Recycling of municipal solid waste for cement production: pilot-scale test for transforming incineration ash of solid waste into cement clinker

Incineration ash of municipal solid waste accounts for a great portion of the matter in landfills, and minimization of resource consumption and recycling of waste are important factors for ensuring the future welfare of humankind. The study presented in this paper reports a technology for producing cement from incineration ash of municipal solid waste, incineration ash of sewage sludge and other wastes such as aluminium dress acid copper slag. As incineration ash of municipal solid waste contains chlorine, special attention should be paid to fixing the chlorine within the cement. It was verified that proper treatment (formation of calcium-chloroaluminate) is capable of fixing the chlorine. In order to confirm the efficacy of this technology before it is used on an industrial scale, a pilot-scale test (50 tons/day) was conducted. The quality of the resulting cement is sufficient to enable the cement to be put to practical use. Furthermore, the tested process does not cause secondary pollution. Consequently, 50% of raw materials for cement production can be obtained from incineration ash of municipal solid waste. (C) 2001 Elsevier Science B.V. All rights reserved.