Preparation of CWS from a low-rank coal

MEI G;CICCU R;TILOCCA, MARIA CATERINA;MAZZELLA, ALESSANDRO

2011-01-01

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Abstract

The feasibility of using Sulcis coal. for preparing coal water mixtures (CWM) is being studied since many years by the “Coal Processing Team” at the University of Cagliari. Presently the Sulcis coal, coming from the only coal mine in Italy, classified as sub-bituminous high-sulfur coal (about 5% S), is burned in the ENEL power station of Portovesme (Sardinia, Italy), where it is transported by trucks using a public road about 15 km long. This study aims at assessing the feasibility of preparing coal water mixtures to be delivered to the power station via a 3 km long pipeline. It includes the following steps: 1. Study of the rheology of the CW mixture 2. Assessment of fluid dynamics and design of pipeline 3. Economic viability in relation with the social costs A number of tests have been performed until now with the goal of studying the rheology of the slurry prepared with the Sulcis coal, with particular regard to size distribution, coal/water ratio, reagent addition and the chemistry of the water. This paper deals with the results obtained with the research carried out so far showing that it is possible to prepare CW mixtures also with the Sulcis coal, previously considered unsuitable for this purpose. Finally basic considerations underlying the design of the pipeline in the frame of the socio-economic situation of the area are given and discussed.