Vacuum concealed pipe circulating water salt elimination system and salt elimination method thereof

Abstract

The invention provides a vacuum concealed pipe circulating water salt elimination system which comprises a plurality of concealed pipes which are respectively connected with a water conveying pipe through a water collecting pipe; the concealed pipe comprises a pipe body, and a plurality of water collecting holes are formed in the pipe body; each water collecting pipe is provided with a vacuum negative-pressure drainage device, the water conveying pipe is connected with a salt washing water treatment device, and the water conveying pipe is provided with a water suction pump; a water outlet pipe is further connected to the salt washing water treatment device, and the water outlet pipe is connected with an irrigation leaching water distribution device used for leaching soil; the front end of the electrodialysis treatment unit is connected with a water storage tank, and the rear end of the electrodialysis treatment unit is connected with a fresh water tank. Water and air in soil are pumped out through air pumping of the vacuum pump, negative pressure is formed, and the water drainage speed in the concealed pipe salt drainage process is increased, so that the single-time salt leaching time is shortened, the salt drainage efficiency is greatly improved, the concealed pipe laying investment cost is reduced, water is saved, and water pollution caused by direct drainage of salt washing water is prevented.

Description

Technical Field

[0001] The invention belongs to the technical field of saline-alkali land management and development, and in particular relates to a vacuum dark pipe circulating water and salt removal system and a salt removal method thereof. Background Art

[0002] Saline-alkali land refers to land with more soluble salt in the soil, which is not conducive to crop growth. Freshwater flushing combined with underground pipe salt drainage is one of the traditional methods for saline-alkali land, that is, according to the law of water and salt migration, the excess water and salt in the soil are discharged by underground pipes, and the groundwater level is controlled below the critical burial depth. The underground pipe salt drainage has the advantages of saving land and effectively controlling the rise of groundwater level. It is suitable for various soil types. However, due to the large differences in the effect of salt leaching due to the buried depth and laying spacing of the underground pipes, a large amount of irrigation water and a one-time underground pipe laying investment are often required. In addition, the existing technology usually uses underground pipes and open ditches to drain salt water. The open ditch occupies a large area and wastes land; the salt discharge water is directly discharged into the surface water body, which is easy to cause water pollution; the water and soil imbalance problem in water-scarce areas further restricts the management and development and utilization of saline-alkali land. Therefore, it is necessary to design a water-saving and land-saving comprehensive management technology for saline-alkali land to achieve the economy and efficiency of underground pipe salt drainage methods. Summary of the invention

[0003] In view of this, the present invention aims to overcome the defects in the prior art and proposes a vacuum dark pipe circulating water desalination system and a desalination method thereof.

[0004] To achieve the above object, the technical solution created by the present invention is implemented as follows:

[0005] A vacuum blind pipe circulating water and salt removal system comprises a plurality of blind pipe areas arranged in the soil, wherein the plurality of blind pipes arranged in each blind pipe area are connected to a water supply pipe through a water collecting pipe; the blind pipe comprises a pipe body, on which a plurality of water collecting holes are provided; each water collecting pipe is installed with a vacuum negative pressure drainage device, the water supply pipe is connected to a brine treatment device, on which a water pump is provided; the brine treatment device is also connected with a water outlet pipe, which is connected to an irrigation and leaching water distribution device for leaching the soil; the brine treatment device comprises an electrodialysis treatment unit, the front end of which is connected to a water storage tank, and the rear end is connected to a fresh water tank.

[0006] Furthermore, the vacuum negative pressure drainage device includes a water-gas separation tank and a vacuum pump for evacuating the water-gas separation tank. The water-gas separation tank is provided with a through pipe connected to the water collecting pipe, and a drain head is provided at the bottom of the water-gas separation tank, which is connected to the water supply pipe.

[0007] Furthermore, a vacuum gauge is installed on the water-gas separation tank.

[0008] Furthermore, a venting head is provided on the upper portion of the water-gas separation tank.

[0009] Furthermore, a one-way valve is installed on the air release head.

[0010] Further, a stop valve is installed on the water discharge head.

[0011] Furthermore, the diameter of the water collection hole is 0.02-0.05 cm.

[0012] A method for removing salt using the above system comprises the following steps:

[0013] A number of groups of concealed pipes are arranged in the saline-alkali land, each group of concealed pipes is connected to the water pipe by a water collecting pipe, and a vacuum negative pressure drainage device is arranged on the water collecting pipe. The vacuum negative pressure drainage device draws air so that the moisture and air in the soil are extracted to form a negative pressure, which speeds up the drainage process of the concealed pipes. The drainage salt water extracted by the vacuum negative pressure drainage device is desalinated by the brine washing treatment device and then supplied to the irrigation and washing water distribution device through the outlet pipe to achieve recycling.

