High-concentration calcium and magnesium waste liquid treatment device

Abstract

The utility model discloses a high-concentration calcium magnesium waste liquid treatment device which comprises a raw water tank, a sedimentation tank, a first-stage reaction device, a second-stage reaction device and a third-stage reaction device, an outlet of the raw water tank is connected with an inlet of the first-stage reaction device, an outlet of the first-stage reaction device is connected with an inlet of the second-stage reaction device, and an outlet of the third-stage reaction device is connected with an outlet of the third-stage reaction device. An outlet of the second-stage reaction device is connected with an inlet of the third-stage reaction device, and an outlet of the third-stage reaction device is connected with an inlet of the sedimentation tank. According to the device, high-concentration calcium and magnesium are fully mixed with an added medicament in the pipeline mixer, so that the reaction is more thorough, and the treatment efficiency can be remarkably improved; sampling devices are additionally arranged at all parts in the device, so that the removal effects of different reaction stages can be judged, the dosage of a medicament is convenient to analyze and adjust, the dosage and use of the medicament are optimized, and the operation cost is effectively reduced; the device is simple in structure, convenient to operate, stable and reliable in operation and suitable for treating high-concentration calcium and magnesium wastewater.

Description

Technical Field:

[0001] The utility model relates to the technical field of waste liquid treatment, in particular to a device for treating high-concentration calcium and magnesium waste liquid. Background Art:

[0002] In the extraction activities of oil and natural gas, drilling mud, fracturing flowback fluid, and gas testing operation sewage are three main sources of wastewater.

[0003] Drilling mud, as a key auxiliary material in the drilling process, with its high pH value, high concentration of soluble salts and petroleum substances, can damage the soil structure, affect the normal growth of plants, and pose a potential threat to human health through the food chain. The fracturing flowback fluid contains various chemical additives, including bactericides, clay stabilizers, hydration buffers, high-temperature stabilizers, surfactants, and stabilizers, etc. These additives, together with crude oil, inorganic additives, organic pollutants, cuttings, and clay particles, etc., make the wastewater treatment complex. The gas testing operation sewage contains oil substances, fracturing fluid, acidizing fluid, drilling fluid, minerals, gas production aids, and solids, etc., further increasing the difficulty of wastewater treatment.

[0004] These wastewaters usually have the characteristics of high turbidity, high organic matter content, and high salt content, making them the waste liquids difficult to treat in the oil and gas field exploitation process. In recent years, with the change of drilling fluid systems and the diversification of drilling types, the generated waste has become more complex, and the treatment difficulty has also increased accordingly. For example, the total amount of calcium and magnesium in the wastewater of some operating wells is extremely high, exceeding 50000mg / L, and the wastewater has a strong buffer system, which makes the conventional water treatment process difficult to effectively treat, resulting in low treatment efficiency and rising operation costs.

[0005] The current ion exchange device for treating calcium and magnesium ions in wastewater adds reagents in the transmission pipeline and finally enters the reaction container for chemical reaction and then solid-liquid separation. It is applicable to the water quality with the total amount of calcium and magnesium in the wastewater < 10000mg / L, but as the total amount of incoming calcium and magnesium increases, the treatment capacity and treatment efficiency gradually decline. The disadvantages of using this device to treat the wastewater with calcium and magnesium content > 10000mg / L are as follows: (1) As the calcium and magnesium content increases, in order to increase the reaction residence time, the water inlet volume of the device must be gradually reduced, resulting in a decrease in the treatment capacity; (2) The increase in calcium and magnesium content means that more calcium carbonate and magnesium hydroxide need to be formed, which not only increases the required reaction time but also reduces the treatment efficiency; (3) As the calcium and magnesium content increases, the density of the wastewater increases, and the free precipitation time of calcium carbonate and magnesium hydroxide also extends, further affecting the treatment efficiency. Content of the Utility Model:

[0006] To solve the above technical problems, the purpose of the present utility model is to provide a high-concentration calcium and magnesium waste liquid treatment device.

