Abstract: The problem addressed by the invention lies in providing a method for producing an inorganic substance powder highly-oriented thin film sheet with which it is possible to produce a sheet of uniform thickness while preventing the generation of impurities, improving sheet surface properties, adjusting apparent specific gravity, and the like. The method for producing a thin film sheet comprises a step for preparing a predetermined inorganic substance powder, thermoplastic resin, and auxiliary agent, a step for exposing the starting materials mixed at a predetermined mixture ratio to high shear stress while kneading, a step for feeding the kneaded starting materials to a T die-type extrusion molding device and molding a sheet, and a step for adjusting the apparent gravity as desired by stretching under predetermined conditions.

Abstract: The problem addressed by the invention lies in providing a method for producing an inorganic substance powder highly-oriented thin film sheet with which it is possible to produce a sheet of uniform thickness while preventing the generation of impurities, improving sheet surface properties, adjusting apparent specific gravity, and the like. The method for producing a thin film sheet comprises a step for preparing a predetermined inorganic substance powder, thermoplastic resin, and auxiliary agent, a step for exposing the starting materials mixed at a predetermined mixture ratio to high shear stress while kneading, a step for feeding the kneaded starting materials to a T die-type extrusion molding device and molding a sheet, and a step for adjusting the apparent gravity as desired by stretching under predetermined conditions.

Abstract: The problem addressed by the invention lies in providing a method for producing an inorganic substance powder highly-oriented thin film sheet with which it is possible to produce a sheet of uniform thickness while preventing the generation of impurities, improving sheet surface properties, adjusting apparent specific gravity, and the like. The method for producing a thin film sheet comprises a step for preparing a predetermined inorganic substance powder, thermoplastic resin, and auxiliary agent, a step for exposing the starting materials mixed at a predetermined mixture ratio to high shear stress while kneading, a step for feeding the kneaded starting materials to a T die-type extrusion molding device and molding a sheet, and a step for adjusting the apparent gravity as desired by stretching under predetermined conditions.

Abstract: The problem addressed by the invention lies in providing a method for producing an inorganic substance powder highly-oriented thin film sheet with which it is possible to produce a sheet of uniform thickness while preventing the generation of impurities, improving sheet surface properties, adjusting apparent specific gravity, and the like. The method for producing a thin film sheet comprises a step for preparing a predetermined inorganic substance powder, thermoplastic resin, and auxiliary agent, a step for exposing the starting materials mixed at a predetermined mixture ratio to high shear stress while kneading, a step for feeding the kneaded starting materials to a T die-type extrusion molding device and molding a sheet, and a step for adjusting the apparent gravity as desired by stretching under predetermined conditions.

Abstract: Sulfur oxides are removed from a waste gas containing SO.sub.2 by: scrubbing the gas with an aqueous slurry containing Mg(OH).sub.2 as well as gypsum thereby to transform the SO.sub.2 into MgSO.sub.3 and to fix the same in this slurry; oxidizing the MgSO.sub.3 in this slurry to convert the same into MgSO.sub.4 ; filtering the slurry containing an aqueous solution of the MgSO.sub.4 thus formed and gypsum thereby to recover the gypsum; and adding Ca(OH).sub.2 to the aqueous solution of the MgSO.sub.4 of the filtrate thereby to convert, by double decomposition reaction, at least the greater part of the MgSO.sub.4 into Mg(OH).sub.2 and, at the same time, the Ca(OH).sub.2 into gypsum, the resulting aqueous slurry containing the Mg(OH).sub.2 thus formed as well as the gypsum being used for the above mentioned scrubbing of the waste gas. The double decomposition reaction in this process is carried out in the presence of seed crystals of gypsum to obtain gypsum of good quality.

Abstract: Sulfur dioxide can be removed from a combustion exhaust gas and converted to gypsum by first scrubbing a sulfur dioxide-containing combustion exhaust gas with an aqueous alkali sulfite solution to form an alkali bisulfite-containing aqueous solution and then treating, within a closed system, the thus formed aqueous bisulfite solution with a calcium compound. The efficiency of the sulfur dioxide removal can be increased greatly by adding a portion of alkali sulfite aqueous solution circulating in the system to at least a portion of filtrate from the gypsum separation process to precipitate metallic ionic impurities contained in the filtrate in the form of salts and separate these salts by filtration, and then recirculating the filtrate from the salt separation process to the absorption system.