Fracturing flow-back fluid recycling system
By designing a fracturing reflux fluid recovery and treatment system, using measurement and dosing technology, the problems of waste and safety hazards of strong acid agents in the existing technology have been solved, and efficient and safe treatment of fracturing reflux fluid has been achieved.
Patent Information
- Application Number
- CN202421432152.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-21
- Publication Date
- 2025-03-28
- Estimated Expiration
- 2034-06-21
AI Technical Summary
In the prior art, the strong acid agent used to treat fracturing reflux fluid is wasteful and poses huge safety hazards.
A fracturing retrieval fluid recovery and treatment system is designed, including a liquid pump, an electrocoagulation device, a filtration system and a dosing device. By measuring liquid parameters and selecting and adding agents based on the measurement results, efficient treatment and adjustment of the fracturing retrieval fluid can be achieved.
Through the combination of measurement and dosing, waste and safety hazards caused by the single-use use of a large number of strong acid agents are avoided, and treatment efficiency and safety are improved.
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Figure CN222684482U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of oilfield sewage treatment, in particular to a fracturing return fluid recovery and treatment system. Background Art
[0002] Fracturing is one of the main measures to increase the production of oil and gas wells in oil field work. Its main principle is to inject fracturing fluid into the bottom layer under high pressure to expand the cracks in the formation and create new cracks, and then fill in proppants to increase the permeability of the formation. The main function of fracturing fluid is to transmit pressure, form cracks and carry proppants into the cracks. Therefore, fracturing fluid must have a high viscosity. The residual fracturing fluid discharged from the oil and gas well after fracturing construction is called fracturing flowback fluid. The main components include fracturing original gel fluid and broken gel flowback fluid. It contains guar gum, formaldehyde, petroleum and other various additives. It has complex pollutant composition, high sand content, high viscosity, and its internal composition varies greatly in different systems and types of fracturing flowback fluids. They are all multiphase mixtures, which are difficult to handle. Direct discharge is likely to cause harmful effects on the surrounding environment. In the prior art, the treatment of fracturing flowback fluid is very simple. Usually, a large amount of strong acid reagents are added to degrade the fracturing flowback fluid to reduce the viscosity of the fracturing flowback fluid. However, this method wastes a large amount of drugs during the treatment process, and the use of a large amount of strong acid reagents poses a huge safety hazard in the production process. Therefore, in view of the above shortcomings, a fracturing flowback fluid recovery and treatment system is proposed. Summary of the invention
[0003] The utility model aims to provide a fracturing flowback fluid recovery and processing system to overcome the defects of the prior art in that a large amount of strong acid agents are wasted when processing fracturing flowback fluid and a large amount of strong acid agents are used, which may cause huge safety hazards in production.
[0004] In order to achieve the above-mentioned purpose, the utility model provides a fracturing flowback fluid recovery and processing system, comprising:
[0005] A skid-mounted base, on which a liquid pump, an electrocoagulation device and a filtration system are provided, wherein the filtration system comprises a quartz sand filter and a backwash filtration device; the input end of the liquid pump is connected to the liquid outlet on site, and the output end is connected to the inlet of the electrocoagulation device; the liquid outlet of the electrocoagulation device is connected to the inlet of the quartz sand filter, and the outlet of the quartz sand filter is connected to the inlet of the backwash filtration device; a primary measuring instrument is provided between the electrocoagulation reaction device and the liquid pump, and a primary dosing device is provided at the outlet of the primary measuring instrument; a secondary dosing device is provided at the outlet of the filtration device, and a secondary measuring instrument is provided after the secondary dosing device.
[0006] Preferably, a plurality of lifting ears are evenly arranged on the skid-mounted base.
[0007] Preferably, a screw stacking machine is provided behind the electrocoagulation device, a sewage discharge hole is provided at the bottom of the electrocoagulation device, and the inlet of the screw stacking machine is connected to the sewage discharge hole.
[0008] Preferably, a fine filtration system is provided after the filtration system, the secondary dosing device is located after the fine filtration system, and a secondary measuring instrument is provided after the secondary dosing device.
[0009] Preferably, the fine filtration system includes an activated carbon filtration device, a primary filter and a secondary filter; the outlet end of the backwash filtration device is connected to the activated carbon filtration device, and the activated carbon filtration device is connected to the primary filter and the secondary filter in sequence, and the secondary dosing device is located behind the output end of the secondary filter.
[0010] Preferably, the primary filter and the secondary filter are both bag filters, and the filtering accuracy of the secondary filter is higher than that of the primary filter.
[0011] Preferably, the primary measuring instrument and the secondary measuring instrument are both turbidity measuring instruments.
