Embodiments provide a method for preventing shutdowns in LNG facilities by removing heavy hydrocarbons from the inlet gas supply. According to an embodiment, there is provided an LNG facility treating pipeline quality natural gas that is contaminated with lubrication oil and low concentrations of heavy hydrocarbons. Due to contamination, the behavior of the pipeline quality natural gas is not properly predicted by thermodynamic modeling. In an embodiment, heavy hydrocarbons are removed by a drain system in a heat exchanger. In an embodiment, heavy hydrocarbons are removed by a treatment bed.

A system for cooling a feed stream including hydrogen or helium with a mixed refrigerant includes a pre-cooling heat exchanger. A compression system has an inlet in fluid communication with the pre-cooling heat exchanger and receives and increases a pressure of a refrigerant vapor stream including hydrogen and/or helium mixed with at least one other refrigerant such that the molecular weight of the mixture is greater than 6 kg/kgmol. The compression system has an outlet in fluid communication with the pre-cooling heat exchanger. A first refrigerant separation device receives fluid from the pre-cooling heat exchanger and has a liquid outlet in fluid communication with the pre-cooling heat exchanger and a vapor outlet. A refrigerant purifier has a purifier inlet in fluid communication with the vapor outlet of the first refrigerant separation device and an outlet in fluid communication with the pre-cooling heat exchanger.

A system for cooling a feed stream including hydrogen or helium with a mixed refrigerant includes a pre-cooling heat exchanger. A compression system has an inlet in fluid communication with the pre-cooling heat exchanger and receives and increases a pressure of a refrigerant vapor stream including hydrogen and/or helium mixed with at least one other refrigerant such that the molecular weight of the mixture is greater than 6 kg/kgmol. The compression system has an outlet in fluid communication with the pre-cooling heat exchanger. A first refrigerant separation device receives fluid from the pre-cooling heat exchanger and has a liquid outlet in fluid communication with the pre-cooling heat exchanger and a vapor outlet. A refrigerant purifier has a purifier inlet in fluid communication with the vapor outlet of the first refrigerant separation device and an outlet in fluid communication with the pre-cooling heat exchanger.

Gas processing methodology for high efficiency recovery of propane and/or ethane from a natural gas feed stream. The method is conducted without turboexpansion, and in some embodiments, without the use of a refrigeration system. A natural gas stream is processed to have gas and liquid portions. The gas portions are cooled and flow to a refluxed absorber column and the liquid portions flow to a lower pressure distillation column. Bottoms of the absorber column are depressurized into a separator, with the separator overhead vapor being used as a source of absorber column reflux. The separator liquids are fed into the lower pressure distillation column and the distillation column overhead vapor stream is used to cool the feed and/or reflux streams. The overhead vapour stream from the lower pressure distillation can be recycled to the absorber, either as a recycle or a source of reflux.

In a process for the recovery of cold from a methane-rich fluid for the cooling of a flow rich in carbon dioxide, cold is provided to a first heat exchanger for the cooling of the flow by the evaporation of an intermediate fluid by exchange of heat with the methane-rich fluid in order to form at least one condensed intermediate fluid flow at at least one pressure level; at least a part of the intermediate fluid evaporated in a second heat exchanger is condensed at at least one pressure into at least one flow.

A device includes a heat exchanger having one end connected to an air line through which air flows, and the other end connected to a hydrogen line through which liquid-state hydrogen flows. The heat exchanger is configured to produce liquid-state air as the air and the liquid-state hydrogen exchange heat with each other. The device also includes an air storage container connected to the heat exchanger via the air line and configured to store the liquid-state air discharged from the heat exchanger, and an evaporator connected to the air storage container via the air line and configured to evaporate the liquid-state air, supplied from the air storage container, through heat exchange. The device additionally includes a power generator configured to receive the air, discharged from the evaporator, via the air line, thereby producing electrical power.

One or more specific embodiments disclosed herein includes a method for separating hydrogen from an olefin hydrocarbon rich compressed effluent vapor stream, employing a single heat exchanger, multiple gas-liquid separators, multiple expander/compressor sets, and a rectifier attached to a liquid product drum.

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.

In a compression process in a dynamic compressor having at least one first and one second compression stages, a first gas having a first molecular weight of less than 10 g/mol is compressed, at least one second fluid having a second molecular weight greater than 50 g/mol is mixed with the first gas to form a third gas to be compressed having a molecular weight greater than 10 g/mol, the third gas is sent to the first compression stage, the third gas is cooled in a first heat exchanger downstream of the first compression stage, where it is partially condensed, the partially condensed third gas is sent to a first phase separator to form a fourth gas having a lower molecular weight than the third gas and a first condensed liquid having a higher molecular weight than the third gas, the fourth gas is sent from the first phase separator to the second compression stage, the fourth gas compressed in the second compression stage is sent to cool in a second heat exchanger where it partially condenses, and the partially condensed fourth gas is sent to a second phase separator to produce a fifth gas having a lower molecular weight than the fourth gas.

An anaerobic digester is provided. The anaerobic digester includes a biogas storage container comprising a semi-permeable membrane separating the biogas storage container into a first space and a second space, such that the first space is configured to be methane enriched and the second space is configured to be CO.sub.2 enriched. The anaerobic digester further includes a cover positioned over the biogas storage container for protecting the biogas storage container against the elements.