Construction process for gas producing system in oil well layer

The invention provides a construction process for a gas producing system in an oil well layer, and relates to the technical field of oil well single-well production increase. The construction process comprises the following steps that: firstly, anti-gas channeling agents are used for sealing and blocking the high-permeability formation; the construction effect reduction due to the onrush of gas producing agents injected in the later period can be prevented; two kinds of gas producing agents capable of producing CO2 through reaction are used and are sequentially injected into the formation, so that a great amount of generated CO2 is mixed with crude oil in the formation; the formation energy is increased; the organic blockage and the inorganic blockage of a near-well zone are relieved; the oil-water fluidity ratio is improved; and the permeability of the near-well zone is improved, so that the goal of improving the single-well productivity is achieved. The construction process can better solve the problems of corrosion and scale formation on oil well equipment, pollution on a gas source, storage and transportation and environment and the like during the CO2 throughput process can be well solved; and the advantages of simple construction, low cost, safety, environment protection and the like are realized.