[0007] The technical solution adopted by the present utility model to solve its technical problems is a high-concentration calcium and magnesium waste liquid treatment device, which includes a raw water tank, a sedimentation tank, a first-stage reaction device, a second-stage reaction device, and a third-stage reaction device. The outlet of the raw water tank is connected to the inlet of the first-stage reaction device. The first-stage reaction device is composed of multiple groups of pipeline mixers, and adjacent two groups of pipeline mixers are connected in series through elbows. A flow regulating valve and a first chemical dosing device are respectively provided on the pipeline between the outlet of the raw water tank and the inlet of the first-stage reaction device; the outlet of the first-stage reaction device is connected to the inlet of the second-stage reaction device. The second-stage reaction device is composed of multiple groups of pipeline mixers, and adjacent two groups of pipeline mixers are connected in series through elbows. A second chemical dosing device is provided on the pipeline between the outlet of the first-stage reaction device and the inlet of the second-stage reaction device; the outlet of the second-stage reaction device is connected to the inlet of the third-stage reaction device. The third-stage reaction device is composed of at least 1 group of pipeline mixers. When the third-stage reaction device is composed of 2 groups or more of pipeline mixers, adjacent two groups of pipeline mixers are connected in series through elbows; a third chemical dosing device is provided on the pipeline between the outlet of the second-stage reaction device and the inlet of the third-stage reaction device, and the outlet of the third-stage reaction device is connected to the inlet of the sedimentation tank.

[0008] Furthermore, a first sampling device, a first one-way valve, and a cleaning pipeline outlet are also provided on the pipeline between the outlet of the raw water tank and the inlet of the first-stage reaction device. The first sampling device is arranged upstream of the first chemical dosing device, and the first one-way valve is arranged upstream of the cleaning pipeline outlet; a second sampling device is also provided on the pipeline between the outlet of the first-stage reaction device and the inlet of the second-stage reaction device. The second sampling device is arranged upstream of the second chemical dosing device; a third sampling device is also provided on the pipeline between the outlet of the second-stage reaction device and the inlet of the third-stage reaction device. The third sampling device is arranged upstream of the third chemical dosing device; a fourth sampling device, a cleaning pipeline inlet, and a second one-way valve are also provided on the pipeline between the outlet of the third-stage reaction device and the inlet of the sedimentation tank. The cleaning pipeline inlet is arranged upstream of the second one-way valve.

[0009] Furthermore, a plurality of baffles are arranged inside each group of pipeline mixers along the pipeline length direction. Each baffle is parallel to the cross-section of the pipeline mixer, and the baffle is fixedly connected to the inner wall of the pipeline mixer; there are several water conveyance holes on each baffle. The size of each baffle is one-half of the cross-sectional area of the pipeline mixer, and the latter baffle rotates 90 degrees circumferentially in the pipeline mixer relative to the former baffle.

[0010] The beneficial effects of the present utility model are as follows: This device enables high-concentration calcium and magnesium to be fully mixed with the added chemicals in the pipeline mixer, resulting in a more thorough reaction, which can significantly improve the treatment efficiency. By adding sampling devices to various parts of the device, the removal effects at different reaction stages can be judged, facilitating the analysis and adjustment of the chemical dosage, optimizing the dosing and use of chemicals, and effectively reducing the operating cost. This device has a simple structure, convenient operation, stable and reliable operation, and is suitable for treating high-concentration calcium and magnesium wastewater. Brief Description of the Drawings:

[0011] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0012] Figure 1 It is a schematic structural diagram of the present utility model.

[0013] Figure 2 It is a schematic internal structure diagram of the pipeline mixer of the present utility model.

[0014] Figure 3 It is a schematic baffle structure diagram of the pipeline mixer of the present utility model.

[0015] In the figure: raw water tank 1, sedimentation tank 2, first-stage reaction device 3, second-stage reaction device 4, third-stage reaction device 5, pipeline mixer 6, flow regulating valve 7, first chemical dosing device 8, second chemical dosing device 9, third chemical dosing device 10, first sampling device 11, first one-way valve 12, cleaning pipeline outlet 13, second sampling device 14, third sampling device 15, fourth sampling device 16, cleaning pipeline inlet 17, second one-way valve 18, baffle 19, water delivery hole 20. Specific Embodiments:

[0016] The following will clearly and completely describe the technical solutions in the embodiments of the present utility model with reference to the drawings in the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, rather than all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present utility model.