[0014] Compared with the prior art, the present invention has the following advantages:

[0015] The invention uses a vacuum pump to extract air from the soil to form a negative pressure, which speeds up the drainage speed in the process of salt drainage through the underground pipe, thereby shortening the single salt washing time. After the salt water enters the salt water treatment device for desalination treatment, it is circulated and leached on the soil again through the irrigation and leaching system, or discharged into the drainage ditch after treatment. This comprehensive management method of circulating water greatly improves the salt drainage efficiency, reduces the investment cost of underground pipe layout, saves water, and prevents water pollution caused by direct discharge of salt water. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings constituting part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0017] Figure 1 A schematic diagram of the system structure layout created by the present invention;

[0018] Figure 2 A schematic diagram of the concealed pipe part in the invention;

[0019] Figure 3 A schematic diagram of a vacuum negative pressure drainage device in the present invention;

[0020] Figure 4 The present invention is a schematic diagram of a washing brine treatment device. DETAILED DESCRIPTION

[0021] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0022] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0023] In the description of the invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the invention can be understood according to specific circumstances.

[0024] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0025] A vacuum dark pipe circulating water desalination system, such as Figures 1 to 4 As shown, it includes several concealed pipe areas 1 arranged in the soil, and several concealed pipes 3 arranged in each concealed pipe area are connected to the water pipe 6 through the water collecting pipe 4. As an example, the laying spacing of the concealed pipes 3 is 30-50m, and the laying depth is 0.8-1.0m. The concealed pipes are PE polyethylene pipes with a diameter of 30-50mm and water collecting holes at intervals of 3-5cm. The concealed pipes include a pipe body, and a plurality of water collecting holes 32 are provided on the pipe body. A vacuum negative pressure drainage device 5 is installed on each water collecting pipe, and the water conveying pipe is connected to the washing brine treatment device 8, and a water pump 7 is provided on the water conveying pipe. In an optional embodiment, the water collecting holes on the pipe body are arranged in several rows, and the angle formed by the connecting line of two adjacent rows of water collecting holes and the center of the pipe body is an acute angle. The water collecting holes are arranged crosswise to increase the water inlet area. Usually, the diameter of the water collecting holes is 0.02-0.05cm.

[0026] The outside of the pipe body of the concealed pipe is covered with a permeable geotextile 31. The permeable geotextile uses its good air permeability and water permeability to allow water to flow through, while effectively carrying soil particles, fine sand, small stones, etc. to prevent them from entering the concealed pipe and causing blockage of the water collection holes. Its good water conductivity can form a drainage channel inside the soil, which is beneficial to the discharge of excess liquid and gas in the soil structure. This drainage effect helps to move water and salt in the soil.

[0027] The washing salt water treatment device is also connected to a water outlet pipe 9, which is connected to the leaching water inlet valve 2 of the irrigation and leaching water distribution device 11 for leaching the soil. In order to better control the flow of the water outlet pipe, a flow meter 10 can be set on the water outlet pipe, and the flow meter can be used to quantitatively control the irrigation and leaching water. The washing salt water treatment device includes an electrodialysis treatment unit 82, which is connected to a reservoir 81 at the front end and a fresh water tank 84 at the rear end. In an optional embodiment, a flow meter 83 is provided on the pipeline connecting the electrodialysis treatment unit and the reservoir, and the water flow of the irrigation and leaching water distribution device is controlled by the flow meter. As an example, the water outlet pipe and the water distribution pipe of the irrigation and leaching water distribution system are selected as PVC pipes with a diameter of 50-100mm. A water outlet hole is opened on the water distribution pipe, and the diameter of the water outlet hole is 5-10mm.

[0028] The present invention is an electrodialysis system, which uses the electric field to make charged ions pass through the ion exchange membrane to separate salt from water. The treated brine enters the freshwater pool for temporary storage. The freshwater pool is connected to the outlet pipe, and the reservoir is connected to the water pipe. At the same time, an overflow pipe 12 is provided on the freshwater pool, and the drain outlet end of the overflow pipe extends to the drain ditch 13. When there is too much water in the freshwater pool, the water in the freshwater pool is allowed to overflow into the drain ditch.

[0029] The vacuum negative pressure drainage device includes a water-gas separation tank 52 and a vacuum pump 53 for evacuating the water-gas separation tank. The water-gas separation tank is provided with a through pipe 51 connected to the water collecting pipe, and a water discharge head 56 is provided at the lower part of the water-gas separation tank, and the water discharge head is connected to the water pipe. Usually, a vacuum gauge 54 is installed on the water-gas separation tank. A vent head 55 is provided at the upper part of the water-gas separation tank. As an example, a one-way valve is installed on the vent head, and the gas in the water-gas separation tank is discharged to the outside. A stop valve is installed on the vent head, which can be closed or opened as needed.

