Oil and gas wellhead sewage evaporation crystallization treatment device

Abstract

The utility model discloses an oil and gas well mouth sewage evaporation crystallization treatment device belongs to sewage treatment equipment, including evaporation crystallization jar body, is fixed with flange cover plate on evaporation crystallization jar body top, is equipped with crystallization discharge port at bottom, is equipped with frequency conversion motor on flange cover plate upper end, the output of frequency conversion motor penetrates flange cover plate and places in evaporation crystallization jar body, and is equipped with the rotary rod of fixedness at its lower end, is equipped with the stirring wing of the bottom ring circumference of rotary rod, is equipped with sewage inlet on evaporation crystallization jar body one side outer wall upper part, is equipped with steam outlet on the other side outer wall upper part, is equipped with two ultrasonic vibration rods of symmetry in the middle part of the outer wall of evaporation crystallization jar body, and the outer wall lower part of evaporation crystallization jar body is wound with electromagnetic heating coil. The device can be as solid waste or dangerous waste treatment after the mineral matter and other impurities in sewage form a small amount of crystallization through sewage evaporation crystallization treatment, so this does not need to transport, also need not to discharge, can greatly reduce the processing cost, will not cause environmental pollution.

Description

Technical Field

[0001] This utility model pertains to wastewater treatment devices, and specifically relates to a wastewater evaporation and crystallization treatment device for oil and gas wellhead wastewater. Background Technology

[0002] Currently, many oil and gas wells in China's oil extraction sector are located in remote, scattered locations with low production levels. The on-site processing of these wells generates crude oil, wastewater, and natural gas. The crude oil can be transported away by tanker trucks on a regular schedule, while the wastewater, due to environmental regulations requiring zero emissions, also needs to be transported to wastewater treatment plants on a regular schedule, resulting in high transportation and wastewater treatment costs. Furthermore, the natural gas, due to excessively high collection costs, has to be burned on-site through flares, leading to waste. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a device for treating wastewater evaporation and crystallization at oil and gas wellheads.

[0004] This utility model discloses an oil and gas wellhead wastewater evaporation and crystallization treatment device, comprising an evaporation and crystallization tank. A flange cover plate is bolted to the top of the evaporation and crystallization tank, and a crystallization outlet is located at the center of the bottom end. A variable frequency motor is located at the center of the upper end of the flange cover plate. The output end of the variable frequency motor passes through the flange cover plate and is placed inside the evaporation and crystallization tank. A rotating rod is fixed at the lower end of the motor, and stirring blades are arranged around the bottom of the rotating rod. A wastewater inlet is located on the upper part of one side of the outer wall of the evaporation and crystallization tank, and a steam outlet is located on the upper part of the other side of the outer wall. Two ultrasonic vibration rods are symmetrically arranged in the middle of the outer wall of the evaporation and crystallization tank, and an electromagnetic heating coil is wound around the lower part of the outer wall of the evaporation and crystallization tank.

[0005] As a further improvement of this utility model, a crystallization discharge valve is rotatably connected to the crystallization outlet at the bottom of the evaporation crystallization tank, a bracket is fixed on one side of the bottom of the evaporation crystallization tank, and an electric thrust rod is rotatably connected to the bottom of the bracket. The driving end of the electric thrust rod is rotatably connected to the bottom of the crystallization discharge valve.

[0006] As a further improvement of this utility model, it also includes an electromagnetic heating controller and an ultrasonic controller. The electromagnetic heating coil is electrically connected to the electromagnetic heating controller via an electromagnetic heating cable; the two ultrasonic vibration rods are electrically connected to the ultrasonic controller via an ultrasonic power cable.

[0007] As a further improvement of this utility model, it also includes a PLC control cabinet, which is electrically connected to the electromagnetic heating controller and the ultrasonic controller.

[0008] As a further improvement of this utility model, a tank temperature transmitter and an in-tank temperature transmitter are provided on the lower part of the outer wall of one side of the evaporation crystallization tank.

