Abstract: [Problem] To provide a rotating classifier which can keep classification performance high and which can prevent blockages caused by biomass and the like. [Means for Resolution] The rotating classifier is characterized in that: comb teeth-like protrusion portions protruding toward a fixed member side are provided on top of rotary classification fins at intervals along the circumferential direction of the rotating classifier fins; a first gap is provided between an upper end portion of each of the comb teeth-like protrusion portions and a lower surface of the fixed member; a second gap formed between a protrusion portion and a protrusion portion adjacent to the protrusion portion is connected to the first gap; and an air stream flowing from the radial outside to the radial inside of the comb teeth-like protrusion portions through the first gap and the second gap is formed due to the rotation of the rotary classification fins.

Abstract: A desulfurization device releases exhaust gas into the atmosphere without reduction in CO2 recovery rate and without mercury components. Because the absorbent of the desulfurization device is drawn from an absorbent reservoir by a circulating pump and sprayed through spray nozzles into a desulfurization-absorption unit and is mainly circulated outside the wall of a water seal tube by a stirrer in the absorbent reservoir, the flow of the absorbent that falls from the desulfurization-absorption unit into the water seal tube flows in a single direction from top to bottom and hinders the ascension of gas bubbles. Intermixing of the gas for oxidizing the sulfur dioxide with the desulfurization device exhaust gas is thereby prevented, efficient CO2 recovery is possible without reduction in the CO2 concentration recovered from the exhaust gas after desulfurization and mercury in the combustion exhaust gas is absorbed in the absorbent of the desulfurization device.

Abstract: An object of the present invention is to provide an exhaust gas treatment system that effectively use heat recovered from an exhaust gas without any limitation in a CO2 chemical absorption equipment that requires enormous heat energy, and thus enabling reduction in running cost of the CO2 chemical absorption equipment.

Abstract: A wet type flue-gas desulfurization apparatus, into which exhaust gas containing mercury goes, includes an upstream absorption tower, an upstream absorbent spray nozzle and a make-up water supply unit on an upstream side of a desulfurization apparatus body in a flow direction of the gas. The upstream absorption tower has a circulation tank reserving absorbent slurry. The make-up water supply unit supplies make-up water into the circulation tank to keep the chloride ion concentration of the absorbent in the circulation tank not lower than 50,000 ppm. Thus, it is possible to provide a wet type flue-gas desulfurization apparatus by which Hg can be prevented from being released again from the desulfurization apparatus, the purity of recovered gypsum can be increased and the usage of industrial water can be reduced.

Abstract: A method for removing mercury in a combustion exhaust gas includes injecting ammonia or urea as a reducing agent into a combustion exhaust gas containing nitrogen oxides, sulfur dioxide, metallic mercury, and hydrogen halides, and then introducing the combustion exhaust gas to a denitration apparatus filled with a denitration catalyst to cause a denitration reaction and oxidize the metallic mercury to produce mercury halide; and introducing the combustion exhaust gas through an air preheater and an electric dust collector to a wet desulfurization apparatus, thereby removing sulfur dioxides and the mercury halide, wherein the ammonia concentration of the combustion exhaust gas at an exit of the denitration apparatus is maintained at 5 ppm or higher, and the mercury halide is adsorbed or precipitated onto combustion ash and collected by the electric dust collector to discharge the mercury halide out of a system.

Abstract: A wet flue gas desulfurization device includes, an absorber provided with: a absorber tank provided at a lower part of the absorber so as to store an absorption liquid; an absorption portion provided above the absorber tank and having multiple stages of spray headers for spraying the absorption liquid; an absorption liquid circulation system for circulating the absorption liquid in the absorber tank to the spray headers; an exhaust gas inlet portion provided in a sidewall between the absorber tank and the absorption portion; and a gas blow-out prevention member provided along an entire circumference of an inner surface of the sidewall between the exhaust gas inlet portion and the uppermost-stage spray header. Dams are intermittently provided at an inner peripheral end of the gas blow-out prevention member to extend along a circumferential direction thereof.

Abstract: Provided are a catalyst for removing mercury metal, which has high activity for a long time even in an exhaust gas containing SO2, and a method for oxidizing mercury metal using the catalyst. A method for purifying exhaust gas, including bringing an exhaust gas containing mercury metal into contact with a catalyst containing titanium oxide as a first component and a sulfate or phosphate of nickel (Ni), manganese (Mn) or vanadium as a second component, at a temperature of from 100° C. to 200° C., and thereby oxidizing the mercury metal.

