Ozone nano air flotation skid-mounted device for treating fracturing flow-back fluid of oil and gas field

Abstract

The utility model discloses an ozone nano air floatation skid-mounted device for treating fracturing flow-back fluid of an oil and gas field. The ozone nano air floatation skid-mounted device comprises a main body reaction tank, a dosing system, a nano bubble generation system and a nano ozone generation system, the main body reaction tank is divided into a dosing area, a release reaction area, a buffer area and a water production area according to the liquid flowing direction. According to the device, common treatment processes such as gel breaking, coagulation, oxidation and disinfection for recycling the fracturing flow-back fluid are integrated, skid-mounted equipment is formed, a recycling treatment process chain is shortened, the occupied area of the equipment is reduced, the device is suitable for an offshore platform or a special land environment, the two stages of nano-bubble generators are adopted, the number of formed nano-bubbles is larger, and the treatment efficiency is improved. The bubble size is smaller, the flocculation, oxidation and disinfection effects of ozone are further enhanced, and the treatment effect is better.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of oil and gas field waste liquid treatment, especially relates to a kind of ozone nanometer gas float skid-mounted device for treating oil and gas field fracturing flowback fluid. BACKGROUND

[0002] With the exhaustion of conventional oil and gas resources, the development of unconventional oil and gas has moved from the background to the forefront, and hydraulic fracturing is an important measure for increasing production in unconventional reservoirs. Currently, the main shale gas fracturing fluids include slickwater fracturing fluid, synthetic polymer-based fracturing fluid and guar gum-based fracturing fluid. The main organic additives include friction reducers, synthetic polymers, surfactants, clay stabilizers and bactericides, etc. During the flowback process, a large amount of rock debris, silt, bacteria, heavy metals and other substances are carried out from the formation, which are complex in composition, high in viscosity, strong in stability, high in salinity and suspended solids content, and very difficult to treat. If a large amount of fracturing flowback fluid is discharged without effective treatment, it will cause serious environmental pollution and ecological damage.

[0003] Currently, there are three main disposal methods for fracturing flowback fluid generated in oil and gas fields: reinjection into formation, discharge after treatment, and resource utilization (reuse). Reinjection into formation is the main disposal method for most flowback wastewater at present, but it is not convenient for environmental control, only temporarily controls pollution, does not fundamentally eliminate pollution, and may have more environmental safety hazards. The number of reinjection wells is decreasing year by year. Discharge after treatment is not practical because municipal wastewater treatment plants generally cannot remove total dissolved solids, high-salinity wastewater and difficult-to-degrade organic matter. Resource utilization (reuse) is to remove suspended solids, calcium and magnesium ions, bacteria and other pollutants for the preparation of fracturing fluid, achieve comprehensive utilization of water resources, eliminate environmental safety hazards, and treat flowback fluid on site and use it locally. In summary, reinjection after treatment has certain environmental risks, discharge after treatment is too expensive, and liquid preparation after treatment is the most economical and environmentally friendly fracturing fluid treatment and disposal method at present.

[0004] Currently, the resource utilization (reuse) disposal process chain basically includes oxidation, coagulation, flotation and disinfection, which is complex, occupies a large area, has high cost, and has poor effect after disposal, so there is room for improvement. SUMMARY

[0005] The utility model discloses in order to solve above-mentioned technical problem, provide a kind of ozone nanometer gas float skid-mounted device for treating oil and gas field fracturing flowback fluid.The utility model combines gas float and ozone organically, utilizes the triple function of oxidation, flocculation and disinfection of ozone gas float to treat oil field fracturing flowback fluid, and further nanometer bubble and ozone are fused to form nanometer ozone gas float technology Application to the reuse disposal of oil field fracturing flowback fluid, further improve oil and gas field fracturing flowback fluid processing effect, improve water suspended solids and organic matter removal rate and turbidity.

[0006] The utility model discloses the following technical scheme is adopted to be realized.

[0007] A kind of ozone nanometer gas float skid-mounted device for treating oil and gas field fracturing flowback fluid, including main body reaction pool, dosing system, nanometer bubble generation system and nanometer ozone generation system;

[0008] The main body reaction pool is divided into dosing area, release reaction area, buffer area and water production area according to liquid flow direction;The inside of dosing area is divided into three partitions using partition, and stirring device is arranged in three partitions;

[0009] The dosing system includes breaker reagent barrel, lye reagent barrel, flocculant reagent barrel and flocculation enhancer or coagulant aid reagent barrel, and the breaker reagent barrel is connected with the first partition of the dosing area of the main body reaction pool by dosing pump;The lye reagent barrel and the flocculant reagent barrel are connected with the second partition of the dosing area of the main body reaction pool by dosing pump respectively;The flocculation enhancer or coagulant aid reagent barrel is connected with the third partition of the dosing area of the main body reaction pool by dosing pump;

[0010] The nanometer bubble generation system includes gas dissolving pump connected with the backflow port of the buffer area of the main body reaction pool, and the gas dissolving pump is connected with gas storage tank, the gas inlet of the top of the gas storage tank is connected with air compressor, the outlet of the gas storage tank is connected with bubble cutter No.

