A geotextile clogging experiment simulation device

Abstract

The present invention provides a simulation device for geotextile clogging experiment, which includes an experimental water supply device, a reaction device and a permeation clogging device. The reaction device includes a reaction container, and a CO2 gas generator is connected to the reaction container. An exhaust port is provided at the top of the reaction container. The permeation clogging device includes a permeation tube, and a liquid inlet and a liquid outlet are provided on the permeation tube. A geotextile for separating the liquid inlet and the liquid outlet is provided inside the permeation tube. The height of the permeation tube is lower than that of the reaction container. A connecting tube with adjustable length is provided between the reaction container and the permeation tube, and a flowmeter is provided on the connecting tube. The simulation device for geotextile clogging experiment provided by the present invention uses a CO2 gas generator to introduce CO2 gas into a salt solution, and uses the adjustable length of the connecting tube to simulate the decomposition duration of HCO3 ‑ in the connecting tube. The clogging degree of the geotextile is judged by the flowmeter, and finally the mechanism and law of CO2 gas on the clogging of the geotextile are obtained, which has guiding significance for the design and selection of geotextiles in engineering.

Description

Technical Field

[0001] The present invention relates to the technical field of geotechnical engineering, and particularly to a simulation device for siltation experiments of geotextiles. Background Art

[0002] As a kind of geotechnical material, geotextiles have the advantages of low cost, corrosion resistance, convenient construction, etc., and are widely used in various projects such as coastal protection, slope reinforcement, cofferdam seepage prevention, and dam body filter. Geotextiles ensure relatively long durability with their excellent mechanical properties and internal structures. However, over time, the surface of geotextiles is blocked by soil particles and various salt crystals, resulting in siltation, thereby reducing the drainage and permeability capabilities. CO 2 As a gas with a relatively large content in space, its solubility in water is different at different temperatures. When the content of CO in water 2 is relatively high, it will combine with water to form HC0 3 - and decompose into CO during the flowing process 2- , CO 2- reacts with Ca 2+ and Mg 2+ in water to generate CaCO 3 and MgCO 3 precipitates, which aggregate to form large particles and thus block the fabric pores. There are not many research results on this at home and abroad, and the mechanism and law of siltation are not detailed. Therefore, developing an experimental device that can simulate the siltation of geotextiles under the coupling action of multiple factors is an important means to explore the siltation of geotextiles at the present stage, and it has guiding significance for the design and selection of geotextiles in engineering. Summary of the Invention

[0003] The technical problem to be solved by the present invention is: in order to overcome the deficiency that the research on the mechanism and law of CO siltation of geotextiles in the prior art is not detailed, the present invention provides a simulation device for siltation experiments of geotextiles. 2

[0004] The technical solution adopted by the present invention to solve its technical problem is: a simulation device for siltation experiments of geotextiles, including an experimental water supply device, a reaction device, and a permeation siltation device. The reaction device includes a reaction container. The experimental water supply device is used to provide experimental water with adjustable flow rate into the reaction container. A CO 2 gas inlet is connected to the reaction container for introducing CO 2 gas into the experimental water in the reaction container.A gas generator, with an exhaust port provided at the top of the reaction vessel. The penetration clogging device includes a penetration tube, which is provided with a liquid inlet and a liquid outlet. A geotextile for separating the liquid inlet and the liquid outlet is provided inside the penetration tube. The height of the penetration tube is lower than that of the reaction vessel. A connecting tube with adjustable length is provided between the reaction vessel and the penetration tube, and a flow meter is provided on the connecting tube.

[0005] The experimental water supply device is used to continuously introduce a Ca solution with the required concentration for the experiment into the reaction vessel; 2+ CO 2 The gas generator is used to uniformly introduce CO gas into the Ca solution; The Ca solution dissolved with CO gas enters the penetration tube through the connecting tube. Due to the relatively high content of CO in the water, it will combine with water to form HCO, which decomposes into CO during the co-flow process. CO reacts with Ca in the water to form CaCO precipitation, which aggregates to form large particles and thus clogs the geotextile; The clogging situation of the geotextile is judged according to the change in the reading of the flow meter on the connecting tube. 2+ solution; CO 2 gas; The Ca 2 solution dissolved with CO 2+ gas enters the penetration tube through the connecting tube. Since there is more CO in the water, it will combine with water to form HCO 2 , which decomposes into CO 3 - during the co-flow process. CO 2- reacts with Ca 2- in the water to form CaCO 2+ precipitation, and after aggregation, large particles are formed to block the geotextile; The clogging situation of the geotextile is judged according to the change in the reading of the flow meter on the connecting tube. 3 precipitate, which aggregates to form large particles and thus clogs the geotextile; The clogging situation of the geotextile is judged according to the change in the reading of the flow meter on the connecting tube.

