Wellhead flowback fluid desulfurization system

Abstract

The invention discloses a wellhead flow-back fluid desulfurization system which comprises a mixing stirrer and three agent storage tanks, and the mixing stirrer is connected with the agent storage tanks storing corresponding agents through independent agent filling pipes; each medicament storage tank is connected in parallel between the feeding header pipe and the discharging header pipe through a feeding pipe arranged at the upper part and a discharging pipe arranged at the lower part; a feeding pipe of each medicament storage tank is provided with a feeding valve, a discharging pipe of each medicament storage tank is provided with a discharging valve, and gear pumps are mounted at an inlet of a main feeding pipe and an outlet of a main discharging pipe; the mixing stirrer is respectively connected with a flowback fluid input pipe and a tail water discharge pipe; a pH value detection sensor and a sulfide detection sensor are further mounted on the tail water discharge pipe. According to the method, efficient harmless treatment of the high-sulfur-content wellhead flow-back fluid is achieved, the problems of environmental pollution, high operation risk and dependence on manual operation in the traditional technology are solved, and the method is particularly suitable for complex working conditions after acid fracturing of marine carbonate reservoirs.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental protection equipment, in particular to a wellhead flowback fluid desulfurization system. Background Art

[0002] Marine reservoirs (carbonate reservoirs) contain high levels of toxic gases such as hydrogen sulfide and sulfur dioxide. Acidizing and fracturing are generally required to increase reserves and production in these reservoirs. The post-acidizing drainage process of sulfur-containing wells also produces high concentrations of HCl gas. Existing drainage technologies cannot effectively treat the toxic gases, which can only diffuse into the air, posing serious safety risks and environmental pollution. Therefore, equipment that can process and regulate wellhead flowback fluids for such complex testing operations is urgently needed to achieve harmless treatment of the wellhead discharge fluid and protect the ecological environment. Summary of the Invention

[0003] The purpose of the present invention is to provide a wellhead flowback fluid desulfurization system with complete functions, simple operation, convenient installation, and high degree of automation, which meets the requirements of real-time treatment of wellhead discharge fluid in field oil and gas on-site ground testing operations.

[0004] The present invention is achieved through the following technical solutions: a wellhead flowback liquid desulfurization system, comprising a mixing agitator for treating wellhead flowback liquid and three chemical storage tanks for storing a desulfurizer, a neutralizer and a defoaming agent respectively, the mixing agitator being connected to the chemical storage tanks storing the corresponding chemicals through independent chemical filling pipes; each of the chemical storage tanks is connected in parallel between a feed main pipe and a discharge main pipe through a feed pipe arranged at the upper part and a discharge pipe arranged at the lower part; the feed pipe of each chemical storage tank is provided with a feed valve, and the discharge pipe is provided with a discharge valve, and gear pumps are installed at the inlet of the feed main pipe and the outlet of the discharge main pipe; the mixing agitator is respectively connected to a flowback liquid input pipe and a tail water discharge pipe; a pH value detection sensor and a sulfide detection sensor are also installed on the tail water discharge pipe.

[0005] In order to better implement the present invention, further, two spare pipelines are provided in parallel between the feed main pipe and the discharge main pipe, and a spare valve is provided between each spare pipeline.

[0006] In order to better implement the present invention, further, each of the drug storage tanks is also provided with a waste pipe and a liquid level meter, each of the waste pipes is connected to a waste main pipe, each of the waste pipes is provided with a waste valve, and the waste main pipe is provided with a waste main valve.

[0007] In order to better realize the present invention, the pressure relief pipe is further provided with a safety pressure relief reflux pipe, and the safety pressure relief reflux pipes of different medicine storage tanks are connected with the corresponding medicine filling pipes of the medicine storage tanks, and each of the safety pressure relief reflux pipes is also provided with a safety valve.

[0008] In order to better implement the present invention, further, each of the drug storage tanks is also provided with a forced pressure relief reflux pipe connected to the corresponding safety pressure relief reflux pipe, and each of the forced pressure relief reflux pipes is also provided with a forced pressure relief valve.

[0009] In order to better implement the present invention, further, each of the drug filling pipes is provided with a diaphragm metering pump, a pressure sensor, and a one-way valve.

[0010] In order to better realize the present invention, further, the return liquid input pipe, tail water discharge pipe, each reagent filling pipe, feed main pipe, and unloading main pipe are all provided with independent electric valves, the feed main pipe is also provided with a feed main valve, and the unloading main pipe is also provided with a unloading main valve.

