Evaluation Method Of Remaining Life Research Of Production And Injection Wells In Gas Storage

With the increasing national demand for natural gas,gas storage as an important facility to ensure the supply of natural gas in cities is becoming more and more important.The safety of injection and production Wells in gas storage is an important condition to ensure the efficient operation of gas storage and the safety of surrounding residents.Different from oil and gas Wells,reservoir injection-production Wells always maintain high formation pressure and do not decrease with the increase of production year.Therefore,it is very important to accurately evaluate the residual life of gas reservoir injection-production Wells.As DZT reservoirs gas storage as an example,through actual production test data,the gas storage injector-producer corrosion rate prediction method has carried on the contrast research,the gas storage injector-producer commonly used casing residual strength calculation method was studied,established a gas storage injector-producer residual life evaluation method,forming a set of applicable to the construction site of gas storage injector-producer residual life evaluation process.(1)The mechanism of casing corrosion in gas reservoir injection-production Wells is analyzed.The casing corrosion rule of injection-production well in gas reservoir is analyzed by statistic of field test data.Three calculation methods of casing corrosion rate of injection-production well in gas reservoir are used to calculate the actual data of gas reservoir.(2)Establish the casing residual strength model of gas reservoir injection-production well,and use ABAQUS software to analyze the residual strength rule of the casing residual strength of gas reservoir injection-production well under different corrosion forms(uniform corrosion,local corrosion and pitting corrosion).It provides theoretical support for ultimate residual strength and ultimate residual wall thickness of casing.(3)Combined with the calculation results of GB/T 20657-2011 and the finite element numerical simulation results,the residual strength of the casing in the injection-production well in DZT gas reservoir was analyzed.The residual strength and ultimate wall thickness of the production casing of gas reservoir injection-production well under the condition of ultimate internal pressure and ultimate external extrusion force are obtained.According to the standard and field experience,the reference calculation method of other types of casing is given.(4)Calculate the residual life of the sample well with different methods,and evaluate the residual life calculation methods.Based on the field experience,a set of residual life evaluation method and evaluation flow of injection-production well in gas storage reservoir using dynamic prediction method is established.With this method,the residual life of three injection-production Wells in DZT gas reservoir is calculated by an example.The evaluation method of residual life of injection-production Wells in gas reservoir provides reference and guidance for the formulation of subsequent standards and field practice.