heavy coal slurry

Coal-water slurry fuel (CWSF) is a mixture of pulverized coal and water, typically containing 50-70% coal and 29-49% water, with small amounts of chemicals to stabilize the mixture. This slurry can be handled like a liquid fuel and burned in specialized boilers designed for oil combustion.1

The primary challenge in burning CWSF is ensuring the rapid evaporation of water to allow the coal particles to ignite and combust efficiently within the boiler's residence time. This is achieved through fine atomization of the slurry, preheated combustion air, and effective recirculation of hot gases. While water evaporation slightly reduces thermal efficiency, it can be more cost-effective than dewatering wet coal or converting oil-fired systems to dry coal systems. The economic viability of CWSF is closely tied to the price and availability of traditional liquid fuels.1

Unlike traditional coal slurries, which are transported via pipelines and then separated from the water before burning, slurry fuels like CWSF are fired directly into boilers. This method offers advantages such as fixed costs after initial construction, lower labor requirements, and less land use compared to rail or truck transport. However, significant water usage and potential environmental concerns regarding water pollution are important considerations.2