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Show - 3 - determine the possibilities of co-firing these biomass waste materials with pulverised coal whilst maintaining a high level combustion performance and minimum pollutant emissions such as NOx and 502, and minimum fouling and slagging. The IFRF is performing studies the co-firing of a range of bituminous coals with straw, waste paper and municipal sewage sludge. Research Facilities The majority of research described in this paper was undertaken using the IFRF, single burner, boiler combustion chamber simulator, fired typically at 2.5 MW total thermal input. The coals were prepared using a ball mill and classifier to a particle size distribution typically with 750/0 passing a 75 Ilm sieve. The coals for a blend were milled separately, stored, and subsequently blended using individual mass flow control, prior to a mixing chamber, as shown in Figure 1. In all experiments described, the IFRF Aerodynamically Air Staged Burner (AA5B), or derivations thereof, were used. This burner, the basic concept of \v hich is shown in Figure 2, has been used extensively at IJmuiden in recent years. A complete reference list for work undertaken using this burner is given in Reference 2. A derivation of this burner known as the Integrated Fuel Staged Burner (IF5B - see Figure 3) is also described in Reference 2, and was used in the co-firing experiments as the basis of a dual fuel burner, where straw and milled sewage sludge were fired through separate channels. In all other respects, the fuels were fired in simulation of actual power station boiler practice. |