A process for recovering valuables from vent gas in polyolefin production is disclosed. The process includes a compression cooling separation step, a heavy hydrocarbon separation step, a light hydrocarbon separation step, a N.sub.2 purification step, and a turbo expansion step in sequence. The N.sub.2 purification step comprises a membrane separation procedure. The light hydrocarbon separation step comprises at least one gas-liquid separation procedure. A first gas, which is obtained by the gas-liquid separation procedure and is heated through heat exchange with multiple streams in the light hydrocarbon separation step, enters the heavy hydrocarbon separation step and is further heated; the heated first gas then enters the N.sub.2 purification step; a first generated gas, which is obtained by the membrane separation procedure of the N.sub.2 purification step, enters the heavy hydrocarbon separation step and the light hydrocarbon separation step in sequence, and is cooled through heat exchange with multiple streams in the heavy hydrocarbon separation step and the light hydrocarbon separation step; and then the cooled first generated gas enters the turbo expansion step. The energy consumption of a compressor can be greatly reduced. An external cooling medium with a temperature lower than an ambient temperature is not needed. The purity and recovery of N.sub.2 and hydrocarbons can be improved, which can facilitate reduction of energy consumption of a whole system, an investment, and a material consumption.

A non-cryogenic system for producing high-purity nitrogen is connected to a coiled-tubing unit. The nitrogen is produced by passing compressed ambient air through two polymeric membrane modules connected in series. The output of the second module is a stream of high-purity nitrogen, which is conveyed into a coiled tube. The nitrogen can be used for inerting the interior of the tube, or the coiled tube can be inserted into an oil well, for delivering nitrogen into the well. The use of nitrogen in a coiled tube helps to prevent corrosion in the tube.

A system and method to supply nitrogen gas is provided. Ambient air is compressed and stored in a storage receiver and then nitrogen is separated from the compressed air in a nitrogen membrane separation unit. The separated nitrogen is stored in a nitrogen storage tank under pressure and released through a pressure control valve. The system is confined to a small footprint and is useful as a nitrogen source where conventional compressed nitrogen tanks are a safety or space issue. Systems to prepare nitrogen infused beverages are also provided.

A system and method to supply nitrogen gas is provided. Ambient air is compressed and stored in a storage receiver and then nitrogen is separated from the compressed air in a nitrogen membrane separation unit. The separated nitrogen is stored in a nitrogen storage tank under pressure and released through a pressure control valve. The system is confined to a small footprint and is useful as a nitrogen source where conventional compressed nitrogen tanks are a safety or space issue. Systems to prepare nitrogen infused beverages are also provided.

Methods for producing renewable ammonia are disclosed. Systems for implementing the methods are also disclosed.

An apparatus for nitrogen generation for methanol powered maritime vehicles can include a compression system for compressing air and feeding compressed air to a separation unit for separation of nitrogen and oxygen from the compressed air. The nitrogen can be output from the separation unit for storage at an elevated pre-selected pressure suitable for feeding to a methanol engine of a maritime vehicle (e.g. a ship) for use in purging, leak testing, inerting, or other uses. Embodiments can be configured so there is no heat exchanger or booster compressor positioned between the separation unit and the nitrogen storage unit.