sleeve, and the bottom end of the rubber sleeve is located in the top end opening of the lifting outer pipe.

[0010] As a further scheme of the present utility model: the bottom end of the lifting outer pipe is blocked, and a plurality of screen holes are penetrated through the bottom end of the outer wall of the lifting outer pipe.

[0011] As a further scheme of the present utility model: the lifting repair mechanism further comprises a waste liquid barrel, a barrel cover is detachably and sealingly connected to the top end opening of the waste liquid barrel, the barrel cover is connected with a vacuum pump through an air suction pipe, and the barrel cover is communicated with the top end of the lifting inner pipe through a liquid suction hose.

[0012] As a further scheme of the present utility model: the water supply mechanism comprises a peristaltic pump, a water supply pipe is connected to the peristaltic pump, and the water outlet end of the water supply pipe is communicated with the water inlet hole.

[0013] As a further scheme of the present utility model: a rubber plug is installed in the sampling hole.

[0014] Compared with the prior art, the present utility model has the beneficial effects that:

[0015] The present utility model can accurately study the migration rule of volatile organic pollutants in the soil and groundwater system and the multiphase extraction repair rule by setting the sand box, the partition plate, the water distribution hole, the cover plate, the sampling hole and the lifting repair mechanism, thereby optimizing the repair scheme, providing scientific guidance for actual repair engineering, improving the efficiency of repair work, and maximizing the environmental benefits. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 It is a structural schematic view of a three-dimensional sand box simulation system for soil and groundwater multiphase extraction repair.

[0017] Figure 2 It is a structural schematic view of a sand box in a three-dimensional sand box simulation system for soil and groundwater multiphase extraction repair.

[0018] Figure 3 It is a sectional structural schematic view of a sand box in a three-dimensional sand box simulation system for soil and groundwater multiphase extraction repair.

[0019] Figure 4 It is Figure 3 It is an enlarged view of A in the middle.

[0020] Figure 5 It is a distribution position schematic view of the pollutant injection point, the monitoring point and the repair point in the embodiment of the utility model.

[0021] Among them, the sand box 1, the partition 2, the water distribution hole 3, the water distribution bin 4, the test bin 5, the water inlet hole 6, the water outlet hole 7, the water storage box 8, the drainage hole 9, the cover plate 10, the sampling hole 11, the rubber plug 12, the lifting outer tube 13, the screen hole 14, the rubber sleeve 15, the lifting inner tube 16, the water supply pipe 17, the water storage tank 18, the liquid pumping hose 19, the waste liquid barrel 20, the barrel cover 21, the air pumping pipe 22. DETAILED DESCRIPTION

[0022] The technical scheme in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the ordinary skilled in the art without creative labor belong to the protection scope of the utility model.

[0023] Please refer to Figures 1-4 In the embodiment of the utility model, a three-dimensional sand box simulation system for soil and underground water multi-phase pumping remediation includes a water supply mechanism, a sand box 1 and a pumping remediation mechanism. The sand box 1 is made of organic glass plate with a thickness of 1.5 cm, and the specific size is 40 cm long, 30 cm wide and 30 cm high. A partition 2 made of organic glass is fixedly installed in the sand box 1. The partition 2 is 1 cm thick, and the top end is flush with the top of the sand box 1. The surface of the partition 2 is provided with 196 water distribution holes 3 in total, which are arranged in 14 rows and 14 columns. The diameter of the water distribution hole 3 is 0.5 mm, and the distance between adjacent water distribution holes 3 is 2 cm. The partition 2 divides the inside of the sand box 1 into a water distribution bin 4 and a test bin 5. The test bin 5 is used for loading soil medium. A water inlet hole 6 with a diameter of 1 cm is provided in the left side outer wall of the sand box 1 at a height of 25 cm and is in communication with the water distribution bin 4. The water inlet hole 6 is in communication with the water supply mechanism. Fifteen water outlet holes 7 with a diameter of 1 cm are punched in the right side outer wall of the sand box 1 at a height of 20 cm and are in communication with the test bin 5. An organic glass cover plate 10 is sealingly connected to the top of the sand box 1. The thickness of the cover plate 10 is 3 cm. The cover plate 10 is provided with 35 sampling holes 11 in total, which are arranged in 7 rows and 5 columns and are used for penetrating the pumping remediation mechanism. The diameter of the sampling hole 11 is 1 cm, and the distance between the holes is 5 cm. The pumping remediation mechanism includes a lifting outer tube 13. The top end of the lifting outer tube 13 is movably sealingly penetrated by a lifting inner tube 16. The lifting outer tube 13 is an organic glass tube with a length of 40 cm and a diameter of 1 cm. The lifting inner tube 16 is an organic glass tube with a length of 40 cm and a diameter of 0.5 cm.

