Abstract: A cement clinker producing system, capable of providing a gas containing a carbon dioxide gas at a high concentration by increasing a carbon dioxide gas concentration for a part of an exhaust gas, includes a cyclone preheater to preheat a cement clinker raw material, a rotary kiln to burn the preheated cement clinker raw material so as to provide cement clinker, a calcination furnace to promote decarbonation of the cement clinker raw material, a clinker cooler to cool the cement clinker, a kiln exhaust-gas discharge passages to discharge an exhaust gas generated in the rotary kiln, a combustion-supporting gas supply device to supply a combustion-supporting gas having a higher oxygen concentration than air, a combustion-supporting gas supply passage to guide the combustion-supporting gas to the calcination furnace, and a calcination furnace exhaust-gas discharge passage to discharge a carbon dioxide gas-containing exhaust gas generated in the calcination furnace.

Abstract: To provide a device for removing radioactive cesium from waste material containing radioactive cesium, doing so at low energy and in a dependable manner. The removal device 1 for radioactive cesium is provided with: a rotary kiln 41 which is provided with a burner 41b supplying from the kiln outlet an organic matter O3 contaminated with radioactive cesium, and an inorganic matter charging port 41a supplying from the kiln inlet inorganic matter S4 contaminated with radioactive cesium, and which is employed to burn the organic matter O3 together with the inorganic matter S4; and a recovery device cooling tower 51, a cyclone 52, a bag filter 53 for recovering cesium that has volatilized in the rotary kiln. A drying/crushing device (dryer 21, crusher 22) for drying and crushing the organic matter O1 prior to charging the radioactive cesium-contaminated organic matter to the rotary kiln can be provided.

Abstract: To provide a method and an apparatus for removing radioactive cesium from waste containing radioactive cesium at low cost. A radioactive cesium removal apparatus 1 including: an incinerator 22 for burning an inflammable waste polluted with radioactive cesium; a suspension preheater 23 for, with the combustion exhaust gas G5 and a sensible heat of the incineration ash of a combustible C discharged from the incinerator, generating calcium oxide or/and magnesium oxide from a source of calcium oxide or/and a source of magnesium oxide, cyclones of the suspension preheater being arranged in multistages; a rotary kiln 21 for burning an inorganic substance S polluted with radioactive cesium together with the calcium oxide or/and the magnesium oxide and the incineration ash D3 including the radioactive cesium; and collectors 31, 32 for collecting cesium volatilized in the rotary kiln.

Abstract: To provide a device for removing radioactive cesium from waste material containing radioactive cesium, doing so at low energy and in a dependable manner. The removal device 1 for radioactive cesium is provided with: a rotary kiln 41 which is provided with a burner 41b supplying from the kiln outlet an organic matter O3 contaminated with radioactive cesium, and an inorganic matter charging port 41a supplying from the kiln inlet inorganic matter S4 contaminated with radioactive cesium, and which is employed to burn the organic matter O3 together with the inorganic matter S4; and a recovery device cooling tower 51, a cyclone 52, a bag filter 53 for recovering cesium that has volatilized in the rotary kiln. A drying/crushing device (dryer 21, crusher 22) for drying and crushing the organic matter O1 prior to charging the radioactive cesium-contaminated organic matter to the rotary kiln can be provided.

Abstract: To provide a method and an apparatus for removing radioactive cesium from waste containing radioactive cesium at low cost. A radioactive cesium removal apparatus 1 including: an incinerator 22 for burning an inflammable waste polluted with radioactive cesium; a suspension preheater 23 for, with the combustion exhaust gas G5 and a sensible heat of the incineration ash of a combustible C discharged from the incinerator, generating calcium oxide or/and magnesium oxide from a source of calcium oxide or/and a source of magnesium oxide, cyclones of the suspension preheater being arranged in multistages; a rotary kiln 21 for burning an inorganic substance S polluted with radioactive cesium together with the calcium oxide or/and the magnesium oxide and the incineration ash D3 including the radioactive cesium; and collectors 31, 32 for collecting cesium volatilized in the rotary kiln.

Abstract: A burnt product is produced by burning a raw material containing chromium, in which the fine-grained portion is removed. Even in the burnt product produced from a raw material containing chromium, the chromium (VI) content is reduced.

Abstract: A burned product containing 100 parts by weight of C2S and 10 to 100 parts by weight in total of C3A and C4AF, a cement admixture obtained by grinding the burned product, and a cement containing 100 parts by weight of a ground Portland cement clinker and 5 to 100 parts by weight of the burned product. The cement is good in both initial strength and long-term strength.

Abstract: A burned product containing 100 parts by weight of C2S, 10 to 100 parts by weight of C2AS, and 20 parts by weight or less of C3A; a cement admixture prepared by grinding the burned product; and a cement containing 100 parts by weight of ground portland cement clinker and 5 to 100 parts by weight of a ground product of the burned product.

Abstract: A burned product containing 100 parts by weight of C2S, 10 to 100 parts by weight of C2AS, and 20 parts by weight or less of C3A; a cement admixture prepared by grinding the burned product; and a cement containing 100 parts by weight of ground portland cement clinker and 5 to 100 parts by weight of a ground product of the burned product. Through use of a cement admixture produced by grinding the burned product of the present invention, cement products exhibiting low heat of hydration and good fluidity can be obtained.