[0011] The nanometer ozone generation system includes ozone gas dissolving pump connected with the backflow port two of the buffer area of the main body reaction pool, and the ozone gas dissolving pump is connected with bubble cutter No.

[0012] Further, the release reaction area of the main body reaction pool is provided with an inclined plate between the buffer area.

[0013] Further, the release reaction area of the main body reaction pool is provided with a sludge discharge port at the bottom.

[0014] Further, the buffer area of the main body reaction pool is provided with a slag scraper and a slag discharge port at the upper part.

[0015] Furthermore, a sludge discharge port is provided at the bottom of the buffer zone of the main reaction tank.

[0016] Furthermore, the main reaction tank has a water collection port connected to a buffer zone in the water production area, and a water production port is provided on one side of the water production area.

[0017] Furthermore, the main reaction tank has a gas collection hood at its top.

[0018] This application has the following beneficial effects.

[0019] (1) This utility model integrates the commonly used treatment processes for the reuse of fracturing flowback fluid, such as debinding, coagulation, oxidation and disinfection, and forms a skid-mounted equipment, which shortens the reuse treatment process chain, reduces the equipment footprint, and is suitable for offshore platforms or special land environments.

[0020] (2) This utility model uses a two-stage nanobubble generator to form more nanobubbles with smaller bubble size, which further enhances the flocculation, oxidation and disinfection effects of ozone and results in better treatment effect;

[0021] (3) This utility model is equipped with a VOCs collection system interface to prevent harmful gases from escaping and reduce environmental risks. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of this utility model.

[0023] Among them, 1-inlet, 2-de-gelling agent tank, 3-alkali agent tank, 4-flocculating agent tank, 5-flocculation enhancer or coagulant aid tank, 6-dosing pump one, 7-dosing pump two, 8-dosing pump three, 9-dosing pump four, 10-stirring device one, 11-stirring device two, 12-stirring device three, 13-outlet, 14-return port one, 15-dissolved air pump, 16-air storage tank one, 17-air storage tank two, 18-bubble cutter one, 19-double-headed release plate one, 20-return port two, 21-ozone dissolved air pump, 22-bubble cutter two, 23-double-headed release plate two, 24-ozone generation system, 25-air compressor, 26-sludge scraper, 27-water collection port, 28-sludge discharge port, 29-product water port; 30-main reaction tank; 31-inclined plate. Detailed Implementation

[0024] The present patent application will be further described below with reference to the embodiments.

[0025] like Figure 1 As shown, an ozone nano-flotation skid-mounted device for treating fracturing flowback fluid from oil and gas fields includes a main reaction tank 30, a chemical dosing system, a nano-bubble generating system, and a nano-ozone generating system. The main reaction tank 30 is divided into a chemical dosing zone (…). Figure 1The releasing reaction zone is indicated by "A", the buffer zone is indicated by "B", the water production zone is indicated by "C", and the adding agent zone is indicated by "D". Figure 1 The releasing reaction zone is indicated by "A", the buffer zone is indicated by "B", the water production zone is indicated by "C", and the adding agent zone is indicated by "D". Figure 1 The releasing reaction zone is indicated by "A", the buffer zone is indicated by "B", the water production zone is indicated by "C", and the adding agent zone is indicated by "D". Figure 1 The releasing reaction zone is indicated by "A", the buffer zone is indicated by "B", the water production zone is indicated by "C", and the adding agent zone is indicated by "D".

[0026] The adding agent zone is connected with the adding agent system, and is divided into three partitions by two partitions. Each partition discharges water in the form of overflow, and each partition is provided with a stirrer to ensure that the fracturing flowback fluid and the agent are fully mixed. Specifically, the first partition is used for gel breaking, and a gel breaker needs to be added. The first partition is provided with a stirrer 10, and is connected with the gel breaker agent barrel 2 through the adding agent pump 4. The second partition is used for coagulation, and alkali and flocculants need to be added. The second partition is provided with a stirrer 11, and is connected with the flocculant agent barrel 4 and the alkali agent barrel 3 through the adding agent pump 2 and the adding agent pump 3 respectively. The third partition is used for coagulation, and flocculation enhancer or coagulant aid needs to be added. The third partition is provided with a stirrer 12, and is connected with the flocculation enhancer or coagulant aid agent barrel 5 through the adding agent pump 1.