[0017] Combined with Figures 1-3As shown in the figure, the utility model is a high-concentration calcium and magnesium waste liquid treatment device, which includes a raw water tank 1, a sedimentation tank 2, a first-stage reaction device 3, a second-stage reaction device 4 and a third-stage reaction device 5. The outlet of the raw water tank 1 is connected to the inlet of the first-stage reaction device 3. The first-stage reaction device 3 is composed of 9 sets of pipe mixers 6, and the length of each set of pipe mixer 6 is 3m. Adjacent two sets of pipe mixers 6 are connected in series through elbows. On the pipeline between the outlet of the raw water tank 1 and the inlet of the first-stage reaction device 3, there are respectively a flow regulating valve 7, a first check valve 12, a cleaning pipeline outlet 13, a first sampling device 11 and a first dosing device 8. The first sampling device 11 is arranged upstream of the first dosing device 8 to ensure the accuracy of sampling. The first check valve 12 is arranged upstream of the cleaning pipeline outlet 13. The first-stage reaction device 3 composed of 9 sets of pipe mixers 6 with a length of 3m can ensure that the reagent reacts fully with the high-concentration calcium and magnesium waste liquid after being put in;

[0018] The outlet of the first-stage reaction device 3 is connected to the inlet of the second-stage reaction device 4. The second-stage reaction device 4 is composed of 9 sets of pipe mixers 6, and the length of each set of pipe mixer 6 is 3m. Adjacent two sets of pipe mixers 6 are connected in series through elbows. On the pipeline between the outlet of the first-stage reaction device 3 and the inlet of the second-stage reaction device 4, there are a second sampling device 14 and a second dosing device 9. The second sampling device 14 is arranged upstream of the second dosing device 9 to ensure the accuracy of sampling. The second-stage reaction device 4 composed of 9 sets of pipe mixers 6 with a length of 3m can ensure that the reagent reacts fully with the high-concentration calcium and magnesium waste liquid after being put in;

[0019] The outlet of the second-stage reaction device 4 is connected to the inlet of the third-stage reaction device 5. The third-stage reaction device 5 is composed of at least 1 set of pipe mixer 6. When the third-stage reaction device 4 is composed of 2 sets or more of pipe mixers 6, adjacent two sets of pipe mixers 6 are connected in series through elbows;

[0020] On the pipeline between the outlet of the second-stage reaction device 4 and the inlet of the third-stage reaction device 5, there are a third sampling device 15 and a third dosing device 10. The third sampling device 15 is arranged upstream of the third dosing device 10 to ensure the accuracy of sampling. The outlet of the third-stage reaction device 5 is connected to the inlet of the sedimentation tank 2. On the pipeline between the outlet of the third-stage reaction device 5 and the inlet of the sedimentation tank 2, there are also a fourth sampling device 16, a cleaning pipeline inlet 17 and a second check valve 18. The cleaning pipeline inlet 17 is arranged upstream of the second check valve 18 to ensure that the cleaning liquid will not enter the sedimentation tank 2. The third-stage reaction device 5 composed of 1 set of pipe mixer 6 with a length of 3m can ensure that the reagent is fully mixed with the high-concentration calcium and magnesium waste liquid after being put in.

[0021] The first sampling device 11, the second sampling device 14, the third sampling device 15, and the fourth sampling device 16 include components such as valves, sealing devices, and protective covers; the first dosing device 8, the second dosing device 9, and the third dosing device 10 include components such as dosing bins, dosing pumps, and dosing pipelines.

[0022] Inside each pipeline mixer 6, a plurality of baffles 19 are provided along the pipeline length direction. Each baffle 19 is parallel to the cross-section of the pipeline mixer 6, and the baffle 19 is fixedly connected to the inner wall of the pipeline mixer 6; there are several water delivery holes 20 on each baffle 19. The size of each baffle 19 is one-half of the cross-sectional area of the pipeline mixer 6. The latter baffle 19 rotates 90 degrees circumferentially in the pipeline mixer 6 relative to the previous baffle 19.