[0009] As a further improvement of this utility model, a radar level gauge and a temperature transmitter are provided on the flange cover plate.

[0010] As a further improvement of this utility model, a heat insulation layer is provided on the outer circumference of the evaporation crystallization tank and the upper end of the flange cover plate.

[0011] Compared with existing technologies, this utility model has the following advantages:

[0012] 1. Novelty: It has not yet been used in on-site processing devices at oil and gas wellheads;

[0013] 2. Creativity: This oil and gas wellhead wastewater evaporation and crystallization treatment device has a simple structure, compact size, safe and stable operation, and low cost;

[0014] 3. Practicality: Currently, wastewater generated by on-site oil and gas wellhead treatment units is transported to wastewater treatment plants by tanker trucks on a regular basis due to environmental protection requirements for zero discharge, resulting in high transportation and wastewater treatment costs. This new unit can treat this wastewater without requiring external transportation or discharge, thus preventing environmental pollution. The generated steam can also be used for heating the crude oil pipelines and treatment units in the on-site oil-gas-water three-phase separation process. The heated steam condenses into distilled water, which can be used for other purposes; the small amount of crystallized water can be treated as solid waste or hazardous waste, significantly reducing treatment costs.

[0015] 4. Economic efficiency: By adopting on-site sewage treatment, the high transportation costs and sewage treatment expenses of transporting sewage to other locations are saved. The generated steam and distilled condensate can also be used for the three-phase separation treatment equipment of oil, gas and water, which has certain economic benefits. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model;

[0017] Figure 2 This is a schematic diagram of the polytetrafluoroethylene coating on the convex surface of the crystallization unloading valve plate of this utility model. Detailed Implementation

[0018] This utility model discloses an evaporation and crystallization treatment device for wastewater at oil and gas wellheads, comprising an evaporation and crystallization tank 701, an electromagnetic heating controller 702, an ultrasonic controller 703, and a PLC control cabinet 706. The evaporation and crystallization tank 701 is a cylindrical container with an arc-shaped bottom. A flange cover plate 704 is bolted to the top of the evaporation and crystallization tank 701, and a crystallization outlet is located at the center of the bottom. A radar level gauge 76 and a temperature transmitter 78 are installed on the flange cover plate 704. Crystallization is welded to the bottom of the evaporation and crystallization tank 701 at the crystallization outlet. A rotating bracket 719 for the discharge valve switch is rotatably connected to a crystallization discharge valve 705. A polytetrafluoroethylene (PTFE) cladding layer 718 covers the inner convex surface of the crystallization discharge valve 705, ensuring a tight, leak-free closure. A bracket 715 is fixed to one side of the bottom of the evaporation crystallization tank 701. An electric thrust rod 716 is rotatably connected to the bottom of the bracket 715. The drive end of the electric thrust rod 716 is rotatably connected to the bottom of the crystallization discharge valve 705. Activating the electric thrust rod 716 allows for the extension or retraction of its drive end. The opening and closing of the crystallization discharge valve 705 is controlled; a variable frequency motor 72 is provided at the upper center of the flange cover plate 704, the output end of the variable frequency motor 72 passes through the flange cover plate 704 and is placed inside the evaporation crystallization tank 701, and a rotating rod 707 is fixed at its lower end. A stirring blade 708 is provided around the bottom of the rotating rod 707. When the variable frequency motor 72 is started, the rotating rod 707 and the stirring blade 708 can be driven to rotate, which can stir the liquid in the evaporation crystallization tank 701; a sewage inlet 74 is provided on the upper part of one side of the outer wall of the evaporation crystallization tank 701, and the other side of the outer wall... The upper part is provided with a steam outlet 75, and the sewage inlet 74 is connected to the sewage inlet pipeline, and an electric regulating valve 717 for liquid inlet is provided on the connecting pipeline; two ultrasonic vibration rods 79 are symmetrically provided in the middle of the outer wall of the evaporation crystallization tank 701, and the two ultrasonic vibration rods 79 are electrically connected to the ultrasonic controller 703 through ultrasonic power cable 709; an electromagnetic heating coil 73 is wound around the lower part of the outer wall of the evaporation crystallization tank 701, and the electromagnetic heating coil 73 is electrically connected to the electromagnetic heating controller 702 through electromagnetic heating cable 714.

