Evaporative natural force driven soil desalination device and method
By using soil desalination devices and methods driven by natural evaporation forces, and utilizing underground irrigation and radiation evaporation technologies to separate salts from the soil, the problems of high cost and low efficiency in saline-alkali land improvement have been solved, achieving rapid and economical desalination results.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- XIAN UNIV OF TECH
- Filing Date
- 2026-04-29
- Publication Date
- 2026-06-16
AI Technical Summary
Existing methods for improving saline-alkali land are costly, inefficient, and difficult to desalinate. Furthermore, long-term and continuous management is required after improvement to prevent salinization.
The soil desalination device, driven by natural evaporation, utilizes underground irrigation technology and radiative evaporation to dissolve salts in the soil into soil water. The salts are then vaporized and separated at the soil surface by the soil water potential. Combined with sensor control and mechanical scraping, the crystallized salts are removed.
It achieves rapid and reliable desalination of saline-alkali land, reduces improvement costs and water consumption, improves desalination efficiency, and reduces the risk of salt return.
Smart Images
Figure CN122207410A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the technical field of saline-alkali soil treatment equipment, specifically to a soil desalination device driven by natural evaporation force, and also to a desalination method of the soil desalination device driven by natural evaporation force. Background Technology
[0002] For a long time, saline-alkali land improvement has formed a comprehensive technical system combining physical, chemical, biological, and agronomic methods. However, each technology has its applicable scope and limitations. In particular, chemical and physical desalination methods mostly use salt-suppressing techniques to drive salt in the soil downwards and outwards, which requires high technical investment and cost. Biological improvement is slow, with uncertain long-term effects, and is difficult to promote. In addition, soil salinization is recurrent. After saline-alkali land is improved, long-term and continuous regulation and management are necessary; otherwise, the soil can easily become saline again.
[0003] In nature, soil salts dissolve after irrigation or rainfall and, under the natural effects of radiation and evaporation, precipitate and accumulate towards the soil surface. If related technologies and methods are developed, and devices are deployed in fields to promote the dissolution of salts at different depths in the soil and accelerate surface evaporation, the accumulated salts can be collected, achieving efficient desalination and water-salt resource recovery. This would provide an innovative solution for the improvement of saline-alkali land; however, to date, no related evaporation and salt-depletion technologies and equipment have been reported. Summary of the Invention
[0004] The first objective of this invention is to provide a soil desalination device driven by natural evaporation forces to solve the problems of high cost, low efficiency, and difficulty in desalination in existing saline-alkali land improvement projects.
[0005] To achieve the first objective, the technical solution adopted by this invention is as follows: a soil desalination device driven by natural evaporation force, comprising a water source, a water pump, a main water pipe, and irrigation devices. Multiple irrigation devices are inserted into the saline-alkali soil. The multiple irrigation devices converge and are connected to the main water pipe. The main water pipe is connected to the water pump, and the water pump is installed on the main water pipe to deliver water from the water source to the irrigation devices.
[0006] Furthermore, the aforementioned soil desalination device driven by natural evaporation force also includes micro-sprinklers. Multiple micro-sprinklers are used and installed above the saline-alkali soil. Multiple micro-sprinklers are installed on micro-sprinkler irrigation pipes, which are connected to a water source through micro-sprinkler irrigation pumps.
[0007] Furthermore, the aforementioned irrigation devices can be linear irrigation devices, underground drip irrigation pipes, or seepage irrigation devices.
[0008] Furthermore, the aforementioned linear source irrigation device adopts either a first linear source irrigation device or a second linear source irrigation device. The first linear source irrigation device includes a non-woven fabric and a semi-permeable membrane. The non-woven fabric is sleeved outside the semi-permeable membrane. The water outlet end of the semi-permeable membrane is provided with a pagoda head for water discharge. The pagoda head is connected to the water supply branch pipe. The device includes an irrigation body and a connecting pipe. The irrigation body is used to irrigate the saline-alkali soil. The connecting pipe is connected to the water inlet at the top of the irrigation body and to the pagoda head. The pagoda head is connected to the water supply branch pipe.
[0009] Furthermore, a pressure compensation head is provided between the aforementioned pagoda head and the semi-permeable membrane outlet or between the pagoda head and the connecting pipe outlet.
[0010] Furthermore, sensors are installed in the aforementioned saline-alkali soil to measure the moisture and electrical conductivity of the soil.