[0027] The third partition of the adding agent zone is connected with the releasing reaction zone through the overflow port (water outlet 13). The releasing reaction zone is provided with two-stage nano-bubble releasing discs. The first stage is that the backflow waste liquid is mixed with the air dissolving pump 15, and nano-sized bubbles are formed after passing through the bubble cutter 1 8 to be released in the area. The second stage is that the backflow waste liquid is mixed with ozone, and nano-sized ozone bubbles are formed after passing through the bubble cutter 2 2 to be released in the area. The nano-sized bubbles fully mix the ozone, the agent and the waste liquid to strengthen the oxidation, flocculation and disinfection effects. The releasing reaction zone is provided with a sludge discharge port at the bottom for sludge discharge.

[0028] Specifically, the double-head releasing disc 1 9 provided in the releasing reaction zone is connected with the nano-bubble generating system. The nano-bubble generating system further includes an air compressor 25, an air dissolving pump 15, a gas storage tank 1 6, a gas storage tank 1 7 and a bubble cutter 1 8. The air dissolving pump 15 is connected with the backflow port 1 4 of the buffer zone of the main reaction tank 30 to pump the backflow waste liquid into the gas storage tank. The air compressor 25 pressurizes air into the gas storage tank to mix with the waste liquid, and nano-sized bubbles are formed after passing through the bubble cutter 1 8.

[0029] The double-head releasing disc 2 3 provided in the releasing reaction zone is connected with the nano-ozone generating system. The nano-ozone generating system further includes an ozone generating system 24, an ozone dissolving pump 21 and a bubble cutter 2 2. The ozone dissolving pump 21 is connected with the backflow port 2 0 of the buffer zone of the main reaction tank 30. The ozone generated by the ozone generating system 24 and the backflow waste liquid of the ozone dissolving pump 21 form nano-sized ozone bubbles after passing through the bubble cutter 2 2.

[0030] The buffer zone of the main reaction tank 30 is provided with an inclined plate 31 for increasing the sedimentation area and shortening the particle sedimentation distance, strengthening the sedimentation effect, and the upper part of the buffer zone is provided with an automatic slag scraper 26 for removing the floating dregs, the floating dregs are discharged from the tank body through a slag discharge port 28, and two reflux ports are arranged on one side of the buffer zone for connecting the dissolved gas pump 15 and the ozone dissolved gas pump 21. The bottom of the buffer zone is provided with a sludge discharge port for discharging sludge.

[0031] The water production area of the main reaction tank 30 is provided with a water collecting port 27 connected with the buffer zone, and one side of the water production area is provided with a water outlet port 29, and the water collecting port 27 and the water outlet port 29 both adopt the overflow mode to discharge water.

[0032] The top of the main reaction tank 30 of the application is provided with a gas collecting hood to prevent the diffusion of VOCs and collect the reserved port.

[0033] The treatment process of the oil and gas field fracturing flowback fluid is as follows:

[0034] The oil and gas field fracturing flowback fluid is the waste liquid returned during the fracturing process of slick water fracturing fluid, and the main characteristic pollutants affecting reuse are suspended solids, macromolecular organic matter and bacteria. The fracturing flowback fluid enters the first partition of the dosing area through the water inlet 1, the breaker agent barrel 2 is added with the breaker agent through the dosing pump four 9, the stirrer one 10 is opened to stir to make the breaker agent mixed uniformly to complete the breaking; the waste liquid after breaking enters the second partition of the dosing area through overflow, the lye barrel 3 and the flocculant barrel 4 are added with lye and flocculant through the dosing pump three 8 and the dosing pump two 7 respectively, the stirrer two 11 is opened to stir to mix uniformly; the mixed liquid enters the third partition of the dosing area through overflow, the flocculation enhancer or coagulant aid barrel 5 is added with flocculation enhancer or coagulant aid through the dosing pump one 6, the stirrer three 12 is opened to stir to mix uniformly; the mixed liquid enters the release reaction area through the water outlet 13, after the mixed liquid fills the release reaction area and the buffer zone, at this time, the nano bubble generating system and the nano ozone generating system are both opened to work.