[0012] The utility model provides a fracturing flowback fluid recovery and processing system with the following beneficial effects:
[0013] The fracturing return fluid recovery and processing system provided by the utility model can first measure the parameters of the fracturing return fluid and then select and add the corresponding reagents to process and adjust the fracturing return fluid by providing a primary measuring instrument and a primary dosing device; and perform secondary measurement on the treated return fluid by providing a secondary dosing device and a secondary measuring instrument after the filtration system and dosing and adjusting again according to the measurement results. The type and amount of the reagent used can be changed according to the measurement results, thereby avoiding the waste of reagents caused by the one-time use of a large amount of strong acid reagents, and avoiding the safety hazards caused by the use of a large amount of strong acid reagents. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 This is a schematic diagram of the structure of the fracturing flowback fluid recovery and treatment system.
[0015] Legend:
[0016] 1. Liquid pump; 2. Primary dosing device; 3. Primary measuring instrument; 4. Electrocoagulation flocculation reaction device; 5. Quartz sand filter; 6. Backwashing filter device; 7. Secondary dosing device; 8. Secondary measuring instrument; 9. Screw stacking machine; 10. Activated carbon filtration device; 11. Primary filter; 12. Secondary filter. DETAILED DESCRIPTION
[0017] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0018] like Figure 1 As shown, the utility model provides a fracturing flowback fluid recovery and processing system, comprising:
[0019] The skid-mounted base serves as the framework of the system and is used to install other devices in the system. The working position of the system can be changed by moving the skid-mounted base during the actual working process. The skid-mounted base is provided with a liquid pump 1, an electrocoagulation device 4 and a filtration system. The liquid pump 1 is used to collect the fracturing return fluid at the work site. Generally, the input end of the liquid pump 1 is inserted into the target oil well or connected to the fracturing return fluid interface at the site. After starting the liquid pump 1, the fracturing return fluid is pumped into the system for treatment under the action of the liquid pump 1. Generally, the skid-mounted base is connected by "I"-shaped steel.
[0020] The skid-mounted base is evenly provided with a plurality of lifting ears, which are used to cooperate with the lifting equipment at the work site to lift and move the system. During the work process, after the lifting ears are connected to the lifting equipment through ropes such as lifting belts or lifting ropes, the skid-mounted base can change its position following the movement of the lifting equipment, thereby enabling the installation of the system at the work site.
[0021] It should be noted that a primary measuring instrument 3 is provided between the electrocoagulation reaction device 4 and the liquid pump 1, a primary dosing device 2 is provided in front of the primary measuring instrument 3, a secondary dosing device 7 is provided at the outlet of the filtering device, and a secondary measuring instrument 8 is provided behind the secondary dosing device 7. The primary measuring instrument 3 and the secondary measuring instrument 8 can measure the parameters of the circulating liquid, and the primary dosing device 2 and the secondary dosing device 7 can add treatment agents to the circulating liquid. In actual work, after judging the internal composition and properties of the circulating liquid according to the readings of the primary measuring instrument 3 and the secondary measuring instrument 8, different types of treatment agents are added to the circulating liquid through the primary dosing device 2 and the secondary dosing device 7 to change the properties of the circulating liquid. The dosage of the added treatment agent can be adjusted through the primary dosing device 2 and the secondary dosing device 7, thereby avoiding the waste of drugs caused during the dosing process and eliminating the safety hazards of using a large amount of strong acid agents.
[0022] In addition, the primary measuring instrument 3 and the secondary measuring instrument 8 are generally turbidity testers, which can measure parameters such as turbidity, suspended matter and sludge interface in the liquid. The treatment reagents include disinfectants, catalysts and flocculants. When the bacterial components in the liquid exceed the standard, adding disinfectants can sterilize the liquid; when the water quality is seriously polluted or under harsh conditions such as low temperature in winter, it will affect the reaction efficiency of the flocculation process. At this time, adding catalysts to the liquid can speed up the reaction efficiency in the flocculation process and improve work efficiency; the flocculant can add metal cations Fe, Al, etc. to the liquid to ensure the stability of the flocculation process and improve the stability of the device. The disinfectant, catalyst and flocculant can all be directly obtained by purchase.
[0023] In the utility model, the output end of the liquid pump 1 is connected to the electrocoagulation device 4, and the liquid pump 1 sucks the fracturing return fluid into the electrocoagulation device 4. The electrocoagulation device 4 passes a high-voltage current into the fracturing return fluid. Under the action of the high-voltage current, an oxidation-reduction reaction occurs in the fracturing return fluid. At this time, the soluble anodes such as iron, aluminum, etc. inside the fracturing return fluid lose electrons after being passed through high-voltage pulse direct current, forming metal cations Fe and Al, which combine with OH in the solution to form highly active flocculant groups, which have extremely strong adsorption capacity and better flocculation effect than ordinary flocculants, and can adsorb and co-precipitate pollutants in the wastewater to remove them.
