| 摘要 |
PURPOSE:To make any and easy setting of the temperature of kneaded concrete possible and contrive to improve the efficiency of utilization of low temperature gas by a method wherein kneading water and the low temperature gas are brought into contact with each other and agitated each other in an agitating tank and, after that, fed to a mixer in order to knead them with aggregate and cement. CONSTITUTION:Aggregate and cement are respectively charged in separate metering tanks 4 and 5 so as to charge them by the amounts corresponding to the set ratio of them. On the other hand, the amount in the predetermined ratio of kneading water is supplied from a metering tank 10, in which the kneading water is fed by means of a pump 12, to an agitating tank 8. In parallel to the supply of the kneading water, the amount, which corresponds to the required temperature, of low temperature gas is supplied from a liquefied nitrogen vessel 16 through a flow control valve 17 to the agitating tank 8. The supply of said low temperature gas can be controlled with the flow control valve 17. Even when the kneading water and the low temperature gas are turned into the kneading water carrying ice by coming into contact with each other, the resultant kneading water is turned into the form of sherbet by being agitated through the rotation of an agitating screw 9. After that, the resultant admixture is charged into a mixer 1 so as to be kneaded together with the aggregate and the cement in order to produce low temperature concrete. |
