Application of the Jet Pump to the Slim Hole Production Wells at Onshore Thailand

Abstract This is a case study to establish the positive result of an artificial lift application of the jet pump (JP) system using the coiled tubing (CT) and the macaroni tubing (MT). It is applied to the monobore completions for the slim-hole production wells on BURAPA-A oil field, onshore Thailand, implemented by Siam Moeco Ltd. (SML, Affliated Company of Mitsui Oil Exploration Co., Ltd.). As a result of the JP introduction, the resulting production decline rate was lower and the recovery factor more than doubled, which extended field life longer than expected. SML succeeded in discovering the method to minimize the capital cost while maximizing the oil recovery with the JP system. This method has given us the chance to conduct a smaller-scale well intervention operation with only minor modification of the wellhead. We believe that it is an adequate artificial lift application for the small-size oil field. Some important lessons for the small pipe size operations were learned in this process. A pin-hole leak was detected in the CT for the main production well due to erosion and corrosion by continuous high-pressure pumping for around two years after the installation of the JP completion. After reviewing the new completion design, the type of deployment pipe was converted to the MT, which is thicker and has higher integrity than the CT. Consequently, there have been no integrity issues for the deployment pipes since the production was resumed with the new completion. In addition, using the multi finger caliper tool, it was detected that the thickness of the production tubing at the jetting area was significantly eroded, showing that the JP system has the possibility to risk the integrity for the outer string. The JP completion is a validated technology to apply for the slim-hole monobore completions to increase the recovery factor and minimize the implementation cost. In addition, the well integrity risk by the JP application to the slim-hole monobore completions was revealed, and new insights were gained, resulting in some pros and cons comparing the two types of the deployment pipes (CT & MT).