An evaporation shed for a saline-alkali land drainage ditch and its irrigation method

Abstract

The present invention relates to an evaporation shed for a saline-alkali land drainage ditch and an irrigation method thereof. The evaporation shed includes a shed top and follow-up closing units at both ends. The shed top is of an arc-shaped structure and spans across the drainage ditch. The follow-up closing unit includes a set of vertical guide plates with floats at the bottom and a set of guide holes arranged along the arc-shaped structure at both ends of the shed top. A flexible sealing curtain is arranged between the vertical guide plates. The cross-section of the flexible sealing curtain is of an H shape, and the two vertical guide plates on both sides are respectively inserted and matched with the two grooves of the H shape. Mounting seats are arranged on both sides of the drainage ditch. The mounting seat includes an upper track and a lower collecting pipe. The track is above the ground, and the collecting pipe is below the ground. The track is provided with a water leakage groove communicated with the collecting pipe. An evaporation mechanism is also arranged inside the evaporation shed. For the irrigation method based on the above structure of the evaporation shed, it is necessary to first set up a pipeline system, then set up a database for comparing real-time data and standard samples during irrigation, and finally carry out irrigation.

Description

Technical Field

[0001] The present invention belongs to the technical field of agriculture, and particularly relates to an evaporation shed for a drainage ditch in saline-alkali land and an irrigation method therefor. Background Art

[0002] Due to the existence of urban agglomerations, the North China region is a densely populated area with a huge amount of groundwater extraction. Especially in the areas where big cities are located, multiple large groundwater funnels have been formed. Particularly in the areas near the coast, due to serious groundwater extraction, seawater intrusion has occurred, forming a part of saline-alkali land. For the crop irrigation in this part of the saline-alkali land area, a mixed irrigation method of deep fresh water and shallow brackish water is adopted. However, this method cannot effectively control the extraction amount of deep fresh water. In the prior art, usually, the proportion of deep fresh water and shallow brackish water for mixed irrigation is carried out by monitoring the soil moisture content and combining with the salinity tolerance of crops in different growth periods. However, this method still cannot relieve the situation of saline-alkali land, and the area of saline-alkali land is still slightly expanding. Therefore, how to make good use of shallow brackish water and retain deep fresh water resources is an important direction that needs further research in the saline-alkali land area. Summary of the Invention

[0003] The present invention makes up for the deficiencies of the prior art and provides an evaporation shed for a drainage ditch in saline-alkali land and an irrigation method therefor. A drainage ditch is set using the brackish water that rises upward in the saline-alkali land, and an evaporation shed is set on the drainage ditch. Fresh water evaporation and collection are carried out in the evaporation shed, and finally, it can be rationally used in combination with rainwater, brackish water, etc., and the shallow brackish water is utilized to the maximum extent to achieve crop irrigation.

[0004] The technical solution of the present invention is as follows:

[0005] An evaporation shed for a drainage ditch in saline-alkali land, the key points are that the evaporation shed includes a shed top and follow-up closing units at both ends. The shed top is an arc-shaped structure and spans across the drainage ditch. The follow-up closing unit includes a group of vertical guide plates with floats at the bottom and a group of guide holes arranged along the arc-shaped structure at both ends of the shed top. The vertical guide plates are matched with the guide holes. A flexible sealing curtain is arranged between the vertical guide plates. The upper end of the flexible sealing curtain is fixedly connected to the shed top, and the lower end is fixedly connected to the bottom of the drainage ditch. The cross-section of the flexible sealing curtain is H-shaped, and the two vertical guide plates on both sides are respectively inserted and matched with the two grooves of the H shape; mounting seats are arranged on both sides of the drainage ditch. The mounting seat includes an upper track and a lower collecting pipe. The track is above the ground, and the collecting pipe is below the ground. The track is provided with a water leakage groove communicated with the collecting pipe. A drainage plate is arranged inside the shed top, and the drainage plate is above the water leakage groove; an evaporation mechanism is also arranged in the evaporation shed.

