Sustainability in manufacturing built materials : cement manufacturing using alternative fuel and raw material in cement kilns

Abstract

Cement manufacturing has a high impact on the ecological environment from “quarry to lorry”. Starting from excavation of limestone, raw material crushing and milling, clinker manufacturing, cement grinding and bulk & bag material transportation demands use of natural resources in the form of material and energy. Driving of sustainability initiatives in the cement industry has gained focus over a period of time and reducing the non-renewable energy usage in the thermal process of clinker manufacturing has been identified as a key area to drive. In the traditional cement manufacturing process, the thermal energy demand of the cement kiln is supplied through the use of fuel such as coal and heavy furnace oil which is a non-renewable energy source. The initiative to replace traditional fuel usage by using alternative fuel derived from the industrial wastes unfolds cement industry to drive sustainability in two aspects. Firstly, through replacing coal and hence conserving a non-renewable energy and secondly through making the cement kilns available under controlled conditions to thermally destruct hazardous and non-hazardous waste and thereby providing an environmentally sound final destination to dispose their waste to the industrial waste generators. The paper discusses how the cement industry in Sri Lanka, specifically the only fully integrated cement manufacturing facility operated by Holcim (Lanka) Ltd. derives this model to deliver sustainability in the cement industry.