Coalbed methane high-power pulse fracturing developing device

Abstract

The invention relates to a coalbed methane high-power pulse fracturing developing device which comprises an explosion initiating device 1, wherein the explosion initiating device 1 is connected with a high pressure gas gun device 2; the high pressure gas gun device 2 is connected with a first bearing-type gas device 4 by a first switching connecting piece 3; the first bearing-type gas device 4 is connected with a second bearing-type gas device 6 by a second switching connecting piece 5; the end of the second bearing-type gas device 6 is provided with a combustible guide body 8; a combustible baffle 7 is positioned between the second bearing-type gas device 6 and the combustible guide body 8; fracturing explosive matching composition with higher burning speed and lower burning speed is adopted by the bearing-type gas devices which are controlled by time delay igniters inside the switching connecting pieces; and multi-stage high power pulse pressure is formed by continuously releasing high-temperature and high-pressure gas energy, and continuous fracturing is carried out on the coal stratum for a plurality of times, so that the fracture of the coal stratum is promoted to rapidly extend and expand, a longer multi-crack system is generated and formed, and the aim of increasing the yield of a coalbed methane well can be achieved.

Description

technical field [0001] The invention relates to a production stimulation technology for coal bed gas fracturing development, in particular to a coal bed gas strong pulse fracturing development device. technical background [0002] my country's coalbed methane resource reserves are very rich, ranking third in the world, but the utilization rate is very low. Most coal gas beds have low permeability, low pressure, and low water saturation. Coal fields rich in coal bed gas are mostly characterized by complex structures and severe coal damage, making development difficult. At present, there are mainly cave methods and hydraulic fracturing methods to improve the permeability of coal seams, including: vertical well casing perforation completion, clean water sand fracturing, active water sand fracturing, cave completion and other processes and air drilling, nitrogen Foam fracturing, clean fracturing fluid, gelatinized sand fracturing, and carbon dioxide injection have been studied ...

AI Technical Summary

Problems solved by technology

However, it is difficult to generate cracks in the gas layer far from the main fracture, the permeability and porosity of the gas layer are basically not affected, the ground stress and temperature basically do not change, and the pressure change is limited to the vicinity of the main fracture, and it is difficult to form a coalbed methane desorption environment and conditions, coalbed methane is also difficult to desorb, so some wells decay quickly after hydraulic fracturing, and repeated fracturing is also difficult to change

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