Multi-cluster temporary plugging fracturing pitching method and temporary plugging fracturing method and system

Abstract

The invention belongs to the field of oil and gas exploitation, and particularly relates to a multi-cluster temporary plugging fracturing pitching method and a temporary plugging fracturing method and system. Under the condition that the liquid nitrogen accompanying injection pipeline is not communicated with the fracturing injection pipeline, the temporary plugging ball is put into the liquid nitrogen accompanying injection pipeline and pressurized, the plug valve is opened to communicate the liquid nitrogen accompanying injection pipeline with the fracturing injection pipeline when a certain pressure value is reached, and the temporary plugging ball is jacked into the fracturing injection pipeline through a certain pressure; therefore, the pressure difference between the ball throwing device and the fracturing injection pipeline when the ball throwing device is started can be avoided, the temporary plugging ball can enter the fracturing injection pipeline at a time, and the ball throwing temporary plugging effect is guaranteed. The ball injection system can share a liquid nitrogen accompanying injection pipeline with facilities required by liquid nitrogen accompanying injection, and the liquid nitrogen accompanying injection pipeline is connected to a plug valve of a fracturing injection pipeline and liquid nitrogen pump equipment; due to the fact that liquid nitrogen needs to be injected along with fracturing construction of the compact low-permeability sandstone reservoir at present, other ball injection auxiliary facilities do not need to be additionally arranged in the ball injection system except the ball injector, and the temporary plugging cost of ball injection is reduced.

Description

Technical Field

[0001] The invention belongs to the field of oil and gas exploitation, and in particular relates to a multi-cluster temporary plugging fracturing ball throwing method, a temporary plugging fracturing method and a system. Background Art

[0002] In recent years, fracturing transformation is an important measure to increase production in low permeability reservoirs. With the advancement of horizontal well reservoir transformation technology, in order to further expand the transformation volume, the main body of the horizontal well adopts dense cutting multi-cluster temporary plugging volume fracturing technology. In order to ensure uniform fracturing of multiple clusters, it is necessary to temporarily plug the clusters with balls; the commonly used ball throwing devices are mainly installed on the fracturing injection pipeline. When the ball needs to be thrown, the pump must be stopped first, and the ball must be thrown into the pipeline and then restarted to send the ball into the well, which affects the construction efficiency; or an electric remote-controlled ball throwing device is installed on the fracturing injection pipeline, and the ball is thrown without stopping the pump, but the temporary plugging balls enter the pipeline relatively dispersedly, and the temporary plugging pressure is not obvious after the balls are in place, resulting in poor temporary plugging effect.

[0003] For the multi-cluster temporary plugging fracturing construction of horizontal wells, in order to ensure the smooth addition of temporary plugging balls, the corresponding ball throwing device will be specially designed. For example, the Chinese invention patent with application publication number CN113294136A discloses a ball throwing device for oil field fracturing, which adopts the working mode of normal pressure counting and high pressure throwing, wherein the translation seal body adopts the translation conveying method to quantitatively transport the fracturing balls in the normal pressure area to the high pressure area and realize the release of the fracturing balls. It is suitable for various sizes of steel balls, low-density degradable balls and soluble temporary plugging ball fracturing construction. One set of equipment meets various construction requirements, withstands high pressure, and can realize the switching between automatic mode and manual mode; or as the authorization announcement number CN Chinese utility model patent No. 205532552U discloses an acid fracturing ball-dropping system, which is additionally provided with a second fluid supply vehicle and a corresponding ball-dropping fracturing vehicle, wherein a temporary plugging ball is dropped into the second fluid supply vehicle, and enters the ball-dropping fracturing vehicle through a pipeline, and after the ball-dropping fracturing vehicle pressurizes the temporary plugging ball, the temporary plugging ball passes through the pipeline into a high-pressure fracturing injection pipeline, and then is sent into the wellhead through the high-pressure fracturing injection pipeline; however, the above-mentioned two ball-dropping devices are directly installed or connected to the high-pressure fracturing injection pipeline, and when the ball is automatically dropped, due to the high pipeline pressure without stopping the pump, there is a pressure difference when the ball-dropping device is turned on, and the temporary plugging ball cannot enter the high-pressure fracturing injection pipeline at one time, which affects the temporary plugging effect of the ball-dropping. Summary of the invention

[0004] The purpose of the present invention is to provide a multi-cluster temporary plugging fracturing ball throwing method, a temporary plugging fracturing method and a system, which are used to solve the problem that the existing horizontal well multi-cluster temporary plugging fracturing construction ball throwing device needs to be installed or connected to the fracturing high-pressure fracturing injection pipeline, resulting in a pressure difference when the ball throwing device is opened, affecting the temporary plugging effect of the ball throwing.

[0005] In order to achieve the above-mentioned object, the present invention provides a multi-cluster temporary plugging fracturing ball throwing system, including a ball thrower, the ball thrower is used to connect to the liquid nitrogen accompanying injection pipeline, and is also used to install the required temporary plugging balls; and also includes a plug valve, the plug valve is used to connect the liquid nitrogen accompanying injection pipeline to the fracturing injection pipeline for fracturing injection, and is closed when the liquid nitrogen pump equipment corresponding to the liquid nitrogen accompanying injection pipeline stops pumping;

[0006] The ball thrower is also used to open when it is necessary to throw the ball and the plug valve is closed, so as to throw the required temporary blocking ball into the liquid nitrogen injection pipeline; the plug valve is also used to open when the liquid nitrogen pump equipment starts pumping and the pressure value of the pressurization is higher than the wellhead pressure and exceeds the set pressure threshold after the ball thrower throws the required temporary blocking ball into the liquid nitrogen injection pipeline, so that the liquid nitrogen pump equipment can pump the required temporary blocking ball from the liquid nitrogen injection pipeline into the fracturing injection pipeline.

