Patent ID: 7767003

Claim:
A method of removing contaminants from a contaminated gas or vapour stream, which method includes passing a contaminated gas or vapour stream, which is at an elevated temperature and which contains a contaminant in condensable vaporized form and/or in the form of fine droplets entrained in the gas or vapour stream, through a bed of elongate spiral separating media linearly in an upward direction at a linear velocity of up to 6 m/s, the bed comprising a plurality of layers of the spiral separating media, with each layer comprising a plurality of the separating media located adjacent each other and with the separating media of one layer thus resting on the separating media of the layer below it; as the gas or vapour stream passes through the bed of separating media, allowing the contaminant in the contaminated gas or vapour stream to collect on the separating media of the first few rows of separating media by primary separation wherein the separating media remain wet due to condensation taking place in the separating media as well as drops that collect on the media and pass down from one separating medium to the separating medium below it, with the wet separating media assisting in capturing carbon and other solid particles present in the gas or vapour stream by causing them to adhere to the wet separating media in the first few rows and being washed down with the condensed liquid, and with the separating media towards the rear of the separating media bed remaining more-or-less dry thus ensuring effective secondary separation of residual contaminants still present in the gas or vapour stream after it has passed through the wet first few layers of separating media, thereby removing the contaminant from the gas or vapour stream and thus purifying the gas or vapour stream; allowing the contaminant that has collected on the separating media to pass from the separating media into a collection zone; removing the contaminant from the collection zone; and withdrawing a purified gas or vapour stream from the bed of separating media.