[0006] The bottom contour of the float is the same as the bottom contour of the position where it is located in the drainage ditch.

[0007] A rainwater guiding groove is provided at the lower edge of the outer part of the shed roof, and both ends of the rainwater guiding groove extend to the ends of the shed roof.

[0008] The evaporation mechanism includes a water intake unit, a multi-layer water storage rack, and an evaporation unit. The multi-layer water storage rack includes a bracket and water storage trays arranged on the bracket with areas increasing sequentially from top to bottom. The water intake unit includes a transmission chain surrounding the bracket vertically and water intake cylinders evenly distributed on the transmission chain. When the water intake cylinder is at the bottom, the opening end of the water intake cylinder is higher than the bottom end, and the angle between the water intake cylinder and the horizontal plane is 15-30 degrees. The evaporation unit is a thermocouple arranged at the bottom of the water storage tray. The bracket is fixedly connected below the shed roof.

[0009] A high liquid level sensor and a low liquid level sensor are provided at the lower end of the bracket. A lead screw is provided below the shed roof, and a lead screw sleeve matching with the lead screw is provided on the bracket. A guide rod is also provided below the shed roof, and a guide sleeve matching with the guide rod is provided on the bracket.

[0010] For the irrigation method of the evaporation shed based on the above structure, the key point is that the irrigation method includes the following steps:

[0011] A. Set up a pipeline system

[0012] The pipeline system includes a water pump, a main pipe, branch pipes, and a water source. The water source includes a collection pipe, a pond, and a shallow well. The branch pipes are a group. One end of the main pipe is connected to the water source, and the other end is connected to the branch pipes. The water pump is installed on the main pipe. The pipeline system is provided with a CPU. EC sensors are provided at the water source, at the connection of the main pipe and the branch pipes. Solenoid valves are respectively provided at the connections of the main pipe with the collection pipe, the pond, and the shallow well. The output end of the EC sensor is connected to the signal input end of the CPU, and the signal output end of the CPU is connected to the control end of the solenoid valve.

[0013] B. Set up a database

[0014] The salt tolerance thresholds and water requirements of crops at each growth stage are input into the CPU for storage as a standard sample database.

[0015] C. Irrigation

[0016] When there is no water in the collection pipe, start the evaporation mechanism to collect fresh water. Second liquid level sensors are provided at the one-third depth position of the collection pipe and the pond. The signal output end of the second liquid level sensor is connected to the signal input end of the CPU. When either the collection pipe or the pond meets the one-third water level depth, start the water pump.

[0017] The branch pipes are drip irrigation pipes. The drip irrigation pipes are provided with spaced water outlets. The water outlets are connected to capillary tubes, and a switch valve is provided at the end of the capillary tube.

[0018] The collecting pipe is further provided with a connecting pipe, and the end of the connecting pipe accesses the pond.

[0019] The beneficial effects of the present invention are as follows:

[0020] 1) The present invention utilizes the drainage ditch in the saline-alkali land to build the evaporation shed. The end of the evaporation shed is closed to a certain extent through the follower closing unit, making it possible to condense and collect the evaporation water vapor in the evaporation shed; 2) Through the water intake, evaporation, lifting and moving of the evaporation mechanism in the evaporation shed, it is ensured that there is a certain evaporation amount in the evaporation shed; 3) The present invention makes full use of shallow slightly saline water, which can not only provide water source for evaporating fresh water, but also be mixed and used with the fresh water in the collecting pipe and the pond water, maximizing the retention of deep fresh water and meeting the growth needs of crops at each growth stage. Description of the Drawings

[0021] Figure 1 It is a schematic diagram of the end structure of the evaporation shed in the present invention.

[0022] Figure 2 It is a schematic diagram of the assembly structure of the evaporation shed and the evaporation mechanism inside it in the present invention.

