Recovery of shield gases used in welding and other processes

摘要

Plant for the recovery of shield gas used in welding or metal cutting operations into which the gas/air mixture is drawn and passed through an adsorber that separates the components. The adsorber is layered so that the gases pass, from the bottom, through a drying layer, a zeolite layer and an activated carbon layer or a molecular carbon sieve. A control unit regulates the process parameters. Gases are drawn from the working environment by a pump and passed through a filter, to remove dust and metallic particles, into a storage vessel. From here gas is passed into one, or more, adsorbers in series, or in parallel. The recovered shield gas is then stored in another vessel. Where more than two adsorbers, connected in series, are used, a duplicate shield gas storage vessel is placed after two of the adsorbers. The adsorbers are regenerated by the use of a vacuum pump and throttle valves, which regulate the flow rates.