[0006] Furthermore, the experimental water supply device includes a water storage tank, a salt solution homogenization reaction tank, and a constant water level tank. The constant water level tank is arranged above the salt solution homogenization reaction tank, and the salt solution homogenization reaction tank is arranged above the water storage tank. The height of the constant water level tank is adjustable. A first lift pump is provided in the water storage tank, and a rubber tube connecting to the salt solution homogenization reaction tank is provided at the output end of the first lift pump. A second lift pump is provided in the salt solution homogenization reaction tank, and a corrosion-resistant PE tube connecting to the constant water level tank is provided at the output end of the second lift pump.

[0007] By changing the height of the constant water level tank to change the initial head, the purpose of changing the initial flow rate is achieved. A Ca solution with the required concentration for the experiment is configured in the salt solution homogenization reaction tank, and the influence of the change in the concentration of salt ions in the salt solution homogenization reaction tank on the clogging is judged. 2+ solution, and the influence of the change in the concentration of salt ions in the salt solution homogenization reaction tank on the clogging is judged by changing the concentration of salt ions in the salt solution homogenization reaction tank.

[0008] Furthermore, it further includes an effluent recovery device. The effluent recovery device includes an effluent collection tank, an activated carbon filtration device, an RO reverse osmosis device, and a clean water tank connected in sequence. The penetration tube discharges liquid into the effluent collection tank. A water pump for pressing the liquid into the activated carbon filtration device is provided in the effluent collection tank. The liquid outlet of the clean water tank is connected to the water storage tank.

[0009] The experimental water passing through the geotextile is collected in the effluent collection tank. The experimental water in the effluent collection tank is first filtered through an activated carbon filtration device, and then deionized water is obtained by osmosis from the RO reverse osmosis device and enters the clean water tank for standby. Finally, it is sent to the storage tank for reuse, making the recycling of experimental water more environmentally friendly.

[0010] Further, valves are provided on the connecting pipe, rubber pipe, corrosion-resistant PE pipe, and CO 2 gas generator.

[0011] Further, to facilitate the replacement of the geotextile for experiments, the permeation pipe is composed of two glass pipes connected by threads. The geotextile is arranged between the two glass pipes, and a sealing ring is sleeved on the geotextile. The permeation pipe can be disassembled symmetrically, connected by threads before and after, and the geotextile is placed at the connection, and a rubber ring is added for sealing.

[0012] Further, the connecting pipe is assembled into an S-shaped pipeline by multiple plexiglass round pipes. The inner diameter of the plexiglass round pipe is 20 mm, and the outer diameter is 30 mm.

[0013] Further, the connection between the CO 2 gas generator and the reaction vessel is located 65 - 75 mm above the bottom of the reaction vessel. The gas pipe of the CO 2 gas generator extends 350 - 450 mm into the reaction vessel, and a plexiglass pipe with an inner diameter of 15 mm is inserted into the exhaust port at the top of the reaction vessel and connected to the outside.

[0014] The beneficial effects of the present invention are as follows: A geotextile clogging experiment simulation device provided by the present invention uses a CO 2 gas generator to introduce CO 2 gas into the salt solution, and uses the adjustable length of the connecting pipe to simulate the decomposition time of HCO 3 - in the connecting pipe. The clogging degree of the geotextile is judged by the flowmeter, and finally the mechanism and law of CO 2 gas on the clogging of the geotextile are obtained, which has guiding significance for the design and selection of geotextiles in engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will be further described below with reference to the drawings and embodiments.

[0016] Figure 1 is a schematic structural diagram of the best embodiment of the present invention.

[0017] In the figure: 101, storage tank; 102, salt solution homogenization reaction tank; 103, constant water level tank; 1041, first lift pump; 1042, second lift pump; 105, rubber pipe; 106, PE pipe; 201, CO 2Gas generator, 202, reaction vessel, 203, connecting pipe, 301, permeation pipe, 302, flowmeter, 303, geotextile, 401, activated carbon filtration device, 402, RO reverse osmosis device, 403, clean water tank, 405, effluent collection tank. Detailed implementation mode

[0018] The present invention will now be described in detail with reference to the accompanying drawings. This figure is a simplified schematic diagram, which only illustrates the basic structure of the present invention in a schematic manner, so it only shows the components related to the present invention.

