Regeneration method for gas treating apparatus

A method of desulphurizing a flue gas comprising the following steps which are each repeated in accordance with a predetermined time schedule:

• a. continuously introducing a pressurized flue gas containing a sulphur oxide into each of a plurality of adsorption beds, each bed being arranged in parallel with respect to a flow of said flue gas and being packed with a layer of activated carbon, the pressure of said flue gas always being exerted on the activated carbon layer;
• b. supplying a predetermined flow of a regenerating liquid on the top surface of said activated carbon layer in an adsorption bed to be regenerated in such a manner that substantially the whole area of said top surface of said activated carbon layer is sufficiently wetted by said regenerating liquid, whereby sulphuric acid formed from the sulphur oxide and water and adsorbed in said activated carbon is washed down to regenerate said activated carbon;
• and
• c. stopping the supply of said regenerating liquid after a predetermined period of time, whereby the flowing of said flue gas through said adsorption bed is allowed and drying of said activated carbon starts, the step of supplying of said regenerating liquid being carried out in such a manner that each of said supplying steps with respect to each of said adsorption beds does not superpose within said time schedule, the flow of gas through each of said adsorption beds being solely controlled by the supplying of regenerating liquid thereto.

A method of desulphurizing a flue gas comprising:

• a. introducing a flue gas containing a sulphur oxide and oxygen at a temperature of from about 55.degree. to about 150.degree.C through a passageway communicated with a flue source into a desulphuring apparatus wherein a plurality of adsorption beds, each being provided with an activated carbon layer, are arranged in parallel with respect to said passageway and a duct communicated with a chimney for exhausting the flue gas treated in said apparatus, each of said adsorption beds being in constant communication with said passageway and said duct;
• b. starting to supply a regenerating liquid at a predetermined flow rate to one of said adsorption beds after the quantity of sulphur oxide adsorbed in said activated carbon layer in said adsorption bed has reached a predetermined value;
• c. continuing to supply said regenerating liquid until the sulphuric acid formed from the adsorbed sulphur oxide is washed down sufficiently to regenerate said activated carbon layer;
• d. stopping the supply of said regenerating liquid into said one bed after said adsorption bed has been regenerated, whereby the flowing of said flue gas through said one adsorption bed automatically begins again so that the wetted activated carbon layer is dried and recovered to adsorb said sulphur oxide;
• and
• e. effecting the above steps of starting, continuing and stopping of said regenerating liquid into another adsorption bed so that the flow of flue gas through each bed is solely controlled by supply of regenerating liquid thereto.

A method for desulphurizing a hot flue gas containing sulphur oxide which comprises introducing the hot flue gas upwardly through a plurality of adsorption beds being arranged in parallel and containing activated carbon to remove the sulphur oxide;

• supplying a regenerating liquid selected from the group consisting of water and dilute sulfuric acid to the top of one of the adsorption beds when the concentration of adsorbed sulphur oxide has reached a predetermined level to remove the adsorbed sulphur oxide as the liquid passes downwardly through the bed;
• drying the wet activated carbon by passing the hot flue gas upwardly through the regenerated adsorption bed;
• controlling the rate of supply of said regenerating liquid to resist the passage of the flue gas upwardly through the bed during the regeneration step;
• when said bed is subsequently changed over from regeneration step to said drying step, stopping the supply of said regenerating liquid to remove the resistance of said liquid against the passage of said flue gas;
• and changing from the drying step to the adsorption step immediately after drying of the activated carbon is completed, the passage of the flue gas, concurrently supplied to each of said beds, through the one adsorption bed undergoing regeneration thereby being solely controlled by the supply of the regenerating liquid to said one bed.