SYSTEM AND METHOD FOR DERIVING STORAGE TANK OPERATION PLAN

摘要

The purpose of the present invention is to derive a feasible solution to a problem of establishing an operation plan for storage tanks for storing liquefied natural gas, which is a complex mixed-integer nonlinear problem. Assuming that initial tank-state information, receiving schedule information, and feeding schedule information are given, two processing are executed alternately two or more times, namely, a first solving processing wherein a mixed-integer nonlinear planning problem is solved by replacing the mixed-integer nonlinear planning problem with a mixed-integer linear planning problem by executing linear approximation of nonlinear formats for nonlinear constraints that include the nonlinear formats, and a temporary solution or a final solution is derived for a reception pattern that prescribes a storage tank that is to be the receiving tank of liquefied natural gas and a discharging pattern that prescribes a storage tank that is to discharge liquefied natural gas, and a second solving processing wherein a mixed-integer nonlinear planning problem is solved by replacing the mixed-integer nonlinear planning problem with a continuous nonlinear planning problem by fixing discrete variables temporarily for discrete constraints that include the discrete variables, and a temporary solution or a final solution is derived for transitions in the amount of liquefied natural gas and the amount of heat stored in each of the storage tanks.