Abstract: Process for the production of hydrogen by reacting combustible substances with steam and converting carbon monoxide present in the resulting gaseous mixture into hydrogen and CO.sub.2 by reaction with steam. The amount of steam used in the conversion is increased by contacting said gaseous mixture before the conversion with a stream of water preheated by the gas obtained from the conversion reaction or by other sources of heat at low temperature, to achieve a saturation quench of said gaseous mixture by the conversion of the heated water with sensitive heat of the gaseous mixture into steam, and transfer of the heat from after to before the conversion. The saturated gaseous mixture is then heated to the temperature necessary for the conversion reaction.

Abstract: The removal of CO.sub.2 and mixtures thereof with H.sub.2 S from gaseous mixture containing same, is carried out by using an absorbing solution which comprises a first activating substance chosen from aminoacids and primary and secondary ethanolamines, which effects the initial absorption of CO.sub.2 with formation of a carbamate, a second activating substance chosen from As.sub.2 O.sub.3 and its derivatives, secondary ethanolamines and ammonia, which promotes the hydrolysis and decomposition of the carbamate as the latter forms, and a third substance of a basic nature, which effects the quantitative absorption of CO.sub.2 or CO.sub.2 +H.sub.2 S.

Abstract: The process for the purification of liquids and in particular the regeneration of spent absorbent solutions is essentially based on the use of a first preliminary regeneration zone to which the entire solution to be purified is delivered and the use of two terminal regeneration zones operating respectively at a higher and a lower pressure. The semi-regenerated solution issuing from the preliminary purification zone is split into two fractions which are delivered respectively to the low pressure and the high pressure terminal zones. The fraction delivered to the high pressure terminal zone is regenerated by steam yielded by means of the supply of external heat to the bottom of the zone. The fraction delivered to the low pressure terminal zone is regenerated by steam produced by heat recovered from the high pressure terminal zone.

Abstract: A process for removing gaseous impurities such as CO.sub.2 and/or H.sub.2 S from a gaseous mixture obtained by reacting combustible substances with steam, said steam being produced in boilers fed with water previously purified in degassing columns. The gaseous impurities are removed by means of an absorbent solution and the latter is regenerated in a regeneration column by stripping with steam. The stripping steam necessary for the degassing is delivered, at a pressure at least equal to that in the regeneration column, to the degassing columns and then to the regeneration column. The boiler feed water to be purified is previously heated, by supply of residual heats, to a temperature in the vicinity of the boiling temperature of the absorbent solution in the regeneration column.

Abstract: Improvements in the process for producing hydrogen in a plant comprising reforming units and shift conversion units. The residual heats obtained from the various units of the plant are used to heat an aqueous liquid to a temperature lower than the boiling temperature of water at the operating pressure of said units; the thus heated liquid is contacted with the process feeds to saturate the latter with steam; and the thus saturated process feeds are delivered to the reforming units. The quantity of steam supplied by the high pressure process boiler can be reduced accordingly.

Abstract: Process for removing gaseous impurities such as CO.sub.2, H.sub.2 S, HCN and SO.sub.2 from a gaseous mixture containing the same, comprising an absorption step in which the gaseous impurities are removed by a scrubbing solution, and a regeneration step in which the exhausted solution is submitted to stripping to remove the inpurities. The regenerated solution is treated with a flow of inert gases to improve the degree of regeneration and extract heat from said solution. The flow of inert gases, containing steam and desorbed impurities, is further enriched in steam supplied from the exterior and the resulting mixture is used as stripping means in the regeneration step.

Abstract: Improvements in the elimination and recovery of gaseous acid impurities from a gaseous mixture containing them, by an absorbing step, wherein said gaseous mixture is brought into contact with an alkaline absorbing solution and a regeneration step wherein the exhausted absorbing solution is regenerated by steam stripping, said absorption step comprising a main column and a secondary column, the main column operating at a higher pressure and by means of a supply of outside heat, the secondary column operating at a lower pressure and substantially by means of the steam obtained by expansion of the solution regenerated in the main column. The exhausted solution to be regenerated is conveyed firstly in one of the two regeneration columns wherein it is regenerated in an incomplete way, and subsequently into the other column where its regeneration is completed.

Abstract: A process for regenerating absorbent solutions used for removing gaseous impurities such as CO.sub.2, H.sub.2 S,HCN, SO.sub.2 and other acidic gases from gaseous mixtures by stripping with steam, which comprisesA. dividing the solution to be regenerated into a principal and a secondary fraction (p and s) and regenerating these fractions separately from each other in a principal and a secondary regeneration column (P and S), the principal regeneration column being operated at a pressure of at least about 0.2 to 0.5 atm above the pressure of the secondary regeneration column,B. regenerating the principal fraction in the principal regeneration column by heat which is fed from outside into the lower part of the column,C. regenerating the secondary fraction in the secondary regeneration column by heat which has been removed from the regenerated solution leaving the principal regeneration column andD. passing the regenerated fractions to the absorber.