[0023] Figure 3 It is Figure 2 The enlarged structure diagram of part A in

[0024] Figure 4 It is a top view of the evaporation shed in the present invention.

[0025] Figure 5 It is a schematic diagram of the structure of the water receiving tray in the present invention.

[0026] Figure 6 It is a schematic diagram of the structure of the switching valve in the present invention.

[0027] Figure 7 It is a schematic diagram of the principle of the irrigation method.

[0028] In the attached drawings, 1 is the shed roof, 101 is the plastic sheet, 102 is the support rod, 103 is the telescopic frame, 2 is the drainage ditch, 3 is the floating body, 4 is the vertical guide plate, 5 is the guide hole, 6 is the flexible sealing curtain, 7 is the track, 8 is the collecting pipe, 9 is the water leakage trough, 10 is the drainage plate, 11 is the rainwater guiding trough, 12 is the support, 13 is the water receiving tray, 14 is the transmission chain, 15 is the water intake cylinder, 16 is the thermocouple, 1701 is the high liquid level sensor, 1702 is the low liquid level sensor, 18 is the lead screw, 19 is the lead screw sleeve, 20 is the guide rod, 21 is the guide sleeve, 22 is the water pump, 23 is the main pipe, 24 is the branch pipe, 25 is the pond, 26 is the shallow well, 27 is the EC sensor, 28 is the solenoid valve, 29 is the second liquid level sensor, 30 is the water outlet, 31 is the capillary tube, 32 is the switching valve, 3201 is the rotating head, 3202 is the plug, 33 is the connecting pipe, 34 is the channel. Detailed implementation mode

[0029] The present invention relates to an evaporation shed for a saline-alkali land drainage ditch and an irrigation method thereof. The evaporation shed includes a shed roof 1 and a following closing unit at both ends. The shed roof 1 is of an arc structure and spans across the drainage ditch 2. The following closing unit includes a group of vertical guide plates 4 with floating bodies 3 at the bottom and a group of guide holes 5 arranged along the arc structure at both ends of the shed roof 1. The vertical guide plates 4 are matched with the guide holes 5. A flexible sealing curtain 6 is arranged between the vertical guide plates 4. The upper end of the flexible sealing curtain 6 is fixedly connected to the shed roof 1, and the lower end is fixedly connected to the bottom of the drainage ditch 2. The cross section of the flexible sealing curtain 6 is of an H shape, and the two vertical guide plates 4 on both sides are respectively inserted and matched with the two grooves of the H shape. Mounting seats are arranged on both sides of the drainage ditch 2. The mounting seats include an upper track 7 and a lower collecting pipe 8. The track 7 is above the ground, and the collecting pipe 8 is below the ground. The track 7 is provided with a water leakage trough 9 communicated with the collecting pipe 8. A drainage plate 10 is arranged inside the shed roof 1, and the drainage plate 10 is above the water leakage trough 9. An evaporation mechanism is also arranged inside the evaporation shed. For the irrigation method of the evaporation shed with the above structure, it is necessary to first set up a pipeline system, then set up a database for comparing real-time data and standard samples during irrigation, and finally perform irrigation. The specific structures and operation steps of the evaporation shed and the irrigation method are described through specific embodiments.

[0030] Specific embodiment. In a saline-alkali area, a drainage ditch 2 is usually set. When the shallow slightly saline water returns upward, it is discharged outside through the drainage ditch 2 to avoid returning to the surface layer, such as Figure 1As shown, the bottom contour of the floating body 3 is the same as the bottom contour of its position in the drainage ditch 2. When there is no water or little water in the drainage ditch, the floating body 3 can drive the vertical guide plate 4 to form a follow-up closing unit that matches the water surface of the drainage ditch 2, avoiding holes between the floating body 3 below the vertical guide plate 4 and the bottom surface of the drainage ditch 2, which would significantly deteriorate the closing effect. When there is more water in the drainage ditch 2, the floating body 2 drives the vertical guide plate 4 to float with the water surface to form a follow-up closing structure, preventing a large amount of water vapor in the evaporation shed from escaping.

