Coal seam hydraulic fracturing and proppant conveying integrated device

Abstract

The utility model belongs to the technical field of coal mine underground hydraulic fracturing, and particularly relates to a coal seam hydraulic fracturing and proppant conveying integrated device. The device comprises a water storage tank and a sand mixing box, the water storage tank is provided with two water outlet ends which are connected with an upper water outlet pipeline and a lower water outlet pipeline respectively, the lower water outlet pipeline is connected with the sand mixing box, and the upper water outlet pipeline is directly connected with a three-way valve I; an intelligent sand adding device is installed at the top end of the sand mixing box, a sand outlet pipeline is arranged on one side of the sand mixing box and connected with a three-way valve I, the water outlet end of the three-way valve I is connected with a screw fracturing pump, the water outlet end of the screw fracturing pump is connected with two high-pressure pipelines in parallel through a three-way valve II, and a water outlet of one high-pressure pipeline is connected with a hydraulic fracturing drill rod. And a water outlet of the other high-pressure pipeline is connected with an intelligent proppant conveying nozzle. According to the on-site condition, fracturing is conducted firstly, then the propping agent is conveyed into the crack, the conveying efficiency is improved, time is saved, damage to the hydraulic fracturing water jet cutter is reduced, and economic losses are reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of underground hydraulic fracturing in coal mines, and particularly relates to an integrated device for coal seam hydraulic fracturing and proppant transportation. Background Technique

[0002] As a high-quality clean energy in the new era, the development and utilization of coalbed methane can not only make up for the shortage of resources such as conventional natural gas, but also reduce the occurrence of accidents such as gas explosions during coal mining. At present, the main method for increasing the production of coalbed methane is hydraulic fracturing technology. Nowadays, in order to reduce the damage of fracturing fluid to the coal matrix, clear water or slickwater fracturing systems are mostly used, and the proppant matching with it has become the key to research. For low-permeability coal seams, hydraulic fracturing is the most effective way to increase permeability in coalbed methane development. Hydraulic fracturing injects proppant into the coal seam through the sand-carrying fluid. After the fracture closes, the effective support of the proppant can improve the conductivity of the fracture, thereby improving the migration ability of coalbed methane.

[0003] Research shows that the migration characteristics of proppant in hydraulic fractures directly determine the stimulation effect and the productivity of coalbed methane after fracturing. At present, the proppant is mainly transported into the fracture through hydraulic fracturing equipment. On the one hand, it is difficult to evenly transport the proppant in the fracture, and it is difficult to form a good support effect. On the other hand, some proppant particles are larger in size, which may block the water jet and cause equipment damage. Therefore, it is urgent to carry out research on coal seam proppant transportation to meet the needs of hydraulic fracturing support. Content of the Utility Model

[0004] The technical problem to be solved by the utility model is to provide an integrated device for coal seam hydraulic fracturing and proppant transportation, which can, according to the on-site situation, first perform fracturing and then evenly transport the proppant into the fracture to play a supporting role, solve the problem of large-size proppant blocking the water jet, improve the proppant transportation efficiency, evenly transport, improve the proppant support effect, improve the gas drainage efficiency and the safety of coal seam mining.

[0005] The adopted technical solution is as follows:

[0006] An integrated device for coal seam hydraulic fracturing and proppant transportation includes a water storage tank and a sand mixing tank. The water inlet end of the water storage tank is connected to a water source. The water storage tank has two water outlet ends, which are respectively connected to an upper water pipeline and a lower water pipeline. The lower water pipeline is connected to the sand mixing tank, and the upper water pipeline is directly connected to a three-way valve I;

[0007] An intelligent sand adding device is installed at the top of the sand mixing tank. A sand outlet pipeline is arranged on one side of the sand mixing tank. The sand outlet pipeline is connected to the three-way valve I. The water outlet end of the three-way valve I is connected to a screw fracturing pump. The water outlet end of the screw fracturing pump is connected in parallel to two high-pressure pipelines through a three-way valve II. The water outlet of one of the high-pressure pipelines is connected to a hydraulic fracturing drill pipe, and the water outlet of the other high-pressure pipeline is connected to an intelligent proppant delivery nozzle.

