Abstract: Described herein is a bacterium having high antimutagenicity against mutagens and belonging to the genus of Lactobacillus. The mutagens may comprise both a base-pair change mutagen and a frameshift mutagen. The bacterium preferably has high intestine reachability and can be Lactobacillus casei.

Abstract: This invention discloses (1) a dispersant for an aqueous carbonaceous solid slurry, which comprises a water-soluble copolymer having an average molecular weight of 1,000 to 500,000 and obtained by polymerizing (A) 0.1 to 7 mol % of a polyalkylene glycol mono(meth)acrylate type monomer, (B) 5 to 94.9 mol % of a sulfoalkyl (meth)acrylate type monomer, (C) 5 to 94.9 mol % of an unsaturated carboxylic acid type monomer, and (D) 0 to 20 mol % of other monomer (providing that the total amount of the monomers is 100 mol %) and/or a salt of the water-soluble copolymer and (2) an aqueous carbonaceous solid slurry composition, which comprises 100 parts by weight of as carbonaceous solid and 0.01 to 5 parts by weight of the aforementioned dispersant.

Abstract: The present invention relates to a process for preparing a coal-water slurry comprising the steps of screening coal into a coarse-grained coal and a fine-grained coal; subjecting said coarse-grained coal to gravity classification to classify into a low ash coal, a middle ash coal and a high ash coal; wet grinding a mixture of the fine-grained coal, the middle ash coal and part of the low ash coal, and subjecting same to flotation; preparing a first slurry having a solid concentration of 40-60 wt. % from the low ash froth resultant from flotation; and mixing another part of the low ash coal with this first slurry and wet grinding this mixture. This process can accord the solid concentration of the product slurry with an optional target value by adjusting the amount of the low ash coal mixed with the first slurry, and can use the remaining low ash coal not to be added to the first slurry for the purpose of preparing the second product slurry.

Abstract: This process, which comprises subjecting coal to gravity classification to classify into a low ash coal, a middle ash coal and a high ash coal; deashing the middle ash coal by flotation; and using the deashed middle ash coal together with the low ash coal as the materials for producing a coal-water slurry, provides a low ash content and high solid content coal-water slurry in a high coal recovery as well as economically. This coal-water slurry is able to handle, store and burn as are fuel oils.

Abstract: When exhaust gas from a coal-burning boiler containing NO.sub.x as well as SO.sub.x is subjected to NO.sub.x removal by catalytic reduction of the NO.sub.x with ammonia and the coal ashes contained in the gas are separated, the coal ashes are contaminated by a certain quantity of ammonium compounds produced from the SO.sub.x and the ammonia excessively used. The ammonium compounds in the coal ashes are decomposed into ammonia and a sulfur compound by heating by the hot gas at a temperature in the restricted range, viz. 350.degree. to 700.degree. C., thereby to release ammonia into the gas preferentially to the sulfur compound. The ammonia thus released is recycled to the NO.sub.x removal step.

Abstract: A process is disclosed for calcining cement-clinkers by using a calcination apparatus having a generally cylindrical calcining furnace which is composed of (a) a throat part, (b) a spouted bed and (c) an uppermost chamber longitudinally connected in series with an upper part of a combustion chamber having a separate heat source. The calcining apparatus is disposed between a suspension type raw material preheating device and rotary kiln or a fluidized bed calcining device wherein, cement raw materials, which have been partly calcined in the said raw material preheating device, are fed in the vicinity of the upper end of the said spouted bed while a jet fluid of a high temperature flue gas passing through the throat part under high speed from the said combustion chamber and rising upwards is admixed with a tangential flow of a high temperature exhaust gas introduced into the vicinity of the upper end of the said spouted bed from the said rotary kiln or from the fluidized bed calcining device.