Study On Influencing Factors And Treatment Countermeasures For Low Yield And Inefficient Wells In Linxing Tight Gas Reservoir

Linxing Gas Field is a typical tight gas reservoir with low porosity and permeability.With the continuous expansion of the gas field production capacity,the gas wells those put into production in the early stage gradually enter declining production stage,with increasing water production appearing a number of low yield and inefficient wells.Therefore,in this paper,a research for 57 wells in Linxing gas reservoir has been observed.The research has discussed production law for those wells basing on the dynamic and static data,and also combining the gas reservoir engineering method.The low yield and inefficient wells among them have also been identified.While,causes and corresponding treatment measures for those low yield and inefficient wells has been discussed.Firstly,clarification production dynamic characteristics for wells have been obtained by calculating the production feature,decline law and dynamic reserves.Based on gray relational mathematics algorithm,by which those 57 wells has also been classified.Accordingly,different properties in production for various wells have been mastered by analyzing the production indexes for different types of gas wells,on the basis of the above classification result.Moreover,a rapid discrimination standard has been established for low production and inefficient wells,and 40 wells are identified as low yield and inefficient wells.Secondly,formation mechanism have been grasped by analyzing geology factors,production factors and engineering factors.Causes for low yield and inefficient wells have also been identified by adopting the single well production characteristics and inflow dynamic curve.Furthermore,production factors have been proved as common causes for low yield and inefficient wells in this paper,among which the vast majority reason is water production in gas wells for yield and inefficient wells(accounting for 87.5%).Lastly,relating measures have been proposed in response to the causes of low yield and inefficient gas wells.While the purpose have been achieved for improving the recovery factor in the gas reservoir,by fracturing modification,layer by layer combined production,coiled tubing sand flushing,natural gas catalytic infrared heating,geological intermittence,foam drainage,plunger gas lift,velocity string,foam drainage and auxiliary intermittence,mechanical pumping drainage and liquid nitrogen drainage.