Float aeration treatment device for treating fracturing flow-back fluid

Abstract

The utility model discloses a pumice aeration treatment device for treating fracturing flow-back fluid, and aims to solve the problems that the fracturing flow-back fluid is high in viscosity and the treatment effect needs to be improved. A raw water tank, a pretreatment tank, an air floatation tank, a coagulation tank, an adsorption tank and a pumice aeration tank are sequentially arranged in the pumice aeration treatment device for treating the fracturing flow-back fluid in the water flow direction, a gel breaker is added into the pretreatment tank, a coagulant is added into the coagulation tank, a dissolved air releaser is arranged at the bottom of the air floatation tank, and the adsorption tank is arranged at the bottom of the adsorption tank. A slag scraper is arranged at the upper part of the air floatation tank, filler is stacked in the adsorption tank, pumice filler is arranged in the pumice aeration tank, and a biological membrane is attached to the pumice filler. Through gel breaking of the pretreatment tank, oil removal of the air floatation tank and coagulation of the coagulation tank, COD (chemical oxygen demand) and heavy metal content in water are greatly reduced, biodegradability is improved, and organic matters in wastewater are oxidized and decomposed by microorganisms in the pumice aeration tank, so that the treatment effect of the fracturing flow-back fluid is improved.

Description

Technical Field

[0001] The utility model relates to a water treatment device for fracturing flowback fluid in oil and gas fields. Background Technique

[0002] In oilfield development, in order to increase the production of oil and gas wells, the fracturing process is an indispensable measure and is widely used in major oilfields. However, during the fracturing operation, a large amount of flowback waste liquid will inevitably be generated. This waste liquid contains various organic and inorganic substances, as well as various additives. If directly discharged without proper treatment, it not only poses a potential threat to the environment, crops, and surface water around the well site, but may even cause serious environmental pollution problems.

[0003] On the other hand, this waste liquid discharge behavior is also a huge waste of water resources. Especially in water-scarce areas, such behavior has brought double pressure to the production and life of oilfields. Therefore, the reuse of fracturing flowback fluid can make great contributions to environmental protection, water resource conservation, and the sustainable development of oilfields. Content of the Utility Model

[0004] The utility model provides a pumice aeration treatment device for treating fracturing flowback fluid in order to solve the problems of high viscosity of fracturing flowback fluid and the need to improve the treatment effect.

[0005] The pumice aeration treatment device for treating fracturing flowback fluid of the utility model includes a raw water tank, a pretreatment tank, a flotation tank, a coagulation tank, an adsorption tank, and a pumice aeration tank. The raw water tank, pretreatment tank, flotation tank, coagulation tank, adsorption tank, and pumice aeration tank are arranged in sequence along the water flow direction. Adjacent tank bodies are connected by water pipes. A demulsifier is added to the pretreatment tank through a first chemical agent tank, and a coagulant is added to the coagulation tank through a second chemical agent tank;

[0006] A dissolved air release device is arranged at the bottom of the flotation tank, a slag scraping machine is arranged at the upper part of the flotation tank, fillers are stacked in the adsorption tank, an aeration device is arranged at the bottom of the pumice aeration tank, two layers of partition nets are arranged in the pumice aeration tank along the height direction, pumice fillers are arranged between the two layers of partition nets, and a biological film is attached to the pumice fillers.

[0007] The pumice aeration treatment device for treating fracturing fluid or fracturing flowback fluid of the utility model mainly includes a pretreatment tank, a flotation tank, a coagulation tank, and a pumice aeration tank. The pretreatment tank, flotation tank, coagulation tank, adsorption tank, and pumice aeration tank are arranged in sequence along the water flow direction. A demulsifier is added to the pretreatment tank, a dissolved air release device and a slag scraping machine are arranged in the flotation tank, the water outlet of the flotation tank is communicated with the water inlet of the coagulation tank, the water outlet of the coagulation tank is communicated with the water inlet of the adsorption tank, and the water outlet of the adsorption tank is communicated with the water inlet of the pumice aeration tank.

[0008] In the present utility model, a gel breaker is added to the pretreatment tank to perform gel breaking pretreatment on the fracturing flowback fluid, and then it flows into the air flotation tank for oil removal by air flotation. Then, a coagulant is added to the coagulation tank to cause substances such as heavy metal ions, suspended solids, and colloids in the wastewater to aggregate and precipitate. Through the adsorption of activated carbon in the adsorption tank, some heavy metal ions can also be removed, improving the biodegradability of the wastewater. The effluent from the adsorption tank enters the pumice aeration tank. Due to the aeration effect, the wastewater is fully mixed with microorganisms, strengthening the contact between the organic matter, microorganisms, and dissolved oxygen in the tank, promoting the mass transfer of oxygen, microorganisms, and wastewater, enhancing the activity of aerobic microorganisms, oxidizing and decomposing the organic matter in the wastewater, and improving the treatment effect of the fracturing flowback fluid. Brief Description of the Drawings

[0009] Figure 1 It is a schematic structural diagram of the pumice aeration treatment device for treating fracturing flowback fluid of the present utility model. Detailed Embodiments

[0010] Detailed Embodiment 1: The pumice aeration treatment device for treating fracturing flowback fluid in this embodiment includes a raw water tank 1, a pretreatment tank 2, an air flotation tank 3, a coagulation tank 4, an adsorption tank 5, and a pumice aeration tank 6. The raw water tank 1, pretreatment tank 2, air flotation tank 3, coagulation tank 4, adsorption tank 5, and pumice aeration tank 6 are arranged in sequence along the water flow direction, and adjacent tank bodies are connected by water pipes. A gel breaker is added to the pretreatment tank 2 through a first chemical agent tank 7, and a coagulant is added to the coagulation tank 4 through a second chemical agent tank 8;

[0011] A dissolved air release device 9-1 is arranged at the bottom of the air flotation tank 3, a slag scraper 10 is arranged at the upper part of the air flotation tank 3, a filler 11 is stacked in the adsorption tank 5, an aeration device 9-2 is arranged at the bottom of the pumice aeration tank 6, two layers of partition nets 13 are arranged in the pumice aeration tank 6 along the height direction, pumice fillers 12 are arranged between the two layers of partition nets 13, and biofilms are attached to the pumice fillers 12.

