Russian Mature Fields Redevelopment

Abstract

Abstract Redevelopment of mature oil fields is becoming increasingly important in Russia and worldwide. An extensive application of new ideas, coupling reservoir management and production enhancement of mature oil fields, is outlined in this paper. Discrepancies in the pressures, production and injection data can create significant errors in reservoir simulation models. Uncertainty should be acknowledged and accounted for during the history matching and reservoir simulation process. In many cases large amounts of historical data were collected but much is either inaccurate or critical types of data have not been gathered. Lots of Russian fields have great potential using modern techniques but each project has great uncertainty due to data constraints. A strategic goal for Oil Company is mature fields redevelopment using new technology and approaches, in order to enhance oil production. Brown fields are suffering from serious reservoir management problems and field redevelopment strategies are based on significant improvement of the reservoir management and water flooding, development of new water injection patterns, which means idle producers/injectors recovery and production enhancement work on existing wells. The conclusions and recommendations of the paper include suggestions for ways to solve these problems. An understanding of historical data errors is not enough to guarantee reliable simulation models; reservoir description uncertainties and errors will always be an important driver of the model results. Introduction A project management approach was used to organize field redevelopment operation in order not to lose focus, ensuring better control over the entire process. The field redevelopment project targets the most promising blocks of the field in order to recover idle wells, stimulate existing producers, put reservoir management and waterflooding in place and perform well intervention work on wells identified through data acquisition and an assessment program. An intelligent data assessment and additional data acquisition can significantly reduce the possibility that a non accurate reservoir description will be created by trying to match unrealistic data points. Based on the findings and analysis of the data from the acquisition project, the execution phase can then be tailored to achieve maximum effect. The main goal of the data acquisition project is to show economical profitability of the execution phase in accordance with the Company economical criteria. In order to fulfill all the tasks and objectives a project team consisting of local and expatriate specialist was put in place to manage these activities. Objectives The objective of this paper is to present how the field redevelopment project was planned, project management and engineering tools used, work process description and final findings and recommendations. A field redevelopment process which includes well rehabilitation is meant to be block based, i.e. the goal is to focus on the best blocks and increase oil production by improving all areas, starting from the reservoir and finishing with well intervention work. During the macro stage of the field redevelopment it was recognized that existing data gaps were too large and would significantly influence quality of the assessment and therefore data acquisition was undertaken to ensure an acceptable level of data quality. Based on the findings and analysis of the data from the acquisition and assessment phase, the execution phase of the project was tailored to achieve maximum effect. The redevelopment project objectives are threefold: firstly, it is a field redevelopment, which will take place as a reservoir pressure support and implementation of efficient waterflooding, secondly, production management that will bring production enhancement in short period of time and thirdly, implementation of longer term reservoir management strategy. Besides the production enhancement and reservoir management objectives there is also the objective to rehabilitate idle wells and put them back into production, respecting the following principals:Optimize lifting efficiency and extend well lifeMinimize lifting costs, protect environmentImprove wellwork practice, build procedures and policy documentsIntroduce modern and cost effective data handling and data quality checkIntroduce HSE management, implement risk assessmentChange cost philosophy to cost/benefit