Abstract: Disclosed is an improved plate column suitable for use as a gas scrubber. This plate column comprises two or more sections and each section includes at least one preforated or grid plate without weir and downcomer and with a free-space ratio Fc of from 0.30 to 0.60 and includes a liquid feed distributor at the top portion thereof. The free-space ratio of the plate in each section increases from the uppermost section to the lowermost section. The liquid feed distributor except for the uppermost section is preferably provided with a number of nozzles in such a manner that liquid is sprayed within a central area of the plate which is about 10% to 50% of the total area of the plate.

Abstract: Disclosed is a wet process for efficiently and economically removing a specific gas component and/or solid component from a gas containing the same wherein the gas is countercurrently contacted with a scrubbing liquid in a perforated or grid plate column without weir and downcomer and having a free-space ratio of 0.30 to 0.60 under the conditions of a superficial gas velocity of from 1.5 to 8 m/sec and a liquid flow rate of from more than 110,000 to 250,000 kg/m.sup.2 .multidot. hr.

Abstract: Nitrogen oxides, or both sulfur oxides and nitrogen oxides are efficiently and economically removed from exhaust gas containing the same with an aqueous scrubbing suspension of alkaline earth metal compounds. The aqueous scrubbing suspension of alkaline earth metal compounds further contains (a) thiourea or thiosulfates or mixtures thereof and (b) copper ion or iron ion or a mixture thereof.

Abstract: Sulfur oxides and/or nitrogen oxides are removed from waste gas containing the same by adding chlorine dioxide or ozone gas to the waste gas in case where nitrogen monoxide is contained in the waste gas, and by scrubbing the waste gas with an aqueous scrubbing solution containing the sulfite of alkali metals or ammonium and oxidation retardant consisting of the sulfide, polysulfide or thiosulfate, of alkali metals or ammonium and thiourea.

Abstract: Nitrogen oxides can be efficiently removed from waste gas containing the same by oxidizing nitrogen monoxide into nitrogen dioxide, and then by scrubbing said waste gas with an aqueous scrubbing solution containing (a) a sulfur-containing reducing compound of alkali metals or ammonium such as alkali or ammonium sulfites, thiosulfates, sulfides, polysulfides and hydrosulfites and (b) a catalytic compound such as amino compounds, nitro compounds and oxidation or reduction derivatives thereof.

Abstract: A method and apparatus for disposal of rubber wastes is provided wherein rubber wastes such as scrap tires are dry-distilled in a vertical dry distillation retort of an internal heating type having a rotary discharge chute with a water seal, valuable substances contained in the rubber wastes, such as carbon black and oil, are effectively recovered and dry-distilled gas is used as a heat source for the dry distillation of the rubber wastes.

Abstract: A process for efficiently removing nitrogen oxides with a very high rate from waste gas is provided wherein nitrogen monoxide contained in the gas is oxidized by chlorine dioxide or ozone, and then the oxidized gas is brought into contact with sodium chlorite in water solution in an absorption column.

Abstract: A process for gas-absorption and dust-removal with an excellently high rate and capacity is provided wherein gas containing a specific gas component to be absorbed and/or fine dust to be removed is passed upwardly through a perforated plate or grid plate tower without weir and downcomer having a free-space ratio of 0.25 - 0.60, where said gas is contacted countercurrently with liquid absorbent under the stated conditions.