[0011] In order to better realize the present invention, it further includes a control system, which receives tail water information fed back by the pH detection sensor and the sulfide detection sensor, the agent liquid level information in the corresponding agent storage tank fed back by each liquid level meter, and the agent flow and hydraulic information in the corresponding agent filling pipe fed back by each diaphragm metering pump and pressure sensor; and controls the feed valve, discharge valve, main feed valve, main discharge valve, and electric valve of each pipeline through the received information, so that the tail water finally flowing out of the mixing agitator meets the purification standards.

[0012] In order to better implement the present invention, it further includes a skid body that accommodates all the medicine storage tanks and corresponding pipelines and valves and seals them.

[0013] In order to better implement the present invention, a line bridge for controlling system wiring is further provided in the skid body.

[0014] Compared with the prior art, the present invention has the following advantages and beneficial effects: Through automated control, modular design, multiple safety protections, and intelligent feedback regulation, the present invention achieves efficient and harmless treatment of high-sulfur wellhead flowback fluid, solving the pain points of traditional technologies such as environmental pollution, high operational risks, and reliance on manual operation. It is particularly suitable for complex working conditions after acidizing and fracturing of marine carbonate reservoirs, and has significant technological advancement and engineering practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings: Figure 1 It is a schematic block diagram of the workflow structure of the present invention; Figure 2 It is a schematic diagram of the three-dimensional structure of the present invention; Figure 3 Schematic diagram of the three-dimensional structure of the feeding mechanism of the present invention; Figure 4 Schematic diagram of the three-dimensional structure of the unloading mechanism of the present invention; Figure 5 Schematic diagram of the three-dimensional structure of the feed main pipe and the discharge main pipe serving as backup for each other in the present invention; Figure 6 Schematic diagram of the three-dimensional structure of the medicine storage tank of the present invention; Figure 7 Schematic diagram of the three-dimensional structure of the neutralizer tank in the present invention; Figure 8 It is a partial three-dimensional structural diagram of the filling mechanism in the present invention; Figure 9 It is a schematic diagram of the overall three-dimensional structure of the filling mechanism of the present invention; Figure 10 A top view of the waste discharge mechanism of the present invention; Figure 11 Schematic diagram of the three-dimensional structure of the line bridge of the control system of the present invention; Figure 12 Schematic diagram of the three-dimensional structure of the skid body in the present invention; Figure 13 A top view of the mixer skid of the present invention Figure 14 This is a top view of the pH detection skid of the present invention.

[0016] Among them: 1-defoaming tank feed valve, 2-desulfurization tank feed valve, 3-neutralization tank feed valve, 4-feed gear pump, 5-electromagnetic control feed valve, 6-feed main pipe, 7-feed main valve, 8-defoaming tank discharge valve, 9-desulfurization tank discharge valve, 10-neutralization tank discharge valve, 11-discharge gear pump, 12-electromagnetic control discharge valve, 13-discharge main pipe, 14-discharge main valve, 15-first spare pipe, 16-second spare pipe, 17-first spare valve, 18-second spare valve, 19-tank body, 20-top surface inspection manhole, 21-feed port, 22-explosion-proof and fire-retardant breathing valve, 23-safety pressure relief reflux port, 24-forced pressure relief reflux port, 25-manual ball valve, 26-magnetic flap level gauge, 27-side inspection manhole, 28-drug Agent outlet, 29—discharge port, 30—waste outlet, 31—water injection pipe, 32—control valve, 33—agent filling pipe, 34—agent outlet valve, 35—filter, 36—diaphragm metering pump, 37—pressure sensor, 38—damper, 39—check valve, 40—electromagnetic control filling valve, 41—pressure gauge, 42—safety pressure relief reflux pipe, 43—forced pressure relief reflux pipe, 44—safety pressure relief valve, 45—control ball valve, 46—forced pressure relief valve, 47—waste main pipe, 48—waste main valve, 49—defoaming agent waste valve, 50—desulfurization agent waste valve, 51—neutralizer waste valve, 52—main road, 53—branch road, 54—skid, 55—main road lifting beam, 56—line reel, 57—tool rack, 58—skid lifting ring. DETAILED DESCRIPTION

[0017] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0018] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0019] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0020] Example 1: The main workflow diagram of this embodiment is as follows: Figure 1 As shown, it includes a mixing agitator for treating wellhead flowback liquid and three chemical storage tanks for storing desulfurizer, neutralizer and defoaming agent respectively, and the mixing agitator is connected to the chemical storage tanks storing corresponding chemicals through independent chemical filling pipes; each of the chemical storage tanks is connected in parallel between the feed main pipe and the discharge main pipe through the feed pipe arranged at the upper part and the discharge pipe arranged at the lower part; the feed pipe of each chemical storage tank is provided with a feed valve, and the discharge pipe is provided with a discharge valve, and gear pumps are installed at the inlet of the feed main pipe and the outlet of the discharge main pipe; the mixing agitator is connected to the flowback liquid input pipe and the tail water discharge pipe respectively; the tail water discharge pipe is also equipped with a pH detection sensor and a sulfide detection sensor.

