Enhancing NGL Recovery Through Utilized Design Margins

In line with our quest to improve performance, optimize efficiency, and increase profitability, ADNOC Gas Processing is committed to ensure process design optimization by following best practices that add significant value to its gas business and industry. This report will outline how we were able to increase our C3+ recovery and thus the NGL production of BuHasa Train 2 by safely utilizing the existing design envelope and available design margins. Although, operating a plant beyond its design capacity is not a new concept, process and HSE assessments are a must before proceeding. These efficiency enhancements can be implemented without any capital investment and also strengthen a plant's readiness to deal with any future challenges in plant performance. In gas processing plant such as NGL extraction, process fluid pressure is an important factor which can affect the plant characteristics. The influence of different values of pressure drop in various equipment needs to be realized as it can affect the quality and quantity of the process outputs. An in-house feasibility study has been conducted to evaluate the possibility of increasing the HP compressor discharge pressure by 1 bar over its current operating pressure. The study indicated that it was possible to enhance the train's efficiency by increasing C3+ recovery, leading to an increase in NGL production and therefore a profitability increase. The study was completed after the plant facilities were comprehensively evaluated for process safety and operability, as well as analyzed improvements in terms of C3+ recovery and NGL production. A successful "Field Test Run" for 10 days were conducted to validate the predictions of the study to operate the HP compressors at 1 bar higher. The product specification, quantity and plant operating costs are important parameters and balancing them will determine the optimum pressure distribution in the process and consequently realize our benefits. Hence, during the test run, the revised operating conditions were implemented and achieved safely without any major modification or upset to the facilities. As a result, the following cost benefits were realized: C3 + Recovery increased by around ≈ 0.2 wt.%NGL production increased by around ≈ 35 Ton/dayRevenues increased by around ≈ 2.8 MM US$/YearOperating cost increased by around≈ 220000 US$/Year