Preventing, Mitigating, or Stopping Lost Circulation in Dammam Formation, South Rumaila Field, Iraq; Requires Engineering Solutions, the Best Treatments Strategies, and Economic Evaluation Analysis

摘要

Lost circulation is a challenging problem to be prevented or mitigated in the Dammam formation. Major progress is made to detect lost circulation and how to combat it. This paper describes the study of lost circulation events in more than 75 wells in South Rumaila field. Data are analyzed to determine the best ranges for key drilling parameters and provide the best remedial strategies, which have the greatest chance of mitigating or preventing this problem. Real field data (e.g. MW, ECD, Yp, RPM, SPM, and ROP) at the time of each event are recorded along with the lost circulation remedies attempted, and the outcome of those remedies. Practical field information from South Rumaila field and range of sources are reviewed and summarized to develop an integrated methodology and flowchart for handling lost circulation events in this zone. This paper will be extended work along with previous comprehensive statistical study and sensitivity analysis models about the Dammam formation. In addition, economic evaluation analysis is conducted for partial, severe, and complete losses to obtain the best field procedures. Proactive approaches are made prior entering the Dammam formation to prevent or mitigate the occurrence of the lost circulation. A broad statistical work, primitive mechanisms, typical drilling fluid properties, and recommended operational drilling parameters are estimated to use during drilling through this zone. Moreover, corrective actions are determined for each kind of the mud losses to provide efficient remedies, minimize non-productive time, and reduce cost. The best lost circulation strategy to the Dammam formation is concluded and summarized depending on a comprehensive statistical work, the most important courses of the international oil companies, technical papers, textbooks, and economic analysis evaluation to determine successful remedies for each type of the losses. These treatments are classified by relying on the mud losses classifications to avoid unwanted consequences due to inappropriate actions. In addition, engineered solutions and practical techniques are developed, which will contribute to give clear image and coherent understanding in regard this complicated and costly problem in the Dammam formation. This study will present a unique compilation of information regarding traditional approaches and the latest approaches to lost circulation control. The work attempts to provide useful guidelines and effective solutions for all situations in terms preventive measures, remedial methods, and analytical economic study. In addition, due to the lack of published studies in regard the Dammam formation, this work can serve as a vigorous resource for drilling through this zone.