[0007] The beneficial effect of the technical solution is as follows: when the liquid nitrogen accompanying injection pipeline is not connected to the fracturing injection pipeline for fracturing injection (i.e., the stopcock is closed), the temporary blocking ball is first thrown into the liquid nitrogen accompanying injection pipeline and pressurized, and the stopcock is opened until a certain pressure value is reached, and the liquid nitrogen accompanying injection pipeline is connected to the fracturing injection pipeline for fracturing injection, so that the temporary blocking ball is pushed from the liquid nitrogen accompanying injection pipeline into the high-pressure fracturing injection pipeline through a certain pressure, thereby avoiding the pressure difference between the ball throwing device and the high-pressure fracturing injection pipeline when it is opened, so that the temporary blocking ball can enter the high-pressure fracturing injection pipeline at one time, The ball throwing system can realize temporary plugging by continuously pumping and improve the construction efficiency, thereby ensuring the temporary plugging effect of the ball throwing system. The temporary plugging efficiency and success rate are greatly improved. The ball throwing system can share the liquid nitrogen injection pipeline with the corresponding facilities for liquid nitrogen injection, and connect the liquid nitrogen injection pipeline to the plug valve of the fracturing injection pipeline and the liquid nitrogen pump equipment. Therefore, when applied to the fracturing system requiring liquid nitrogen injection, there is basically no need to add other additional ball throwing equipment or ball throwing auxiliary facilities except the ball thrower, and the existing pipelines in the fracturing construction process can still be used, thereby reducing the cost of temporary plugging by ball throwing.

[0008] Furthermore, the set pressure threshold value has a value range of 2-3 MPa.

[0009] This embodiment also provides a multi-cluster temporary plugging fracturing ball throwing method, the steps are as follows:

[0010] When ball throwing is required and the plug valve is closed, the ball thrower is opened to throw the required temporary plugging ball into the liquid nitrogen accompanying injection pipeline; the ball thrower is connected to the liquid nitrogen accompanying injection pipeline and is installed with the required temporary plugging ball; the plug valve connects the liquid nitrogen accompanying injection pipeline to the fracturing injection pipeline of the fracturing injection, and is closed when the liquid nitrogen pump equipment corresponding to the liquid nitrogen accompanying injection pipeline stops pumping;

[0011] After the ball thrower throws the required temporary plugging balls into the liquid nitrogen injection pipeline, start the liquid nitrogen pump equipment. When the pressure value of the liquid nitrogen pump equipment is higher than the wellhead pressure and exceeds the set pressure threshold, open the stopcock to allow the liquid nitrogen pump equipment to pump the required temporary plugging balls from the liquid nitrogen injection pipeline into the fracturing injection pipeline.

[0012] The beneficial effect of the technical solution is as follows: when the liquid nitrogen accompanying injection pipeline is not connected to the fracturing injection pipeline for fracturing injection (i.e., the stopcock is closed), the temporary blocking ball is first thrown into the liquid nitrogen accompanying injection pipeline and pressurized, and the stopcock is opened until a certain pressure value is reached, and the liquid nitrogen accompanying injection pipeline is connected to the fracturing injection pipeline for fracturing injection, so that the temporary blocking ball is pushed from the liquid nitrogen accompanying injection pipeline into the high-pressure fracturing injection pipeline through a certain pressure, thereby avoiding the pressure difference between the ball throwing device and the high-pressure fracturing injection pipeline when it is opened, so that the temporary blocking ball can enter the high-pressure fracturing injection pipeline at one time, The ball throwing method can realize temporary plugging without stopping the pump, and ensure the effect of temporary plugging on the basis of improving construction efficiency, thereby greatly improving the temporary plugging efficiency and success rate. In addition, the ball throwing method can reuse the liquid nitrogen injection pipeline, the plug valve connecting the liquid nitrogen injection pipeline to the fracturing injection pipeline, and the liquid nitrogen pump equipment with the corresponding process of liquid nitrogen injection. Therefore, when applied to a fracturing system requiring liquid nitrogen injection, except for the ball thrower, there is basically no need to add other additional ball throwing equipment or ball throwing auxiliary facilities, and the existing pipelines in the fracturing construction process can still be used, thereby reducing the cost of temporary plugging with ball throwing.

[0013] Furthermore, the set pressure threshold value has a value range of 2-3 MPa.

[0014] The present invention also provides a multi-cluster temporary plugging fracturing system, including a ball throwing subsystem, the ball throwing subsystem includes a ball throwing device, the ball throwing device is used to connect the liquid nitrogen accompanying injection pipeline, and is also used to install the required temporary plugging balls; and also includes a plug valve, the plug valve is used to connect the liquid nitrogen accompanying injection pipeline to the fracturing injection pipeline for fracturing injection, and is closed when the liquid nitrogen pump equipment corresponding to the liquid nitrogen accompanying injection pipeline stops pumping;

[0015] The ball thrower is also used to open when it is necessary to throw the ball and the plug valve is closed, so as to throw the required temporary blocking ball into the liquid nitrogen injection pipeline; the plug valve is also used to open when the liquid nitrogen pump equipment starts pumping and the pressure value of the pressurization is higher than the wellhead pressure and exceeds the set pressure threshold after the ball thrower throws the required temporary blocking ball into the liquid nitrogen injection pipeline, so that the liquid nitrogen pump equipment can pump the required temporary blocking ball from the liquid nitrogen injection pipeline into the fracturing injection pipeline.

[0016] The beneficial effect of the technical solution is as follows: when the liquid nitrogen accompanying injection pipeline is not connected with the fracturing injection pipeline for fracturing injection (i.e., the stopcock is closed), the temporary blocking ball is first thrown into the liquid nitrogen accompanying injection pipeline and pressurized, and the stopcock is opened until a certain pressure value is reached, and the liquid nitrogen accompanying injection pipeline is connected with the fracturing injection pipeline for fracturing injection, so that the temporary blocking ball is pushed into the high-pressure fracturing injection pipeline from the liquid nitrogen accompanying injection pipeline by a certain pressure, thereby avoiding the pressure difference between the ball throwing device and the high-pressure fracturing injection pipeline when it is opened, so that the temporary blocking ball can enter the high-pressure fracturing injection pipeline at one time, The effect of temporary plugging by throwing balls is guaranteed on the basis of achieving non-stop pumping and improving construction efficiency, thereby greatly improving the temporary plugging efficiency and success rate. The ball throwing subsystem can share the liquid nitrogen accompanying injection pipeline with the liquid nitrogen accompanying injection subsystem, and connect the liquid nitrogen accompanying injection pipeline to the plug valve of the fracturing injection pipeline and the liquid nitrogen pump equipment. Therefore, when applied to a fracturing system requiring liquid nitrogen accompanying injection, there is basically no need to add other additional ball throwing equipment or ball throwing auxiliary facilities except the ball thrower, and the existing pipelines in the fracturing construction process can still be used, thereby reducing the cost of temporary plugging by throwing balls.

[0017] Furthermore, the set pressure threshold value has a value range of 2-3 MPa.