[0019] As Figure 1 shown, a geotextile clogging experiment simulation device of the present invention includes an experimental water supply device, a reaction device and a permeation clogging device. The reaction device includes a reaction vessel 202 with a volume of 120L. The experimental water supply device is used to provide experimental water with adjustable flow rate into the reaction vessel 202. A CO 2 gas generator 201 for introducing CO 2 gas into the experimental water in the reaction vessel 202 is connected to the reaction vessel 202. The reaction vessel 202 is provided with an exhaust port at the top. The permeation clogging device includes a permeation pipe 301, and the permeation pipe 301 is provided with a liquid inlet and a liquid outlet. A geotextile 303 for separating the liquid inlet and the liquid outlet is arranged in the permeation pipe 301. The height of the permeation pipe 301 is lower than the height of the reaction vessel 202. A connecting pipe 203 with adjustable length is arranged between the reaction vessel 202 and the permeation pipe 301, and a flowmeter 302 is arranged on the connecting pipe 203.

[0020] The experimental water supply device includes a water storage tank 101, a salt solution homogenization reaction tank 102 and a constant water level tank 103. The constant water level tank 103 is arranged above the salt solution homogenization reaction tank 102, and the salt solution homogenization reaction tank 102 is arranged above the water storage tank 101. The height of the constant water level tank 103 is adjustable. A first lift pump 1041 is arranged in the water storage tank 101, and a rubber pipe 105 connected to the salt solution homogenization reaction tank 102 is arranged at the output end of the first lift pump 1041. A second lift pump 1042 is arranged in the salt solution homogenization reaction tank 102, and a corrosion-resistant PE pipe 106 connected to the constant water level tank 103 is arranged at the output end of the second lift pump 1042. The head of the first lift pump 1041 is 2m, and the inner diameter of the rubber pipe 105 is 8mm; the head of the second lift pump 1042 is 4.5m, and the inner diameter of the corrosion-resistant PE pipe 106 is 10mm.

[0021] It also includes an effluent recovery device, which includes an effluent collection tank 405, an activated carbon filtration device 401, an RO reverse osmosis device 402, and a clean water tank 403 connected in sequence. The permeation tube 301 discharges liquid into the effluent collection tank 405. A water pump for pressing liquid into the activated carbon filtration device 401 is provided in the effluent collection tank 405. The liquid outlet of the clean water tank 403 is connected to the storage tank 101. The volume of the storage tank 101 is 180L, the volume of the salt solution homogenization reaction tank 102 is 120L, the volume of the constant water level tank 103 is 100L, and the volume of the clean water tank 403 is 100L. The connecting pipe 203, the rubber tube 105, the corrosion-resistant PE tube 106, and the CO 2 valves are provided on the gas generator 201.

[0022] The permeation tube 301 is composed of two glass tubes connected by threads. The geotextile 303 is arranged between the two glass tubes, and a sealing ring is sleeved on the geotextile 303.

[0023] The connecting pipe 203 is assembled into an S-shaped pipeline by 3 organic glass round tubes of 1500mm, 4 organic glass round tubes of 200mm, 1 organic glass round tube of 1600mm, and 1 organic glass round tube of 1550mm. The inner diameter of the organic glass round tube is 20mm, and the outer diameter is 30mm.

[0024] The CO 2 connection between the gas generator 201 and the reaction vessel 202 is located 70mm above the bottom of the reaction vessel 202. The trachea of the CO 2 gas generator 201 extends 400mm into the reaction vessel 202. An organic glass tube with an inner diameter of 15mm is inserted into the exhaust port at the top of the reaction vessel 202 and connected to the outside.

[0025] Experimental procedure:

[0026] Cut the geotextile 303 required for the experiment into samples with a diameter of 210mm and place them in the permeation tube 301. The two glass tubes of the permeation tube 301 are connected by threads to fix the geotextile 303, and a sealing ring is provided at the connection of the two glass tubes. First, conduct a permeation experiment with deionized water. After the reading of the flowmeter 302 stabilizes, prepare a Ca 2+ solution with the required concentration in the salt solution homogenization reaction tank 102. Open the valve of the CO 2 gas generator 201 to keep the CO 2 gas bubbling evenly from the solution in the reaction vessel 202 at a constant speed, and then record the reading of the flowmeter 302 every 0.5h.