[0031] As Figure 2 and Figure 3 shown, a rainwater guiding groove 11 is provided at the outer lower edge of the shed roof 1. The two ends of the rainwater guiding groove 11 extend to the ends of the shed roof 1. Rainwater can flow to the drainage ditch 2 along the two ends of the rainwater guiding groove 11, which can not only collect rainwater but also prevent excessive rainwater from impacting the soil at the outer edge of the shed roof 1.

[0032] When fresh water needs to be collected, it is collected through the evaporation shed. To increase the evaporation amount of water vapor, an evaporation mechanism is provided. The evaporation mechanism includes a water intake unit, a multi-layer water storage rack, and an evaporation unit. The multi-layer water storage rack includes a support 12 and water storage trays 13 arranged on the support 12 with increasing areas from top to bottom. The water intake unit includes a transmission chain 14 vertically surrounding the support 12 and water intake cylinders 15 evenly distributed on the transmission chain 14. When the water intake cylinder 15 is at the bottom, the opening end of the water intake cylinder 15 is higher than the bottom end, and the included angle between the water intake cylinder 15 and the horizontal plane is 15 - 30 degrees. The evaporation unit is a thermocouple 16 provided at the bottom of the water storage tray 13, as Figure 5 shown; the support 12 is fixedly connected below the shed roof 1; the transmission chain 14 is driven by a motor. After the water intake cylinder 15 takes water, it rotates to the topmost end, and the opening end of the water intake cylinder 15 gradually faces downward, pouring the water into the topmost water storage tray 13. After multiple pourings, the water gradually fills the upper water storage tray 13 and then overflows to the lower water storage tray 13. Water level sensors are provided at the bottoms of all the water storage trays 13. When the water level sensor of any one of the water storage trays 13 detects no water, the motor drives the transmission chain 14 to perform the water intake operation. The multi-layer water storage trays 13 increase the evaporation area, and the water vapor formed by evaporation condenses on the inner wall of the shed roof 1, flows along the arc-shaped structure to the drainage plate 10, and then enters the collection pipe 8 along the water leakage groove 9; as Figure 4 shown, the shed roof 1 is composed of a plastic cloth 101, a group of support rods 102, and a telescopic frame 103 between the support rods. The plastic cloth 101 is fixed to the inner side of the arc of the support rods 102, and the support rods 102 are exposed outside. The support rods 102 are arranged in parallel and telescoped with the help of the telescopic frame 103. The lower ends of the support rods 102 are located in the track 7 and are in sliding fit with each other. When it is necessary to maintain the internal structure of the shed roof 1 or store the evaporation shed, the support rods 102 can be pushed to slide and store. The evaporation shed is usually set to be 20 - 30 meters in length, and a passage 34 is provided between each evaporation shed to facilitate the operator to pass through the drainage ditch 2.

[0033] To adapt to different water level fluctuations, the evaporation mechanism is installed below the shed roof 1 and its height can be adjusted. At the lower end of the support 12, a high liquid level sensor 1701 and a low liquid level sensor 1702 are provided. A lead screw 18 is provided below the shed roof 1, and a lead screw sleeve 19 that cooperates with the lead screw 18 is provided on the support 12; a guide rod 20 is also provided below the shed roof 1, and a guide sleeve 21 that cooperates with the guide rod 20 is provided on the support 12. When the high liquid level sensor 1701 detects a high liquid level, the lead screw 18 rotates to drive the lead screw sleeve 19 to rise, so that the water level is lower than below the high liquid level sensor 1701. When the low liquid level sensor 1702 detects a low liquid level, the lead screw 18 rotates in the reverse direction to drive the lead screw sleeve 19 to descend, so that the water level is higher than the low liquid level sensor 1702. Such a setting is to ensure that the evaporation mechanism maintains an appropriate height relative to the water level, so that the water intake tube 15 can take water and will not penetrate into the water;