[0024] Specifically combined Figure 3The outer wall of the sand box 1 is fixedly provided with a water storage box 8, the water outlets 7 are communicated with the water storage box 8, the bottom of the water storage box 8 is provided with a drain hole 9, the diameter of the drain hole 9 is 1cm, and the drain hole 9 is communicated with a water storage tank 18 through a hose.

[0025] Specifically combined Figure 3 In one embodiment of the utility model, the outer wall of the lifting inner pipe 16 is sleeved with a rubber sleeve 15, and the bottom end of the rubber sleeve 15 is located in the top end opening of the lifting outer pipe 13.

[0026] Specifically combined Figure 3 In one embodiment of the utility model, the bottom end of the lifting outer pipe 13 is blocked, and a plurality of sieve holes 14 are arranged in the bottom end of the outer wall of the lifting outer pipe 13, the diameter of the sieve hole 14 is 0.1cm, and the sieve hole 14 is the position for extracting liquid, and the depth of sampling can be controlled.

[0027] Specifically combined Figure 1 In one embodiment of the utility model, the lifting repair mechanism further comprises a waste liquid barrel 20, the top end opening of the waste liquid barrel 20 is detachably and sealingly connected with a barrel cover 21, the barrel cover 21 is connected with a vacuum pump with adjustable vacuum degree through a suction pipe 22, and the barrel cover 21 is communicated with the top end of the lifting inner pipe 16 through a liquid suction hose 19; when the vacuum pump is started, the air in the waste liquid barrel 20 can be extracted, so that the liquid is extracted into the waste liquid barrel 20 through the liquid suction hose 19 and the lifting inner pipe 16 under the negative pressure.

[0028] In addition, the water supply mechanism comprises a peristaltic pump, the peristaltic pump is connected with a water supply pipe 17, and the water outlet end of the water supply pipe 17 is communicated with the water inlet hole 6.

[0029] The sampling hole 11 is provided with a rubber plug 12.

[0030] Specifically combined Figure 5 In one specific embodiment of the utility model,

[0031] Medium filling: the embodiment is configured with 80-120 mesh actual soil: quartz sand = 1:4 mixed medium, the prepared soil medium is fully mixed and filled into the test bin 5: the treated soil medium is filled into the test bin 5 at 5cm per layer, a total of 6 times of filling are needed, the weight of the medium is weighed by using an electronic balance during each filling, the beaker is used for uniform filling during filling, the wood board is used for compaction to make the soil medium uniformly distributed, the soil medium is uniformly filled to the top of the sand box, and the sand box 1 is covered with the cover plate 10 after filling is completed.

[0032] Saturation zone formation: After the soil medium is filled, pure water is injected into the water distribution chamber 4 by setting a peristaltic pump at a water injection flow rate of 100 mL / min, and the pure water slowly flows into the test chamber 5 after passing through the water distribution holes 3. In this process, the air in the soil medium pores in the test chamber 5 is completely displaced, and finally a saturated three-dimensional sand box model is formed. After the water level is stable, the water injection flow rate is reduced to 20 mL / min.

[0033] Contaminant migration and sampling: A 20 mL solution of 100 mg / L of 1,4-dichlorobenzene is prepared as the contaminant in this example, and the prepared 1,4-dichlorobenzene solution is injected into the test chamber 5 in two times using a 10 mL syringe. The injection position is at a depth of 10 cm, so as to avoid upward volatilization of the contaminant. No external pressure is added during the entire process, and the contaminant undergoes free migration in the soil under the action of gravity and water flow. The entire migration process takes about 8 h. During the migration process, soil solution sampling is performed at multiple depths (10, 15, and 20 cm) of the four monitoring points (indicated positions) using a long needle cylinder. The sampling times are 0, 1, 2, 4, 6, and 8 h, and the contaminant concentration of the sample is determined. Figure 5 Figure 5 Contaminant migration and sampling: A 20 mL solution of 100 mg / L of 1,4-dichlorobenzene is prepared as the contaminant in this example, and the prepared 1,4-dichlorobenzene solution is injected into the test chamber 5 in two times using a 10 mL syringe. The injection position is at a depth of 10 cm, so as to avoid upward volatilization of the contaminant. No external pressure is added during the entire process, and the contaminant undergoes free migration in the soil under the action of gravity and water flow. The entire migration process takes about 8 h. During the migration process, soil solution sampling is performed at multiple depths (10, 15, and 20 cm) of the four monitoring points (indicated positions) using a long needle cylinder. The sampling times are 0, 1, 2, 4, 6, and 8 h, and the contaminant concentration of the sample is determined.