[0018] Furthermore, it also includes a fracturing injection subsystem and a liquid nitrogen co-injection subsystem;

[0019] The fracturing injection subsystem is used to operate after the fracturing construction starts and the ball injection subsystem ends, and includes a fracturing vehicle group, a high-pressure manifold and a fracturing injection pipeline; the fracturing vehicle group is used to pressurize the sand-mixing fluid; the high-pressure manifold is used to inject the pressurized sand-mixing fluid into a number of fracturing injection pipelines; the fracturing injection pipeline is used to inject the sand-mixing fluid into multiple clusters of target wells for temporary plugging and fracturing;

[0020] The liquid nitrogen accompanying injection subsystem comprises a liquid nitrogen pump device and a liquid nitrogen accompanying injection pipeline. The liquid nitrogen pump device is used to start the pump and pressurize when liquid nitrogen is needed to be injected during the operation of the fracturing injection subsystem, and when the remote control cock is opened, the liquid nitrogen is pumped into the fracturing injection pipeline through the liquid nitrogen accompanying injection pipeline, so that the liquid nitrogen and the sand mixing liquid are injected into the target wells of the multi-cluster temporary plugging fracturing together, and the pump is stopped when the accompanying injection of liquid nitrogen is not needed; it is also used to start the pump and pressurize after the ball thrower throws the required temporary plugging ball into the liquid nitrogen accompanying injection pipeline; the cock is also used to open when liquid nitrogen is needed to be injected and the liquid nitrogen pump device starts the pump and pressurizes, so that the liquid nitrogen pump device pumps the liquid nitrogen from the liquid nitrogen accompanying injection pipeline into the fracturing injection pipeline.

[0021] The beneficial effects of the technical solution are as follows: the ball throwing subsystem and the liquid nitrogen accompanying injection subsystem share the liquid nitrogen accompanying injection pipeline, and can also share the plug valve that connects the liquid nitrogen accompanying injection pipeline to the fracturing injection pipeline and the liquid nitrogen pump equipment that pumps the temporary plugging ball or liquid nitrogen into the fracturing injection pipeline; since the current fracturing construction of dense low-permeability sandstone reservoirs requires the injection of liquid nitrogen, the above-mentioned ball throwing subsystem that can share the liquid nitrogen accompanying injection pipeline, plug valve and liquid nitrogen pump equipment with the liquid nitrogen accompanying injection subsystem basically does not need to add other additional ball throwing equipment or ball throwing auxiliary facilities except the ball thrower, and can still use the existing pipelines during the fracturing construction process, thereby reducing the cost of temporary plugging by ball throwing.

[0022] The present invention also provides a multi-cluster temporary plugging fracturing method, including a temporary plugging ball throwing process, wherein the steps of the temporary plugging ball throwing process are as follows:

[0023] When ball throwing is required and the plug valve is closed, the ball thrower is opened to throw the required temporary plugging ball into the liquid nitrogen accompanying injection pipeline; the ball thrower is connected to the liquid nitrogen accompanying injection pipeline and is installed with the required temporary plugging ball; the plug valve connects the liquid nitrogen accompanying injection pipeline to the fracturing injection pipeline of the fracturing injection, and is closed when the liquid nitrogen pump equipment corresponding to the liquid nitrogen accompanying injection pipeline stops pumping;

[0024] After the ball thrower throws the required temporary plugging balls into the liquid nitrogen injection pipeline, start the liquid nitrogen pump equipment. When the pressure value of the liquid nitrogen pump equipment is higher than the wellhead pressure and exceeds the set pressure threshold, open the stopcock to allow the liquid nitrogen pump equipment to pump the required temporary plugging balls from the liquid nitrogen injection pipeline into the fracturing injection pipeline.

[0025] The beneficial effect of the technical solution is as follows: when the liquid nitrogen accompanying injection pipeline is not connected with the fracturing injection pipeline for fracturing injection (i.e., the stopcock is closed), the temporary blocking ball is first thrown into the liquid nitrogen accompanying injection pipeline and pressurized, and the stopcock is opened until a certain pressure value is reached, and the liquid nitrogen accompanying injection pipeline is connected with the fracturing injection pipeline for fracturing injection, so that the temporary blocking ball is pushed into the high-pressure fracturing injection pipeline from the liquid nitrogen accompanying injection pipeline by a certain pressure, thereby avoiding the pressure difference between the ball throwing device and the high-pressure fracturing injection pipeline when it is opened, so that the temporary blocking ball can enter the high-pressure fracturing injection pipeline at one time, The effect of temporary plugging by throwing balls is guaranteed on the basis of achieving non-stop pumping and improving construction efficiency, thereby greatly improving the temporary plugging efficiency and success rate. In addition, the temporary plugging ball throwing process can reuse the liquid nitrogen injection pipeline and the plug valve connecting the liquid nitrogen injection pipeline to the fracturing injection pipeline and the liquid nitrogen pump equipment with the liquid nitrogen injection process. Therefore, when applied to a fracturing system requiring liquid nitrogen injection, there is basically no need to add other additional ball throwing equipment or ball throwing auxiliary facilities except the ball thrower, and the existing pipelines in the fracturing construction process can still be used, thereby reducing the cost of temporary plugging by throwing balls.

[0026] Furthermore, the set pressure threshold value has a value range of 2-3 MPa.

[0027] Furthermore, it also includes a fracturing injection process and a liquid nitrogen co-injection process;

[0028] The steps of the fracturing injection process are as follows:

[0029] 1) After the fracturing operation begins, the sand-mixing liquid is pressurized by the fracturing vehicle group, and then the pressurized sand-mixing liquid is injected into several fracturing injection pipelines through the high-pressure manifold, and then the sand-mixing liquid is injected into the target wells of multiple clusters of temporary plugging fracturing through the fracturing injection pipelines;

[0030] 2) Carry out liquid nitrogen injection process and temporary plugging and ball injection process according to corresponding needs;

[0031] 3) After the temporary plugging and ball throwing process is completed, repeat the above-mentioned fracturing injection process step 1);

[0032] The steps of the liquid nitrogen injection process are as follows:

[0033] When liquid nitrogen injection is required during the fracturing injection process, the liquid nitrogen pump equipment starts the pump to pressurize, opens the remote control cock valve, and pumps liquid nitrogen into the fracturing injection pipeline through the liquid nitrogen injection pipeline, so that liquid nitrogen and mixed sand liquid are injected together into the target wells of multiple clusters of temporary plugging fracturing; when liquid nitrogen injection is not required, the liquid nitrogen pump equipment stops the pump.

