Accelerating the Shift to a Next-Generation ESP Deployment: Cable Deployed Through Tubing Electrical Submersible Pump TTESP Application

Abstract

Most Malaysian oil production is heavily reliant on gas lift. Aging assets experience declining lifting efficiencies due to depleting reservoir pressure and increase in water cut. This impact PETRONAS' capability to deliver national hydrocarbon production targets. New developments and further improvements to gas lift facilities are likely to erode the economic value of assets without even considering the potential time impact due to the complexity in delivering gas compression upgrades or gas import projects. PETRONAS' primary goal within Malaysia is to sustain production and maximize the remaining recoverable reserves. To realize this target it is widely acknowledged that the company must think differently. Alternatives to gas lift have been considered for rejuvenation of brownfield assets and development of marginal assets using a ‘fit for purpose' approach resulting in some relatively low Capital Expenditure (CAPEX)/Operating Expenditure (OPEX) solutions. One such method identified was Through Tubing Electrical Submersible Pumps - Cable Deployed (TTESP-CD). TTESP-CD technology is a game changer that can challenge the boundaries of traditional engineering with a truly rig-less deployment of an ESP system with full compliance to API/ISO requirements and demonstrating up to 70% cost savings over conventional offshore ESP installation methods. The TTESP-CD innovation helps in improving the asset value through gas prioritization, gas lift reallocation, flaring reduction and increase in lifting efficiency. TTESP-CD is also in line with the company digitalization concept due to the baseline data available from surface and downhole equipment. This technology has been declared a success through pilot deployment in an offshore field within the Sarawak Basin with an incremental gain of 250BOPD, 0.3MMSTB in reserves acceleration and 22 months run life as of Feb 2019. This has been a key step for building confidence in the wider application of the technology. Lessons learnt and best practices from the pilot implementation have been applied to ongoing and future projects and serve as a good foundation for further development of the technology. To date, approximately 20 candidates for the TTESP-CD application have been identified for replication in Malaysia within the next 2 years across 3 regions. There are various challenges faced when implementing this technology on aging offshore assets that was never designed for ESPs which include; space availability for deployment equipment and surface electrical equipment, power availability and distribution, instrumentation, data transmission, structural integrity and operational mind set. PETRONAS sees a bright future for TTESP-CD application and technology which includes layer to layer matrix dump flood, interim production and well unloading/DST well unloading.

Rigorous review of electrical submersible pump failure mechanisms and their mitigation measures

“…The ESP assembly can be placed downhole through different methods and techniques all of which have their advantages and drawbacks Gorbunov 2017;Liley and Maclean 2018;Zamanuri et al 2019). The most common methods to place the ESP assembly downhole are as follows:…”