Adaptability Analysis Of Horizontal Well Development In SD Gas Field

In recent years, the increasing demand for natural gas urges petroleum engineers to make tremendous effort. In the progress of geological exploration, low permeability or tight gas reservoirs occupy a considerable proportion of the discovered gas reservoirs. So tight gas resource shows its great potential, and it has become a major resource base of increasing reserves and production for our country and even the world. For such type of gas reservoirs, the prospective development results cannot be achieved by adopting conventional developing methods. However, horizontal wells show their incomparable superiority than vertical wells. The making a development adaptability analysis of horizontal wells and the further study of reasonable development technical countermeasures would take full advantage of horizontal wells development more.This paper targeted horizontal wells of D block in S gas reservoir, which is a low permeability and tight gas reservoir. Based on full research literature home and abroad, it analyzed the development adaptability of these horizontal wells mainly employing gas reservoir engeeneering methods. At last, the reasonable development technical countermeasures were proposed.First, dynamic reserves of horizontal wells in tight gas reservoir were calculated, and it could be found that the results were small, mainly because of the poor physical properties of the reservoir itself and strong heterogeneity of that, leading to a small coverage.Then the deliverability was computed and evaluated, including single point test, the deliverability analysis of horizontal wells of low permeability and tight gas reservoir with the consideration of kickoff pressure gradient and slippage effect, the deliverability analysis of fractured horizontal wells with the consideration of the reservoir fracturing and analysis of trinomial deliverability equation determined by production performance. Supplemented by numerical simulation methods, the main factors affecting the deliverability of horizontal wells were studied in details, and accordingly some pieces of advice were put forward that we could take measures, such as increasing the horizontal length and the fracture length within reasonable limits, as well as protecting reservoir, to increase gas production and improve recovery efficiency.Next, combined with the geological data and development situation of these horizontal wells, adaptive analysis of exploitation by horizontal wells were carried out with the result of a set of technical indicators for being suitable for horizontal well development and the conclusion that D block is suitable for horizontal well development.Finally, aimed at the current situation that D block has not realize large scale production by horizontal wells, this paper initially investigates technical countermeasures in low permeability and tight gas reservoir under the condition of large scale production by horizontal wells based on the research literature home and abroad.This paper aimed at horizontal wells of D block in S gas reservoir and the results contribute to effective and reasonable development of this block. It also can provide guidance and reference for the same gas reservoirs developed by horizontal wells.