Abstract: After adjusting an exhaust gas temperature at an exit of a heat recovery unit (11) of an exhaust gas treating apparatus to not more than a dew point temperature of sulfur trioxide (SO3), a heavy metal adsorbent is supplied from a heavy metal adsorbent supply unit (16) disposed in an exhaust gas at an entrance of a precipitator (4) or an intermediate position within the precipitator (4), and the exhaust gas containing the heavy metal adsorbent is supplied into the precipitator (4). Preferably at this stage, the heavy metal adsorbent is supplied into the exhaust gas at the entrance of the precipitator (4) 0.1 seconds after the exhaust gas temperature at the exit of the heat recovery unit (11) has been adjusted to not more than the dew point temperature of SO3.

Abstract: In an exhaust gas treatment device provided with: an exhaust gas treatment unit in which an oxygen combustion boiler 1 using coal as fuel, a denitration device 3, an air preheater 4, a dust-collection device 5, a desulfurization device 6, and a carbon dioxide recovery device 8 are sequentially arranged from the upstream side to the downstream side of an exhaust gas duct; and an exhaust gas circulation unit which branches off from the exhaust gas duct at an outlet of the dust-collection device 5 or an outlet of the desulfurization device 6 and through which the exhaust gas is preheated by the air preheater 4 and returned to the oxygen combustion boiler 1, a heat-recovery heat exchanger 13 that adjusts a gas temperature at an inlet of the dust-collection device 5 to be not greater than an acid dew point of SO3 and not lower than a water dew point is provided between the air preheater 4 and the dust-collection device 5, a reheating heat exchanger 13 that adjusts a gas temperature to be not lower than the acid de

Abstract: With an installation construction method for boiler facilities, the boiler facilities comprise a boiler building configured of a steel structure, and a boiler main unit suspended within the boiler building from the upper portion of the boiler building. A portion of the boiler building is constructed, a portion of the boiler main unit is suspended from the upper portion of the partially-constructed boiler building, and while the remaining steel structure portions are being added to the partially-constructed boiler building so as to construct the boiler building, the remaining portions of the boiler main unit are added to complete the boiler main unit.

Abstract: An apparatus for removing of traces of toxic substances from exhaust gas, comprising, disposed in sequence from the upstream side in a flow channel of exhaust gas emitted from combustion equipment, a denitration unit including a denitration catalyst layer capable of removing nitrogen oxides from the exhaust gas and capable of oxidizing metallic mercury; an air preheater adapted for heat exchange between air for combustion in the combustion equipment and the exhaust gas; a dust removal unit having a bag filter containing a catalyst for metallic mercury oxidation; and a desulfurization unit for removing sulfur oxide from the exhaust gas. The bag filter may be disposed in advance of the desulfurization unit. Thus, there can be provided an apparatus for removing of traces of toxic substances from exhaust gas that is stable over a prolonged period of time and is highly reliable; and provided a method of operating the same.

Abstract: An absorbing tower is provided in its side wall with a gas entrance for introducing a combustion exhaust gas into the absorbing tower, and an absorbing liquid is sprayed from the nozzles of a spray header into the exhaust gas introduced to rise from the gas entrance. A trough is arranged in the side wall of the absorbing tower and above the gas entrance, and a nose having a horseshoe shape in a top plan view and extending into tower is disposed in the tower side wall portion of the gas entrance other than the portion arranging the trough and at the same or at substantially the same height as the portion of the trough. The absorbing liquid, which is sprayed from the nozzle and drops along the absorbing tower wall portion, is rescattered to the center portion of the absorbing tower excepting the entrance of the absorbing tower, so that the gas-liquid contact efficiency is improved while suppressing an increase in pressure loss, thereby to prevent the drift of the gas at the tower wall portion.

Abstract: A system is provided that prevents inhibition of adsorption of Hg and other heavy metals by activated carbon or other heavy metal adsorbent due to prior adsorption of sulfur trioxide (SO3) in an exhaust gas containing SO3. As it has been found that while SO3 is adsorbed, the adsorption of SO3 precedes the adsorption of Hg and other heavy metals onto activated carbon, a basic substance injection system is disposed along an exhaust gas flow channel at an upstream side of an activated carbon injection system, thereby attaining effective removal of Hg and other heavy metals from the exhaust gas by adsorption thereof onto surface pores of the activated carbon. The SO3 concentration after removal by basic substance conversion is computed from the SO3 concentration before removal, and the activated carbon injection rate can be controlled based on the concentration after removal.

