Kawasaki Jukogyo Kabushiki Kaisha

Electric Power Development Co., Ltd.

Kao Corporation

Sumitomo Heavy Industries, Ltd.

Lion Corporation

Mitsui Engineering and Shipbuilding Company Limited

Nippon Shokubai Co., Ltd.

Nippon Shokubai Kagaku Kogyo Co., Ltd.

Shoichi Takao

Shuhei Tatsumi

Hayami Ito

Mitsugu Kamao

Kazuhiko Nakaoji

Hayami Itoh

Takashi Watanabe

Takashi Kuwabara

Kaoru Aoki

Kunizo Shinano

Nitaro Suzuki

Satoshi Yamada

Hideyuki Tahara

Tsuneo Tsubakimoto

Hiroya Kobayashi

Toshio Tamura

Kenji Rakutani

Takakiyo Goto

Takayuki Ogawa

Yoshihiro Kajibata

Hideaki Ito

Kenichiro Hayashi

Naokazu Kimura

Akio Nakaishi

Masazumi Ito

An additive for a carbonaceous solid-water slurry which excels preeminently in the ability to disperse a finely powdered carbonaceous solid in water and, when used only in a small amount, permits production of a carbonaceous solid-water slurry which possesses high concentration, exhibits high fluidity, and precludes change of viscosity due to aging, a method for the production of the additive, and a slurry composition are provided. The additive to be used for high concentration of carbonaceous solid-water slurry comprises a specific water-soluble copolymer and contains a low molecular copolymer (a) having a weight weight-average molecular weight in a range or from 1000 to 39000 and specific ratios of adsorption relative to a carbonaceous solid and a clayish mineral and a high molecular copolymer (b) having a weight weight-average molecular weight of not less than 40000 and specific ratios of adsorption relative to a carbonaceous solid and a clayish mineral at a weight ratio, (a)/(b), in the range of from 10/90 to 99/1, the met hod is for the production of the additive, and the slurry composition is produced by the incorporation of the additive.

Additive for carbonaceous solid-water slurry, method for production

Dispersant for aqueous slurry of carbonaceous solid and aqueous

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.

Preparation of deashed high solid concentration coal-water slurry

A high-concentration coal-water slurry of a coal concentration as high as 71 percent by weight at a viscosity of 2,000 cp (at 25.degree. C.) can be produced by first coarsely crushing a starting coal, further pulverizing 95 to 30 percent by weight of the coarsely crushed thus obtained, subjecting the finely pulverized coal thus obtained, together with the remainder of the coarsely crushed coal, to crushing in a wet-type crusher, and pulverizing and adjusting the coal particles to a particle size constitution of 20 to 30 percent by weight of 200-mesh size and larger and 80 percent by weight or less of 350-mesh size and smaller.

Process for producing high concentration coal-water slurry

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.

High concentrated coal-water slurry is produced by coarsely crushing coal, thereafter pulverizing the coarsely crushed coal, together with water and a slurry dispersant, according to necessity, in a wet-type ball mill, and feeding back one portion of the finely pulverized coal slurry thus obtained into the inlet of the wet-type ball mill.

Process for producing high-concentration slurry of coal

Growing community of inventors

Akashi, Japan

Shoichi Takao