[0034] The beneficial effects of the technical solution are as follows: the temporary plugging and ball-throwing process and the liquid nitrogen co-injection process share the liquid nitrogen co-injection pipeline, and also share the plug valve that connects the liquid nitrogen co-injection pipeline to the fracturing injection pipeline and the liquid nitrogen pump equipment that pumps the temporary plugging ball or liquid nitrogen into the fracturing injection pipeline. Since the current fracturing construction of dense low-permeability sandstone reservoirs requires the injection of liquid nitrogen, the multi-cluster temporary plugging fracturing method that reuses the liquid nitrogen co-injection pipeline, plug valve and liquid nitrogen pump equipment when performing temporary plugging and liquid nitrogen co-injection respectively, basically does not require the addition of other additional ball-throwing equipment or ball-throwing auxiliary facilities except the ball-throwing device, and can still use the existing pipelines in the fracturing construction process, thereby reducing the cost of temporary plugging by ball-throwing. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a structural block diagram of a multi-cluster temporary plugging fracturing system in an embodiment of the multi-cluster temporary plugging fracturing system of the present invention;

[0036] Figure 2 It is a schematic diagram of the temporary plugging effect corresponding to the second stage fracturing operation curve of the JPH-XXX horizontal well in the embodiment of the multi-cluster temporary plugging fracturing system of the present invention. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0038] Multi-cluster temporary plugging fracturing system embodiment

[0039] This embodiment provides a technical solution for a multi-cluster temporary plugging fracturing system. Figure 1 The system includes a pitching subsystem (corresponding to Figure 1 Temporary plugging and ball throwing process in the process), and also includes the fracturing injection subsystem (corresponding to Figure 1 The fracturing injection process) and liquid nitrogen injection subsystem (corresponding to Figure 1 Liquid nitrogen injection process);

[0040] The ball throwing subsystem includes a ball throwing device, which is used to connect the liquid nitrogen accompanying injection pipeline and is also used to install the required temporary plugging balls. In this embodiment, the temporary plugging balls required for temporary plugging are installed in the ball throwing device in advance; it also includes a plug valve, which is used to connect the liquid nitrogen accompanying injection pipeline to the fracturing injection pipeline of the fracturing injection, and is closed when the liquid nitrogen pump equipment corresponding to the liquid nitrogen accompanying injection pipeline stops pumping; in this embodiment, refer to Figure 1 The ball thrower used is a remote-controlled ball thrower, the plug valve used is also a remote-controlled plug valve, and the liquid nitrogen pump equipment is a liquid nitrogen pump truck.

[0041] The ball thrower is also used to open when it is necessary to throw the ball and the stopcock is closed, so as to throw the required temporary blocking ball into the liquid nitrogen accompanying injection pipeline; the stopcock is also used to open when the liquid nitrogen pump device starts pumping and the pressure value of the pressurization is higher than the wellhead pressure and exceeds the set pressure threshold after the ball thrower throws the required temporary blocking ball into the liquid nitrogen accompanying injection pipeline, so that the liquid nitrogen pump device pumps the required temporary blocking ball from the liquid nitrogen accompanying injection pipeline into the fracturing injection pipeline; in this embodiment, the set pressure threshold value range is 2-3MPa, and the stopcock can be opened when the pressure value of the liquid nitrogen pump device pressurization is higher than the wellhead pressure by 2-3MPa, so that all the temporary blocking balls in the liquid nitrogen accompanying injection pipeline are pumped into the fracturing injection pipeline at one time; because the temporary blocking balls in this embodiment are pushed into the high-pressure fracturing injection pipeline by a certain pressure, the pressure difference between the ball throwing device and the high-pressure fracturing injection pipeline can be avoided when the ball throwing device is opened, so that the temporary blocking ball can enter the high-pressure fracturing injection pipeline at one time, and the effect of temporary blocking by throwing the ball is guaranteed on the basis of realizing non-stop pumping and throwing temporary blocking balls and improving construction efficiency, thereby greatly improving the temporary blocking efficiency and success rate.

[0042] The fracturing injection subsystem is used to operate after the fracturing construction starts and the ball injection subsystem ends, and includes a fracturing vehicle group, a high-pressure manifold and a fracturing injection pipeline; the fracturing vehicle group is used to pressurize the sand-mixing fluid; the high-pressure manifold is used to inject the pressurized sand-mixing fluid into a plurality of fracturing injection pipelines (in other embodiments, only one may be provided); each fracturing injection pipeline is used to inject the sand-mixing fluid into a plurality of target wells for temporary plugging and fracturing; Figure 1As shown, the fracturing injection subsystem also includes a fracturing tank, a sand mixing truck, an injection head and a fracturing wellhead. The fracturing fluid tank supplies fluid to the sand mixing truck through a corresponding low-pressure pipeline. The sand mixing truck mixes the fracturing fluid and the proppant to obtain a sand mixing fluid, which is then pressurized by the fracturing truck group and passes through a high-pressure manifold and a fracturing injection pipeline, and then enters the target well of the multi-cluster temporary plugging fracturing through the injection head and the fracturing wellhead.

[0043] The liquid nitrogen accompanying injection subsystem includes a liquid nitrogen pump device and a liquid nitrogen accompanying injection pipeline. The liquid nitrogen pump device is used to start the pump and pressurize when liquid nitrogen is needed to be injected during the operation of the fracturing injection subsystem, and when the remote control cock is opened, the liquid nitrogen is pumped into the fracturing injection pipeline through the liquid nitrogen accompanying injection pipeline, so that liquid nitrogen and mixed sand liquid are injected into the target wells of multiple clusters of temporary plugging fracturing, and the pump is stopped when the accompanying injection of liquid nitrogen is not needed; it is also used to start the pump and pressurize after the ball thrower throws the required temporary plugging balls into the liquid nitrogen accompanying injection pipeline; the cock in the ball throwing subsystem is also used to open when liquid nitrogen is needed to be injected and the liquid nitrogen pump device starts the pump and pressurizes, so that the liquid nitrogen pump device pumps liquid nitrogen from the liquid nitrogen accompanying injection pipeline into the fracturing injection pipeline. It can be seen that the ball-docking subsystem and the liquid nitrogen injection subsystem in this embodiment share the liquid nitrogen injection pipeline, and also share the stopcock that connects the liquid nitrogen injection pipeline to the fracturing injection pipeline and the liquid nitrogen pump equipment (liquid nitrogen pump truck) that pumps the temporary plugging ball or liquid nitrogen into the fracturing injection pipeline. Since the current fracturing construction of dense low-permeability sandstone reservoirs requires the injection of liquid nitrogen, the above-mentioned ball-docking subsystem and the liquid nitrogen injection subsystem share the liquid nitrogen injection pipeline, stopcock and liquid nitrogen pump equipment. Except for the ball-docking device, there is basically no need to add other additional ball-docking equipment or ball-docking auxiliary facilities, and the existing pipelines in the fracturing construction process can still be used, thereby reducing the cost of temporary plugging by ball-docking.