[0034] For the irrigation method of the evaporation shed with the above structure, the key point is that the irrigation method includes the following steps:

[0035] A. Set up a pipeline system

[0036] The pipeline system includes a water pump 22, a main pipe 23, branch pipes 24 and a water source. The water source includes a collection pipe 8, a pond 25 and a shallow well 26. The branch pipes 24 are a group. One end of the main pipe 23 is connected to the water source, and the other end is connected to the branch pipes 24. The water pump 22 is installed on the main pipe 23; the pipeline system is provided with a CPU. EC sensors 27 are provided at the water source, at the connection of the main pipe 23 and the branch pipes 24. Solenoid valves 28 are respectively provided at the connections of the main pipe 23 with the collection pipe 8, the pond 25 and the shallow well 26. The output end of the EC sensor 27 is connected to the signal input end of the CPU, and the signal output end of the CPU is connected to the control end of the solenoid valve 28; the branch pipes 24 are drip irrigation pipes. The drip irrigation pipes are provided with spaced water outlets 30. The water outlets 30 are connected to capillary tubes 31. A switch valve 32 is provided at the end of the capillary tube 31. As Figure 6 shown, the switch valve 32 includes a rotating head 3201 and a plug 3202. The rotating head 3201 facilitates the operator to rotate and control the opening and closing, and the plug 3202 is convenient for the operator to insert the switch valve 32 into the nearby crop planting position to improve the accuracy of water use;

[0037] B. Set up a database

[0038] Input the salt tolerance threshold and water demand of each growth period of the crop into the CPU for storage as a standard sample database;

[0039] C. Irrigation

[0040] When there is no water in the collection pipe 8, the evaporation mechanism is started to collect fresh water; a connecting pipe 33 is further provided on the collection pipe 8, and the end of the connecting pipe 33 accesses the pond 25. During the week before irrigation, after the water is collected in the collection pipe 8, it can be transported to the pond 25 along the connecting pipe 33 for irrigation use; second liquid level sensors 29 are provided at the one-third depth positions of the collection pipe 8 and the pond 25, and the signal output end of the second liquid level sensor 29 is connected to the signal input end of the CPU. When one of the collection pipe 8 and the pond 25 reaches the one-third water level depth, the water pump 22 is started for irrigation. The EC sensors 27 in the collection pipe 8 and the pond 25 transmit data to the CPU to control the opening degrees of the solenoid valves 28. The EC sensor at the connection of the main pipe 23 and the branch pipe 24 performs data feedback to correct the opening degrees of the solenoid valves 28, so that the mixed water of the water source reaches the salt tolerance threshold of the crop growth stage. This irrigation method can rationally use shallow slightly saline water. The shallow slightly saline water can not only collect water vapor through the evaporation shed, but also be used in combination with the evaporated collected fresh water and the pond water to maximize the retention of deep fresh water resources.

Claims

1. An evaporation shed for a drainage ditch in saline-alkali land, characterized in that, The evaporation shed includes a shed roof (1) and follower closing units at both ends. The shed roof (1) is an arc-shaped structure and spans across a drainage ditch (2). The follower closing unit includes a set of vertical guide plates (4) with floats (3) at the bottom and a set of guide holes (5) arranged along the arc-shaped structure at both ends of the shed roof (1). The vertical guide plates (4) cooperate with the guide holes (5). A flexible sealing curtain (6) is arranged between the vertical guide plates (4). The upper end of the flexible sealing curtain (6) is fixedly connected to the shed roof (1), and the lower end is fixed to the bottom of the drainage ditch (2). The cross-section of the flexible sealing curtain (6) is H-shaped, and the two vertical guide plates (4) on both sides are respectively inserted and matched with the two grooves of the H shape. Mounting seats are arranged on both sides of the drainage ditch (2). The mounting seat includes an upper track (7) and a lower collecting pipe (8). The track (7) is above the ground, and the collecting pipe (8) is below the ground. The track (7) is provided with a water leakage groove (9) communicating with the collecting pipe (8). A drainage plate (10) is arranged inside the shed roof (1), and the drainage plate (10) is above the water leakage groove (9). An evaporation mechanism is also arranged inside the evaporation shed.