[0011] Furthermore, water valves and water meters are also installed on the water pipes.
[0012] A soil desalination device driven by natural evaporation force, wherein the above-mentioned linear water source emitter is replaced by an underground drip irrigation pipe, and multiple underground drip irrigation pipes are used. These multiple underground drip irrigation pipes are buried in saline-alkali soil and are connected to a main water pipe after being collected.
[0013] The second objective of this invention is to provide a desalination method for a soil desalination device driven by natural evaporation forces, which can perform desalination quickly and reliably.
[0014] Regarding the second objective, the technical solution adopted by this invention is as follows: a desalination method using the aforementioned soil desalination device driven by natural evaporation force. The method involves: using an irrigation device, a combination of an irrigation device and a micro-sprinkler irrigation device, or an underground drip irrigation pipe to transport fresh water (slightly saline water) into the soil layer of saline-alkali soil, causing the salt in the soil to dissolve in the soil water. The soil water is driven to move along the soil pores and capillaries towards the soil surface using the radiation energy of the soil surface and the soil water potential. When the soil water reaches the soil surface, it vaporizes into gaseous steam when it encounters the high temperature and dry air at the ground. Meanwhile, the salt in the soil water crystallizes and remains on the soil surface due to the loss of water, thus removing the surface soil layer of the saline-alkali soil. This process is repeated multiple times to remove the surface soil layer and achieve soil desalination.
[0015] Furthermore, when soil pores and capillaries are blocked, soil water cannot move to the soil surface. In such cases, micro-sprinkler irrigation can be installed on the soil surface to wet the soil surface, allowing the surface water to infiltrate downwards and merge with the soil water supplied by the deeper irrigation devices, thus opening up the soil pores and capillary channels that allow soil water to move upwards. When a lot of salt accumulates on the soil surface, it often forms a salt crust, which reduces or even prevents the upward evaporation of water. In this case, manual or mechanical means can be used to scrape off the crystallized salt on the surface.
[0016] The beneficial effects of this invention are as follows: Compared with the prior art, this invention utilizes underground irrigation technology to dissolve the salt in the soil into soil water. It uses both the natural force of radiation evaporation and the natural force of soil water potential to drive the soil water to the soil surface. The high temperature and dry air at ground level cause the water to vaporize into gaseous steam, while the salt in the soil water crystallizes and remains on the soil surface due to the loss of water, thus separating water and salt. This solves the problems of high cost, low efficiency and incomplete desalination in existing saline-alkali land improvement methods. Attached Figure Description
[0017] Figure 1 A schematic diagram of a soil desalination device driven by natural evaporation forces;
[0018] Figure 2 A schematic diagram of a soil desalination device driven by natural evaporation forces (with micro-sprinkler irrigation system added).
[0019] Figure 3 A schematic diagram of a soil desalination device driven by natural evaporation forces (underground drip irrigation pipe).
[0020] Figure 4 This is a schematic diagram of the structure of the first-line water source emitter;
[0021] Figure 5 This is a schematic diagram of the second-line water source emitter.
[0022] Figure 6 The first day's results of a soil desalination experiment driven by natural evaporation forces;
[0023] Figure 7 The effect of the soil desalination experiment driven by the natural force of evaporation on the 30th day.
[0024] Figure label:
[0025] 1. Water source, 2. Water pump, 3. Water valve, 4. Water meter, 5. Main water pipe, 6. Irrigator, 7. Sensor, 8. Soil water flow, 9. Soil salt, 10. Soil surface crystallized salt, 11. Micro-sprinkler irrigation pump, 12. Micro-sprinkler irrigation pipe, 13. Micro-sprinkler irrigator, 14. Underground drip irrigation pipe, 61. First-line source irrigator, 62. Second-line source irrigator, 611. Non-woven fabric, 612. Semi-permeable membrane, 621. Irrigation body, 622. Connecting pipe, 63. Pressure compensation head, 64. Pagoda head. Detailed Implementation
[0026] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.
[0027] The inventive concept of this invention is to address the technical problems of "high cost, low efficiency, and difficulty in desalination in existing saline-alkali land improvement" in the prior art. This invention provides a soil desalination device driven by evaporation natural force. This device utilizes underground irrigation technology to promote the dissolution of salt in the soil into soil water. It uses both radiation evaporation natural force and soil water potential natural force to drive the soil water to the soil surface. The high temperature and dry air at the ground surface cause the water to vaporize into gaseous steam, while the salt in the soil water crystallizes and remains on the soil surface due to the loss of water, thus separating water and salt. This solves the problems of high cost, low efficiency, and incomplete desalination in existing saline-alkali land improvement. For details, please refer to Examples 1-3.
