«Automation and Informatization of the fuel and energy complex»

Energy costs optimization of LNG production in arctic conditions

UDC: 66.011
DOI: 10.33285/2782-604X-2022-7(588)-5-14

Authors:

¹ National University of Oil and Gas "Gubkin University", Moscow, Russia

Keywords: optimization of LNG production, selection of mixed refrigerant composition, process simulation, natural gas, Yamal, C3MR, SQP, UniSim

Annotation:

The article presents the results of optimization of liquefied natural gas (LNG) production applying the modernized C3MR technology for operation on the Yamal peninsula in the arctic climate. The technological model was built in UniSim Design simulation environment using Peng-Robinson equation as the equation of state. For optimization, deterministic algorithm SQP (sequential quadratic programming) was chosen and for its implementation the open via SciPy library in Python programming language was used. For accounting of technological and physical limitations, nonlinear constraints on heat exchange and compressor equipment were added to the optimization problem. Based on the optimization results, 12 optimal operation modes were selected for each month and the optimization results were compared with the published propane flow optimization results. The comparison results showed an overall energy savings of 14 % compared with earlier published optimization results.

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