[0035] The dissolved gas pump 15 punches the mixed liquid from the reflux port one 14 of the buffer zone into the gas storage tank one 16 and the gas storage tank two 17, at the same time, the air compressor 25 operates to punch air into the top of the gas storage tank 16 and 17 to be mixed with the reflux waste liquid in the tank, the mixed liquid after mixing forms micro-nano bubbles through the bubble cutter one 18 and is released to the release reaction area through the double-head release disc one 19; at the same time, the ozone dissolved gas pump 21 punches the mixed liquid from the reflux port two 20 of the buffer zone into the bubble cutter two 22, at the same time, the ozone generating system 24 operates to punch ozone into the bubble cutter two 22, the ozone nano bubbles are formed through the bubble cutter two 22, and are released to the release reaction area through the double-head release disc two 23, carry the ozone nano bubbles to react with the pollutants in the waste liquid, and the oxidation, flocculation and disinfection effects are generated, the generated floating dregs are taken to the slag discharge port 28 by the slag scraper 26 for discharge, and the treated water is discharged from the water collecting port 27 into the water production area, and then discharged from the water outlet port 29.

[0036] The embodiments of the present embodiment are the preferred embodiments of the present utility model, not limited to the protection scope of the present utility model, so: all equivalent changes made according to the structure, shape, principle of the present utility model should be covered in the protection scope of the present utility model.

Claims

1. An ozone nanobubble floatation skid-mounted device for treating fracturing flowback fluid of an oil and gas field, characterized in that: The main body reaction tank (30), a dosing system, a nano-bubble generating system and a nano-ozone generating system are included. The main body reaction tank (30) is divided into a dosing area, a release reaction area, a buffer area and a water production area according to the liquid flow direction; the dosing area is internally divided into three partitions by a partition plate, and a stirrer is arranged in each partition. The dosing system includes a breaker agent barrel (2), an alkali agent barrel (3), a flocculant agent barrel (4) and a flocculation enhancer or coagulant aid agent barrel (5); the breaker agent barrel (2) is connected with the first partition of the dosing area of the main body reaction tank (30) through a dosing pump; the alkali agent barrel (3) and the flocculant agent barrel (4) are respectively connected with the second partition of the dosing area of the main body reaction tank (30) through dosing pumps; and the flocculation enhancer or coagulant aid agent barrel (5) is connected with the third partition of the dosing area of the main body reaction tank (30) through a dosing pump. The nano-bubble generating system includes a dissolved air pump (15) connected with a backflow port one (14) of the buffer area of the main body reaction tank (30); the dissolved air pump (15) is connected with a gas storage tank; an air inlet at the top of the gas storage tank is connected with an air compressor (25); an outlet of the gas storage tank is connected with a bubble cutter one (18); and an outlet of the bubble cutter one (18) is connected with a double-head release disc one (19) arranged in the release reaction area of the main body reaction tank (30). The nano-ozone generating system includes an ozone dissolved air pump (21) connected with a backflow port two (20) of the buffer area of the main body reaction tank (30); the ozone dissolved air pump (21) is connected with a bubble cutter two (22); the bubble cutter two (22) is further connected with an ozone generating system (24); and an outlet of the bubble cutter two (22) is connected with a double-head release disc two (23) arranged in the release reaction area of the main body reaction tank (30).

2. The ozone nanobubble floatation skid-mounted device for treating fracturing flowback fluid in oil and gas fields according to claim 1, characterized in that: A sloping plate (31) is arranged between the release reaction area and the buffer area of the main body reaction tank (30).

3. The ozone nanobubble floatation skid-mounted device for treating fracturing flowback fluid in oil and gas fields according to claim 1, characterized in that: A sludge discharge port is arranged at the bottom of the release reaction area of the main body reaction tank (30).

4. The ozone nanobubble floatation skid-mounted device for treating fracturing flowback fluid in oil and gas fields according to claim 1, characterized in that: A slag scraper (26) and a slag discharge port (28) are arranged at the upper part of the buffer area of the main body reaction tank (30).

5. The ozone nanobubble floatation skid-mounted device for treating fracturing flowback fluid in oil and gas fields according to claim 1, characterized in that: A sludge discharge port is arranged at the bottom of the buffer area of the main body reaction tank (30).

6. The ozone nanobubble floatation skid-mounted device for treating fracturing flowback fluid in oil and gas fields according to claim 1, characterized in that: A water collection port (27) is arranged at the buffer area of the main body reaction tank (30); and a water production port (29) is arranged at one side of the water production area of the main body reaction tank (30).

7. The ozone nanobubble floatation skid-mounted device for treating fracturing flowback fluid in oil and gas fields according to claim 1, characterized in that: A gas collecting hood is arranged at the top of the main body reaction tank (30).

Images