[0021] The overall structure diagram of the system is as follows: Figure 2 As shown, all structures and pipelines are centrally installed in a skid similar to a container.

[0022] The operation process includes the following steps: (1) By controlling the feed valve on the feed pipe of each of the pharmaceutical storage tanks, the corresponding pharmaceutical is fed into the corresponding pharmaceutical storage tank through the gear pump on the feed main pipe. When the level meter signal senses that the volume has reached the program setting, the feed is stopped; (2) After the corresponding reagents are added to the corresponding reagent storage tank through the feed pipe, the desulfurizer, defoamer and neutralizer are injected into the mixing agitator through the independently arranged reagent filling pipe at the bottom, and the mixing agitator inputs the return liquid that needs to be desulfurized through the return liquid input pipe. The mixing agitator mixes the return liquid that needs to be desulfurized and the injected reagents, and performs desulfurization, defoaming and neutralization treatment on the return liquid; (3) The mixer discharges the treated flowback liquid through the tailwater discharge pipe. A sulfide detection sensor and a pH value detection sensor are installed on the tailwater discharge pipe. The sulfide detection sensor and the pH value detection sensor collect the data of the tailwater in the tailwater discharge pipe and feedback the situation of the tailwater. The filling situation of the reagent in the mixer can be adjusted according to the situation of the tailwater; (4) When all operations are completed and the equipment needs to be transferred, the unloading valve on each unloading pipe of the reagent storage tank can be controlled, and the remaining reagents in the corresponding reagent storage can be output from the unloading main pipe through the gear pump on the unloading main pipe for separate storage; (5) The residual liquid and sediment in the reagent storage tank are discharged through the waste discharge mechanism and collected and treated separately.

[0023] Example 2: Based on the above embodiment, this embodiment further defines the mechanism for feeding each drug storage tank, such as Figure 3 As shown, it includes various feed pipes connected in parallel to the feed main pipe 6 and connected to the corresponding reagent storage tanks. These feed pipes include a defoamer feed pipe, a desulfurizer feed pipe, and a neutralizer feed pipe. The outlet of the defoamer feed pipe is provided with a defoamer feed valve 1, the outlet of the desulfurizer feed pipe is provided with a desulfurization tank feed valve 2, and the outlet of the neutralizer feed pipe is provided with a neutralizer feed valve 3. The inlet end of the feed main pipe 6 is provided with an electromagnetically controlled feed valve 5 and a main feed valve 7. A feed gear pump 4 is provided on the pipeline between the main feed valve 7 and the electromagnetically controlled feed valve 5.

[0024] In the initial state of feeding the agent storage tank, the defoaming agent feed valve 1, the desulfurization tank feed valve 2, the neutralizer feed valve 3, the electromagnetic control feed valve 5, and the main feed valve 7 are all in the closed state.

[0025] When it is necessary to feed defoaming agent into the dosage storage tank, open the defoaming tank feed valve 1, the electromagnetically controlled feed valve 5, and the main feed valve 7, and the feed gear pump 4 starts to operate. After the feeding is completed, the defoaming tank feed valve 1, the electromagnetically controlled feed valve 5, and the main feed valve 7 are closed, and the feed gear pump 4 stops.

[0026] When it is necessary to feed desulfurizer into the reagent storage tank, open the desulfurizer tank feed valve 2, the electromagnetically controlled feed valve 5, and the main feed valve 7, and the feed gear pump 4 starts to operate. After the feeding is completed, the desulfurizer tank feed valve 2, the electromagnetically controlled feed valve 5, and the main feed valve 7 are closed, and the feed gear pump 4 stops working.

[0027] When the neutralizer needs to be fed into the dosage storage tank, the neutralization tank feed valve 3, the electromagnetically controlled feed valve 5, and the feed main valve 7 are opened, and the feed gear pump 4 starts to operate. After the feeding is completed, the neutralization tank feed valve 3, the electromagnetically controlled feed valve 5, and the feed main valve 7 are closed, and the feed gear pump 4 stops operating. The rest of this embodiment is the same as the above embodiment and will not be repeated here.

