Disclosed techniques include controlled liquefaction and energy management. A gas within a first pressure containment vessel is pressurized using a column of liquid. The gas that is being pressurized is cooled using a liquid spray, wherein the liquid spray is introduced into the first pressure containment vessel in a region occupied by the gas. The liquid spray keeps the pressurizing to be isothermal. The gas that was pressurized is metered into a second pressure containment vessel, wherein the metering enables liquefaction of the gas. The gas that was pressurized is stored in a gas capacitor prior to the metering. The gas that was liquefied in the second pressure containment vessel is pushed into a holding tank, wherein the holding tank stores a liquefied state of the gas, and wherein the pushing is accomplished by the pressure of the gas that was metered into the second pressure containment vessel.

The disclosure provides a method and system for optimizing production of a natural gas liquefaction process, the method comprising the steps of: selecting at least one manipulated variable (MV) for controlling the liquefaction process; selecting at least one control variable (CV), the at least one control variable at least comprising liquefied natural gas (LNG) throughput; providing at least one model, each model providing a dependency of the at least one control variable (CV) on the at least one manipulated variable (MV); using the at least one model to estimate LNG throughput for at least one of the manipulated variables (MV); obtaining process data from the liquefaction process, the process data at least including observed values of LNG throughput; creating a gain matrix based on said interdependencies; and using the gain matrix to optimize a process control system of the liquefaction process.

A method for determining an operating condition of a liquefied natural gas plant (2) includes preparing a training model (88) generated by machine learning using training data in which operating conditions data including a composition of a feed gas, a composition of a mixed refrigerant, and an ambient temperature and operation result data including a production efficiency of a liquefied product containing liquefied natural gas and a heavy component of the feed gas are associated together; and determining, 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 (88) from a latest composition of the feed gas in the liquefied natural gas plant (2) and a latest ambient temperature.

A liquefied gas cooling apparatus including: a gas flow path for carrying a liquefied gas that is liquefied by cooling; and a refrigeration unit including a refrigerating cycle formed by an evaporator for cooling the liquefied gas flowing through the gas flow path, a compressor, a condenser, and a throttle expansion unit. The compressor is driven through an electric motor contained in a sealed housing together with a compressor mechanism.

A method for controlling the flow of natural gas and refrigerant in the main heat exchanger of a natural gas liquefaction facility. The method provides for the automated control of a flow rate of a natural gas feed stream through a heat exchanger based on one or more process variables and set points. The flow rate of refrigerant streams through the heat exchanger is controlled by different process variables and set points, and is controlled independently of the flow rate of the natural gas feed stream.

Provided is a technology of searching for operation guidance for efficiently operating a liquefied natural gas plant An operation guidance searching method for a liquefied natural gas plant includes: acquiring data sets of operation data of process variables for a plurality of target devices and disturbance data; generating, through machine learning, a plant model indicating correspondences of output values of process variables with respect to manipulated variables and input values of disturbances; and searching, through reinforcement learning, for input values of the manipulated variables operation variables for with which a compression power per unit production amount is minimized under a condition in which an outlet temperature of a liquefied natural gas is a preset restriction temperature or lower.

An operation analysis method for a natural gas plant includes: acquiring production amount data of a product per unit time and operation data of a plurality of controlled devices forming the natural gas plant in association with each other along a time series; determining whether or not a controlled device that violates the operation constraint is present at the time point of acquisition of the production amount data when the production amount data is less than the reference production amount, and performing data processing of associating an item subjected to the operation constraint to the production amount data; and determining, for each of the items subjected to the operation constraints, a length of a period with the production reduction in accordance with a magnitude of the production reduction amount.

The invention relates to: a method for monitoring a process engineering installation, in which a model of the process engineering installation is used to ascertain values of at least one performance parameter of the process engineering installation from actual values of at least one operating parameter of the process engineering installation that occur during operation of the process engineering installation, wherein the model is used to ascertain comparison values of the at least one performance parameter of the process engineering installation from setpoint values of the at least one operating parameter, and wherein mutually corresponding values and comparison values of the at least one performance parameter are taken as a basis for ascertaining at least one performance gap in the operation of the process engineering installation and to a process engineering installation.

Provided is an operation analysis method for a production plant (1), including: acquiring, with use of a Doppler LIDAR (5), a distribution of three-dimensional wind condition data at positions of an upper space of the production plant (1) and a surrounding space thereof including an arrangement region for an air-cooled heat exchanger (2); acquiring environment data indicating a state of a natural environment that affects operation of the air-cooled heat exchanger (2); and learning, through a numerical analysis with use of a computer, based on a distribution of the three-dimensional wind condition data and on the environment data, a correspondence between a distribution pattern of the three-dimensional wind condition data and the environment data.

A liquefied gas cooling apparatus including: a gas flow path for carrying a liquefied gas that is liquefied by cooling; and a refrigeration unit including a refrigerating cycle formed by a compressor, a cooling unit, and an expander. The compressor is driven through an electric motor contained in a sealed housing together with a compressor mechanism.