Abstract
If the lime stone and the quartz rock with comparatively high purity are selected, γ－C2S can be obtained because of burning the rotary kiln. Al2O3 in the sample that had been obtained after it had burnt it was about 1.7mass％, and Fe2O3 was about 0.1mass％. The scorch point temperature was 1450～1500℃. Moreover, even if a special operation was not done during cooling, γ－2CaO・SiO2 was able to be obtained. The amount of the CO2 emission when γ－C2S was manufactured from the lime stone and the quartz rock became 695.6kg－CO2/t, and usually reached a small value in the case of portland cement. γ－C2S was able to be burnt instead of the calcium hydroxide that industrially generated the CaO raw material as a by－product. The amount of the CO2 emission that lies manufactured of γ－C2S can be greatly decreased with 159.3kg－CO2/t compared with the case to use the lime stone because there is no amount of the CO2 emission with the CO2 of the raw material.