[0028] Example 3: When the drug storage tank needs to be transferred or cleaned, the unloading mechanism is required to extract the drugs in the drug storage tank. Therefore, based on the above embodiment, this embodiment further defines the mechanism for unloading the drug storage tanks, such as Figure 4As shown, it includes various discharge pipes connected in parallel to the discharge main pipe 13 and connected to the corresponding reagent storage tanks. These discharge pipes include a defoamer discharge pipe, a desulfurizer discharge pipe, and a neutralizer discharge pipe. The outlet of the defoamer discharge pipe is provided with a defoamer discharge valve 8, the outlet of the desulfurizer discharge pipe is provided with a desulfurization tank discharge valve 9, and the outlet of the neutralizer discharge pipe is provided with a neutralizer discharge valve 10. The inlet end of the discharge main pipe 13 is provided with an electromagnetically controlled discharge valve 12 and a discharge main valve 14. A discharge gear pump 11 is provided on the pipeline between the discharge main valve 14 and the electromagnetically controlled discharge valve 12.

[0029] In the initial state of unloading the drug storage tank, the defoaming agent unloading valve 8, the desulfurization tank unloading valve 9, the neutralizer unloading valve 10, the electromagnetic control unloading valve 12, the unloading main valve 14, the defoaming agent feed valve 1, the desulfurization tank feed valve 2, and the neutralizer feed valve 3 are all in the closed state.

[0030] When it is necessary to unload the defoaming agent from the dosage storage tank, open the defoaming tank unloading valve 8, the electromagnetically controlled unloading valve 12, and the unloading main valve 14, and the unloading gear pump 11 starts to operate. After the unloading is completed, the defoaming tank unloading valve 8, the electromagnetically controlled unloading valve 12, and the unloading main valve 14 are closed, and the unloading gear pump 11 stops.

[0031] When it is necessary to unload the desulfurizer from the reagent storage tank, open the desulfurizer tank unloading valve 9, the electromagnetically controlled unloading valve 12, and the unloading main valve 14, and the unloading gear pump 11 starts to operate. After the unloading is completed, the desulfurizer tank unloading valve 9, the electromagnetically controlled unloading valve 12, and the unloading main valve 14 are closed, and the unloading gear pump 11 stops working.

[0032] When the neutralizer needs to be discharged from the pharmaceutical storage tank, the neutralization tank discharge valve 10, the electromagnetically controlled discharge valve 12, and the discharge main valve 14 are opened, and the discharge gear pump 11 starts to operate. After the discharge is completed, the neutralization tank discharge valve 10, the electromagnetically controlled discharge valve 12, and the discharge main valve 14 are closed, and the discharge gear pump 11 stops. The rest of this embodiment is the same as the above embodiment and will not be repeated here.

[0033] Example 4: On the basis of the above embodiment, this embodiment further defines the relationship between the feed main pipe 6 and the discharge main pipe 13, such as Figure 5As shown, a first spare pipe 15 and a second spare pipe 16 are arranged in parallel between the feed main pipe 6 and the discharge main pipe 13. The first spare pipe 15 connects the feed main pipe 6 between the feed gear pump 4 and the electromagnetically controlled feed valve 5, and the discharge main pipe 13 between the discharge gear pump 11 and the electromagnetically controlled discharge valve 12. The second spare pipe 16 connects the feed main pipe 6 between the feed main valve 7 and the feed gear pump 4, and the discharge main pipe 13 between the discharge main valve 14 and the discharge gear pump 11. A first spare valve 17 is provided on the first spare pipe 15, and a second spare valve 18 is provided on the second spare pipe 15.

[0034] The arrangement of the first backup pipeline 15 and the second backup pipeline 16 enables a partial backup between the feeding mechanism and the unloading mechanism, and the functions of the two can be switched. The specific operation process is as follows: In the initial state, the defoaming agent feed valve 1, the desulfurization tank feed valve 2, the neutralizer feed valve 3, the electromagnetically controlled feed valve 5, the main feed valve 7, the second spare valve 18, the electromagnetically controlled discharge valve 12, the main discharge valve 14, the first spare valve 17, the defoaming agent discharge valve 8, the desulfurization tank discharge valve 9, and the neutralizer discharge valve 10 are all in the closed state, and the feed gear pump 4 and the discharge gear pump 11 are not operating.

