Abstract: Formation of calcium sulfite in a desulfurization column for desulfurizing flue gas is prevented by maintaining the pH of the sorption liquid in the column in the range of 5.5-7.0 and the chemical oxygen demand of the sorption liquid below an upper value determined by the concentration of magnesium sulfate. The upper value of the chemical oxygen demand of the sorption liquid can be controlled by maintaining the quantity of magnesium sulfate in an oxidization vessel arranged downstream of the desulfurization column. The oxidized liquid discharged from the oxidization vessel is neutralized in a double composition vessel, and the thus-obtained slurry is returned directly to the desulfurization column. By preventing formation of calcium sulfite, high-quality gypsum is formed in the double composition vessel.

Abstract: A method for desulfurization of an exhaust gas by a solution containing a Mg-based desulfurizing agent, followed by an oxidation step, a double decomposition step, a separation step of separating a slurry of a mixture of Mg(OH).sub.2 and gypsum dihydrate obtained in the double decomposition step, a step of returning a Mg(OH).sub.2 slurry separated in the separation step to the desulfurization step, a step of treating a gypsum dihydrate slurry in the oxidation step to convert accompanying Mg(OH).sub.2 into MgSO.sub.

Abstract: An apparatus for catalytic reaction containing a heating chamber having a hearth, side wall(s) and a roof, and an inlet and outlet for a heat source gas; a substantially vertically mounted concentric double cylindrical tubular reactor mounted in said roof and protruding into the space within said heating chamber; a gas-permeable dividing means which divides the space within the heating chamber into an upper convection heat transfer space and a lower radiant heat transfer space is useful in steam reforming and similar processes.

Abstract: A catalyst for steam reforming of a hydrocarbon carrying from three to twenty weight percent of nickel as nickel oxide, which is made by immersing alumina particles in a nickel containing solution, drying and then calcining the particles, which alumina particles are of a .alpha.-alumina and of 98 weight percent or more purity and has a pore volume of the pores having a diameter of from 0.1 to 0.5 microns of 0.2 ml/g or more and pore volume of the pores having a diameter of more than 0.5 microns but not more than 10 microns of 0.05 ml/g or more.

Abstract: A catalyst for steam reforming of a hydrocarbon or alcohol carrying from three to twenty weight percent of nickel as nickel oxide, which is made by immersing alumina particles in a nickel containing solution, drying and then calcining the particles, which alumina particles are of .alpha.-alumina and of 98 weight percent or more purity and has a pore volume of the pores having a diameter of from 0.1 to 0.5 micron of 0.2 ml/g or more and a pore volume of the pores having a diameter of 0.5 microns or more of 0.05 ml/g or more.

Abstract: A fuel cell power generating system comprising a central hydrogen-generating plant, a plurality of fuel cell power generating units installed respectively at the sites of power demand for on-site power generation, and piping comprising a main pipe connected to the hydrogen-generating plant, branch pipes connecting the fuel cell power generating units to the main pipe, and valves for regulating the pressure and flow rate of hydrogen gas according to the operating condition of the fuel cell power generating units. The fuel cell power generating units are operated according to power demand, and the surplus hydrogen gas is stored in the piping at an elevated pressure to supplement the capacity of the hydrogen-generating plant when the hydrogen gas demand of the fuel cell power generating units exceeds the capacity of the hydrogen-generating plant.

Abstract: The heat required for the steam reforming reaction is generated by flameless catalytic combustion. The heat thus-generated is passed to a steam reforming reactor zone by means of heat pipes.

Abstract: The heat required for the steam reforming reaction is generated by flameless catalytic combustion. The heat thus-generated is passed to a steam reforming reactor zone by means of heat pipes.

Abstract: An apparatus for carrying out a catalytic chemical reaction in the presence of a granular catalyst under conditions such that both the reactants and the reaction product are gaseous at the temperature and pressure of the reaction. According to the present invention, a vertically extending, annular, intercylinder space, defined between a cylindrical outer catalyst retainer and a cylinder inner catalyst retainer, is divided by radially extending vertical partition walls into a plurality of chambers. Heat-exchanging tubes are disposed vertically in at least one of the chambers. A granular catalyst is packed in at least two of said chambers to form at least two reaction chambers. A feed gas is caused to flow successively and in radial directions through these reaction chambers. Since the invention reactor achieves an improved linear gas flow velocity and a greater overall heat-transfer coefficient, the reactor of the invention requires fewer heat-exchanging tubes and can thus be made smaller.

Abstract: This invention provides an improved, simple and energy saving process for producing a gas containing methane, which process utilizes a reactor having a catalyst bed of a structure wherein a synthesis gas is allowed to pass perpendicularly to the longitudinal directions of a plurality of cooling tubes installed vertically within the catalyst bed. Within the cooling tubes, a liquid coolant at its boiling temperature is flowed upwardly under pressure. A portion of the reaction product gas leaving the catalyst bed is mixed, without cooling, with fresh feed gas and is recirculated to the catalyst bed. The amount of the recycled gas is less than 5 times the amount of fresh feed gas. The foregoing process produces a product gas containing methane from a feed gas containing carbon monoxide and hydrogen.

Abstract: Disclosed is a process for reforming hydrocarbon which comprises heating up to 800.degree. C. or higher a gaseous mixture of sulfur containing hydrocarbon with an oxidizing agent for reforming such as steam or a mixture of steam and carbon dioxide, while passing the gaseous mixture through an alkaline solid packing bed containing alkali metal and/or alkaline earth metal followed by bringing into contact thereof with a nickel containing catalyst at a temperature of 800.degree. C. or higher to produce a mixed gas containing hydrogen and carbon monoxide. An apparatus for the practice of the process is also disclosed.

Abstract: A vertical, cylindrical reaction vessel for catalytic, exothermic gas-phase reaction in which gaseous raw materials are passed substantially in the radial direction through a catalyst layer including therein cooling tubes extended vertically. A cooling medium is passed through the cooling tubes to remove the heat of reaction generated thereby attaining the optimum temperature distribution along the direction of flow of the gaseous raw materials.