An improvement in a wet scrubbing process for treating gaseous industrial process streams which contain one or more of SO.sub.2, SO.sub.3, H.sub.2SO.sub.4 which comprises contacting the stream of gas with a countercurrent flow of liquid derived from a circulating liquid stream which includes (i) a purge stream configured to remove a portion of the circulating liquid having a concentration of H.sub.2SO.sub.4 from the process, and (ii) a liquid make-up stream configured to replace the portion of the circulating liquid that is removed from the circulating liquid stream, the improvement comprising controlling the flow of liquid make-up whereby the concentration of H.sub.2SO.sub.4 in the purge stream is increased to a useful value; and filtering the purge stream to remove unwanted contaminants to yield a clarified purge stream.

An ammonia-containing tail gas absorption system, comprising at least two sets of absorption devices, wherein at least two transport pipelines are provided at inlets of some of the absorption devices, and the transport pipelines are used to communicate the absorption devices with an ammonia-containing tail gas outlet of a reactor or other absorption devices. Valves are provided on the transport pipelines, and the valves are used to control the connection and disconnection of the transport pipelines so as to switch the series-parallel relationship between the sets of absorption devices.

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.

Processes and systems for treating Kraft pulping foul condensate are provided. The processes comprise removing volatile compounds from the foul condensate to produce a resulting condensate and removing methanol from the resulting condensate. The systems comprise a volatile compound removal stage and a methanol removal stage downstream of and in fluid communication with the volatile removal stage.

This disclosure provides an integrated system and method for producing purified water, hydrogen, and oxygen from contaminated water. The contaminated water may be derived from regolith-based resources on the moon, Mars, near-Earth asteroids, or other destination in outer space. The integrated system and method utilize a cold trap to receive the contaminated water in a vapor phase and selectively freeze out water from one or more volatiles. A heat source increases temperature in the cold trap to vaporize the frozen contaminated water to produce a gas stream of water vapor and volatiles. A chemical scrubber may remove one or more volatiles. The integrated system and method utilize ionomer membrane technology to separate the water vapor from remaining volatiles. The water vapor is delivered for crew use or delivered to an electrolyzer to produce hydrogen and oxygen.

A liquid hydrocarbon desulfurization system having at least one processing unit, and preferably an initial and an end processing unit. Each processing unit having a reactor assembly and a sorption system. An aqueous system directs aqueous into the reactor assembly together with liquid hydrocarbon, wherein the two are mixed using shear mixers. An adsorbent system provides adsorbent to the sorption column to adsorb the oxidized sulfur resulting through the mixing of the liquid hydrocarbon with the aqueous. A system having multiple processing units is disclosed, as well as systems for transferring adsorbent and providing aqueous. A plurality of methods is likewise disclosed.

This disclosure provides an integrated system and method for producing purified water, hydrogen, and oxygen from contaminated water. The contaminated water may be derived from regolith-based resources on the moon, Mars, near-Earth asteroids, or other destination in outer space. The integrated system and method utilize a cold trap to receive the contaminated water in a vapor phase and selectively freeze out water from one or more volatiles. A heat source increases temperature in the cold trap to vaporize the frozen contaminated water to produce a gas stream of water vapor and volatiles. A chemical scrubber may remove one or more volatiles. The integrated system and method utilize ionomer membrane technology to separate the water vapor from remaining volatiles. The water vapor is delivered for crew use or delivered to an electrolyzer to produce hydrogen and oxygen.

A process and device for enhancing the chemical protection capability of a collective protection filter whereby the process stream exiting the collective protection filter is passed through an Auxiliary Filter. The auxiliary filter containing an ammonia removal media, such as zirconium hydroxide impregnated with zinc chloride (ZnCl.sub.2/Zr(OH).sub.4), an oxidizing media, preferably zirconium hydroxide impregnated with potassium permanganate (KMnO.sub.4/Zr(OH).sub.4), and a methyl bromide removal media, preferably activated carbon impregnated with triethylenediamine (TEDA/carbon). The auxiliary filter and process are configured to remove toxic industrial chemicals including NH.sub.3, NO.sub.x (mixtures of NO and NO.sub.2) and CH.sub.2O, and CH.sub.3Br.

Process and plant for the production of a urea ammonium sulfate granulate. In a first fluidized bed a first spraying liquid is sprayed comprising a urea melt and an aqueous solution of ammonium sulfate, e.g. a (near-) eutectic mixture. The bed temperature is below the crystallization temperature of the sprayed mixture. In a next compartment the granulate is fluidized to form a second fluidized bed. A second spraying liquid comprising a urea melt is sprayed into the second fluidized bed with a bed temperature higher than the bed temperature of the first fluidized bed and lower than the crystallization temperature of the sprayed second spraying liquid.

A liquid hydrocarbon desulfurization system having at least one processing unit, and preferably an initial and an end processing unit. Each processing unit having a reactor assembly and a sorption system. An aqueous system directs aqueous into the reactor assembly together with liquid hydrocarbon, wherein the two are mixed using shear mixers. An adsorbent system provides adsorbent to the sorption column to adsorb the oxidized sulfur resulting through the mixing of the liquid hydrocarbon with the aqueous. A system having multiple processing units is disclosed, as well as systems for transferring adsorbent and providing aqueous. A plurality of methods is likewise disclosed.