PREPARATION OF HYDRAULIC COMPOUND USING SILICON SLUDGE FROM SILICON WAFER MANUFACTURING PROCESS

摘要

PURPOSE: A hydraulic composition with waste silicon sludge solid is provided to recycle the waste sludge without an elaborate refinement process or a heat treatment process at high temperatures by utilizing properties of the silicon sludge which is produced in a fine powder type appropriate for expression of hydration property. CONSTITUTION: A hydraulic composition is composed of Portland cement and waste silicon sludge solid. The waste silicon sludge solid takes a possession of 3-40 weight % among the total weight of the hydraulic composition. A particle size distribution of the waste silicon sludge has a bimodal distribution which shows at least two peaks. A lower peak with a smaller sized particle among at least the two peaks is at 5 microns or below. Contents of silicon and a silicon oxide among the waste silicon sludge solid have 50 weight % or more among the total weight of the waste silicon sludge solid. A production method of cement admixture includes the following steps; the waste silicon sludge is centrifuged; the waste sludge solid is yielded removing fats in the waste silicon sludge; and the silicon and the silicon oxide are concentrated refining the waste silicon sludge.