[0028] Example 1: As Figure 1-7 As shown, a soil desalination device driven by evaporation force includes a water source 1, a water pump 2, a main water pipe 5, and irrigation devices 6. Multiple irrigation devices 6 are inserted into saline-alkali soil 15. The multiple irrigation devices 6 converge and connect to the main water pipe 5, which in turn connects to the water pump 2. The water pump 2, installed on the main water pipe 5, delivers water from the water source 1 to the irrigation devices 6. Utilizing underground irrigation technology, the salts in the soil dissolve in the soil water. The soil water is driven to the soil surface by both radiative evaporation force and soil water potential force. The high temperature and dryness of the ground cause the air to vaporize into gaseous steam, while the salts in the soil water crystallize and remain on the soil surface due to water loss, thus separating water and salt. This improves the problems of high cost, low efficiency, and incomplete desalination.
[0029] Water source 1 should prioritize fresh water, but in areas where fresh water resources are very scarce, brackish water can be used instead. Water source 1 can be in various forms such as lake water, pond water, and well water.
[0030] To prevent soil water from being unable to move to the soil surface when soil pores and capillaries are blocked, micro-sprinkler irrigation can be installed on the soil surface. A soil desalination device driven by natural evaporation force also includes micro-sprinklers 13. Multiple micro-sprinklers 13 are used and are installed above the saline-alkali soil 15. Multiple micro-sprinklers 13 are installed on micro-sprinkler irrigation pipes 12. The micro-sprinkler irrigation pipes 12 are connected to the water source 1 through micro-sprinkler irrigation pumps 11. The micro-sprinklers 13 are used to wet the upper surface of the soil layer, so that the surface water infiltrates downward and merges with the soil water supplied by the deeper irrigators 6, opening up the soil pores and capillary channels for the upward movement of soil water.
[0031] The irrigation device 6 is a linear irrigation device, an underground drip irrigation pipe or a seepage irrigation device, and the linear irrigation device is either a first linear irrigation device 61 or a second linear irrigation device 62.
[0032] The first linear water source emitter 61 includes a non-woven fabric 611 and a semi-permeable membrane 612. The non-woven fabric 611 and the semi-permeable membrane 612 constitute the first linear water source emitter 61. The non-woven fabric 611 is sleeved on the outside of the semi-permeable membrane 612. The water outlet end of the semi-permeable membrane 612 is provided with a pagoda head 64 for water outlet. The pagoda head 64 is connected to the water supply branch pipe. The water supply branch pipe converges and is connected to the water pipe 5. A pressure compensation head 63 is provided between the pagoda head 64 and the water outlet end of the semi-permeable membrane 612.
[0033] The second linear source water emitter 62 includes an irrigation body 621 and a connecting pipe 622. The irrigation body 621 and the connecting pipe 622 constitute the second linear source water emitter 62. The irrigation body 621 is used to irrigate the saline-alkali soil 15. The connecting pipe 622 is connected to the water inlet at the top of the irrigation body 621. The connecting pipe 622 is connected to the pagoda head 64 through the pressure compensation head 63. The pagoda head 64 is connected to the water supply branch pipe.
[0034] Sensor 7 is installed in the saline-alkali soil 15. Sensor 7 is an integrated sensor that combines a humidity sensor and a conductivity sensor. Sensor 7 is used to measure the humidity and conductivity in the saline-alkali soil. Humidity is mainly used to control the irrigation intensity, and conductivity is mainly used to evaluate the desalination effect. Desalination is stopped when the humidity and conductivity reach the set threshold. Water valves and water meters are also installed on the water pipes to control the water supply and measure the water consumption at the corresponding locations.
[0035] Water is poured into saline-alkali soil 15 to form soil water flow 8. Soil water flow 8 carries the dissolved soil salt 9 towards the surface of saline-alkali soil 15, forming surface salt crystals 10. The surface salt crystals 10 are removed to complete the desalination process. The process of irrigating and removing surface salt crystals is repeated until the electrical conductivity of the saline-alkali soil is met, thus completing the entire desalination process.
