Imperial Chemical Industries Limited

Edwin Stephen Willis

Peter J Carnell

Gavin Paul Towler

Peter John Herbert Carnell

Hiren Krishnakant Shethna

A process for the purification of a fluid stream containing a sulphur contaminant, such as hydrogen sulphide, and mercury, phosphine, stibine, and/or arsenic compounds as a second contaminant wherein said fluid stream is passed through a bed of a particulate absorbent containing a sulphide of a variable valency metal, especially copper, that is more electropositive than mercury, to remove said second contaminant and then the sulphur contaminant is removed from at least part of the effluent from that bed by passing that part of the effluent through a bed of a particulate sulphur absorbent comprising a compound selected from oxides, hydroxides, carbonates and basic carbonates of said variable valency metal is disclosed. The removal of the sulphur contaminant converts said variable valency metal compound to the corresponding sulphide. The resulting bed of variable valency metal sulphide is subsequently used for the removal of the second contaminant.

Process for removal of sulphur together with other contaminants from fluids

A double-loop process for the removal of specified gas or gases from a process gas by absorption with a liquid absorbent for said specified gas or gases wherein the process gas is contacted counter-currently in a first absorption stage with semi-lean absorbent liquid and then in a second absorption stage with lean absorbent liquid to give a sweet process gas and the absorbed gases are stripped from the laden absorbent liquid in a first stage giving a semi-lean absorbent liquid. Part of the semi-lean absorbent is recycled to the first absorption stage while the remainder is subjected to further stripping by counter-current contact with an auxiliary gas that has a concentration of the specified gas or gases that is lower than the concentration of the specified gas or gases in the process gas to give the lean absorbent liquid which is recycled to the second absorption stage. The auxiliary gas, which is especially a part stream of the sweet process gas, may be recycled, after use for stripping, to the process gas upstream of the first absorption stage. The process may be integrated with a glycol drying stage with regeneration of the wet glycol by stripping with the part stream of the sweet process gas before the latter is used for stripping the semi-lean absorbent liquid.

Gas absorption

Removal of sulphur together with other contaminants from fluids

Purification process

Growing community of inventors

Northallerton, United Kingdom

Edwin Stephen Willis