Systems and methods for separating a biogas or other gaseous material into its constituent parts, including solid methane and carbon dioxide, using liquid nitrogen in a processing chamber. The individual parts may be extracted from the processing chamber. Separation and extraction can be performed on a mobile processing plant.

In a method for compressing a gas that is to be separated in a low-temperature CO.sub.2 separation unit using at least one partial condensation step and/or at least one distillation step, the gas that is to be separated has a variable composition and/or variable flow rate, the gas that is to be separated is compressed in a compressor to produce a compressed gas and the inlet pressure of the gas that is to be separated, entering the compressor, is modified according to the CO.sub.2 content and/or the flow rate of the gas that is to be separated so as to reduce the variations in volumetric flow rate of the gas that is to be separated entering the compressor.

A system and methods for processing a feed gas in a column are provided herein. A method includes feeding a feed gas into a port of a sleeve disposed around at least a portion of a periphery of the column. The sleeve includes a space between an outer wall of the column and an inner wall of the column. The sleeve releases the feed gas into the column through an opening disposed at an opposite end of the sleeve from the port.

A system and method for treating associated gas in which a stream of raw gas is passed through safety valving, an inlet pressure control mechanism, and an inlet scrubber. Pressure/temperature data is transmitted to a control system via pressure and temperature transducers. The raw gas is sent to a gas compressor to generate pressurized gas, which is sent to an aerial cooler and a chiller heat exchanger, in which a chilling media contacts the pressurized gas. The chilled pressurized gas is sent to a vapor liquid separator to generate processed gas, which is routed through either a system backpressure valve or a pressure reducing recycle valve that directs the processed gas to the inlet scrubber. The processed gas that has passed through the system backpressure valve is delivered as fuel or routed through a backpressure regulating recycle valve that directs the processed gas to a system inlet pressure reducing valve.

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.

The invention relates to a refrigeration system that in mode 1 prepares a reservoir of cooled refrigerant before flowing unconditioned gas through the system, and in mode 2, continuously cools feed gas with the prepared refrigerant inventory, extracting natural gas liquids (NGLs) comprising predominantly ethane, propane, butane, and condensate and controlled by a control system without needing ramp up time.

An expander and motor-compressor unit is disclosed. The unit includes a casing and an electric motor arranged in the casing. A compressor is arranged in the casing and drivingly coupled to the electric motor through a central shaft. Furthermore, a turbo-expander is arranged for rotation in the casing and is drivingly coupled to the electric motor and to the compressor through the central shaft.

Techniques and systems for separating components of a mixture of compressed gases each having different boiling points are described. One example system includes multiple recovery stages that each recover one of the gases by condensing it into liquid form. The recovery stages are chained together, such that each stage recovers a gas having a boiling point that is higher than those of the gases to be recovered in downstream stages. Each stage typically includes a warming element that is fluidly coupled to a condenser element that provides a surface cooled to a temperature low enough to condense one of the gases, but high enough such that the remaining gases remain in gaseous form. The system may include an initial evaporator stage that heats a liquid solution of phytochemical extracts and multiple solvents, thereby recovering the extracts and producing the mixture of gaseous solvents.

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.

An atmospheric water harvesting system includes a water-harvesting unit with an air mover and a heat exchanger. The water-harvesting unit may also include one or more screens on which water can condense. The water-harvesting unit is supplied by a coolant pathway, in which a non-cryogenic fluid coolant flows. A cryogenic cell is in the coolant pathway. The cryogenic cell receives the fluid coolant and removes heat from it by causing or allowing a controlled heat transfer between the fluid coolant and a first cryogen sealed within an inner vessel in the cryogenic cell. The coolant may be a liquid at operating temperatures, and the cryogenic cell may cool it to an appropriate temperature without a phase change, essentially acting as a “cold battery” to remove heat from the coolant.