Acid gas is removed from a high pressure feed gas that contains significant quantities of CO2 and H2S. In especially preferred configurations and methods, feed gas is contacted in an absorber with a lean and an ultra-lean solvent that are formed by flashing rich solvent and stripping a portion of the lean solvent, respectively. Most preferably, the flash vapors and the stripping overhead vapors are recycled to the feed gas/absorber, and the treated feed gas has a CO2 concentration of less than 2 mol % and a H2S concentration of less than 10 ppmv, and more typically less than 4 ppmv.

Plant and process for separation of sulfur-containing components, H.sub.2S, COS and mercaptans from methanol which is used as absorbent within the Rectisol process by hot regeneration of the methanol laden in the absorption and an additional step for separation of the mercaptans from the methanol by stripping.

The invention includes a gas processing system for transforming a hydrocarbon-containing inflow gas into outflow gas products, where the system includes a gas delivery subsystem, a plasma reaction chamber, and a microwave subsystem, with the gas delivery subsystem in fluid communication with the plasma reaction chamber, so that the gas delivery subsystem directs the hydrocarbon-containing inflow gas into the plasma reaction chamber, and the microwave subsystem directs microwave energy into the plasma reaction chamber to energize the hydrocarbon-containing inflow gas, thereby forming a plasma in the plasma reaction chamber, which plasma effects the transformation of a hydrocarbon in the hydrocarbon-containing inflow gas into the outflow gas products, which comprise acetylene and hydrogen. The invention also includes methods for the use of the gas processing system.

The invention relates to a process and plant for purifying a raw synthesis gas containing hydrogen and carbon monoxide as target components and carbon dioxide and sulfur components as disruptive components by gas scrubbing with a physically acting, liquid scrubbing medium selective for carbon dioxide and sulfur components. The process/the plant comprise an absorption apparatus, a hot regeneration apparatus, a preferably multistage flash regeneration apparatus and a reabsorber column supplied with the first portion of a stripping gas. According to the invention the flash regeneration apparatus is supplied with the second portion of the stripping gas

The invention provides a process for removing organic constituents from a gas stream in a two-stage scrubbing operation, in which scrubbing is performed firstly with an alcoholic scrubbing medium and then with an aqueous scrubbing medium. The laden scrubbing media obtained can be used in certain (chemical) processes.

A process for treating a gaseous effluent obtained from a pyrolytic decomposition of one or more polymers, including: a condensation step, in a condensation chamber maintained at a first pressure, of a gaseous effluent placed in contact with an absorbent liquid, the temperature of the absorbent liquid being below the temperature of the gaseous effluent, a step of partial vaporization, by expansion of the condensate in a chamber maintained at a second pressure below the first pressure, a reinjection step which includes at least partly redirecting a first liquid or vapor fraction, obtained on conclusion of the partial vaporization step, to the condensation chamber, and a recovery step including purification of a second liquid or vapor fraction, obtained on conclusion of the partial vaporization step and charged with monomer(s).

Embodiments of the invention are directed to methods, processes, and systems for safely and reliably purifying hydrogen from a gas mixture containing hydrogen and oxygen.

The disclosure provides seven integrated methods for the chemical sequestration of carbon dioxide (CO.sub.2), nitric oxide (NO), nitrogen dioxide (NO.sub.2) (collectively NO.sub.x, where x=1, 2) and sulfur dioxide (SO.sub.2) using closed loop technology. The methods recycle process reagents and mass balance consumable reagents that can be made using electrochemical separation of sodium chloride (NaCl) or potassium chloride (KCl). The technology applies to marine and terrestrial exhaust gas sources for CO.sub.2, NOx and SO.sub.2. The integrated technology combines compatible and green processes that capture and/or convert CO.sub.2, NOx and SO.sub.2 into compounds that enhance the environment, many with commercial value.

The invention relates to a process and a plant for removing thiols from synthesis gas. Thiols and optionally thiophene and carbon disulfide are absorbed in a dedicated absorption stage with methanol as physical absorption medium. Methanol laden with at least thiols is freed of thiols in a stripping stage with methanol vapours as stripping gas and the methanol vapours-containing thiols are freed of methanol in a scrubbing stage. The process according to the invention minimizes methanol losses and the amounts of coolant required for the process.

The present invention relates to a method for upgrading biogas generated by a biological process wherein at least carbon dioxide is removed from the bio-gas. More specifically the present invention relates to method for upgrading a biogas comprising a first absorption step wherein the liquid effluent is subjected to a second absorption step and a flash step and the gas streams resulting therefrom are recycled. The present invention also relates a biogas upgrading plant.