[0012] Detailed Embodiment 2: The difference between this embodiment and Detailed Embodiment 1 is that a stirrer 14 is arranged in the pretreatment tank 2.

[0013] Detailed Embodiment 3: The difference between this embodiment and Detailed Embodiment 1 or 2 is that the filler 11 stacked in the adsorption tank 5 is activated carbon.

[0014] Detailed Embodiment 4: The difference between this embodiment and any one of Detailed Embodiments 1 to 3 is that a stirrer 14 is arranged in the coagulation tank 4.

[0015] Detailed Embodiment 5: The difference between this embodiment and any one of Detailed Embodiments 1 to 4 is that the aeration device 9-2 is composed of an aeration disc, a connecting air pipe, and an air pump, and the air outlet of the air pump is connected to the aeration disc through the connecting air pipe.

[0016] Example: The floating rock aeration treatment device for treating fracturing flowback fluid in this example includes a raw water tank 1, a pretreatment tank 2, a flotation tank 3, a coagulation tank 4, an adsorption tank 5, and a floating rock aeration tank 6. The raw water tank 1, the pretreatment tank 2, the flotation tank 3, the coagulation tank 4, the adsorption tank 5, and the floating rock aeration tank 6 are arranged in sequence along the water flow direction. Adjacent tank bodies are connected by water pipes. A commercially available gel breaker is added to the pretreatment tank 2 through a first chemical agent tank 7, and PAC coagulant is added to the coagulation tank 4 through a second chemical agent tank 8.

[0017] A dissolved air releaser 9-1 is arranged at the bottom of the flotation tank 3, a slag scraper 10 is arranged at the upper part of the flotation tank 3, a sludge discharge trough is arranged on one side of the slag scraper 10, activated carbon fillers 11 are stacked in the adsorption tank 5, an aeration device 9-2 is arranged at the bottom of the floating rock aeration tank 6. The aeration device 9-2 is composed of an aeration disc, a connecting air pipe, and an air pump. The air outlet of the air pump is connected to the aeration disc through the connecting air pipe. Two layers of partition nets 13 are arranged in the floating rock aeration tank 6 along the height direction, and floating rock fillers 12 are arranged between the two layers of partition nets 13. Biological membranes are attached to the floating rock fillers 12, and a water outlet is opened at the upper part of the floating rock aeration tank 6.

[0018] In this example, an air compressor 16 is connected to a dissolved air tank 15. Clear water and air are mixed in the dissolved air tank 15 and then sprayed out through the dissolved air releaser 9-1.

[0019] In this example, when the total hardness of the raw fracturing flowback fluid is 3700 - 5000 mg / L, the suspended solids are 4100 - 6100 mg / L, Ca 2+ is 1350 - 2890 mg / L, and Mg 2+ is 110 - 210 mg / L, after being treated by the floating rock aeration treatment device for treating fracturing flowback fluid in this example, the total hardness of the effluent is 80 - 400 mg / L, the suspended solids are 200 - 240 mg / L, Ca 2+ is 30 - 110 mg / L, and Mg 2+ is 15 - 65 mg / L. The treatment effect is shown in Table 1 below.

[0020] Table 1

[0021]

Claims

1. A floating rock aeration treatment device for treating fracturing flowback fluid, characterized in that The pumice aeration treatment device for treating fracturing flowback fluid comprises a raw water tank (1), a pretreatment tank (2), an air flotation tank (3), a coagulation tank (4), an adsorption tank (5) and a pumice aeration tank (6); the raw water tank (1), the pretreatment tank (2), the air flotation tank (3), the coagulation tank (4), the adsorption tank (5) and the pumice aeration tank (6) are arranged in sequence along the water flow direction; adjacent tank bodies are connected by water pipes; a gel breaker is added to the pretreatment tank (2) through a first reagent tank (7); and a coagulant is added to the coagulation tank (4) through a second reagent tank (8); A dissolved air releaser (9-1) is arranged at the bottom of the flotation tank (3), a scraper (10) is arranged at the top of the flotation tank (3), a filler (11) is piled in the adsorption tank (5), an aeration device (9-2) is arranged at the bottom of the pumice aeration tank (6), two layers of partition nets (13) are arranged in the pumice aeration tank (6) along the height direction, a pumice filler (12) is arranged between the two layers of partition nets (13), and a biofilm is attached to the pumice filler (12).

2. The floating rock aeration treatment device for treating fracturing flowback fluid according to claim 1, characterized in that A stirrer (14) is arranged in the pretreatment tank (2).

3. The floating rock aeration treatment device for treating fracturing flowback fluid according to claim 1, characterized in that The filler (11) stacked in the adsorption tank (5) is activated carbon.

4. The floating rock aeration treatment device for treating fracturing flowback fluid according to claim 1, characterized in that A stirrer (14) is arranged in the coagulation tank (4).

5. The floating rock aeration treatment device for treating fracturing flowback fluid according to claim 1, characterized in that The aeration device (9-2) is composed of an aeration plate, a connecting air pipe and an air pump, and the air outlet of the air pump is connected to the aeration plate through the connecting air pipe.

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