Briquetted cement prodn. - with high calcium sulphate dihydrate content, has improved storage properties over powdered cement

摘要

Process for briquetting cement comprises (a) mixing powdered cement with 2-4 wt.% water and (b) briquetting the mixt. in a rotary or stamping press. at a press. of 1500-500 kg/cm2 to maximum density. Due to the briquetting process, the plaster modifications present (hemihydrate and anhydrite) are converted into the calcium sulphate dihydrate by the constant internal press. of the moisture present. The briquettes give higher quality concretes etc., have improved storage properties cf. standard powdered cement, are easier to transport and handling costs. No special arrangements need be made for on-site storage (in contrase to normal bags of cement which must e.g. be piled onto pallets and e.g. packaged in protective film). Generally the briquettes are comminuted to the original particle size of the cement before use, when they have the technological properties of fresh cement.