Abstract: A combustion apparatus including a mixture feeding pipe for injecting a mixture of pulverized coal for combustion air into a furnace, with the mixture being then ignited. A first gas feeding passage is disposed outwardly of the mixture feeding pipe for feeding oxygen-containing gas into the furnace, with a second gas feeding passage being disposed between the gas feeding passage and the mixture feeding pipe, in a radial direction, for feeding the oxygen-containing gas into the furnace. A projection is disposed between the gas feeding passage and the mixture feeding pipe and extends at an exposed end surface thereof into the furnace beyond an exposed end of the mixture feeding pipe, with the projection being hollow for allowing the oxygen-containing gas to flow within the projection.

Abstract: An apparatus for wet process exhaust gas desulfurization including a spraying portion for spreading absorbent slurry including calcium compound, an absorbing tower for bringing the absorbent slurry sprayed from the spraying portion into contact with exhaust gas including sulfur oxides from opposite directions so as to absorb the sulfur oxides in the exhaust gas into the absorbent slurry, a slurry tank disposed below the absorbing tower for receiving the absorbent slurry from the absorbing tower, a plurality of stirrers for stirring each stirrer being an axial flow type agitator having a propeller, and circular system for circulating the absorbent slurry from the slurry tank to the spraying portion. The apparatus further includes a plurality of nozzles for feeding oxidizer gas including oxygen into the absorbent slurry from a backside of each propeller towards a periphery thereof uniformly with respect to a circumferential direction, thereby bubbling the oxidizer gas finely around each propeller.

Abstract: A catalyst for purifying an exhaust gas includes a first component having activity for reducing nitrogen oxides with ammonia and a second component having at least one of activity for forming nitrogen oxide from ammonia and activity for forming carbon dioxide from carbon monoxide. The first component is a composition containing an oxide of at least one member selected from titanium, vanadium, tungsten and molybdenum and the second component is a composition containing a salt of a noble metal selected from platinum, palladium and rhodium or any one of these noble metals supported on a porous material selected from zeolites, alumina and silica. The invention further provides a method for purifying an exhaust gas containing NOx, CO and leak NH.sub.3 using the catalyst.

Abstract: NOx removal catalyst can be obtained by kneading various kinds of inorganic fibers and water containing a surfactant to make a pulp-like substance, adding a catalytic component thereto and then further kneading the resultant mixture to prepare a catalyst paste. The thus obtained catalyst paste is shaped into a honeycomb-like, plate-like or column-like form according conventional various molding methods, and then dried and calcined for use. Instead of the above catalytic components; catalytic carriers such as titanium, zeolite, zirconia and the like may be shaped and calcined in the same manner and used for carrying a catalytic component. A particularly high performance and strength can be obtained with good result when a composition produced by calcining a molybdenum (Mo), vanadium (V) or tungsten (W) compound born on titanium oxide at 400.degree. to 700.degree. C. is used.

Abstract: A process for producing a denitration catalyst comprising the following steps of immersing a base material composed of an inorganic fiber cloth in an aqueous slurry containing 5 to 20% by weight of at least one sol-form substance selected from the group consisting of silica sol, titania sol and zirconia sol, as a first component, 20 to 70% by weight of at least one inorganic oxide fine powder selected from the group consisting of those of titania, zirconia and cordierite, as a second component, and 1 to 3% by weight of at least one organic binder selected from the group consisting of polyvinyl alcohol, polyvinyl acetate and carboxymethyl cellulose, as a third component, removing superfluous liquid from the resulting base material, drying the base material, coating catalyst components onto the surface of the dried base material, and drying and calcining the resulting material, are proposed.

Abstract: A part of an ICM housing including a portion to be repaired, welded to a wall of a reactor pressure vessel in operation, is cut and removed and a new ICM housing half is welded to the remaining part of the ICM housing to form a new ICM housing. The new ICM housing is provided at the welding portion thereof with a molten metal layer containing 4 wt % or more .delta. ferrite. A sleeve made of stainless steel is located at the welding portion of an inner peripheral surface of the new ICM housing made so as to be molten by a TIG welding machine to form the molten metal layer, with the molten metal layer preventing stress corrosion cracking of the new ICM housing.

