Abstract: A device to eliminate particulates contained in exhaust gas ejected from motors, such as diesel engines for ships, surface transportation vehicles and overland fixed diesel engines, and a process to eliminate particulates contained in the exhaust gas are provided.

Abstract: CaS oxidation has CaS particles oxidized into CaSO4 completely as far as to the interior of the particle. The interior of an oxidation apparatus 1 is partially partitioned by a partition 22 to thereby form a first fluidized bed 20 on the inner side, a second fluidized bed 21 on the outer side and a space portion 23 thereabove. A heat exchanger 27 having a baffle plate is disposed on the inner side of the partition 22 and an in-bed heat exchanger 33 is disposed on the outer side of same. A desulfurizing product-containing fine powder 204 and coarse powder 205 and a mixture gas 206 of nitrogen, oxygen and steam are supplied into the second fluidized bed 21. Also, coal 200 and coal char 201 are supplied into the first fluidized bed 20 from below.

Abstract: A dust collecting apparatus and method for dedusting a Ca-containing gas using a ceramics filter is provided, in which a filter differential pressure elevation rate is suppressed. A desulferizing agent 103 and a mineral 106 containing MgO are supplied via a hopper 13, 15 a valve 14 and a feeder 16 into a pressurized fluidized-bed combustion furnace 1 together with coal 101 and air 102. A combustion gas 201 is dedusted by a cyclone 2 to become a combustion gas 301, the combustion gas 301 enters a filter container 3a, 3b having a ceramics filter 31a, 31b and is further dedusted. A combustion gas 401 which is dedusted is supplied into a gas turbine 4 to generate power, and combustion gas 501 heats a waste heat recovery boiler 5 which in turn drives a steam turbine 7. The mineral 106 containing MgO is added in the combustion gas 301 which flows in the ceramics filter 31a, 31b. Thereby MgO is added to the combustion gas so that the filter differential pressure elevation rate can be suppressed.

Abstract: This invention relates to a technique for removing nitrogen oxides (NO.sub.x) present in exhaust gases discharged from boilers and the like. When the temperature of the exhaust gas is 100.degree. C. or below, a heat-treated active carbon produced by heat-treating a raw active carbon at 600 to 1,200.degree. C. in a non-oxidizing atmosphere so as to remove oxygen-containing functional groups present at the surfaces thereof and thereby reduce the atomic surface oxygen/surface carbon ratio to 0.05 or less is preferably used. When the temperature of the exhaust gas exceeds 100.degree. C., a heat-treated active carbon produced by heat-treating a raw active carbon at 600 to 1,200.degree. C. in a non-oxidizing atmosphere and activating the surfaces thereof with sulfuric acid or nitric acid to impart oxidizing oxygen-containing functional groups thereto is preferably used.

Abstract: An active carbon for use in the treatment of exhaust gas can be obtained by heat-treating a starting active carbon fiber derived from polyacrylonitrile, pitch or the like or a starting particulate active carbon in a non-oxidizing atmosphere. The heat-treating temperature is preferably in the range of 600 to 1,200.degree. C. for use in the desulfurization of exhaust gas, and in range of 600 to 1,000.degree. C. for use in the denitration of exhaust gas. By using the resulting heat-treated active carbon for the purpose of desulfurization, the sulfur oxide concentration in exhaust gas can be reduced to 5 ppm or below. Moreover, by using the heat-treated active carbon in combination with conventional denitration based on selective catalytic reduction, the nitrogen oxide concentration in exhaust gas can be reduced to 1 ppm or below.