Advanced Multi-Product Coal Utilization By-product Processing Plant

The installation of an advanced coal ash beneficiation processing plant is proposed by LG&E Energy, Corp at the 2,200 MW Ghent Power Plant in Ghent, Kentucky. The Ghent Power plant is owned by Kentucky Utilities Company, a regulated subsidiary ofLG&E Energy, Corporation. The demonstration plant will be a near commercial scale installation and will produce: . 156,000 tons per year ofpozzolan which substantially exceeds ASTM C-6I 8 criteria for loss on ignition (LOI), fineness and strength index. 16,000 tons per year of ASTM C-330 and C-331 compliant high grade lightweight aggregate. 16,000 tons per year graded fill sand. 1,500 tons per year of high quality polymeric filler. 8,000 tons of recycled carbon fuel. . ... The proposed plant represents the next step in coal utilization by-product (CUB) beneficiation, addressing the entire CUB stream and a wide array of quality issues. The process generates a pozzolan that can be used at higher portland cement substitution. levels in concrete (i.e. 30% versus the current 20%), while producing better strength and performance than what is available from unprocessed ash. Coarse ash is beneficiated to produce either lightweight aggregate, suitable for use in concrete masonry units such as blocks, or graded fill sand for construction applications while unburned carbon is concentrated for re-use as a supplemental fuel. The process also produces a clean, very fine-size material (~3 to 4 /lm median particle size) suitable for use as a polymer filler or specialized pozzolan. With this suite of highquality, consistent products, the potential for total CUB utilization can be realized. The manufacture of portland cement is one of the highest generators of CO2 of any industrial process, releasing approximately I ton of CO2 per ton of cement produced. The 156,000 tons of high quality pozzolan will displace an equivalent amount of portland cement, representing a direct and significant green house gas offset. The process is based upon a hydraulic classification and froth flotation technology developed at The University of Kentucky CAER over the past decade. The technology, which incorporates several patents, can process both ash stored in existing disposal ponds and/or directly from the plant. Raw feed is classified by size into a pozzolan stream (-200 mesh) and a coarse stream (+200 mesh). These coarse materials are further classified and concentrated into a block sand product and coarse carbon product by spiral concentrators. The fine pozzolan stream is treated with a patented reagent system and the fine carbon is removed via froth flotation. The pozzolan stream is then concentrated, filtered and dried. A small stream from the froth cell is further processed hydraulically to produce a material with a finer particle size. This material is suitable for use in a number of applications including a polymer additive.