Optimizing Hydraulic Jet Pump Using Empirical Volumetric Efficiency Equation and Approaching NozzleThroat Combination Ratio in Sembakung Area, Indonesia

Abstract

Sembakung Area is mature structure which discovered in 1975. It is situated in North Kalimantan, around 50 miles from Tarakan island and currently undertaken by PT Pertamina EP since 2013. During 30 years of operation, many types of artificial lift trial have been used, such as ESP, rod pump, and hydraulic jet pump. Considering the structure has a massive sand problem, and moreover, the area itself is located in a remote and swampy area, rig mobilization and operations are very costly and hard to operate. As a result, a rig-less well service is needed and HJP is one of the obvious choice. Earlier, in the design of HJP in Sembakung, the size of nozzle and throat used is not common and not following the general rule, causing the general HJP design software commonly  sed cannot predict accurately the actual condition and find the optimal design for optimal production. The study presented herein describes how to find the problem that led to inaccuratibility of software used.

In the design process, it was found that Volumetric Efficiency equation (from M.B. Standings) that commonly used in designing HJP cannot be applied to Sembakung structure. Thus, an empirical Volumetric Efficiency equation should be made to design HJP specifically used for use in this structure. The uncommon nozzle and throat combination itself can be approached from the method which will be discussed herein. This method is proved to be able to find the ratio of the HJP nozzle-throat combination in Sembakung with the highest efficiency and relatively faster.