A process and a plant for purifying a crude gas stream containing sulfur components and hydrocarbons by gas scrubbing using a scrubbing medium which is selective for sulfur components in an absorption column. Heavy hydrocarbons and heavy mercaptans are removed from the crude gas in a lower section of the absorption column and the resulting, loaded scrubbing medium stream is fed separately from the other loaded scrubbing medium streams to a hot regeneration column. A vapor stream enriched in water, hydrocarbons and sulfur components is obtained as overhead product from the hot regeneration column and this stream is cooled to below its dew point and is separated in a gas-liquid-liquid phase separation apparatus. The resulting, organic liquid phase contains heavy hydrocarbons and heavy mercaptans and can thus be discharged from the process or the plant, as a result of which accumulation thereof in the scrubbing medium is prevented.

A process and an apparatus for dehumidifying a moist gas mixture are provided. The apparatus for dehumidifying a moist gas mixture can be used and in the process. The absorption medium used in the process and the apparatus is also provided.

A system for high-value utilization of organic solid waste includes an anaerobic digestion unit, a biogas measurement and collection unit and a methane purification and liquefaction unit. The anaerobic digestion unit includes an organic solid waste pretreatment system and an anaerobic digestion device. The biogas measurement and collection unit includes a gas flow meter and a high-pressure biogas collection device. The methane purification and liquefaction unit includes a high-pressure separation tank, a liquefaction pretreatment system, a heavy hydrocarbon and benzene removal device, a two-stage rectification system, a low-temperature pressure liquid storage tank device and a buffer storage tank. The organic solid waste undergoes an anaerobic digestion treatment to produce methane followed by collection, purification and liquefaction.

A natural gas liquefaction process combined with a synthesis gas production process. At least one part of the heat source required in the synthesis gas production process is provided by at least a portion of the regeneration stream utilized to pretreat the natural gas to be liquefied.

Systems comprising a composition where an imidazole is tethered to an amine and a solvent are described herein. Methods of their preparation and use are also described herein. The methods of using the systems include the reduction of volatile compounds from gas streams and a liquid stream.

An absorbent for selective removal of hydrogen sulfide over carbon dioxide from a fluid stream comprises an aqueous solution of a) a tertiary amine, b) a sterically hindered secondary amine of the general formula (I) ##STR00001##
in which R.sub.1 and R.sub.2 are each independently selected from C.sub.1-4-alkyl and C.sub.1-4-hydroxyalkyl; R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each independently selected from hydrogen, C.sub.1-4-alkyl and C.sub.1-4-hydroxyalkyl, with the proviso that at least one R.sub.4 and/or R.sub.5 radical on the carbon atom bonded directly to the nitrogen atom is C.sub.1-4-alkyl or C.sub.1-4-hydroxyalkyl when R.sub.3 is hydrogen; x and y are integers from 2 to 4 and z is an integer from 1 to 4; where the molar ratio of b) to a) is in the range from 0.05 to 1.0, and c) an acid in an amount, calculated as neutralization equivalent relative to the protonatable nitrogen atoms in a) and b), of 0.05 to 15.0%. One preferred amine of the formula I is 2-(2-tert-butylaminoethoxy)ethanol. The absorbent allows a defined H.sub.2S selectivity to be set at pressures of the kind typical in natural gas processing.

The method of obtaining methane clathrates consists in the fact that pure methane or methane in a gas mixture not containing hydrocarbons other than methane in amounts not exceeding 1% is contacted with a mixture of alkanes from C7 to C16 and most preferably light paraffin oil containing alkanes from C10 to C14, at a temperature of 5 to 20° C. and absolute pressure above 1 bar, until the solvent is fully saturated.

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.

Disclosed herein are scavenging compounds and compositions useful in applications relating to the production, transportation, storage, and separation of crude oil and natural gas. Also disclosed herein are methods of using the compounds and compositions as scavengers, particularly in applications relating to the production, transportation, storage, and separation of crude oil and natural gas.

The invention is directed to a process to prepare elemental sulphur by (i) contacting an aqueous solution comprising bisulphide with oxidised sulphide-oxidising bacteria under anaerobic conditions wherein elemental sulphur is produced and a reduced sulphide-oxidising bacteria is obtained and (ii) wherein the reduced sulphide-oxidising bacteria are oxidised by transfer of electrons to an anode of an electrochemical cell to obtain the oxidised sulphide-oxidising bacteria.