[0024] Among them, in actual work, it is usually necessary to add a solution rich in metal cations Fe and Al as a flocculant to the electrocoagulation device 4, and to supplement metal cations Fe, Al, etc. into the fracturing return fluid, so that the fracturing return fluid can stably produce highly active flocculants when powered on, adsorb and co-precipitate pollutants in the wastewater to remove them, improve the system's treatment effect on the fracturing return fluid, and improve work efficiency. At the same time, in the electrocoagulation device 4, after power is turned on, the water in the fracturing return fluid undergoes an electrolysis reaction under the action of high voltage electricity, and the water is hydrolyzed to generate hydrogen and oxygen, forming many tiny bubbles in the fracturing return fluid, which act as carriers to adhere to suspended solids in the water and float up, capturing impurity particles in the fracturing return fluid.
[0025] It should be noted that a screw stacking machine 9 is provided behind the electroflocculation device 4, a drainage hole is provided at the bottom of the electroflocculation device 4, and the inlet of the screw stacking machine 9 is connected to the drainage hole. After the electroflocculation device 4 works, the solid-liquid mixture precipitated to the bottom is discharged through the drainage hole. After the solid-liquid mixture discharged from the electroflocculation device 4 enters the screw stacking machine 9, the screw stacking machine 9 is powered on to compress and dehydrate the solid-liquid mixture, thereby achieving solid-liquid separation of the waste generated by flocculation, and facilitating the recovery and cleaning of the waste generated after flocculation.
[0026] like Figure 1As shown, the filtration system includes a quartz sand filter 5 and a backwash filter device 6, wherein the inlet of the quartz sand filter 5 is connected to the electrocoagulation device 4, and the outlet is connected to the backwash filter device 6. The quartz sand filter 5 uses quartz sand as the filter medium. After the liquid enters the quartz sand filter device 4, it will flow through the internal quartz sand. The suspended matter and colloid in the liquid are separated from the liquid under the adsorption of the quartz sand and attached to the quartz sand filter 5, thereby further filtering the fracturing return fluid. The backwash filter device 6 is provided with a coarse and fine two-layer filter screen inside. After the liquid enters the backwash filter device 6, it first passes through the coarse filter screen to filter the large particles of impurities, and then passes through the fine filter screen to filter the fine particles of impurities in the liquid. After the backwash filter device 6 works for a long time, impurities will adhere to the filter screen to form an impurity layer, causing the filter screen to be blocked and affecting the filtering effect. The backwash filter device 6 has a backwash function. After the filter screen is blocked, the internal filter screen can be backwashed and cleaned without disassembly, thereby maintaining the filtering effect of the backwash filter device 6. Generally, the outlet of the electrocoagulation device 4 is connected to the inlet of the quartz sand filter 5, and the fracturing flowback fluid treated by the electrocoagulation device 4 is input into the filtering system for filtration.
[0027] Among them, a fine filtration system is provided after the filtration system, which is used to filter the liquid treated by the filtration system again, so as to improve the treatment effect of the device on the fracturing return fluid. After the fine filtration system is installed, the secondary dosing device 7 is installed after the fine filtration device, and a secondary measuring instrument 8 is provided after the secondary dosing device 7. The fine filtration device includes an activated carbon filtration device 10, a primary filter 11 and a secondary filter 12. The activated carbon filtration device 10 is connected to the outlet of the backwash filtration device 6. The primary filter 11 and the secondary filter 12 are connected to the activated carbon filtration device 10 in sequence. After the liquid enters the fine filtration system, it is filtered through the activated carbon filtration device 10, the primary filter 11 and the secondary filter 12 in sequence. The activated carbon filtration device 10 uses activated carbon as the filter element, which can adsorb ions in the liquid while filtering, thereby improving the treatment effect on the liquid.
[0028] It should be noted that the filtering accuracy of the secondary filter 12 is higher than that of the primary filter 11. The liquid first passes through the primary filter 11 and then passes through the secondary filter 12 to maximize the filtering effect of the fine filtration system on the liquid. Generally, the primary filter 11 and the secondary filter 12 are both bag filters, and their filtering accuracy can be adjusted by simply replacing the filter bag. The second filtering accuracy of the primary filter 11 is generally 5μm, and the filtering accuracy of the secondary filter 11 is generally 1μm.
[0029] Combination Figure 1 The following is a detailed description of the working steps of this fracturing flowback fluid recovery and treatment system:
[0030] Step 1: Install each component on the skid-mounted base according to the system structure, and place the skid-mounted base in the working position through the lifting lugs and the on-site lifting equipment. In this process, the lifting lugs are connected to the on-site lifting equipment through lifting belts or tools such as lifting belts, and the skid-mounted base is moved to the working position by operating the on-site lifting equipment.
