WASTE GYPSUM REGENERATION PROCESSED MATERIAL

PROBLEM TO BE SOLVED: To recycle waste gypsum of an environmental pollution waste material into a harmless water permeable material (a board or a pipe) by processing the waste gypsum with a chemical to make harmless and joining with a resin. SOLUTION: A pulverized material of the waste gypsum is coated with a hydrolyzed aqueous solution using 0.02-1% silane coupling agent and dried or an unsaturated polyester resin made by mixing 0.5-4% non-hydrolyzed coupling agent with a resin is added into the pulverized material of the waste gypsum by 10-30% to mold and cure as an integrated composite material. In such a case, the amount of fluorine to be eluted into water from the composite material is controlled to ≤0.8 ppm of the environmental standard. COPYRIGHT: (C)2011,JPO&INPIT