[0036] Example 2: A soil desalination device driven by natural evaporation force. The linear irrigation device of Example 1 is replaced by an underground drip irrigation pipe 14. Multiple underground drip irrigation pipes 14 are used and buried in saline-alkali soil 15. The multiple underground drip irrigation pipes 14 are connected to the main water pipe 5 after being gathered. The rest of the structure is the same as the installation structure in Example 1.
[0037] By using underground irrigation to dissolve salts in soil at different depths, and then using natural sunlight radiation and soil water potential as driving forces, the saline water in the soil is driven to the soil surface, and the crystallized salt is manually scraped off, so as to realize the resource utilization of soil salts and solve the problems of high cost, low efficiency and difficulty in desalination in existing saline-alkali land improvement.
[0038] Example 3: A desalination method using the above-mentioned soil desalination device driven by natural evaporation force. The method is as follows: Fresh water (slightly saline water) is transported to the soil layer of saline-alkali soil by using a water irrigator, a combination of a water irrigator and a micro-sprinkler, or an underground drip irrigation pipe. This causes the salt in the soil to dissolve in the soil water. The soil water is driven to move along the soil pores and capillaries towards the soil surface by the radiation energy of the soil surface and the soil water potential. When the soil water reaches the soil surface, it vaporizes into gaseous steam when it encounters the high temperature and dry air at the ground. The salt in the soil water crystallizes and remains on the soil surface due to the loss of water, thus removing the surface soil layer of the saline-alkali soil. The removal of the surface soil layer is repeated multiple times to achieve soil desalination.
[0039] When soil pores and capillaries are blocked, soil water cannot move to the soil surface. Micro-sprinkler irrigation can be used to wet the soil surface, allowing surface water to infiltrate downwards and merge with the soil water supplied by deeper sprinklers, thus opening up the soil pores and capillary channels that allow soil water to move upwards. When a lot of salt accumulates on the soil surface, it often forms a salt crust, which reduces or even prevents water from evaporating upwards. In this case, manual or mechanical means can be used to scrape off the crystallized salt on the surface. When using underground drip irrigation pipes, multiple layers of drip irrigation pipes are laid to increase the vertical wetting area and thus increase the wetting depth of the soil layer.
[0040] This application provides a soil desalination and resource recovery technology driven by evaporation natural force. It utilizes underground irrigation technology to dissolve salts in the soil into soil water. The soil water is driven to the soil surface by both radiative evaporation natural force and soil water potential natural force. The high temperature and dry air at the ground surface cause the water to vaporize into gaseous steam, while the salts in the soil water crystallize and remain on the soil surface due to water loss, thus separating water and salts and improving the problems of high cost, low efficiency and incomplete desalination.
[0041] Table 1 compares the water consumption, desalination cycles, and duration obtained by the present invention (using a linear water source emitter) and conventional methods under the same experimental conditions.
[0042]
[0043] The specific effects of the desalination device and method are analyzed as follows:
[0044] 1) During the desalination process, the main control is whether the soil salinity reaches the target value (e.g., 3g / kg). As shown in Table 1, it takes 4 cycles to reduce 9g / kg to 3g / kg, 6 cycles to reduce 20g / kg to 3g / kg, 7 cycles to reduce 30g / kg to 3g / kg, and 8 cycles to reduce 40g / kg to 3g / kg.
[0045] 2) Regarding desalination time, compared with conventional desalination methods, as shown in Table 1, the present invention requires 120 days to reduce salt content from 9 g / kg to 3 g / kg, while conventional methods require 2-3 years; the present invention requires 180 days to reduce salt content from 20 g / kg to 3 g / kg, while conventional methods require 3-5 years; the present invention requires 210 days to reduce salt content from 30 g / kg to 3 g / kg, while conventional methods require 5-8 years; and the present invention requires 240 days to reduce salt content from 40 g / kg to 3 g / kg, while conventional methods require 5-8 years. Therefore, the present invention requires a shorter desalination time to achieve the same desalination target.
