Studied On Development Performance Of Maokou Group Gas Reservoir Of Kongtan Gas Field In Shunan Region

Maokou Group gas reservoir of Kongtan gas field is a water-bearing gas reservoir. There are four stages, which are stability production, degression, dewatering and water-flooded, in its development process. With the gas reservoir development process further, a range of issues emerged gradually because of the water that severely restricted the development of gas reservoir.Based on comprehensive analysis and evaluation of production performance data of last 30 years, this paper have deeply recognized the gas reservoir static and dynamic characteristics, recheck the gas reservoir, Considered of the gas remaining reserves and its distribution and analysed of the relationship of water and gas and the characteristic of the water out. Then generalized the main key what restricted the development of the gas reservoir. To improve the ultimate recovery of gas reservoirs and developing effective for Kong well 6 system of Maokou Group gas reservoir of Kongtan gas field.This paper obtained the following understanding:1. The reservoir of Kongtan structure is controlled by palaeokarstic affection and current structure.2. The reservoir of Kongtan structure is made up by frac and cave.3. Base on the dynamic analysis of Kong well 6 system, this paper concluded three kinds of dynamic features for the development that is WGR Growth, WGR Stable and WGR Decrease type.4. The characteristic of water out is included selective water out and fault water out. And the formation water flowed through frac and fault.5. Base on the development of dynamic data, this paper reviewed the geologic reserve for the Moukou Group by drawdown method. Its geologic reserve is 26.36×108m3 and Kong well 6 system's gas reserve is 20.15×108m3.6.Based on its production characteristics,this paper have comprehensive analysis and summary of the main problems which to constraint the development of the Moukou Group gas reservoir.The first one: The gas production rate of the gas reservoir ,which take the method is control water gas production, is too fast to cause formation water stay in well bottom and decline the gas production.The second one: The water is restricted outlet so affect the gas reproduction.7. According to gas reservoir development features and distribution of remaining reserves,this paper proposed three sets of reproduction programs. The first one: Implementation of drainage in Kong well 11 and Kong well 13,then the Kong well 6 system resumed full production when gas breakthrough in Kong well 11 and Kong well 13.The second one: Implementation of drainage in the whole Kong well 6 system,then resumed reproduction;The third one:resumed reproduction in Kong well 11 and Kong well 13 after implementation of drainage in Kong well 21 and Kong well 6 which had smaller workload.The best reproduction programs is the first one.