Abstract: A piping arrangement for two or three Claus catalytic converters and condenser sets used for recovering sulphur from gas streams containing hydrogen sulphide. One of the converters is operated at a sub-dewpoint temperature while the other(s) is(are) operated at a higher temperature for regenerating the catalyst. The piping arrangement includes two four-way switching valves that allow an influent gas stream to be switched between the two converters without leaving stagnant gas in the piping.

Abstract: In a process for the treatment of heavy oil, in which a hydrocarbon diluent is added to the heavy oil stream, part of the diluent is substituted by an LPG liquid stream. The LPG stream is added to the heavy oil stream after removal of light components including methane and carbon dioxide to reduce the vapor pressure of the stream, producing a sales oil stream.

Abstract: In a process for the treatment of heavy oil, in which a hydrocarbon diluent is added to the heavy oil stream, part of the diluent is substituted by an LPG liquid stream. The LPG stream is added to the heavy oil stream after removal of light components including methane and carbon dioxide to reduce the vapor pressure of the stream, producing a sales oil stream.

Abstract: A two position four-way switching valve has two inputs and two outputs. In one position of the valve, each input is connected to a defined one of the outputs, while in a second position the outputs are reversed. In a specific embodiment, the valve includes an inner cylindrical member enclosed within an outer casing having an opening forming an outlet. The other outlet and the two inlets are formed by tubes that extend inwardly through the casing and communicate with ports in the inner cylindrical member. The ports include first, second and third ports are spaced axially along the cylindrical member. Fluid entering through the inlets is routed to the outlets by plug-type valves including seals carried by an axially movable stem extending through the cylindrical member.

Abstract: An improvement in a process for the treatment of heavy oil in which a hydrocarbon diluent is subjected to distillation prior to its addition to a heavy oil production stream, to remove at least some of the light components in the diluent that would otherwise vaporize in the treatment process. A distillation unit for use in the process is also disclosed.