[0008] Preferably, one-way check valves are respectively provided on the upper water outlet pipeline and the lower water outlet pipeline; a screw pump is further installed on the lower water outlet pipeline, and the screw pump is located on the lower water outlet pipeline between the one-way check valve and the sand mixing tank.

[0009] Preferably, a stirrer is installed on the sand mixing tank. The intelligent sand adding device is in the shape of an hourglass, and a water level detector is further provided.

[0010] Preferably, the intelligent sand adding device adds an appropriate amount of proppant into the sand mixing tank according to the set water-sand ratio.

[0011] Preferably, a multi-item controller and a flowmeter are provided on the pipeline between the screw fracturing pump and the three-way valve II.

[0012] Preferably, one-way check valves are provided on each high-pressure pipeline.

[0013] Preferably, a pressure gauge is provided on each high-pressure pipeline.

[0014] Preferably, the diameter of the spray holes of the intelligent proppant delivery spray head is 1-3 mm.

[0015] Preferably, a pressure sensor is provided at the front end of the intelligent proppant delivery spray head.

[0016] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0017] The integrated device for coal seam hydraulic fracturing and proppant delivery of the present utility model is connected in parallel with two high-pressure pipelines through a three-way valve II. The water outlet of one high-pressure pipeline is connected to a hydraulic fracturing drill pipe, and the water outlet of the other high-pressure pipeline is connected to an intelligent proppant delivery spray head. Through a multi-item controller, according to the on-site situation, it is possible to first perform fracturing and then uniformly deliver proppant into the fracture. The proppant is immediately delivered after the drilling is completed, improving the delivery efficiency. When adding proppant to the sand mixing tank, there is no need to calculate, only need to add materials, saving time, and can also improve the uniformity of proppant delivery, improve the support effect, reduce the damage of the hydraulic fracturing water jet, and reduce economic losses.

[0018] Through the two one-way check valves of the water storage tank, it is possible to arbitrarily select hydraulic fracturing to create a fracture or enter the sand mixing tank to deliver proppant.

[0019] By connecting the water inlet end of the screw pump to the water tank and the water outlet end to the sand mixing tank, the device can be reasonably arranged.

[0020] By providing one-way check valves on each high-pressure pipeline, the reverse flow of fracturing water can be prevented.

[0021] Through the intelligent sand adding device, the time cost of calculation can be saved, and only the materials need to be added and the sand ratio needs to be set.

[0022] Two high-pressure pipelines are connected in parallel through a three-way valve, enabling flexible selection between hydraulic fracturing for creating fractures and proppant transportation.

[0023] Through the intelligent proppant delivery nozzle, uniform delivery of proppant within the coal seam fractures can be achieved. Brief Description of the Drawings

[0024] Figure 1 It is a schematic structural diagram of the present utility model.

[0025] In the figure, 1 is a water storage tank; 2-1 is a one-way check valve on the upper water outlet pipeline, 2-2 is a one-way check valve on the lower water outlet pipeline; 3 is a screw pump; 4 is a sand mixing tank; 5 is a stirrer; 6 is an intelligent sand adding device; 7-1 is a three-way valve Ⅰ, 7-2 is a three-way valve Ⅱ; 8 is a multi-item controller; 9 is a flowmeter; 10-1, 10-2 are pressure gauges; 11-1, 11-2 are one-way check valves on the higher pipeline; 12 is an intelligent proppant delivery nozzle; 13 is a drill pipe; 14 is a high-pressure pipeline; 15 is a spray hole; 16 is a fracturing screw pump. Detailed Embodiments

[0026] The drawings are only for illustrative purposes. Some well-known structures and their descriptions in the drawings may be omitted. Therefore, it should not be construed as a limitation to the present utility model; the orientation names "upper", "lower", "left", "right", "front", "side", etc. are only descriptions of specific orientations and are not limited to the descriptions in the embodiments. "First", "second", "Ⅰ", "Ⅱ", etc. are only for distinction and do not specifically refer to certain technical features.

[0027] The following detailed embodiments are only used to further illustrate the present application and should not be construed as a limitation to the protection scope of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content. The devices or materials not described in detail in the present utility model can be obtained by conventional methods in the prior art.