[0019] A tank temperature transmitter 711 and an in-tank temperature transmitter 712 are provided on the lower part of the outer wall of one side of the evaporation crystallization tank 701. The tank temperature transmitter 711 is located above the electromagnetic heating coil 73, and its top probe is close to the tank body, which can monitor the tank temperature of the evaporation crystallization tank 701 in real time. The in-tank temperature transmitter 712 is inserted into the evaporation crystallization tank 701 through the temperature transmitter mounting interface welded to the tank body, which can monitor the temperature inside the evaporation crystallization tank 701 in real time.

[0020] A heat insulation layer 713 is provided around the outer wall of the evaporation crystallization tank 701 and at the upper end of the flange cover plate 704.

[0021] The PLC control cabinet 706 is electrically connected to the frequency converter motor 72, the radar level gauge 76, the temperature transmitter 78, the electromagnetic heating controller 702, the ultrasonic controller 703, the tank temperature transmitter 711, the tank internal temperature transmitter 712, and the electric push-pull rod 716.

[0022] In use, this invention first opens the electric inlet regulating valve 717, allowing wastewater to enter the evaporation crystallization tank 701 from the wastewater inlet pipe via the wastewater inlet 74. The liquid level in the tank is detected by the radar level gauge 76. As the wastewater in the tank heats and evaporates, the opening of the electric inlet regulating valve 717 is continuously adjusted to maintain the liquid level near the set value. When the liquid level in the tank is higher than that of the electromagnetic heating coil 73, the PLC control cabinet 706 controls the electromagnetic heating controller 702 to start via RS-485 communication, energizing the electromagnetic heating coil 73 to begin heating the wastewater in the tank. Simultaneously, the variable frequency motor 72 is started, causing the stirring blades 708 to stir the wastewater in the evaporation crystallization tank 701. When the PLC control cabinet 706 detects the temperature... When the temperature transmitter 78 detects that the temperature of the sewage in the tank reaches 100 degrees, steam begins to be generated. The PLC control cabinet 706 controls the heating energy of the electromagnetic heating coil 73 by adjusting the output current of the electromagnetic heating controller 702, so as to keep the evaporation rate of the sewage in the tank constant. After the electromagnetic heating controller 702 is started, the PLC control cabinet 706 starts the ultrasonic controller 703 through RS-485 communication, so that the two ultrasonic vibration rods 79 start to vibrate, ensuring that the electromagnetic heating coil 73 does not form scale on the tank wall when heating the sewage in the tank (because the sewage contains a large amount of minerals, such as calcium, magnesium and barium ions, these ions will form scale on the tank wall after heating). As the sewage in the tank is heated and evaporated, steam is output from the steam outlet pipeline 75.

[0023] The wastewater evaporation and crystallization treatment device at the oil and gas wellhead continuously inputs wastewater and generates steam. The minerals in the wastewater are continuously concentrated. When the mineral concentration reaches a certain level, the PLC control cabinet 706 closes the electric inlet regulating valve 717 to stop the inlet flow. The PLC control cabinet 706 then controls the electromagnetic heating coil 73 to continue heating. Simultaneously, the variable frequency motor 72 is started, and the stirring blades 708 agitate the water. The wastewater in the tank continuously evaporates due to the heat, and the liquid level continuously decreases. All the minerals in the wastewater will continuously crystallize. Finally, after all the water has evaporated, due to the continuous agitation of the stirring blades 708, the crystals will not form lumps but rather powder or small particles. After the water has completely evaporated, due to the electric... The magnetic heating coil 73 continues heating, but saturated steam is no longer generated inside the tank. The temperature inside the tank will rise rapidly. After the PLC control cabinet 706 detects the rapid temperature rise through the top tank temperature transmitter 78 and the bottom tank temperature transmitter 712, it immediately stops the output of the electromagnetic heating controller 73 and stops heating. At the same time, it stops the ultrasonic controller 703. After a certain period of time, when the temperature inside the tank cools down, it controls the drive end of the electric push-pull rod 716 to retract, opening the crystallization discharge valve 705 to discharge the crystals from the evaporation crystallization tank 701. After all the crystals have been discharged, the frequency converter motor 72 stops working, stops stirring, and closes the crystallization discharge valve 705. The above steps can then be restarted.