[0027] Experiment 1: Under the condition that other factors remain unchanged, judge the influence of the concentration of salt ions in the salt solution homogenization reaction tank 102 on the clogging of the geotextile 303;

[0028] Experiment 2: With other factors remaining unchanged, the initial water head was changed by altering the height of the constant water level tank 103 to achieve the purpose of changing the initial flow velocity, and the influence of different initial flow velocities on the clogging of the geotextile 303 was judged;

[0029] Experiment 3: With other factors remaining unchanged, by changing the length of the connecting pipe 203, the influence of the flow length of the solution on the clogging of the geotextile 303 under the action of CO 2 was explored;

[0030] Experiment 4: With other factors remaining unchanged, by changing the concentration of CO 2 generated by the CO gas generator 201, its influence on the clogging of the geotextile 303 was judged. 2

[0031] In the present invention, directions and references (such as up, down, left, right, etc.) are only used to assist in the description of the features in the drawings. Therefore, the following specific embodiments are not adopted in a restrictive sense, and the scope of the claimed subject matter is defined only by the appended claims and their equivalents.

[0032] Taking the above ideal embodiments of the present invention as an inspiration, through the above description, relevant staff can make various changes and modifications without departing from the scope of the present invention. The technical scope of this invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A geotextile clogging experiment simulation device, characterized in that: It includes an experimental water supply device, a reaction device and a penetration clogging device. The reaction device includes a reaction vessel (202). The experimental water supply device is used to provide experimental water with adjustable flow rate into the reaction vessel (202). CO 2 gas is introduced into the experimental water in the reaction vessel (202) through a CO 2 gas generator (201). The reaction vessel (202) is provided with an exhaust port at the top. The penetration clogging device includes a permeation tube (301). The permeation tube (301) is provided with a liquid inlet and a liquid outlet. A geotextile (303) for separating the liquid inlet and the liquid outlet is arranged in the permeation tube (301). The height of the permeation tube (301) is lower than that of the reaction vessel (202). A connecting tube (203) with adjustable length is arranged between the reaction vessel (202) and the permeation tube (301). A flowmeter (302) is arranged on the connecting tube (203).

2. The geotextile clogging experiment simulation device according to claim 1, characterized in that: The experimental water supply device includes a water storage tank (101), a salt solution homogenization reaction tank (102) and a constant water level tank (103). The constant water level tank (103) is arranged above the salt solution homogenization reaction tank (102), and the salt solution homogenization reaction tank (102) is arranged above the water storage tank (101). The height of the constant water level tank (103) is adjustable. A first lift pump (1041) is arranged in the water storage tank (101), and a rubber tube (105) connected to the salt solution homogenization reaction tank (102) is arranged at the output end of the first lift pump (1041). A second lift pump (1042) is arranged in the salt solution homogenization reaction tank (102), and a corrosion-resistant PE tube (106) connected to the constant water level tank (103) is arranged at the output end of the second lift pump (1042).

3. The geotextile clogging experiment simulation device according to claim 2, characterized in that: It further includes an effluent recovery device. The effluent recovery device includes an effluent collection tank (405), an activated carbon filtration device (401), an RO reverse osmosis device (402) and a clean water tank (403) connected in sequence. The permeation tube (301) discharges liquid into the effluent collection tank (405). A water pump for pressing liquid into the activated carbon filtration device (401) is arranged in the effluent collection tank (405). The liquid outlet of the clean water tank (403) is connected to the water storage tank (101).

4. The geotextile clogging experiment simulation device according to claim 2, characterized in that: The connecting pipe (203), rubber pipe (105), and corrosion-resistant PE pipe (106) are all provided with valves on the CO 2 gas generator (201).

5. The geotextile clogging experiment simulation device according to claim 1, characterized in that: The permeation tube (301) is composed of two glass tubes connected by threads. The geotextile (303) is arranged between the two glass tubes, and a sealing ring is sleeved on the geotextile (303).

6. The geotextile clogging experiment simulation device according to claim 1, characterized in that: The connecting pipe (203) is assembled into an S-shaped pipeline by multiple plexiglass round tubes. The inner diameter of the plexiglass round tube is 20 mm, and the outer diameter is 30 mm.

7. The geotextile clogging experiment simulation device according to claim 1, characterized in that: The described CO 2 The connection between the gas generator (201) and the reaction vessel (202) is located 65 to 75 mm above the bottom of the reaction vessel (202). CO 2 The gas pipe of the gas generator (201) extends 350 to 450 mm into the reaction vessel (202), and a plexiglass tube with an inner diameter of 15 mm is inserted into the exhaust port at the top of the reaction vessel (202) for connection to the outside.

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