Research On Development Countermeasure Of Relatively Rich Water Area Reservoir In JingBian Gas Field

With the enlarging gas productivity and increasing numbers of gas wells with underground water,more and more attention have been paid to the development countermeasure of gas reservoir with water.The main characteristics of JingBian gas field is of low pressure,low permeability,low abundance,strong heterogeneity and so on.Aiming at the actual problem during the development of Ma5₁₊₂gas reservoir in Nan2 Block of JingBian gas field,the distribution of the "relatively rich water area "and the gas reservoir engineering are studied in this article.The main points are as follows:(1)According to the dynamical production of producing wells,the geological analysis of Nan2 area and the gas reservoir engineering method,a useful way to identify the different types of formation water is brought forward.Based on the research above,this paper has analysed the mechanism of produced water and the rule of gas production.(2)On the basis of the reservoir property and the distribution of the water and gas in Ma5₁₊₂reservoir in ChangQing JingBian gas field,this article has made research on the distribution rules of the "relatively rich water area" and the influential factor of gas production.This paper gets some conclusions that the distribution rules of the relatively rich water zone is affected by regional structure,local structure, barrier for the change of the reservoir and so on.(Including the influence of the corroded fluting)(3)From the analysis of the single factor which impact the critical liquid carrying gas production rate,we can know that the critical liquid carrying flow rate will be reduced if the tubing inside diameter be shortened.For the water-yielding gas well which the carrying capacity is deficient,we can consider making use of the macaroni tubing string to extract gas by water drainage and process continuous production on condition that keeping the production rate is above the critical liquid carrying flow rate.Then the gas well can keep on utilizing self-energy to produce gas along with water continuously.(4)According to the characteristics of the gas reservoir in Nan2 block in JingBian gas field,a reservoir model of Ma5₁₊₂is established,and digital simulation is performed to match the production performances.At last,a rational forecasts of the development performance is proposed.The main technical development strategies are:â‘ For the limited "relatively rich water area",which has lower water energy,we should keep the daily gas production greater than the required minimal gas production to drain water by the energy of itself.â‘¡For the larger "relatively rich water area",we should drain the water manually to decrease the pressure of internal water body.At the edge of the water zones,we should control the gas production rate to keep the equilibrium of the pressure difference between "relatively rich water area" and pure gas areas,for the purpose of keeping the water production lower and gas production higher.â‘¢The present well pattern is imperfect,and we should add more production wells to improve the well pattern.Combined with the geological conditions of the study area,5 new gas production wells and 3 additional prospect wells are proposed.