[0024] During the heating process of the electromagnetic heating coil 73, the PLC control cabinet 706 continuously monitors the temperature of the tank temperature transmitter 711. If the temperature is too low, it indicates that the electromagnetic heating controller 702 or the electromagnetic heating coil 73 is faulty and an alarm will be issued. If the temperature is too high and exceeds the set alarm limit, the output of the electromagnetic heating controller 702 will be immediately cut off and an alarm will be issued.

Claims

1. An evaporation and crystallization treatment device for oil and gas wellhead wastewater, comprising an evaporation and crystallization tank (701), characterized in that... The top of the evaporation crystallization tank (701) is fixed with a flange cover plate (704) by bolts, and a crystallization outlet is provided at the center of the bottom end. A variable frequency motor (72) is provided at the center of the upper end of the flange cover plate (704). The output end of the variable frequency motor (72) passes through the flange cover plate (704) and is placed inside the evaporation crystallization tank (701). A rotating rod (707) is fixed at its lower end. A stirring blade (708) is provided around the bottom of the rotating rod (707). A sewage inlet (74) is provided on the upper part of one side of the outer wall of the evaporation crystallization tank (701), and a steam outlet (75) is provided on the upper part of the other side of the outer wall. Two ultrasonic vibration rods (79) are symmetrically provided in the middle of the outer wall of the evaporation crystallization tank (701). An electromagnetic heating coil (73) is wound around the lower part of the outer wall of the evaporation crystallization tank (701).

2. The oil and gas wellhead wastewater evaporation and crystallization treatment device according to claim 1, characterized in that... A crystallization discharge valve (705) is rotatably connected to the crystallization outlet at the bottom of the evaporation crystallization tank (701). A bracket (715) is fixed on one side of the bottom of the evaporation crystallization tank (701). An electric push rod (716) is rotatably connected to the bottom of the bracket (715). The drive end of the electric push rod (716) is rotatably connected to the bottom of the crystallization discharge valve (705).

3. The oil and gas wellhead wastewater evaporation and crystallization treatment device according to claim 1, characterized in that... It also includes an electromagnetic heating controller (702) and an ultrasonic controller (703). The electromagnetic heating coil (73) is electrically connected to the electromagnetic heating controller (702) via an electromagnetic heating cable (714); the two ultrasonic vibration rods (79) are electrically connected to the ultrasonic controller (703) via an ultrasonic power cable (709).

4. An oil and gas wellhead wastewater evaporation and crystallization treatment device according to claim 2 or 3, characterized in that: It also includes a PLC control cabinet (706), which is electrically connected to the electromagnetic heating controller (702) and the ultrasonic controller (703).

5. The oil and gas wellhead wastewater evaporation and crystallization treatment device according to claim 1, characterized in that... The lower part of the outer wall of the evaporation crystallization tank (701) is provided with a tank temperature transmitter (711) and a tank internal temperature transmitter (712).

6. The oil and gas wellhead wastewater evaporation and crystallization treatment device according to claim 1, characterized in that: A radar level gauge (76) and a temperature transmitter (78) are provided on the flange cover plate (704).

7. The oil and gas wellhead wastewater evaporation and crystallization treatment device according to claim 1, characterized in that... The outer wall circumference of the evaporation crystallization tank (701) and the upper end of the flange cover plate (704) are provided with a heat insulation layer (713).

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