Study On The Optimization Of Coalbed Methane Well Drainage System In Southern Sichuan Basin

The drainage system of coalbed methane wells is one of the main factors affecting the production capacity of coalbed methane.In theory,there are a variety of coalbed methane well drainage system optimization methods,but often the actual production situation is more complex and changeable,and the theoretical methods often cannot be considered comprehensively,so it is necessary to seek practical and feasible system optimization methods based on actual production conditions.Taking the coalbed methane test area in southern Sichuan Basin as an example,in view of the optimization of the coalbed methane well system,this thesis designed a three-stage well bottom flow pressure drop model,and the well bottom flow pressure drop path was matched and optimized by the nearest neighbor algorithm,which provided a new method for the selection of the pressure drop path of the new well;the method of dynamically adjusting and optimizing the pressure drop path was studied through the flow material balance curve,combined with the proposed gas production index,dynamic permeability and other parameters;the drainage alarm early warning method was established,and the feasibility of the coalbed methane well drainage system from design to adjustment and advanced adjustment optimization was explored.Coalbed methane well related production dynamics and changeable,the study shows the comprehensive use of the flow of matter balance curve and the proposed gas index,dynamic permeability and other analysis of the coalbed methane well drainage process,can be dynamically optimized and adjusted to achieve the purpose of optimizing production,the disadvantage is that it cannot be optimized quantitatively.At the same time,the thesis takes the card pump early warning as an example,indicating that the use of coalbed methane well discharge abnormal early warning,advanced optimization and adjustment of the discharge system,can effectively deal with the problem of insufficient understanding or sudden abnormality caused by the discontinuity of drainage.