Study On Gas Reservoir Engineering Of JHS Low Permeability Gas Reservoir

The characteristic of JHS gas reservoir is low porosity and low permeability, gas production as a whole is in the rising period, but gas wells more than half have already entered into the decline period, the productivity and production of gas wells decline rapidly in this period. JHS gas reservoir is the main production reservoir of gas field, it is necessary to do research of reasonable development technical limits of JHS. this can improve development scheme, increase gas reservoir production, also can provide guidance for production of the whole gas field.This paper takes JHS gas reservoir as the research object, based on extensive researches of development in reservoir of low permeability home and abroad, combined with the geological characteristics and the actual development situation of JHS, using gas reservoir engineering method, to calculate and analyze the productivity, the law of diminishing, the abandonment pressure, oil recovery, gas well dynamic reserve, the liquid carrying critical production of gas reservoir, did research of reasonable development of technology policy based on gas reservoir engineering results:optimized the design of horizontal well, analyzed and calculated reasonable production pressure difference and yield calculation of single well, divided the development reservoir system, determined the reasonable gas production speed, well spacing pattern, well type, well spacing density, well spacing. Obtained the following conclusions:1. Through calculating and analyzing, verified the feasibility of closed gas reservoir flowing material balance equation in low permeability gas reservoirs, and achieved good results.2. For this gas reservoir, reasonable length of horizontal section in horizontal well is600m-800m, it is suitable for horizontal well drilling in the gas layer thickness below60m, the smaller the thickness of gas is, the shorter the optimal horizontal section length is; when the reservoir has no bottom water, horizontal section of the horizontal well should be located in the middle of reservoir.3. The critical liquid carrying capacity of single well in gas reservoir finally determined is1.7950×104m3/d. And chose Li Min model and Wang Yizhong model to calculate and evaluate the critical liquid carrying of JHS gas reservoir.4. Reasonable production of single well of JHS gas reservoir ultimately determined is2.58×104m3/d, the value of this gas reservoir is36.07×104m3/d. Through analyzing and comparing, the dynamic production method is recommended to analyze the reasonable production allocation. 5. Gas reservoir should use a set of layer series of development, JHS gas reservoir should use straight wells and horizontal wells combined in well selection; well spacing density of well type of JHS gas reservoir recommended is0.5666/km2.This formed an integrated engineering research method suitable for this kind of gas reservoir, provide guidance for the development of this kind gas field.