[0028] Embodiment 1

[0029] As Figure 1 shown, an integrated device for coal seam hydraulic fracturing and proppant transportation includes a water storage tank 1 and a sand mixing tank 4. The water inlet end of the water storage tank 1 is connected to a water source. The water storage tank 1 has two water outlet ends, which are respectively connected to an upper water outlet pipeline and a lower water outlet pipeline. The lower water outlet pipeline is connected to the sand mixing tank 4, and the upper water outlet pipeline is directly connected to the three-way valve Ⅰ 7-1. A one-way check valve 2-1 is provided on the upper water outlet pipeline, and a one-way check valve 2-2 is provided on the lower water outlet pipeline; a screw pump 3 is also installed on the lower water outlet pipeline, and the screw pump 3 is on the lower water outlet pipeline between the one-way check valve 2-2 and the sand mixing tank 4.

[0030] An intelligent sand adding device 6 is installed at the top of the sand mixing box 4, and a stirrer 5 is also installed. The intelligent sand adding device 6 is in the shape of an hourglass and is also provided with a water level detector, which can sense the water volume and add an appropriate amount of proppant into the sand mixing box according to the set water-sand ratio. An out-sand pipeline is arranged on one side of the sand mixing box 4. The out-sand pipeline is connected to a three-way valve I 7-1. The water outlet end of the three-way valve I 7-1 is connected to a screw fracturing pump 16. The water outlet end of the screw fracturing pump 16 is connected in parallel to two high-pressure pipelines 14 through a three-way valve II 7-2. The water outlet of one of the high-pressure pipelines 14 is connected to a hydraulic fracturing drill pipe 13, and a one-way check valve 11-2 and a pressure sensor 10-2 are provided. The water outlet of the other high-pressure pipeline 14 is connected to an intelligent proppant delivery spray head 12, and a one-way check valve 11-1 and a pressure sensor 10-1 are provided.

[0031] A multi-item controller 8 and a flowmeter 9 are arranged on the pipeline between the screw fracturing pump and the three-way valve II. The opening and closing of the three ends of the three-way valve I 7-1 and the three-way valve II 7-2 can be controlled by controlling the multi-item controller 8, so as to flexibly select between the hydraulic fracturing task and the proppant delivery task.

[0032] The reading of the flowmeter 9 can accurately control the water pressure and flow rate, and further control the effects of hydraulic fracturing and proppant delivery. The intelligent proppant delivery spray head 12 is cylindrical, with a diameter of 40 mm, a width of 50 mm, and a spray hole diameter of 2 mm. A pressure sensor (omitted in the figure) is arranged at the front end of the intelligent proppant delivery spray head 12, and its uniform movement in the coal seam fracture can be controlled through the pressure sensor.

[0033] The spray holes of the intelligent proppant delivery spray head can transport all mine-used proppants without clogging the holes.

[0034] The working process of an integrated device for coal seam hydraulic fracturing and proppant delivery:

[0035] Install an integrated device for coal seam hydraulic fracturing and proppant transportation in the roadway. Connect the water inlet of the water storage tank 1 to the water pipe in the mine roadway. Close the one-way check valve 2-2 on the lower water outlet pipeline of the water storage tank 1, open the one-way check valve 2-1 on the upper water outlet pipeline of the water storage tank 1, and turn on the fracturing screw pump 16. Through the multi-controller 8, open the one-way check valve 11-2 on the high-pressure pipeline for hydraulic fracturing, close the one-way check valve 11-1 on the high-pressure pipeline for proppant transportation, set an appropriate flow rate, put the drill pipe 13 into the hydraulic fracturing borehole to perform the hydraulic fracturing task. After completing the hydraulic fracturing task, turn off the fracturing screw pump 16, close the one-way check valve 2-1 on the upper water outlet pipeline of the water storage tank 1, open the one-way check valve 2-2 on the lower water outlet pipeline of the water storage tank 1, turn on the screw pump 3 to make the water in the water storage tank 1 enter the sand mixing tank 4. Add proppant into the intelligent proppant sand adding device 6, set the sand ratio, add the proppant with the appropriate sand ratio into the sand mixing tank 4, turn on the stirrer 5, after stirring for a certain time, turn on the fracturing screw pump 16. Through the multi-control controller 8, open the one-way check valve 11-1 on the high-pressure pipeline for proppant transportation, close the one-way check valve 11-2 on the high-pressure pipeline for hydraulic fracturing, put the intelligent proppant delivery nozzle 12 into the borehole, and control its uniform movement in the fracture through the pressure sensor 10-1 to transport the proppant. After the transportation is completed, turn off the water pipe switch in the mine roadway, the fracturing screw pump 16, the fracturing pump 3, and all valves in sequence, and then connect to the roadway gas drainage pipeline to carry out the gas drainage work.

