定容气藏非均衡开采方式的研究

A STUDY OF UNBALANCE DEVELOPMENT FOR CLOSED GAS RESERVOIR

本文给出定容气藏动态预测的新模型：两区互补物质平衡法。它考虑了气藏开采中高产区和低产区之间区域性压力差异和区域间的气量补给，是对传统物质平衡法的一种修正。利用新的数学模型研究了陕甘宁盆地中部气田在不同井网和开发指标下的生产动态以及区域间补给量的变化规律，说明非均质气藏区域间压力差异造成的气窜是影响气田动态的重要因素。对于低渗透气田，在满足一定稳产年限和总产量水平的条件下，为了提高开发的经济效益，应当适当提高区域间非均衡开采程度，即在高产区多打井，利用高产区的井采出一部分低产区的天然气。

A new model is given for the production behavior of a closed gas reservoir.It considers the gas exchange between high and low production regions,caused by the pressure difference.It is an improvement of the traditional material balance method.With this new model,the production behavior of the central gas field under different well patterns and development index and the behavior of the exchange rate between regions were studied.This made it clear that the gas exchange,caused by regional pressure differences,is a very important factor for the performance of a gas reservoir.For a low permeability gas reservoir with a fixed steady production period and total output,its unbalance degree of development should be increaced to improve its economic efficiency.This means more wells should be drilled in the high production region so that part of gas in the low permeability region can be produced by the wells in the high production region.