2. The evaporation shed of a saline-alkali land drainage ditch according to claim 1, wherein, The bottom contour of the float (3) is the same as the bottom contour of the position where it is located in the drainage ditch (2).

3. The evaporation shed of a saline-alkali land drainage ditch according to claim 1, characterized in that, A rain guiding groove (11) is arranged at the outer lower edge of the shed roof (1), and both ends of the rain guiding groove (11) extend to the ends of the shed roof (1).

4. The evaporation shed for a saline-alkali land drainage ditch according to claim 1, wherein The evaporation mechanism includes a water intake unit, a multi-layer water holding rack, and an evaporation unit. The multi-layer water holding rack includes a bracket (12) and water holding trays (13) arranged on the bracket (12) and increasing in area from top to bottom. The water intake unit includes a transmission chain (14) vertically surrounding the bracket (12) and water intake cylinders (15) evenly distributed on the transmission chain (14). When the water intake cylinder (15) is at the bottom, the opening end of the water intake cylinder (15) is higher than the bottom end, and the angle between the water intake cylinder (15) and the horizontal plane is 15 - 30 degrees. The evaporation unit is a thermocouple (16) arranged at the bottom of the water holding tray (13). The bracket (12) is fixedly connected below the shed roof (1).

5. The evaporation shed of a saline-alkali land drainage ditch according to claim 4, characterized in that, A high liquid level sensor (1701) and a low liquid level sensor (1702) are arranged at the lower end of the bracket (12). A lead screw (18) is arranged below the shed roof (1), and a lead screw sleeve (19) matching the lead screw (18) is arranged on the bracket (12). A guide rod (20) is also arranged below the shed roof (1), and a guide sleeve (21) matching the guide rod (20) is arranged on the bracket (12).

6. The irrigation method of the evaporation shed according to claim 1, wherein the key point is that the irrigation method includes the following steps: A. Set up a pipeline system The pipeline system includes a water pump (22), a main pipe (23), branch pipes (24) and a water source. The water source includes a collection pipe (8), a pond (25) and a shallow well (26). The branch pipes (24) are a group. One end of the main pipe (23) is connected to the water source, and the other end is connected to the branch pipes (24). The water pump (22) is installed on the main pipe (23). The pipeline system is provided with a CPU. EC sensors (27) are provided at the connection of the water source, the main pipe (23) and the branch pipes (24). Solenoid valves (28) are respectively provided at the connections of the main pipe (23) with the collection pipe (8), the pond (25) and the shallow well (26). The output end of the EC sensor (27) is connected to the signal input end of the CPU, and the signal output end of the CPU is connected to the control end of the solenoid valve (28). B. Set up a database Input the salt tolerance thresholds and water requirements of each growth stage of the crops into the CPU for storage as a standard sample database. C. Irrigation When there is no water in the collection pipe (8), start the evaporation mechanism to collect fresh water. Second liquid level sensors (29) are provided at the one-third depth positions of the collection pipe (8) and the pond (25). The signal output end of the second liquid level sensor (29) is connected to the signal input end of the CPU. When the water level of either the collection pipe (8) or the pond (25) reaches one-third of the depth, start the water pump (22) for irrigation.

7. The irrigation method based on an evaporation shed according to claim 6, characterized in that, The branch pipes (24) are drip irrigation pipes. Spaced water outlets (30) are provided on the drip irrigation pipes. The water outlets (30) are connected to capillary tubes (31), and a switching valve (32) is provided at the end of the capillary tube (31).

8. The irrigation method based on an evaporation shed according to claim 6, wherein The collection pipe (8) is further provided with a connecting pipe (33), and the end of the connecting pipe (33) is connected to the pond (25).

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