[0035] When the feed gear pump 4 fails, the discharge gear pump 11 is activated to complete the feeding process. At this time, the electromagnetically controlled feed valve 5, the first backup valve 17, the second backup valve 18, the main feed valve 7, and the corresponding feed valve (one of the defoamer feed valve 1, the desulfurization tank feed valve 2, or the neutralizer feed valve 3, depending on the specific feed agent) are opened, and the discharge gear pump 11 starts to operate. The corresponding feed agent then flows from the electromagnetically controlled feed valve 5 → the first backup pipe 15 → the first backup valve 17 → the discharge gear pump 11 → the second backup valve 16 → the second backup valve 18 → the main feed valve 7 → the main feed pipe 6 → the corresponding feed pipe → the corresponding agent storage tank (one of the defoamer tank, the desulfurization tank, or the neutralizer tank, depending on the specific feed agent). After the feeding of the corresponding agent storage tank is completed, all the electromagnetically controlled feed valves 5, the first backup valve 17, the second backup valve 18, the main feed valve 7, and the corresponding feed valves return to the closed state, and the discharge gear pump 11 stops operating.

[0036] When the unloading gear pump 11 fails, the feeding gear pump 4 is activated to complete the unloading process. At this time, the electromagnetically controlled discharge valve 12, the first backup valve 17, the second backup valve 18, the main discharge valve 14 and the corresponding discharge valves (one of the defoaming agent discharge valve 8, the desulfurization tank discharge valve 9, and the neutralizer discharge valve 10, selected according to the specific feed agent) are opened, and the feed gear pump 4 is in operation. The corresponding feed agent is fed from the corresponding agent storage tank (one of the defoaming agent tank, the desulfurization tank, and the neutralizer tank, selected according to the specific discharge agent) → the corresponding discharge pipe → the main discharge pipe 13 → the main discharge valve 14 → the first backup valve 17 → the first backup pipe 15 → the feed gear pump 4 → the second backup valve 18 → the first backup pipe 16 → the discharge valve 12. After completing the discharge of the corresponding agent storage tank, all the electromagnetically controlled discharge valves 12, the first backup valve 17, the second backup valve 18, the main discharge valve 14 and the corresponding discharge valves return to the closed state, and the feed gear pump 4 stops operating.

[0037] All pipelines are made of stainless steel and are low-pressure pipelines. Each pipeline joint is connected by flanges or manhole plugs. Operators can disassemble the pipelines and open the manhole plugs to clear the pipelines, perform maintenance, etc. The rest of this embodiment is the same as the above embodiment and will not be repeated here.

[0038] Example 5: Based on the above embodiment, this embodiment further defines the specific structure of the medicine storage tank, such as Figure 6 As shown, the tank body 19 includes a top inspection manhole 20, a feed port 21, an explosion-proof and fire-resistant breathing valve 22, a safety pressure relief reflux port 23, and a forced pressure relief reflux port 24. A magnetic flap level gauge 26 and a side inspection manhole 27 are also provided on the side of the tank body. A reagent outlet 28, a discharge port 29, and a waste outlet 30 are provided at the bottom of the tank body 1. Two manual ball valves 25 are connected in series between the ends of the magnetic flap level gauge 26 and the tank body 1.

[0039] The tank body 1 adopts a cylindrical design, which increases space utilization under the same volume. Moreover, the cylindrical design reduces the wall thickness and is lighter under the same load-bearing capacity.

[0040] The top inspection manhole 20 adopts a circular design and is tightened by six manually twisted hand wheels. The manhole cover can be opened manually by manually loosening the hand wheels. The side inspection manhole 27 adopts a circular design and uses a normal pressure standard manhole design.

[0041] The discharge port 29, waste outlet 30, agent outlet 28, forced pressure relief reflux port 24, safety pressure relief reflux port 23, and feed port 21 provided on the tank body 1 are connected to corresponding pipelines.

[0042] The liquid level in the tank 1 is fed back in real time by a magnetic flap level gauge 26, which can be read visually and is equipped with a data acquisition interface. Two manual ball valves 25 are connected in series between the magnetic flap level gauge 26 and the tank 1. When the magnetic flap level gauge 26 is operating, the two manual ball valves 25 are open. If the magnetic flap level gauge 26 malfunctions, the two manual ball valves 25 are closed for repair or replacement.

[0043] An explosion-proof and fire-retardant breathing valve 22 is installed on the top of the tank body 1 to ensure that the pressure in the tank body 1 is constant when adding and discharging the medicine.

[0044] The structures of the neutralizer tank, desulfurizer tank and defoamer tank are basically the same. Among them, the neutralizer tank is added with a water injection pipe 31 for introducing an external water source, and a control valve 32 is provided on the water injection pipe 31. Figure 7 When water injection and dilution are required, the control valve 32 is opened to complete the water injection and dilution requirements in the neutralizer tank. The other parts of this embodiment are the same as those in the above embodiment and will not be described here.

