Improving Reliability and Boosting Energy Efficiency of an Ammonia Plant by Revamping Natural Gas Pipe Line and Associated Compressor Train

摘要

Petrokemija's ammonia plant has been in operation since 1983 and designed to use low pressure natural gas of 7 barg (101.5 psig) at the inlet of natural gas compressor train. The new possibility to extract higher pressure natural gas of 30 barg (435.1 psig) from natural gas pipeline network triggered revamping scenario to boost the energy efficiency and improve reliability. In total, the overall natural gas consumption of ammonia plant was reduced for 1200 Sm?/h which gives 2.1 % better energy efficiency at nameplate production rate. The revamping process from concept to commissioning is presented, including planning, procurement, installation, commissioning, safety procedures and practical difficulties which encountered during startup. Although safety comes first as a part of each and every revamping process phase including developing a risk analysis matrix and HAZOP study, our experience shows that occurred leakage of natural gas during startup could jeopardize the complete plant safety, and even further steps should be taken in order to eliminate all possible risks.