Abstract: A combustion apparatus including a mixture feeding pipe for injecting a mixture of pulverized coal and combustion air into a furnace, with the mixture then being ignited. A radially outwardly flared flame maintaining ring is provided at a tip end of the mixture feeding pipe, with the maintaining ring being exposed to a reduced atmosphere and to high temperatures due to radiant heat from the furnace. A projection extends into the furnace beyond the flame maintaining ring so as to protect the flame maintaining ring from radiation from inside the furnace thereby suppressing an excessive increase in temperature. Combustion air flows along a surface of the projection so as to provide at oxidized atmosphere.

Abstract: A pressurized fluidized-bed boiler power plant comprises: a pressurized fluidized-bed boiler including a fluidized-bed boiler and a pressure vessel containing the fluidized bed; a single-shaft gas turbine including a gas turbine, an air compressor and an electric generator; and a steam turbine unit in which steam generated by the pressurized fluidized-bed boiler drives a turbine so that electricity is generated. In the power plant, an air cooler is situated on a duct for conveying the compressed air from the compressor to the boiler or at an inlet of the compressor. Alternatively, there may be provided a device for conveying the compressed air from the compressor by way of the air cooler to a space formed by the fluidized-bed boiler and the pressure vessel of the pressurized fluidized-bed boiler. During operation, the compressed air is cooled to a temperature level allowable for the pressure vessel before it is supplied to the boiler.

Abstract: A burner for pulverized coal has a coal duct for pulverized coal and primary combustion air and a secondary combustion air duct such that the coal and primary air and secondary air mix outside the outlet nozzles of the duct in a mixing zone at which combustion occurs. Coal distribution means in the coal duct create, adjacent the outlet nozzle, at least one outer zone of flow spaced from the coal duct axis and at least one inner zone of flow nearer the coal duct axis. These are means for slowing flow in the outer zone relative to the flow in the inner zone, prior to the mixing zone. To achieve good mixing, and promote NO.sub.x reduction, the coal concentration in the outer zone is higher than in the inner zone. The slowing means may be radially inwardly projecting baffles.

Abstract: An ICM housing welded to a wall of a reactor pressure vessel in operation is provided with a molten metal layer containing 4 wt. % or more .delta. ferrite at a portion of an inner peripheral surface thereof which corresponds to a weld. A sleeve made of stainless steel is located at the competent portion of the inner peripheral surface of the ICM housing stainless steel so as to be molten by means of a TIG welding machine to form the molten metal layer. The molten metal layer prevents stress corrosion cracking of the ICM housing.

Abstract: A pyrolysis furnace for cracking hydrocarbons comprising a furnace; a pair of inlet tubes extending generally vertically within the furnace and connected to an outlet tube having a larger diameter than either of the inlet tubes and extending generally vertically within the furnace to an outlet; and burners for imparting radiant heat adjacent to the inlet tubes and adjacent to the outlet tube. The inlet tubes and the outlet tube define a single pass configuration through the furnace.

Abstract: A process for producing a denitration catalyst suitable for catalytically reducing nitrogen oxides in exhaust gases having a low dust content with ammonia is provided, which process comprises adding water to catalyst raw materials affording titanium oxide, molybdenum oxide and vanadium oxide at the time of calcination respective proportions thereof being in the range of Ti/Mo/V=97-65/3-20/0-15 atomic %, to make slurry, followed by coating the slurry onto a metal substrate and drying. Molybdenum oxide particles are coated on a titanium oxide particle at calcination, which makes the grindability of the catalyst particle easy and improve its adherence to the metal substrate.

Abstract: A catalyst for reducing nitrogen oxides in the exhaust gas with ammonia, having a catalyst composition coated on an inorganic fiber cloth as a substrate is provided. The inorganic fiber cloth is impregnated with at least one inorganic oxide selected from silica and said catalyst composition, preferably with an organic binder like polyvinyl alcohol, so that the weight ratio of the inorganic oxide/said inorganic fiber cloth is in the range of 0.05 to 0.8 and the inorganic oxide is substantially placed between the fibers constituting said inorganic fiber cloth.The above inorganic fiber cloth is preferably a glass fiber cloth, more preferably a glass fiber cloth which surface is acid-treated to have a layer deficient in alumina and calcium oxide.