Abstract: An absorbing tower provided with plural spray headers (3) which each have a plurality of spray nozzles (5) and are arranged in a multi-stage state in the flow direction of exhaust gas, in which an absorption liquid containing a slurry of limestone or lime is sprayed through the nozzles (5) to absorb and remove sulfur oxide contained in exhaust gas, wherein each spray nozzle (5) is of an annular spray type (a hollow cone type) and the spray nozzles (5) in the neighborhood of the tower wall have such a structure that the fluid is sprayed radially at spray angles of 50 to 80° with the direction counter to the flow of exhaust gas as the center, while the nozzles (5) in the central part of the tower have such a structure that the fluid is sprayed radially at spray angles of 80 to 130° with the direction counter to the flow thereof as the center.

Abstract: A pulverized coal burning boiler is provided, which reduces an air-excess ratio thereby to reduce the emission of unburned contents such as CO. The pulverized coal burning boiler includes a pulverized coal feed measuring device for measuring the feeding rates of the pulverized coal to be conveyed through coal feeding pipes, individually, and a control device for calculating the burning air feeding rates to match the pulverized coal feeding rates thereby to send a control command signal to burning air feed adjusting device, so that a burner air ratio set by a burner air ratio setting device may be kept on the basis of both the pulverized coal feeding rate, which is measured by the pulverized coal feed measuring device, and the burning air feeding rate, which is measured by the burning air feeding rate measuring device and fed to a pulverized coal burner connected to the coal feeding pipes.

Abstract: Absorption liquid recirculating pipes fitted with absorption tower (absorber) recirculating pumps corresponding to individual spray headers are inserted from the void tower portion inside absorption tower, near the liquid surface of liquid trapping portion (recirculation tank), in the interior of the absorption tower, erected vertically from substantially the center of the absorption tower and connected to respective spray headers provided in multiple stages along the direction of gas flow. Multiple nozzles of each of the spray headers are disposed mutually concentrically or rectangularly on a plane orthogonal to the direction of flue gas flow within the absorption tower.

Abstract: A spraying material for coating a metallic member, being inexpensive and having superior corrosion and erosion resistance even in high temperature environments, wherein the material is composed of an Fe—Si based compound and comprises an alloy composed of 10 to 35% by weight of Si and the remainder of Fe and inevitable impurities, and further, up to 5% by weight of B may be added to the material in terms of improvement in hardness and adhesiveness of the coating is provided in order to protect components such as heaters and water walls of coal fired boilers and heat exchanger tubes of fluidized bed boilers, etc., from corrosion and erosion. The spraying material is formed into a coating by, for example, high velocity flame spraying or atmospheric plasma spraying.

Abstract: An installation construction method is provided for boiler facilities in which the boiler facilities include a boiler building configured of a steel structure, a boiler main unit to be installed within the boiler building, various types of equipment to be installed to the boiler main unit, and accessory members which are accessory thereto. During construction of the boiler building, the various types of equipment and the accessory members are carried into the boiler building and installed.

Abstract: An exhaust gas denitrizer removes nitrogen oxides from rejoined exhaust gas using a denitrification reactor after supplying ammonia gas to the rejoined exhaust gas made up of main exhaust gas cooled by a fuel economizer by flowing through a main duct and bypass exhaust gas maintained at high temperature by flowing through a bypass duct adapted to bypass the fuel economizer. At a meeting place between the main exhaust gas and bypass exhaust gas in the main duct, three partition plates are installed with plate surfaces turned to an inflow direction of the bypass exhaust gas, partitioning a main exhaust gas channel into a plurality of subchannels. Upstream-side ends of the partition plates face the incoming bypass exhaust gas by being shifted from one another toward an upstream side of the main exhaust gas starting from an inflow side of the bypass exhaust gas.

Abstract: A boiler apparatus for leading fluid from a plurality of upper walls (2) to (4) to a ceiling wall (7) through a ceiling wall inlet header (11), characterized in that a ceiling wall inlet mixing header (8) is installed between the plurality of upper walls (2) to (4) and the ceiling wall inlet header (11).