(390d) Study for the Optimal Operation of Natural Gas Liquid Recovery and Natural Gas Production

Natural Gas Production

Mozammel Mazumder, Qiang Xu*, Srinivas Palanki

Dan F. Smith Department of Chemical Engineering

Lamar University, Beaumont, Texas 77710, USA

Abstract

The increasing demand of energy sources has driven cryogenic natural gas liquid recovery plants to be more efficient but more complex as well. Most of the studies on the conventional natural gas liquid (NGL) process plants (Mehrpooya, et al., 2012; Khan, et al., 2014; Chebbi, et al., 2010). In this work, the gas subcooled process (GSP) was developed to overcome the problems encountered with the conventional NGL process. First, a rigorous simulation for a new natural gas liquid NGL liquefaction process is conducted. After that, the energy consumption roadmap is disclosed through in-depth thermodynamic analysis, where the opportunities for energy consumption minimization are identified. Based on the thermodynamic analysis, a rigorous optimization model is developed and solved for energy consumption reduction of the same NGL liquefaction process. The extraction of ethane and NGL from natural gas is generally based on external refrigeration, turboexpansion, Joule-Thompson expansion, and absorption. For the developed NGL liquefaction process, the overall optimization result shows that 936 KW of total compressor brake power is saved compare with base case, accounting for near 8.45% savings. It shows that the condenser duties are also reduced 1,046 KW which accounts for about 6.56% condenser duties consumption. The COP for base case is 1.39. It increases to 1.53 after optimized, which also indicates the liquefaction process efficiency is improved after optimization. The present work is directed to improving the economics and efficiency of the process for the recovery of NGL.

References

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