A number of industrial and other gases have noxious components which may be regarded as contaminants. Such gases are purified or separated from one or more noxious components by contact with solid sorption agents.
The solid sorption agents are single chemical compounds or admixtures of plural ingredients; they are generally employed in a finely-divided state to present the gas with a larger available contact surface. After sorption is effected, the noxious components removed from the gas are separated from the sorption agents, which can then be reused.
Appropriate sorption agents for the removal of recognized noxious components of such contaminated gases are known and available. They are employed in the form of a fixed filter bed (in an unmoved state) through which noxious-component-containing gas is passed or in the form of a fluidized bed.
Where input or contaminated gas is passed through a fixed filter bed, sorption ordinarily takes place extremely slowly, requiring extraordinarily voluminous filters and considerable energy to force the gas through such filters. When the gas is conducted through a fluidized bed, which consists of granular sorption material, the resulting purification effect is normally increased only slightly, and energy consumption is reduced only slightly; moreover, the granular sorption agent is abraided and the sorption agent must be renewed very often.
Known dry sorption methods for gas purification entail the disadvantage that, in spite of having systems capable of handling very large volumes of sorption agents, only comparatively small volumes of gas are purified and a reasonably-adequate purification is achieved only at gas temperatures below 600.degree. C. This also makes structural requirements and operation of very large plants extraordinarily expensive.