[0044] In order to realize the release and drainage of fluid, the multi-cluster temporary plugging fracturing system in this embodiment also includes a release and drainage subsystem. Figure 2 The blowout and drainage subsystem includes a backflow tank and a corresponding blowout process and pipeline. The pipeline is connected from the wellhead to the backflow tank of the blowout and drainage subsystem, and a control valve group is provided on the pipeline to adjust the blowout speed, so as to provide blowout and drainage after fracturing is completed or when fracturing sand is blocked.

[0045] Taking the JPH-XXX horizontal well in a gas field as an example, the specific process of using the multi-cluster temporary plugging fracturing system described above in this embodiment to perform the second stage fracturing operation is as follows, wherein each subsystem is connected by a 3.5" equal-diameter high-pressure pipeline and a union of the same specification:

[0046] 1) Before fracturing, first place the sand mixer, fracturing truck, liquid nitrogen pump truck, high-pressure manifold, remote-controlled ball thrower, remote-controlled plug valve, 3.5” high-pressure pipeline and fracturing wellhead on the ground according to the requirements. Figure 1 Connect according to the connection relationship shown and pressure test each subsystem according to the design requirements.

[0047] 2) When the fracturing construction begins, the fracturing injection subsystem is in operation, and the fracturing fluid tank supplies fluid to the sand mixer through a low-pressure pipeline. The fracturing fluid is cross-linked and mixed with the proppant in the sand mixer. The mixed sand fluid after the fracturing fluid and the proppant are pressurized by the fracturing vehicle group and then passed through the high-pressure manifold and the 3.5” high-pressure fracturing injection pipeline (also called 3.5” fracturing injection pipeline) through the injection head and the fracturing wellhead and pumped into the target well for multi-cluster temporary plugging fracturing;

[0048] When liquid nitrogen injection is required, the liquid nitrogen injection subsystem is operated, and the liquid nitrogen pump truck starts pumping and pressurizing. At this time, the remote control cock valve in the ball injection subsystem opens, and the liquid nitrogen enters the 3.5” fracturing injection pipeline from the liquid nitrogen injection pipeline and is pumped into the well together with the sand mixing fluid.

[0049] 3) After the sand mixer has replaced 5-10 cubic meters of sand, when the ball throwing is required, the liquid nitrogen pump truck stops pumping, the ball throwing subsystem runs, and the remote control plug valve is closed. At this time, the sand mixer stops adding sand for displacement, and the remote control ball thrower is opened to throw the temporary plugging balls required for this fracturing section into the 3.5" liquid nitrogen accompanying injection pipeline at one time. Then, the liquid nitrogen pump truck is started to pressurize. When the pressure of the liquid nitrogen pump truck is 2-3MPa higher than the wellhead pressure, the remote control plug valve is opened. Under the action of liquid nitrogen, all the temporary plugging balls are pushed into the 3.5" fracturing injection pipeline. The displacement volume after the ball throwing is calculated, and the change of temporary plugging pressure is observed after the temporary plugging balls are in place, and the fracturing construction after temporary plugging is started.

[0050] 4) The fracturing construction after temporary plugging is performed in the same manner as step 2) of the operation of the fracturing injection subsystem when the fracturing construction is started.

[0051] 5) When the fracturing construction of this section is about to end, the liquid nitrogen pump truck stops pumping, the remote control plug valve is closed, the sand mixing truck stops supplying liquid, and the fracturing truck stops pumping to complete the construction of this section.

[0052] The temporary plugging effect diagram of the above fracturing construction process is shown in Figure 2 It can be seen that after the temporary blocking ball is in place, the pressure rises by 4MPa, which shows that the temporary blocking effect is obvious.

[0053] Multi-cluster temporary plugging fracturing method embodiment

[0054] This embodiment provides a multi-cluster temporary plugging fracturing method, which includes a temporary plugging ball throwing process, and the steps of the temporary plugging ball throwing process are as follows:

[0055] When ball throwing is required and the stopcock is closed, the ball thrower is opened to throw the required temporary plugging ball into the liquid nitrogen accompanying injection pipeline; wherein the ball thrower is connected to the liquid nitrogen accompanying injection pipeline, and the required temporary plugging ball is installed in advance, the stopcock connects the liquid nitrogen accompanying injection pipeline to the fracturing injection pipeline of the fracturing injection, and is closed when the liquid nitrogen pump equipment corresponding to the liquid nitrogen accompanying injection pipeline stops pumping; in this embodiment, the ball thrower used is a remote-controlled ball thrower, the stopcock used is also a remote-controlled stopcock, and the liquid nitrogen pump equipment is a liquid nitrogen pump truck.

[0056] After the ball thrower throws the required temporary plugging ball into the liquid nitrogen accompanying injection pipeline, the liquid nitrogen pump device is started. When the pressure value of the liquid nitrogen pump device is higher than the wellhead pressure and exceeds the set pressure threshold, the stopcock is opened to allow the liquid nitrogen pump device to pump the required temporary plugging ball from the liquid nitrogen accompanying injection pipeline into the fracturing injection pipeline. In this embodiment, the value range of the set pressure threshold is 2-3MPa. The stopcock can be opened when the pressure value of the liquid nitrogen pump device is higher than the wellhead pressure by 2-3MPa, and the temporary plugging balls in the liquid nitrogen accompanying injection pipeline are pumped into the fracturing injection pipeline at one time; since the temporary plugging balls in this embodiment are pushed into the high-pressure fracturing injection pipeline by a certain pressure, the pressure difference between the ball throwing device and the high-pressure fracturing injection pipeline can be avoided when the ball throwing device is turned on, so that the temporary plugging ball can enter the high-pressure fracturing injection pipeline at one time, and the effect of the temporary plugging ball throwing is guaranteed on the basis of realizing the temporary plugging of the ball throwing without stopping the pumping and improving the construction efficiency, thereby greatly improving the temporary plugging efficiency and success rate.

