Research On Integrated Tubular String Technology For Fracturing And Drainage Of Coal-based Gas

The research on integrated tubular string technology for fracturing and drainage of coal-based gas is used to study the reservoir-based protection column technology for coal-based gas.It has been supported by the national major science and technology special project: ―Linxing—Shenfu area coal seam gas,tight gas,shale gasification and mining demonstration project‖.(No.2016ZX05066004-002)The research is based on the analysis of gas production characteristics of coal-bearing strata and the law of gas production and gas production in gas reservoirs.From the perspective of fracturing process and drainage characteristics,combined with comprehensive comparative analysis and evaluation of existing drainage equipment.Finally,the integrated technology of fracturing and drainage is proposed.Firstly,analysis of technical characteristics of coal-based gas drainage,established an adaptive analysis process for the application of fracturing and drainage integrated pipe string technology.The two technical requirements for the integrated technology of fracturing and drainage are presented in the application of C BM wells to meet the requirements of drainage and the requirements of fracturing columns to meet the fracturing requirements.Then,under the premise of meeting the integrated technology of fracturing and drainage,the integrated pipe string technology based on the sliding sleeve sealing which is suitable for the fracturing,returning and production of coal-fired gas wells is designed.Based on the design process and the critical equipment fracturing sliding sleeve structure,through the selection of the column and the analysis of the liquid carrying capacity,obtaining the fracturing column can achieve stable drainage of coal-based gas and use ANSYS software to analyze the internal flow field.the stress value generated by the fluid in the pump is less than the allowable stress value of the material.The production string meets the requirements for coal-based gas well fracturing.Similarly,the advantages and disadvantages of the sliding sleeve plugging column technology are analyzed.The design and the on-site complete supporting integrated hydraulic column pumping technology based o n the uplift hydraulic feedback pump.By studying the force and pump displacement of the rod tube,the technology can better solve the problem that the fixed pipe column realizes the positional fracturing passage,and the pump is stably discharged after th e pressure.Ensure continuous and stable production of coalbed methane wells.Finally,through dynamic comprehensive comparative analysis and evaluation of different drainage string technologies,using the analytic hierarchy process to calculate the weight of the indicator system,and quantify the status and role of each indicator in the overall project,verification of the feasibility assessment theory,comparative analysis and evaluation of the two column technology designed,the solution is based on the fracturing and drainage integrated pipe string technology of sliding sleeve sealing,which has leading advantages for the development technology of low permeability and low pressure coal-bearing gas strata.It can meet the requirements of continuous draina ge,and reduce the number of gas well kills in the application of string technology,achieving the established goal of "reservoir protection".