Method and system for determining operating conditions of liquefied natural gas plant

A system for determining an operating condition of a liquefied natural gas plant including a main cryogenic heat exchanger configured to generate liquefied natural gas from a light component of a feed gas via heat exchange between the light component and a mixed refrigerant, a tank configured to store the liquefied natural gas, and a compressor configured to be driven using some of the feed gas and the liquefied natural gas as fuel and compress the mixed refrigerant, the system comprising:

• a processor configured to execute processing to determine an operating condition of the liquefied natural gas plant, wherein
• the processor is configured to:
• prepare a training model generated by machine learning using training data in which operating conditions data including a composition of the feed gas, a composition of the mixed refrigerant, and an ambient temperature and operation result data including a production efficiency of the liquefied natural gas are associated together, the training data including plant operation data obtained by a previous operation of the liquefied natural gas plant, in a case where there is insufficient plant operation data, the plant operation data being supplemented with the plant simulation data obtained on the basis of a simulation model for simulating an operating situation of the liquefied natural gas plant, and
• determine, as one new operating condition, a composition of the mixed refrigerant that optimizes a production efficiency of the liquefied natural gas predicted by the training model from a latest composition of the feed gas in the liquefied natural gas plant and a latest ambient temperature,
• wherein an operation assistance screen is generated for displaying the operating condition to an operator,
• the operation assistance screen includes a temperature profile of the light component and the liquefied natural gas in the main cryogenic heat exchanger, and
• the operation assistance screen includes a display region that displays the temperature profile of the main cryogenic heat exchanger, and a current value and an optimal value for temperatures of the light component, the liquefied natural gas, and mixed refrigerant gas are displayed in two rows above and below one another in the display region.