[0057] The method also includes a fracturing injection process and a liquid nitrogen co-injection process; the steps of the fracturing injection process are as follows:

[0058] 1) After the fracturing operation begins, the sand-mixing liquid is pressurized by the fracturing vehicle group, and then the pressurized sand-mixing liquid is injected into several fracturing injection pipelines through the high-pressure manifold, and then the sand-mixing liquid is injected into the target wells of multiple clusters of temporary plugging fracturing through the fracturing injection pipelines;

[0059] 2) Carry out liquid nitrogen injection process and temporary plugging and ball throwing process according to corresponding needs;

[0060] 3) After the temporary plugging and ball throwing process is completed, repeat the above-mentioned fracturing injection process step 1);

[0061] The specific steps of liquid nitrogen injection process are as follows:

[0062] When liquid nitrogen injection is required during the fracturing injection process, the liquid nitrogen pump equipment starts the pump to pressurize, opens the remote control cock valve, and pumps liquid nitrogen into the fracturing injection pipeline through the liquid nitrogen injection pipeline, so that liquid nitrogen and mixed sand liquid are injected together into the target wells of multiple clusters of temporary plugging fracturing; when liquid nitrogen injection is not required, the liquid nitrogen pump equipment stops the pump. It can be seen that the temporary plugging ball-throwing process and the liquid nitrogen co-injection process in this embodiment share the liquid nitrogen co-injection pipeline, and also share the plug valve that connects the liquid nitrogen co-injection pipeline to the fracturing injection pipeline and the liquid nitrogen pump equipment (liquid nitrogen pump truck) that pumps the temporary plugging ball or liquid nitrogen into the fracturing injection pipeline. Since the current fracturing construction of dense low-permeability sandstone reservoirs requires the injection of liquid nitrogen, the above-mentioned multi-cluster temporary plugging fracturing method that reuses the liquid nitrogen co-injection pipeline, plug valve and liquid nitrogen pump equipment when performing ball-throwing temporary plugging and liquid nitrogen co-injection respectively, basically does not require the addition of other additional ball-throwing equipment or ball-throwing auxiliary facilities except the ball-throwing device, and can still use the existing pipelines in the fracturing construction process, thereby reducing the cost of ball-throwing temporary plugging.

[0063] Since the specific contents of the fracturing injection process and the liquid nitrogen co-injection process in this embodiment have been respectively described in the contents of the relevant fracturing injection subsystem and liquid nitrogen co-injection subsystem of the above-mentioned multi-cluster temporary plugging fracturing system embodiment, and the overall process of the multi-cluster temporary plugging fracturing method including the fracturing injection process, the liquid nitrogen co-injection process and the temporary plugging ball throwing process has also been described in detail in the specific process of the second stage fracturing construction of the JPH-XXX horizontal well in a gas field in the above-mentioned multi-cluster temporary plugging fracturing system embodiment, it will not be repeated here.

[0064] Embodiment of multi-cluster temporary plugging fracturing ball throwing system

[0065] This embodiment provides a multi-cluster temporary plugging fracturing ball throwing system. The ball throwing system (corresponding to Figure 1 The temporary plugging ball throwing process in the process) includes a ball thrower, which is used to connect the liquid nitrogen accompanying injection pipeline and is also used to install the required temporary plugging ball; it also includes a plug valve, which is used to connect the liquid nitrogen accompanying injection pipeline to the fracturing injection pipeline of the fracturing injection, and is closed when the liquid nitrogen pump equipment corresponding to the liquid nitrogen accompanying injection pipeline stops pumping; in this embodiment, refer to Figure 1 The ball thrower used is a remote-controlled ball thrower, the plug valve used is also a remote-controlled plug valve, and the liquid nitrogen pump equipment is a liquid nitrogen pump truck.

[0066] The ball thrower is also used to open when it is necessary to throw the ball and the stopcock is closed, so as to throw the required temporary blocking ball into the liquid nitrogen accompanying injection pipeline; the stopcock is also used to open when the liquid nitrogen pump device starts pumping and the pressure value of the pressurization is higher than the wellhead pressure and exceeds the set pressure threshold after the ball thrower throws the required temporary blocking ball into the liquid nitrogen accompanying injection pipeline, so that the liquid nitrogen pump device pumps the required temporary blocking ball from the liquid nitrogen accompanying injection pipeline into the fracturing injection pipeline; in this embodiment, the set pressure threshold value range is 2-3MPa, and the stopcock can be opened when the pressure value of the liquid nitrogen pump device pressurization is higher than the wellhead pressure by 2-3MPa, so that all the temporary blocking balls in the liquid nitrogen accompanying injection pipeline are pumped into the fracturing injection pipeline at one time; because the temporary blocking balls in this embodiment are pushed into the high-pressure fracturing injection pipeline by a certain pressure, the pressure difference between the ball throwing device and the high-pressure fracturing injection pipeline can be avoided when the ball throwing device is opened, so that the temporary blocking ball can enter the high-pressure fracturing injection pipeline at one time, and the effect of temporary blocking by throwing the ball is guaranteed on the basis of realizing non-stop pumping and throwing temporary blocking balls and improving construction efficiency, thereby greatly improving the temporary blocking efficiency and success rate.

[0067] Furthermore, the ball-dropping system in the present embodiment can share the liquid nitrogen injection pipeline with the corresponding facilities required for liquid nitrogen injection, and can also share the stopcock that connects the liquid nitrogen injection pipeline to the fracturing injection pipeline and the liquid nitrogen pump equipment (liquid nitrogen pump truck) that pumps the temporary plugging ball or liquid nitrogen into the fracturing injection pipeline. Since the current fracturing construction of dense low-permeability sandstone reservoirs requires the injection of liquid nitrogen, the above-mentioned ball-dropping system and the corresponding facilities required for liquid nitrogen injection share the liquid nitrogen injection pipeline, stopcock and liquid nitrogen pump equipment except for the ball-dropping device. There is basically no need to add other additional ball-dropping equipment or ball-dropping auxiliary facilities, and the existing pipelines in the fracturing construction process can still be used, thereby reducing the cost of temporary plugging by ball-dropping.

[0068] Since the specific working mode and connection relationship of the ball throwing system in this embodiment during fracturing construction have been described in detail in the above multi-cluster temporary plugging fracturing system embodiment, they will not be repeated here.