[0030] The vacuum pumps of several vacuum negative pressure drainage devices are used to evacuate air, and negative pressure (negative pressure not less than 80Kpa) is quickly formed in each dark pipe area of ​​the treatment unit. The vacuum degree is displayed on the vacuum gauge (the range of the vacuum gauge should be less than -0.1MPa). The vacuum pump negative pressure drainage device accelerates the movement of salt water to the dark pipe. The salt water and gas in the soil enter the water-gas separation tank through the water collecting pipe and the through pipe. The gas is discharged through the venting head. The washing salt water is connected to the water pipe through the water discharge head and enters the washing salt water treatment device through the pumping pump. Usually, the pumping pump flow rate is not less than 10m3 / h.

[0031] A method for removing salt using the vacuum dark pipe circulating water removal system comprises the following steps:

[0032] Several groups of concealed pipes are set up in the saline-alkali land, each group of concealed pipes is connected to the water pipe by a water collecting pipe, and a vacuum negative pressure drainage device is arranged on the water collecting pipe. The vacuum negative pressure drainage device draws air to draw out the moisture and air in the soil, forming a negative pressure, which speeds up the drainage process of the concealed pipe. The brine extracted by the vacuum negative pressure drainage device is desalinated by the brine washing treatment device and then supplied to the irrigation, washing and water distribution device through the outlet pipe to realize recycling and achieve the purpose of water saving. Moreover, the treated brine is recycled or discharged into the drainage ditch, which can effectively prevent surface water pollution.

[0033] The invention uses vacuum negative pressure technology to increase the hydraulic gradient and increase the pumping efficiency, thereby improving the drainage efficiency of the underground pipe salt drainage, reducing the salt washing time, and significantly improving the salt washing efficiency. Due to the increase in the hydraulic gradient between the underground pipe and the surface, the horizontal influence range of the underground pipe increases, so the spacing between the underground pipes can be appropriately increased, which can reduce the use of pipes and reduce the cost of laying underground pipes. The salt water treatment device is used to treat the salt water and then discharge or recycle it, which helps to protect water resources and reduce environmental pollution. In summary, the invention combines the technology of underground pipe salt drainage, vacuum negative pressure and water desalination to adapt to different types of saline-alkali land and improve the flexibility and applicability of governance. By reducing the salt washing time and reducing the cost of underground pipes, this combined technology can reduce the overall governance cost and improve economic benefits.

[0034] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A vacuum dark pipe circulating water desalination system, Features: It includes several concealed pipe areas arranged in the soil, and several concealed pipes arranged in each concealed pipe area are connected to the water pipe through the water collecting pipe respectively; the concealed pipe includes a pipe body, and the pipe body is provided with a plurality of water collecting holes; each water collecting pipe is installed with a vacuum negative pressure drainage device, the water pipe is connected with the washing salt water treatment device, and the water pipe is provided with a water pump; the washing salt water treatment device is also connected with a water outlet pipe, and the water outlet pipe is connected with the irrigation and washing water distribution device used for leaching the soil; the washing salt water treatment device includes an electrodialysis treatment unit, and the front end of the electrodialysis treatment unit is connected to the water storage tank, and the rear end is connected to the fresh water tank.

2. A vacuum dark pipe circulating water desalination system according to claim 1, Features: The vacuum negative pressure drainage device includes a water-gas separation tank and a vacuum pump for evacuating the water-gas separation tank. The water-gas separation tank is provided with a through pipe connected to a water collecting pipe, and a drain head is provided at the bottom of the water-gas separation tank, which is connected to a water delivery pipe.

3. A vacuum dark pipe circulating water desalination system according to claim 2, Features: A vacuum gauge is installed on the water-gas separation tank.

4. A vacuum dark pipe circulating water desalination system according to claim 2, Features: A venting head is provided on the top of the water-gas separation tank.

5. A vacuum dark pipe circulating water desalination system according to claim 4, Features: A one-way valve is installed on the air bleed head.

6. A vacuum dark pipe circulating water desalination system according to claim 2, Features: A stop valve is installed on the drain head.

7. A vacuum dark pipe circulating water desalination system according to claim 1, Features: The diameter of the water collection hole is 0.02-0.05cm.

8. A method for removing salt using the system according to any one of claims 1 to 7, It is characterized in that The steps include: A number of groups of concealed pipes are arranged in the saline-alkali land, each group of concealed pipes is connected to the water pipe by a water collecting pipe, and a vacuum negative pressure drainage device is arranged on the water collecting pipe. The vacuum negative pressure drainage device draws air so that the moisture and air in the soil are extracted to form a negative pressure, which speeds up the drainage process of the concealed pipes. The drainage salt water extracted by the vacuum negative pressure drainage device is desalinated by the brine washing treatment device and then supplied to the irrigation and washing water distribution device through the outlet pipe to achieve recycling.

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