Objective The aim of the project is to save fuel gas by utilising hot stove waste gas as a drying and carrying medium for granular/pulverised coal in a blast furnace coal injection scheme at BSC's Ravenscraig site, Scotland. Traditionally, the gases generated in a fuel fired boiler are used for this purpose.To replace the coke used in the production of iron, the proposer is installing a new coal injection system which entails pulverising and drying raw coal prior to inputting it into the furnace. In this process the coal is transferred from storage hoppers to two coal pulverising mills. During the pulverising process the coal is usually dried by means of gas-fired dryers. The pulverised dried coal is conveyed from the mills by the gaseous combustion products. In this scheme, however, the drying and conveying medium to be used is blast furnace stove waste gas suplemented by burner combustion products when necessary.Stove waste gas will be transported by fan to a combustion heater for final temperature adjustment to around 200 deg.C prior to use as the drying and carrying medium. Close to this fan is an inlet so that cooling air can be drawn from the atmosphere when the stove waste gas temperature is higher than required.A preliminary examination of the likely operating status of thegas-fired burners shows that with coal of 8-10% moisture content and stove waste gas at 200-220 deg.C they will normally be supplying a small proportion of the heat required. In this condition they can rapidly be turned up to full in the case of any disturbance in the supply of stove waste gas.To show the performance of the stove waste gas system a testing and monitoring programme is proposed over a period of 4 months to determine on-line effictiveness and to enable a direct measurement of thermal gain. One advantage of using waste heat gas is the safety aspects conferred by the low oxygen content but this has been higher than envisaged and has necessitated considerable redesign and increased the cost of the project substantially over that originally anticipated. The additional cost of the design, installation and testing of dueting + valves plus process control modifications has been L 320000 which has increased the total cost of the project by 42 % and extended the payback time on this project to over 7 years. There is every indication that the knowledge gained would enable replication to be achieved at very much less cost. Programme(s) ENG-ENDEMO C - Programme (EEC) of demonstration projects and industrial pilot projects (EEC) in the energy field, 1985-1989 Topic(s) 3.4 - INDUSTRY Call for proposal Data not available Funding Scheme DEM - Demonstration contracts Coordinator BRITISH STEEL PLC EU contribution No data Address UK - LONDON SE1 7SN United Kingdom See on map Total cost No data