[0046] 3) Regarding water consumption, compared with conventional desalination methods, as shown in Table 1, reducing the salt concentration from 9g / kg to 3g / kg using this invention requires 720 cubic meters of water, while conventional methods, calculated at 570 cubic meters per year, require 1150-1725 cubic meters of water over 2-3 years; reducing the salt concentration from 20g / kg to 3g / kg using this invention requires 1080 cubic meters of water, while conventional methods, calculated at 1000 cubic meters per year, require 3000-5000 cubic meters of water over 3-5 years; reducing the salt concentration from 30g / kg to 3g / kg using this invention requires 1260 cubic meters of water, while conventional methods, calculated at 1400 cubic meters per year, require 7000-11200 cubic meters of water over 5-8 years; reducing the salt concentration from 40g / kg to 3g / kg using this invention requires 1440 cubic meters of water, while conventional methods, calculated at 1600 cubic meters per year, require 8000-12800 cubic meters of water over 5-8 years. Therefore, to achieve the same desalination target, this invention consumes less water.
[0047] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of protection of the claims.
Claims
1. A soil desalination device driven by natural evaporation force, characterized in that, It includes a water source, a water pump, a main water pipe, and irrigation devices. Multiple irrigation devices are used and inserted into the saline-alkali soil. The multiple irrigation devices converge and are connected to the main water pipe, which is connected to the water pump. The water pump is installed on the main water pipe to deliver water from the water source to the irrigation devices.
2. The soil desalination device driven by natural evaporation force according to claim 1, characterized in that, It also includes micro-sprinkler irrigation devices, which are used in multiples and installed above the saline-alkali soil. Multiple micro-sprinkler irrigation devices are installed on micro-sprinkler irrigation pipes, which are connected to the water source through micro-sprinkler irrigation pumps.
3. A soil desalination device driven by natural evaporation force according to claim 1 or 2, characterized in that, The irrigation devices can be linear irrigation devices, underground drip irrigation pipes, or seepage irrigation devices.
4. The soil desalination device driven by natural evaporation force according to claim 3, characterized in that, The linear source irrigation device adopts either a first linear source irrigation device or a second linear source irrigation device. The first linear source irrigation device includes a non-woven fabric and a semi-permeable membrane. The non-woven fabric is sleeved outside the semi-permeable membrane. The water outlet end of the semi-permeable membrane is equipped with a pagoda head for water discharge. The pagoda head is connected to the water supply branch pipe. The device includes an irrigation body and a connecting pipe. The irrigation body is used to irrigate the saline-alkali soil. The connecting pipe is connected to the water inlet at the top of the irrigation body and to the pagoda head. The pagoda head is connected to the water supply branch pipe.
5. The soil desalination device driven by natural evaporation force according to claim 4, characterized in that, A pressure compensation head is installed between the pagoda head and the semi-permeable membrane outlet or between the pagoda head and the connecting pipe outlet.
6. A soil desalination device driven by natural evaporation force according to claim 1 or 2, characterized in that, Sensors are installed in the saline-alkali soil to measure the moisture and electrical conductivity of the soil.
7. A soil desalination device driven by natural evaporation force according to claim 6, characterized in that, Water valves and water meters are also installed on the water pipes.
8. A soil desalination device driven by natural evaporation force according to claim 4, characterized in that, The linear irrigation system is replaced with underground drip irrigation pipes. Multiple underground drip irrigation pipes are used and buried in saline-alkali soil. The multiple underground drip irrigation pipes are then connected to the main water pipe.
9. A method for desalination using a soil desalination device driven by natural evaporation force as described in 1-2 or 8, characterized in that, The method involves using irrigation devices, a combination of irrigation devices and micro-sprinkler irrigation devices, or underground drip irrigation pipes to deliver fresh water (slightly saline water) into the soil layer of saline-alkali soil. This causes the salts in the soil to dissolve in the soil water. The soil water is then driven by the radiation energy of the soil surface and the soil water potential to move along the soil pores and capillaries towards the soil surface. When the soil water reaches the surface, it vaporizes into gaseous steam when it encounters the high temperature and dry air at the ground. Meanwhile, the salts in the soil water crystallize and remain on the soil surface due to the loss of moisture. This process removes the surface soil layer of the saline-alkali soil. The removal of the surface soil layer is repeated multiple times to desalinate the soil.
10. A soil desalination device driven by natural evaporation force according to claim 9, characterized in that, When soil pores and capillaries are blocked, soil water cannot move to the soil surface. Micro-sprinkler irrigation can be used to wet the soil surface, allowing surface water to infiltrate downwards and merge with the soil water supplied by deeper sprinklers, thus opening up the soil pores and capillary channels that allow soil water to move upwards. When a lot of salt accumulates on the soil surface, a salt crust often forms, reducing or even preventing the upward evaporation of water. In this case, manual or mechanical means can be used to scrape off the crystallized salt on the surface.