[0045] Example 6: On the basis of the above embodiment, this embodiment further defines a filling mechanism for filling the medicine in the medicine storage tank into the mixing agitator. In order to better demonstrate the filling mechanism, the structure of the medicine filling mechanism in one of the medicine storage tanks is described. Figure 8 As shown, it includes a medicine filling pipe 33 connected to the medicine outlet 28 of the medicine storage tank, and the medicine filling pipe 33 is provided with a medicine outlet valve 34, a filter 35, a hydraulic diaphragm metering pump 36, a pressure sensor 37, a damper 38, a one-way valve 39, and an electromagnetically controlled filling valve 40 in sequence according to the flow direction of the medicine.

[0046] The process of filling the chemical storage tank is as follows: In the initial state, the medicine outlet valve 34, the diaphragm metering pump 36, and the electromagnetically controlled filling valve 40 are all in the closed state.

[0047] After the operator starts the equipment, the diaphragm metering pump 36 is started, and the agent outlet valve 34 and the electromagnetic control filling valve 40 are opened.

[0048] According to the pressure signal fed back by the pressure sensor 37 and in combination with the dosage setting value of the automatic control system, the opening of the diaphragm metering pump 36 is adjusted to achieve control of the dosage per unit time.

[0049] The reagent filling pipe is equipped with three pressure detection points. A pressure gauge 41 is arranged on the main line to facilitate the operator to read the pressure value intuitively, and a pressure sensor 37 is arranged to remotely monitor and record the pressure value in real time.

[0050] There is a constant pressure air bag inside the damper 38, which is wrapped by an external metal shell and is used to balance the pressure fluctuations at the outlet end of the diaphragm metering pump 36 to ensure that the pressure of the drug filling pipeline is relatively stable.

[0051] The filling mechanism is also connected to a safety pressure relief return pipe 42 and a forced pressure relief return pipe 43 . The safety pressure relief return pipe 42 is installed with a safety pressure relief valve 44 and a control ball valve 45 . The forced pressure relief return pipe 43 is installed with a forced pressure relief valve 46 .

[0052] The safety pressure relief process is as follows: In the initial state, the safety pressure relief valve 44 and the control ball valve 45 are closed. When the agent filling begins, according to the pressure gauge reading, when the pressure in the agent filling pipe 33 exceeds the set pressure, the safety pressure relief valve 44 and the control ball valve 45 open, and the agent flows back into the tank body 19 of the agent storage tank, achieving the pressure relief and internal circulation functions.

[0053] The forced pressure relief process is as follows: in the initial state, the forced pressure relief valve is closed. When the pressure in the filling pipe 33 exceeds the set pressure and the safety pressure relief valve 44 does not open normally, the forced pressure relief valve 46 is opened based on the pressure value fed back by the pressure sensor 37 to achieve the purpose of pressure relief.

[0054] The filling mechanism also has a circulation stirring function. The specific process is: when the medicine in the tank body 19 of the medicine storage tank needs to be stirred and mixed, the operator starts the corresponding medicine storage tank circulation stirring function. After starting, the forced pressure relief valve 46 is opened, the electromagnetic control filling valve 40 is closed, the medicine outlet valve 34 is opened, and the diaphragm metering pump 36 is started to run, thereby realizing the medicine circulation stirring function in the tank body 19 of the medicine storage tank.

[0055] Among them, the reagent filling pipe 33 connected to the neutralizer storage tank, the safety pressure relief reflux pipe 42, and the forced pressure relief reflux pipe 43 are all pipes with larger diameters, while the reagent filling pipe 33 connected to the desulfurizer storage tank and the defoaming agent uses a pipe with larger diameters, and its safety pressure relief reflux pipe 42 and the forced pressure relief reflux pipe 43 are both pipes with smaller diameters.

[0056] In order to facilitate inspection and troubleshooting, maintenance purge ports are also provided at the reagent outlet valve 34, the filter 35, and the forced pressure relief valve 46.

[0057] The overall structure of the filling mechanism, such as Figure 9 The rest of this embodiment is the same as the above embodiment and will not be described again here.

[0058] Example 7: Based on the above embodiment, this embodiment further defines the specific structure of the waste discharge mechanism, such as Figure 10As shown, it includes a waste discharge pipe connected to the waste discharge port 30 at the lower part of the tank body 19, each waste discharge pipe is connected to the waste discharge main pipe 47, and a waste discharge main valve 48 is provided at the outlet end of the waste discharge main pipe 47. According to the agent storage tank connected to the waste discharge pipe, a defoaming agent waste discharge valve 49, a desulfurizing agent waste discharge valve 50, and a neutralizing agent waste discharge valve 51 are respectively provided thereon.