[0023] Working principle:

[0024] During operation, the high-concentration calcium and magnesium waste liquid is pumped out from the original water tank 1 by the waste liquid pump, and successively passes through the first-stage reaction device 3, the second-stage reaction device 4, and the third-stage reaction device 5. After the reaction, it enters the sedimentation tank 2. Liquid caustic soda is added by the first dosing device 8, and sodium carbonate solution is added by the second dosing device 9. Through the reaction in the pipeline mixer 6, magnesium hydroxide and calcium carbonate are formed. A flocculant is added by the third dosing device 10. After sufficient mixing in the pipeline mixer 6, it enters the sedimentation tank 2 for sedimentation separation. The calcium and magnesium ion concentrations in the high-concentration calcium and magnesium waste liquid are detected by the first sampling device 11 to set the treatment flow rate and the input amount of liquid caustic soda in the first dosing device 8. The waste liquid after the reaction in the first-stage reaction device 3 is detected by the second sampling device 14 to determine the reaction effect of the first-stage reaction device 3, adjust the input amount of liquid caustic soda in the first dosing device 8, and determine the input amount of sodium carbonate solution in the second dosing device 9. The waste liquid after the reaction in the second-stage reaction device 4 is detected by the third sampling device 15 to determine the reaction effect of the second-stage reaction device 4, adjust the input amount of sodium carbonate solution in the second dosing device 9. The waste liquid after the reaction in the third-stage reaction device 5 is detected by the fourth sampling device 16 to determine the reaction effect of the third-stage reaction device 5, and adjust the input amount of the flocculant in the third dosing device 10. [[ID=,10]]

[0025] The above is only the preferred embodiment of the present invention, which is only used to conveniently illustrate the present invention and does not impose any form of limitation on the present invention. Any person with ordinary knowledge in the relevant technical field, without departing from the technical features of the present invention, using the technical content disclosed by the present invention to make partial changes or modified equivalent embodiments, and without departing from the technical feature content of the present invention, still fall within the scope of the technical features of the present invention.

Claims

1. A high-concentration calcium and magnesium waste liquid treatment device, characterized in that, It includes a raw water tank, a sedimentation tank, a first-stage reaction device, a second-stage reaction device and a third-stage reaction device. The outlet of the raw water tank is connected to the inlet of the first-stage reaction device. The first-stage reaction device consists of multiple groups of pipe mixers, and adjacent two groups of pipe mixers are connected in series through elbows. A flow regulating valve and a first chemical dosing device are respectively arranged on the pipeline between the outlet of the raw water tank and the inlet of the first-stage reaction device; the outlet of the first-stage reaction device is connected to the inlet of the second-stage reaction device. The second-stage reaction device consists of multiple groups of the pipe mixers, and adjacent two groups of pipe mixers are connected in series through elbows. A second chemical dosing device is arranged on the pipeline between the outlet of the first-stage reaction device and the inlet of the second-stage reaction device; the outlet of the second-stage reaction device is connected to the inlet of the third-stage reaction device. The third-stage reaction device consists of at least 1 group of the pipe mixers. When the third-stage reaction device consists of 2 groups or more of the pipe mixers, adjacent two groups of pipe mixers are connected in series through elbows; a third chemical dosing device is arranged on the pipeline between the outlet of the second-stage reaction device and the inlet of the third-stage reaction device, and the outlet of the third-stage reaction device is connected to the inlet of the sedimentation tank.

2. The high-concentration calcium and magnesium waste liquid treatment device according to claim 1, wherein A first sampling device, a first check valve and a cleaning pipeline outlet are further arranged on the pipeline between the outlet of the raw water tank and the inlet of the first-stage reaction device. The first sampling device is arranged upstream of the first chemical dosing device, and the first check valve is arranged upstream of the cleaning pipeline outlet; a second sampling device is further arranged on the pipeline between the outlet of the first-stage reaction device and the inlet of the second-stage reaction device. The second sampling device is arranged upstream of the second chemical dosing device; a third sampling device is further arranged on the pipeline between the outlet of the second-stage reaction device and the inlet of the third-stage reaction device. The third sampling device is arranged upstream of the third chemical dosing device; a fourth sampling device, a cleaning pipeline inlet and a second check valve are further arranged on the pipeline between the outlet of the third-stage reaction device and the inlet of the sedimentation tank. The cleaning pipeline inlet is arranged upstream of the second check valve.

3. The high-concentration calcium and magnesium waste liquid treatment device according to claim 1, wherein Inside each group of pipe mixers, a plurality of baffles are arranged along the pipeline length direction. Each baffle is parallel to the cross-section of the pipe mixer, and the baffle is fixedly connected to the inner wall of the pipe mixer; there are several water delivery holes on each baffle. The size of each baffle is one-half of the cross-sectional area of the pipe mixer, and the latter baffle rotates 90 degrees circumferentially in the pipe mixer relative to the previous baffle.

Images