[0069] Embodiment of multi-cluster temporary plugging fracturing ball throwing method

[0070] This embodiment provides a multi-cluster temporary plugging fracturing ball throwing method, the steps are as follows:

[0071] When ball throwing is required and the plug valve is closed, the ball thrower is opened to throw the required temporary plugging ball into the liquid nitrogen accompanying injection pipeline; the ball thrower is connected to the liquid nitrogen accompanying injection pipeline and is installed with the required temporary plugging ball; the plug valve connects the liquid nitrogen accompanying injection pipeline to the fracturing injection pipeline of the fracturing injection, and is closed when the liquid nitrogen pump equipment corresponding to the liquid nitrogen accompanying injection pipeline stops pumping; in this embodiment, the ball thrower used is a remote-controlled ball thrower, the plug valve used is also a remote-controlled plug valve, and the liquid nitrogen pump equipment is a liquid nitrogen pump truck.

[0072] After the ball thrower throws the required temporary plugging ball into the liquid nitrogen accompanying injection pipeline, the liquid nitrogen pump device is started. When the pressure value of the liquid nitrogen pump device is higher than the wellhead pressure and exceeds the set pressure threshold, the stopcock is opened to allow the liquid nitrogen pump device to pump the required temporary plugging ball from the liquid nitrogen accompanying injection pipeline into the fracturing injection pipeline. In this embodiment, the value range of the set pressure threshold is 2-3MPa. The stopcock can be opened when the pressure value of the liquid nitrogen pump device is higher than the wellhead pressure by 2-3MPa, and the temporary plugging balls in the liquid nitrogen accompanying injection pipeline are pumped into the fracturing injection pipeline at one time; since the temporary plugging balls in this embodiment are pushed into the high-pressure fracturing injection pipeline by a certain pressure, the pressure difference between the ball throwing device and the high-pressure fracturing injection pipeline can be avoided when the ball throwing device is turned on, so that the temporary plugging ball can enter the high-pressure fracturing injection pipeline at one time, and the effect of the temporary plugging ball throwing is guaranteed on the basis of realizing the temporary plugging of the ball throwing without stopping the pumping and improving the construction efficiency, thereby greatly improving the temporary plugging efficiency and success rate.

[0073] Moreover, the ball throwing method in the present embodiment can share the liquid nitrogen accompanying injection pipeline with the liquid nitrogen accompanying injection process, and can also share the plug valve connecting the liquid nitrogen accompanying injection pipeline to the fracturing injection pipeline and the liquid nitrogen pump equipment (liquid nitrogen pump truck) that pumps the temporary plugging ball or liquid nitrogen into the fracturing injection pipeline. Since the current fracturing construction of dense low-permeability sandstone reservoirs requires the injection of liquid nitrogen, the above-mentioned multi-cluster temporary plugging fracturing ball throwing method can reuse the liquid nitrogen accompanying injection pipeline, plug valve and liquid nitrogen pump equipment required for the liquid nitrogen accompanying injection process when performing ball throwing temporary plugging. Except for the ball thrower, there is basically no need to add other additional ball throwing equipment or ball throwing auxiliary facilities, and the existing pipelines in the fracturing construction process can still be used, thereby reducing the cost of ball throwing temporary plugging.

[0074] Since the specific application of the ball throwing method in this embodiment in the fracturing construction process has been described in detail in the above-mentioned multi-cluster temporary plugging fracturing system embodiment and multi-cluster temporary plugging fracturing method embodiment, it will not be repeated here.

[0075] The present invention has the following characteristics:

[0076] 1) When the liquid nitrogen associated injection pipeline is not connected with the fracturing injection pipeline for fracturing injection (i.e., the stopcock is closed), the temporary plugging ball is first thrown into the liquid nitrogen associated injection pipeline and pressurized until a certain pressure value is reached, and the stopcock is opened to connect the liquid nitrogen associated injection pipeline with the fracturing injection pipeline for fracturing injection, so that the temporary plugging ball is pushed into the high-pressure fracturing injection pipeline from the liquid nitrogen associated injection pipeline through a certain pressure, thereby avoiding the pressure difference between the ball throwing device and the high-pressure fracturing injection pipeline when it is turned on, so that the temporary plugging ball can enter the high-pressure fracturing injection pipeline at one time, and the effect of temporary plugging by throwing the ball is guaranteed on the basis of realizing the temporary plugging effect of the ball throwing without stopping the pump and improving the construction efficiency, thereby greatly improving the temporary plugging efficiency and success rate.

[0077] 2) The ball throwing system (ball throwing subsystem) and the corresponding facilities required for liquid nitrogen injection (liquid nitrogen injection subsystem) share the liquid nitrogen injection pipeline, and can also share the plug valve that connects the liquid nitrogen injection pipeline to the fracturing injection pipeline and the liquid nitrogen pump equipment (liquid nitrogen pump truck) that pumps the temporary plugging ball or liquid nitrogen into the fracturing injection pipeline; since the current fracturing construction of dense low-permeability sandstone reservoirs requires the injection of liquid nitrogen, the above-mentioned ball throwing system (ball throwing subsystem) that can share the liquid nitrogen injection pipeline, plug valve and liquid nitrogen pump equipment with the corresponding facilities required for liquid nitrogen injection (liquid nitrogen injection subsystem) basically does not need to add other additional ball throwing equipment or ball throwing auxiliary facilities except the ball thrower, and can still use the existing pipelines during the fracturing construction process, thereby reducing the cost of temporary plugging by ball throwing.

[0078] It should be understood that the above specific embodiments of the present invention are only used to illustrate or explain the principles of the present invention, but do not constitute a limitation to the present invention.

Claims

1. A multi-cluster temporary plugging fracturing ball throwing system, comprising a ball throwing device, characterized in that: The ball thrower is used to connect the liquid nitrogen accompanying injection pipeline and to install the required temporary plugging ball; it also includes a plug valve, which is used to connect the liquid nitrogen accompanying injection pipeline to the fracturing injection pipeline of the fracturing injection and is closed when the liquid nitrogen pump equipment corresponding to the liquid nitrogen accompanying injection pipeline stops pumping; The ball thrower is also used to open when it is necessary to throw the ball and the plug valve is closed, so as to throw the required temporary blocking ball into the liquid nitrogen injection pipeline; the plug valve is also used to open when the liquid nitrogen pump equipment starts pumping and the pressure value of the pressurization is higher than the wellhead pressure and exceeds the set pressure threshold after the ball thrower throws the required temporary blocking ball into the liquid nitrogen injection pipeline, so that the liquid nitrogen pump equipment can pump the required temporary blocking ball from the liquid nitrogen injection pipeline into the fracturing injection pipeline.

2. The multi-cluster temporary plugging fracturing ball throwing system according to claim 1, characterized in that: The set pressure threshold value ranges from 2 to 3 MPa.