[0036] Embodiment 2

[0037] An integrated device for coal seam hydraulic fracturing and proppant transportation includes a water storage tank 1 and a sand mixing tank 4. The water inlet end of the water storage tank 1 is connected to a water source. The water storage tank 1 has two water outlet ends, which are respectively connected to the upper water outlet pipeline and the lower water outlet pipeline, and the lower water outlet pipeline is connected to the sand mixing tank 4.

[0038] The difference from the embodiment is that the intelligent proppant delivery nozzle 12 is cylindrical, with a diameter of 40 mm, a width of 50 mm, and a spray hole diameter of 3 mm. Other parts not mentioned are the same as those in Embodiment 1.

[0039] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions, or substitutions made by those skilled in the art within the scope of the essence of the present invention should also fall within the protection scope of the present invention.

Claims

1. An integrated device for coal seam hydraulic fracturing and proppant transportation, characterized in that: It includes a water storage tank and a sand mixing tank. The water inlet end of the water storage tank is connected to a water source. The water storage tank has two water outlet ends, which are respectively connected to an upper water outlet pipeline and a lower water outlet pipeline. The lower water outlet pipeline is connected to the sand mixing tank, and the upper water outlet pipeline is directly connected to a three-way valve Ⅰ; An intelligent sand adding device is installed at the top of the sand mixing tank. A sand outlet pipeline is arranged on one side of the sand mixing tank. The sand outlet pipeline is connected to the three-way valve Ⅰ. The water outlet end of the three-way valve Ⅰ is connected to a screw fracturing pump. The water outlet end of the screw fracturing pump is connected in parallel to two high-pressure pipelines through a three-way valve Ⅱ. The water outlet of one of the high-pressure pipelines is connected to a hydraulic fracturing drill pipe, and the water outlet of the other high-pressure pipeline is connected to an intelligent proppant delivery nozzle.

2. The integrated device for coal seam hydraulic fracturing and proppant transportation according to claim 1, characterized in that, One-way check valves are respectively arranged on the upper water outlet pipeline and the lower water outlet pipeline; A screw pump is also installed on the lower water outlet pipeline, and the screw pump is on the lower water outlet pipeline between the one-way check valve and the sand mixing tank.

3. An integrated device for coal seam hydraulic fracturing and proppant transportation according to claim 1, characterized in that, A stirrer is installed on the sand mixing tank. The intelligent sand adding device is in the shape of an hourglass, and a water level detector is also provided.

4. An integrated device for coal seam hydraulic fracturing and proppant transportation according to claim 3, characterized in that, The intelligent sand adding device adds an appropriate amount of proppant into the sand mixing tank according to the set water-sand ratio.

5. The integrated device for coal seam hydraulic fracturing and proppant transportation according to claim 1, characterized in that, A multi-item controller and a flowmeter are arranged on the pipeline between the screw fracturing pump and the three-way valve Ⅱ.

6. The integrated device for coal seam hydraulic fracturing and proppant transportation according to claim 1, characterized in that, One-way check valves are arranged on each of the high-pressure pipelines.

7. The integrated device for coal seam hydraulic fracturing and proppant transportation according to claim 1, characterized in that, Pressure gauges are arranged on each of the high-pressure pipelines.

8. The integrated device for coal seam hydraulic fracturing and proppant transportation according to claim 1, wherein For the intelligent proppant delivery nozzle, the diameter of its spray holes is 1 - 3 mm.

9. The integrated device for coal seam hydraulic fracturing and proppant transportation according to claim 1, characterized in that, A pressure sensor is arranged at the front end of the intelligent proppant delivery nozzle.

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