Abstract: A coal combustion apparatus having prevented deterioration of a denitration catalyst due to volatile metal compounds contained in exhaust gases is provided, which apparatus comprises a combustion furnace, a denitration means for removing nitrogen oxides in an exhaust gas from the furnace by reducing nitrogen oxide with ammonia, a means for collecting ashes in the gas having left the denitration means and a means for recycling the collected ashes into the furnace, and is characterized in providing an oxygen concentration meter in the flow path of the gas between the furnace and the denitration means and also providing an oxygen concentration-controlling means relative to air fed inside the flow path of the gas from the furnace to the denitration means so as to control the oxygen concentration detected by the oxygen concentration meter to a definite value or higher.

Abstract: A high temperature reactor has a downflow type nuclear reactor provided at the top portion thereof with a gas inlet and a plurality of steam generators provided around the nuclear reactor. The steam generator has a heat insulation tube provided vertically from the bottom portion of the nuclear reactor to a level higher than the top gas inlet of the reactor, a heat exchanger provided in a descending gas flow path formed around the heat insulation tube, and a gas circulator provided at the bottom portion thereof for feeding a gas coolant to the gas inlet of the nuclear reactor, whereby said gas coolant, after being used for cooling the reactor core, delivered from the bottom portion of the reactor, flows into the heat insulation tube, flows upward to the top portion of the tube, is reversed in direction at the top end of the tube, then flows downward through the descending gas flow where the heat exchanger is provided, and is then recycled to the gas inlet flow path of the reactor by the gas circulator.

Abstract: A process for producing carbamic acid esters (N-phenyl carbamate) which comprises reacting an amino group-containing compound (aniline), oxygen, a nitro group-containing compound (nitrobenzene), a carbon monoxide-containing gas and a hydroxyl group-containing organic compound (ethyl alcohol) in the presence of a compound of a transition metal belonging to Pt group of VIII group (Pd) of the Periodic Table as catalyst, a non-metal halide (HCl) and water.

Abstract: A burner apparatus for pulverized coal comprises a pulverized coal supply pipe, a starter oil burner extending within the pulverized coal supply pipe to define therebetween a tubular passage through which a mixture of combustion air and pulverized coal passes into a furnace, a flame holder provided at an outer periphery of one end of the pulverizerd coal supply pipe facing to the furnace, a cylindrical member disposed in the tubular passage for dividing a part thereof into two coaxial passage parts, and a valve adapted to close an axial end opening of the cylindrical member for varying a concentration of pulverized coal in a radial outer passage part of the coaxial passage parts.

Abstract: A catalyst for denitration by catalytic reduction using ammonia capable of preventing catalyst deterioation due to vapors of heavy metal compounds contained in exhaust gases and having a high strength and a superior resistance to poisons and a process for producing the catalyst are provided, which catalyst comprises TiO.sub.2, oxide(s) of at least one of V, Cu, Fe and Mn and oxide(s) of at least one of Mo, W and Sn, the total of the mol number(s) of the oxide(s) of at least one of Mo, W and Sn falling within a range of 2.times.10.sup.-6 to 20.times.10.sup.-6 mol/m.sup.2 per the unit specific surface of the catalyst, and which process comprises having oxide(s) of at least one of Mo, W and Sn adsorbed and supported onto a composition comprising TiO.sub.2 prepared in advance and oxide(s) of at least one of V, Fe, Cu and Mn so as to give the above-specified total of the mol number(s) of oxide(s) of at least one of Mo, W and Sn.

Abstract: A catalyst or a catalyst structure for removing nitrogen oxides contained in exhaust gases, having a small pressure loss and hard to cause ash deposition, and a process for producing the same are provided, which catalyst comprises a mixture of a catalyst composition of titanium oxide and at least one member of oxides of vanadium, molybdenum and tungsten, and inorganic fibers, the clearances of the inorganic fibers are filled with said catalyst composition; the ration by weight of said catalyst composition to said inorganic fibers is 3 or more; and the apparent density of said catalyst is 0.8 g/cm.sup.3 or more; and which process comprises providing a composition containing titanium oxide and at least one member of oxides of vanadium, molybdenum and tungsten, calcining said composition at 500.degree.-650.degree. C., crushing the calcined material so that powder of 20.mu.

Abstract: An exhaust gas-purifying catalyst capable of carrying out the CO-oxidizing reaction and the reduction reaction of NO.sub.x with NH.sub.3 in the same reactor and with good efficiency, and a process for purifying exhaust gases using the catalyst are provided, which catalyst comprises Cu and/or Co supported by Zr oxide or Ti oxide mixed with a Cu-substituted type zeolite.