3. A multi-cluster temporary plugging fracturing ball throwing method, characterized in that: Here are the steps: When ball throwing is required and the plug valve is closed, the ball thrower is opened to throw the required temporary plugging ball into the liquid nitrogen accompanying injection pipeline; the ball thrower is connected to the liquid nitrogen accompanying injection pipeline and is installed with the required temporary plugging ball; the plug valve connects the liquid nitrogen accompanying injection pipeline to the fracturing injection pipeline of the fracturing injection, and is closed when the liquid nitrogen pump equipment corresponding to the liquid nitrogen accompanying injection pipeline stops pumping; After the ball thrower throws the required temporary plugging balls into the liquid nitrogen injection pipeline, start the liquid nitrogen pump equipment. When the pressure value of the liquid nitrogen pump equipment is higher than the wellhead pressure and exceeds the set pressure threshold, open the stopcock to allow the liquid nitrogen pump equipment to pump the required temporary plugging balls from the liquid nitrogen injection pipeline into the fracturing injection pipeline.

4. The multi-cluster temporary plugging fracturing ball throwing method according to claim 3, characterized in that: The set pressure threshold value ranges from 2 to 3 MPa.

5. A multi-cluster temporary plugging fracturing system, comprising a ball throwing subsystem, wherein the ball throwing subsystem comprises a ball throwing device, characterized in that: The ball thrower is used to connect the liquid nitrogen accompanying injection pipeline and to install the required temporary plugging ball; it also includes a plug valve, which is used to connect the liquid nitrogen accompanying injection pipeline to the fracturing injection pipeline of the fracturing injection and is closed when the liquid nitrogen pump equipment corresponding to the liquid nitrogen accompanying injection pipeline stops pumping; The ball thrower is also used to open when it is necessary to throw the ball and the plug valve is closed, so as to throw the required temporary blocking ball into the liquid nitrogen injection pipeline; the plug valve is also used to open when the liquid nitrogen pump equipment starts pumping and the pressure value of the pressurization is higher than the wellhead pressure and exceeds the set pressure threshold after the ball thrower throws the required temporary blocking ball into the liquid nitrogen injection pipeline, so that the liquid nitrogen pump equipment can pump the required temporary blocking ball from the liquid nitrogen injection pipeline into the fracturing injection pipeline.

6. The multi-cluster temporary plugging fracturing system according to claim 5, characterized in that: The set pressure threshold value ranges from 2 to 3 MPa.

7. The multi-cluster temporary plugging fracturing system according to claim 5 or 6, characterized in that: It also includes a fracturing injection subsystem and a liquid nitrogen co-injection subsystem; The fracturing injection subsystem is used to operate after the fracturing construction starts and the ball injection subsystem ends, and includes a fracturing vehicle group, a high-pressure manifold and a fracturing injection pipeline; the fracturing vehicle group is used to pressurize the sand-mixing fluid; the high-pressure manifold is used to inject the pressurized sand-mixing fluid into a number of fracturing injection pipelines; the fracturing injection pipeline is used to inject the sand-mixing fluid into multiple clusters of target wells for temporary plugging and fracturing; The liquid nitrogen accompanying injection subsystem comprises a liquid nitrogen pump device and a liquid nitrogen accompanying injection pipeline. The liquid nitrogen pump device is used to start the pump and pressurize when liquid nitrogen is needed to be injected during the operation of the fracturing injection subsystem, and when the remote control cock is opened, the liquid nitrogen is pumped into the fracturing injection pipeline through the liquid nitrogen accompanying injection pipeline, so that the liquid nitrogen and the sand mixing liquid are injected into the target wells of the multi-cluster temporary plugging fracturing together, and the pump is stopped when the accompanying injection of liquid nitrogen is not needed; it is also used to start the pump and pressurize after the ball thrower throws the required temporary plugging ball into the liquid nitrogen accompanying injection pipeline; the cock is also used to open when liquid nitrogen is needed to be injected and the liquid nitrogen pump device starts the pump and pressurizes, so that the liquid nitrogen pump device pumps the liquid nitrogen from the liquid nitrogen accompanying injection pipeline into the fracturing injection pipeline.

8. A multi-cluster temporary plugging fracturing method, characterized in that: It includes a temporary blocking pitching process, and the steps of the temporary blocking pitching process are as follows: When ball throwing is required and the plug valve is closed, the ball thrower is opened to throw the required temporary plugging ball into the liquid nitrogen accompanying injection pipeline; the ball thrower is connected to the liquid nitrogen accompanying injection pipeline and is installed with the required temporary plugging ball; the plug valve connects the liquid nitrogen accompanying injection pipeline to the fracturing injection pipeline of the fracturing injection, and is closed when the liquid nitrogen pump equipment corresponding to the liquid nitrogen accompanying injection pipeline stops pumping; After the ball thrower throws the required temporary plugging balls into the liquid nitrogen injection pipeline, start the liquid nitrogen pump equipment. When the pressure value of the liquid nitrogen pump equipment is higher than the wellhead pressure and exceeds the set pressure threshold, open the stopcock to allow the liquid nitrogen pump equipment to pump the required temporary plugging balls from the liquid nitrogen injection pipeline into the fracturing injection pipeline.

9. The multi-cluster temporary plugging fracturing method according to claim 8, characterized in that: The set pressure threshold value ranges from 2 to 3 MPa.

10. The multi-cluster temporary plugging fracturing method according to claim 8 or 9, characterized in that: It also includes the fracturing injection process and the liquid nitrogen co-injection process; The steps of the fracturing injection process are as follows: 1) After the fracturing operation begins, the sand-mixing liquid is pressurized by the fracturing vehicle group, and then the pressurized sand-mixing liquid is injected into several fracturing injection pipelines through the high-pressure manifold, and then the sand-mixing liquid is injected into the target wells of multiple clusters of temporary plugging fracturing through the fracturing injection pipelines; 2) Carry out liquid nitrogen injection process and temporary plugging and ball throwing process according to corresponding needs; 3) After the temporary plugging and ball throwing process is completed, repeat the above-mentioned fracturing injection process step 1); The steps of the liquid nitrogen injection process are as follows: When liquid nitrogen injection is required during the fracturing injection process, the liquid nitrogen pump equipment starts the pump to pressurize, opens the remote control cock valve, and pumps liquid nitrogen into the fracturing injection pipeline through the liquid nitrogen injection pipeline, so that liquid nitrogen and mixed sand liquid are injected together into the target wells of multiple clusters of temporary plugging fracturing; when liquid nitrogen injection is not required, the liquid nitrogen pump equipment stops the pump.

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