[0059] The specific operation process of waste discharge is as follows: in the initial state, the defoaming agent waste discharge valve 49, the desulfurizing agent waste discharge valve 50, the neutralizing agent waste discharge valve 51 and the waste discharge main valve 48 are in the closed state.

[0060] Taking the neutralizer storage tank as an example, when the neutralizer tank waste liquid needs to be discharged, the main discharge valve 48 and the neutralizer discharge valve 51 are opened. After the discharge process is completed, the main discharge valve 48 and the neutralizer discharge valve 51 are closed. Similarly, when the desulfurizer tank and the defoamer tank need to be discharged, the process flow is the same. The defoamer discharge valve 49, the desulfurizer discharge valve 50, the neutralizer discharge valve 51, and the main discharge valve 48 can be controlled by PLC electric control valves or manual ball valves, and the operator can complete the discharge manually.

[0061] The waste pipes connecting the main waste pipe 47 to the various reagent storage tanks are all low-pressure pipes. Each pipe joint uses a flange and a customized maintenance connector and manhole plug. Operators can disassemble the pipes and open the manhole plugs to perform operations such as clearing and maintenance on the pipes. The rest of this embodiment is the same as the above embodiment and will not be repeated here.

[0062] Example 8: Based on the above embodiment, this embodiment further adds a control system, which receives tail water information fed back by pH detection sensor and sulfide detection sensor, the liquid level information in the corresponding drug storage tank fed back by each liquid level meter, and the drug flow and hydraulic information in the corresponding drug filling pipe fed back by each diaphragm metering pump and pressure sensor; and controls the feed valve, discharge valve, main feed valve, main discharge valve, and electric valve of each pipeline through the received information, so that the tail water finally flowing out of the mixing agitator meets the purification standards. The line bridge structure of the control system is as follows: Figure 11 As shown, the cross-section of the main line 52 of the line bridge is larger than the cross-section of the branch line 53. A partition is used in the middle of the bridge to separate the strong and weak current lines. The line bridge is fixed by bolts, and the branch bridge is designed to be supported by a vertical bracket. The rest of this embodiment is the same as the above embodiment and will not be repeated here.

[0063] Example 9: Based on the above embodiment, this embodiment further defines the structure of the pry body 54, such as Figure 2 , Figure 12As shown, all the drug storage tanks and the corresponding pipelines and valves are installed in the skid body 54. A plurality of main road hanging beams 55 are arranged in the skid body 54 for hanging the line bridge and increasing the load-bearing capacity of the main body top. A wire reel 56 and a tool rack 57 are provided on one side of the skid body. The power cord winding rack adopts a hoisting structure design. The wire reel 56 has a non-return function. The wire is led out of the skid body hole with a wire roller for sliding wire protection. The skid body 51 is designed with five compartments as a tool rack 57.

[0064] The main beams surrounding the base of skid 51 are constructed of channel steel or square steel. The top is made of corrugated sheet metal, welded to the top structure and waterproofed. A water channel is provided at the top with a sloped top, and the top drain is securely connected to the liquid storage tank's sewage pipeline. The bottom layer of skid 51 is welded to the bottom structure with a sloped bottom layer and a drain outlet at the lowest end to ensure that all water on the bottom plate can be discharged through this outlet.

[0065] The four corners of the top and bottom of the skid body 51 are also provided with skid body lifting rings 58 to meet the needs of crane hook suspension.

[0066] The skid 51 has three doors on the front to facilitate the debugging and maintenance of the metering pumps, the medicine storage tank and the control system. The other parts of this embodiment are the same as those of the above embodiment and will not be described in detail here.

[0067] Example 10: On the basis of the above embodiment, this embodiment further defines the mixing agitator, which is mainly composed of a mixer skid and a pH value detection skid, such as Figure 13 , Figure 14 As shown, the mixer skid consists of two mixers connected in series and then connected in parallel via a bypass line consisting of tees, elbows, and valves. When the flowback flow exceeds the maximum flow of the mixer, the bypass line is opened to ensure the safety of the mixer.

[0068] The mixer uses the flow rate of the return fluid to drive the multiple propeller blades inside the mixer to rotate. The blades stir the return fluid, causing it to react with the reagent entering from the branch line. The faster the flow rate, the more intense the stirring, ensuring that the flow rate and reaction rate match. The mixed liquid is tested for sulfur dioxide and hydrogen sulfide in real time by a sulfide detection device. The collected data is uploaded to the automatic control system. Based on the collected feedback data, the automatic control system adjusts the ratio of the reagent injection output by the metering pump in real time to achieve precise dosage.