[0031] Step 2: Start the liquid pump to suck the fracturing return fluid, and adjust the liquid using the primary dosing device according to the measurement results of the primary measuring instrument. In this process, the primary measuring instrument measures various parameters in the liquid, selects the appropriate treatment agent according to the measurement results, and injects the agent into the liquid through the dosing device in sequence to adjust the various parameters of the liquid to the range required for the work.
[0032] Step 3: Input the liquid after drug addition into the electrocoagulation device for flocculation treatment. At this time, the electrocoagulation device energizes the liquid, and the water in the liquid is partially electrolyzed to produce hydrogen and oxygen, forming many tiny bubbles in the liquid, which act as carriers to adhere to suspended solids in the water and float up, capturing impurity particles in the fracturing return fluid; at the same time, the internal soluble anodes such as iron and aluminum, after being passed through high-voltage pulse direct current, lose electrons in the anodes, forming metal cations Fe and Al, which combine with OH in the solution to form highly active flocculation groups to adsorb and co-precipitate pollutants in the wastewater and remove them.
[0033] Step 4: Input the liquid treated by the electroflocculation device into the filtration system and fine filtration system for filtration in turn, and open the sewage outlet of the electroflocculation device to discharge the sediment into the spiral stacking machine for treatment. In this process, the liquid treated by the electroflocculation device passes through the quartz sand filter device in the filtration system, the backwash filter device, the activated carbon filter device in the fine filtration system, the primary filter and the secondary filter to filter the liquid part; at the same time, the spiral stacking machine compresses and dehydrates the sediment in the electroflocculation device to achieve solid-liquid separation, thereby improving the treatment efficiency of the device.
[0034] Step 5: Read the secondary measuring instrument and add medicine to the liquid through the secondary dosing device according to the reading of the secondary measuring instrument to perform secondary treatment on the treated liquid. In this process, the secondary measuring instrument can adjust the parameters in the treated liquid so that the liquid parameters meet the treatment requirements.
[0035] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A fracturing flowback fluid recovery and processing system, characterized in that: include: A skid-mounted base, wherein the skid-mounted base is provided with an incoming liquid pump (1), an electrocoagulation device (4) and a filtering system, wherein the filtering system comprises a quartz sand filter (5) and a backwash filtering device (6); the input end of the incoming liquid pump (1) is connected to the on-site liquid outlet, and the output end is connected to the inlet of the electrocoagulation device (4); the liquid outlet of the electrocoagulation device (4) is connected to the inlet of the quartz sand filter (5), and the outlet of the quartz sand filter (5) is connected to the inlet of the backwash filtering device (6); a primary measuring instrument (3) is provided between the electrocoagulation reaction device (4) and the incoming liquid pump (1), and a primary dosing device (2) is provided at the outlet of the primary measuring instrument (3); a secondary dosing device (7) is provided at the outlet of the filtering device, and a secondary measuring instrument (8) is provided after the secondary dosing device (7).
2. The fracturing flowback fluid recovery and processing system according to claim 1, characterized in that: A plurality of lifting ears are evenly arranged on the skid-mounted base.
3. The fracturing flowback fluid recovery and processing system according to claim 1, characterized in that: A spiral stacking machine (9) is arranged behind the electrocoagulation device (4), a sewage discharge hole is arranged at the bottom of the electrocoagulation device (4), and an inlet of the spiral stacking machine (9) is connected to the sewage discharge hole.
4. The fracturing flowback fluid recovery and processing system according to any one of claims 1 or 3, characterized in that: A fine filtration system is provided after the filtration system, the secondary dosing device (7) is located after the fine filtration system, and a secondary measuring instrument (8) is provided after the secondary dosing device (7).
5. The fracturing flowback fluid recovery and processing system according to claim 4, characterized in that: The fine filtration system comprises an activated carbon filtration device (10), a primary filter (11) and a secondary filter (12); the outlet end of the backwash filtration device (6) is connected to the activated carbon filtration device (10), the activated carbon filtration device (10) is connected to the primary filter (11) and the secondary filter (12) in sequence, and the secondary dosing device (7) is located after the output end of the secondary filter (12).
6. The fracturing flowback fluid recovery and processing system according to claim 5, characterized in that: The primary filter (11) and the secondary filter (12) are both bag filters, and the filtering accuracy of the secondary filter (12) is higher than that of the primary filter (11).
7. The fracturing flowback fluid recovery and processing system according to claim 1, characterized in that: The primary measuring instrument (3) and the secondary measuring instrument (8) are both turbidity measuring instruments.