[0034] Multi-phase extraction remediation and sampling: After the contaminant migration is completed, multi-phase extraction remediation is started. As shown in FIG. 6, three extraction wells (i.e., the extraction outer pipes 13 are inserted into the soil medium from the sampling holes 11) are arranged at the remediation points. The well spacing is about 7.07 cm, and the depth of each extraction outer pipe 13 inserted into the sand box is 17 cm. The screen holes 14 are wrapped with gauze to ensure that the soil medium does not block the sand holes 14 during multi-phase extraction remediation. After the pipeline is connected, the vacuum pump is turned on for extraction. The vacuum degree parameters of each vacuum pump are all 5 Kpa, and the remediation completion time is 6 h. Similarly, sampling is performed at each depth of the four monitoring points, and the waste liquid collected by the three waste liquid barrels 20 is also sampled and the volume of the extracted waste liquid is recorded. The sampling times during the extraction remediation process are 1, 2, 3, 4, and 6 h. The 1,4-dichlorobenzene concentration detected by liquid chromatography is used to observe the process and effect of multi-phase extraction remediation. Figure 5 Optimization of well arrangement position and vacuum degree parameters: By changing the positions of the sampling holes 11 of the extraction outer pipes 13 inserted on the cover plate 10 and the vacuum degree parameters of the vacuum pumps, the process parameter setting scheme with the optimal multi-phase extraction remediation effect is explored. The vacuum degree parameters of each vacuum pump can be selected in the range of 1-1 Kpa, and the optimized arrangement positions of each extraction outer pipe 13 can be determined by using the optimization algorithm constructed by the groundwater simulation software TMVOC and MATLAB.

[0035]

[0036] ​​Although the utility model has been explained in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments or make equivalent replacement to part of the technical features, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A three-dimensional sandbox modeling system for soil and groundwater multiphase extraction remediation, characterized by: Including water supply mechanism, sand box (1), and extract repair mechanism, the baffle (2) is fixedly installed in the sand box (1), a plurality of water distribution holes (3) are arranged on the surface of the baffle (2), the baffle (2) divides the inside of sand box (1) into water distribution warehouse (4) and test warehouse (5), the test warehouse (5) is used to fill soil medium, the outer wall of the sand box (1) is provided with water inlet hole (6) in communication with water distribution warehouse (4), the water inlet hole (6) is in communication with water supply mechanism, the outer wall of the sand box (1) is provided with a plurality of water outlet holes (7) in communication with test warehouse (5), the top of the sand box (1) is sealingly connected with cover plate (10), a plurality of sampling holes (11) for wearing extract repair mechanism are arranged through the cover plate (10), the extract repair mechanism includes extract outer tube (13), the top of the extract outer tube (13) is movably sealingly connected with extract inner tube (16).

2. The three-dimensional sandbox modeling system for soil and groundwater multiphase extraction remediation of claim 1, wherein: The outer wall of the sand box (1) is fixedly installed with water storage box (8), the water outlet hole (7) is in communication with water storage box (8), the bottom of the water storage box (8) is provided with drain hole (9), and the drain hole (9) is in communication with water storage tank (18) through a hose.

3. The three-dimensional sandbox modeling system for soil and groundwater multiphase extraction remediation of claim 1, wherein: The outer wall of the extract inner tube (16) is provided with rubber sleeve (15), and the bottom end of the rubber sleeve (15) is located in the top opening of the extract outer tube (13).

4. The three-dimensional sandbox modeling system for soil and groundwater multiphase extraction remediation of claim 1, wherein: The bottom end of the extract outer tube (13) is blocked, and a plurality of screen holes (14) are arranged through the bottom end of the outer wall of the extract outer tube (13).

5. The three-dimensional sandbox modeling system for soil and groundwater multiphase extraction remediation of claim 1, wherein: The extract repair mechanism further includes waste liquid barrel (20), the top opening of the waste liquid barrel (20) is detachably sealingly connected with barrel cover (21), the barrel cover (21) is connected with vacuum pump through suction pipe (22), and the barrel cover (21) is in communication with the top of the extract inner tube (16) through liquid suction hose (19).

6. The three-dimensional sandbox modeling system for soil and groundwater multiphase extraction remediation of claim 1, wherein: The water supply mechanism includes peristaltic pump, the peristaltic pump is connected with water supply pipe (17), and the water outlet end of the water supply pipe (17) is in communication with water inlet hole (6).

7. The three-dimensional sandbox modeling system for soil and groundwater multiphase extraction remediation of claim 1, wherein: The sampling hole (11) is provided with rubber plug (12).

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