Co-combustion of coal and textiles in a small-scale circulating fluidised bed boiler in Germany

Textile wastes are usually disposed of in landfill sites. However, landfilling is becoming increasingly expensive and restricted and, therefore, alternative ways are being explored to either recover the material or energy content of these wastes. This paper examines the recovery of energy by co-combustion of these wastes with coal in a circulating fluidised bed combustor (CFBC). It also investigates the effect of different amounts of fuel blending. Of the 83,200 tonnes of textile production waste arising in Germany in 1995, only 18,400 tonnes are suitable for co-processing with coal. If all this textile waste is co-combusted with coal in a CFBC, a 5% textile waste blend gives a maximum CFBC power station size of 122 MW and a 20% textile waste blend gives a maximum size of 24 MW. An analysis of transport costs showed that the ideal location for a CFBC power station in Germany is the district of GieBen, for larger scale plants, while the Freiburg or Munster areas are best suited for smaller plants. Using textile production waste in a CFBC power station reduces the efficiency and increases the capital cost. However, the textiles have a positive value to the power station if the normal textile waste disposal cost of ECU 135/tonne is included. Hence, although the textiles have a higher transport cost than coal, the overall fuel cost is improved when textiles are employed. The most economic size for a CFBC power station is 5 MW for a 20% textile waste blend and 20 MW for a 5% textile waste blend. (C) 2000 Elsevier Science B.V. All rights reserved.