Production Scheduling Optimization Of Large-scale Plunger Gas Lift Wells

With the increasing degree of natural gas extraction in China,the production of many gas wells continues to decrease,the flow rate continues to decrease,making the bottom of the well energy is not enough to carry all the accumulated liquid out of the wellbore,thus greatly affecting the production of gas wells so that gas wells become low-producing and inefficient wells,the current domestic and foreign methods to deal with such wells,the plunger gas lift process is low-cost,easy to maintain,while achieving better results in improving production and cleaning up the wellbore fluid,the application of It is widely used.However,the current production scheduling of plunger gas lift wells is mainly based on manual planning and decision-making,which is difficult to meet the actual production needs when the size of the well group increases,and there is no professional scheduling software to assist,which has the problems of low efficiency,poor real-time and unsatisfactory scheduling results.As a raw material supply point,it has become an important hot topic to improve the operational efficiency,improve and optimize the production system of switching wells,better utilize the advantages of the plunger gas lift process to achieve high economic efficiency,and how to achieve synergistic production with downstream information interchange.In this paper,the key relationships in the scheduling of single-well and cluster production operations of plunger gas lift are investigated by using dynamic and static data of plunger gas lift wells in combination with data-driven related algorithms to find the intrinsic connections of key parameters,so as to construct a single-well process model and a cluster collaborative production scheduling model,and optimize the operation scheduling strategy based on the scheduling model,as follows.(1)Starting from the actual situation of plunger gas lift wells in the Sulig field,important parameters from the historical database in the early stage of development and production were used to classify gas wells into three categories to facilitate subsequent classification modeling and operation;after that,a single-well process model was built using a tandem hybrid modeling approach to cope with the missing mechanism of the relationship between casing pressure and switch-off and production in plunger gas lift single-well production.(2)The MINLP(mixed integer nonlinear programming,MINLP)model for production scheduling of well clusters is constructed by adopting an expression based on discrete-event description with the total operating cost minimization as the objective function and constraint limits in terms of production,pressure,and time,etc.The feasibility of the model is demonstrated by combining cases and considering the The downstream influence on the production operation is considered,and a cooperative production strategy is given.(3)Since the described problem is an NP-hard problem,it is difficult to obtain a scheduling solution in a short time by conventional solvers.