Abstract: A catalyst filter comprising titania catalyst fiber and at least one layer of nonwoven fabric of polymer fiber, which can remove dust and nitrogen oxides from exhaust gas at the same time, has a high catalytic activity and maintains the high catalytic activity even after vibrating the filter to shake off calcium hydroxide and dust.

Abstract: A process for the systematic treatment of exhaust gases which comprises the steps of injecting a neutralizing absorbent and an auxiliary agent into the exhaust gas and passing the exhaust gas through a filter which has been precoated with the auxiliary agent, as used above, whereby the neutralizing absorbent and the auxiliary agent are permitted to deposit as a layer on the precoated filter and are able to collect the acidic gas components and dust in the exhaust gas and blowing ammonia into the emitted purified exhaust gas so that nitrogen oxides in the exhaust gas are reduced, in the presence of a denitrating catalyst, into nitrogen gas.

Abstract: The present invention is directed to a method for treating an exhaust gas which comprises cooling an alkaline neutralizing agent powder and blowing the cooled powder into the exhaust gas in order to remove acidic gaseous components from the exhaust gas, and recovering the used alkaline neutralizing agent, cooling it, and utilizing it again in order to remove acidic gaseous components from the exhaust gas.

Abstract: A filter medium for treating exhaust gases is described. The filter medium comprises a porous ceramic substrate, a pre-coat layer of a reaction aid and a layer of a solid material formed on one side of the substrate from which the exhaust gas is charged through the substrate, and a catalyst layer for eliminating nitrogen oxides formed on the other side of the substrate from which the exhaust gas is discharged. The filter medium may have a double-cylinder construction, in which the catalyst layer is formed on at least one side of a inner cylinder and the pre-coat layer and the solid material layer are formed on an outer side of an outer cylinder.