[0069] The pH test skid consists of a mixer and a pH calibration device connected in series. The mixed liquid from the mixer skid reacts with the neutralizer in a third mixer after stirring before entering the pH calibration device. The pH meter is housed in a protective shield covered with small holes to prevent damage to the pH meter glass cover by the fluid. The pH calibration device is designed with a low inlet and a high outlet to ensure sufficient contact between the mixed liquid and the pH meter. The collected data is uploaded to the automatic control system, which, based on the collected feedback, adjusts the metering pump output in real time to adjust the neutralizing agent dosage ratio to achieve precise dosage.

[0070] It is understood that the desulfurization system structure according to one embodiment of the present invention, such as the working principles and working processes of components such as the control system and various valves, are all prior art and are well known to those skilled in the art, and will not be described in detail here.

[0071] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. A wellhead flowback fluid desulfurization system, characterized in that: It includes a mixing agitator for treating wellhead flowback liquid and three chemical storage tanks for storing desulfurizer, neutralizer and defoaming agent respectively. The mixing agitator is connected to the chemical storage tanks storing corresponding chemicals through independent chemical filling pipes; each of the chemical storage tanks is connected in parallel between the feed main pipe and the discharge main pipe through a feed pipe arranged at the upper part and a discharge pipe arranged at the lower part; the feed pipe of each chemical storage tank is provided with a feed valve, and the discharge pipe is provided with a discharge valve, and gear pumps are installed on the inlet of the feed main pipe and the outlet of the discharge main pipe; the mixing agitator is connected to the flowback liquid input pipe and the tail water discharge pipe respectively; the tail water discharge pipe is also equipped with a pH detection sensor and a sulfide detection sensor.

2. A wellhead flowback fluid desulfurization system according to claim 1, characterized in that: Two spare pipelines are also arranged in parallel between the feed main pipe and the discharge main pipe, and each spare pipeline is provided with a spare valve.

3. A wellhead flowback fluid desulfurization system according to claim 5, characterized in that: Each of the pharmaceutical storage tanks is also provided with a waste discharge pipe and a liquid level gauge, each of the waste discharge pipes is connected to a waste discharge main pipe, each of the waste discharge pipes is provided with a waste discharge valve, and the waste discharge main pipe is provided with a waste discharge main valve.

4. A wellhead flowback fluid desulfurization system according to claim 3, characterized in that: The pressure relief pipe is also provided with a safety pressure relief reflux pipe. The safety pressure relief reflux pipes of different pharmaceutical storage tanks are connected with the corresponding pharmaceutical filling pipes of the pharmaceutical storage tanks. Each of the safety pressure relief reflux pipes is also provided with a safety valve.

5. A wellhead flowback fluid desulfurization system according to claim 4, characterized in that: Each of the medicine storage tanks is further provided with a forced pressure relief reflux pipe connected to the corresponding safety pressure relief reflux pipe, and each of the forced pressure relief reflux pipes is further provided with a forced pressure relief valve.

6. A wellhead flowback fluid desulfurization system according to claim 5, characterized in that: Each of the medicine filling pipes is provided with a diaphragm metering pump, a pressure sensor, and a one-way valve.

7. A wellhead flowback fluid desulfurization system according to claim 6, characterized in that: The return liquid input pipe, tail water discharge pipe, each reagent filling pipe, feed main pipe, and discharge main pipe are all provided with independent electric valves. The feed main pipe is also provided with a feed main valve, and the discharge main pipe is also provided with a discharge main valve.

8. A wellhead flowback fluid desulfurization system according to claim 7, characterized in that: It also includes a control system, which receives tail water information fed back by the pH detection sensor and the sulfide detection sensor, the agent liquid level information in the corresponding agent storage tank fed back by each liquid level meter, and the agent flow and hydraulic information in the corresponding agent filling pipe fed back by each diaphragm metering pump and pressure sensor; and controls the feed valve, discharge valve, main feed valve, main discharge valve, and electric valve of each pipeline through the received information, so that the tail water finally flowing out of the mixing agitator meets the purification standards.

9. A wellhead flowback fluid desulfurization system according to claim 8, characterized in that: It also includes a skid that houses all pharmaceutical storage tanks and corresponding pipes and valves and seals them.

10. A wellhead flowback fluid desulfurization system according to claim 9, characterized in that: The skid is also provided with a line bridge for controlling system wiring.

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