Method of treating industrial waste in fluidised bed reactor

The method feeds low grade coal, calciferous material and alternative fuels to a fluidised firing bed (1). They are converted into calciferous materials and toxic gases are neutralised. The use of primary air (2) from beneath and secondary air (3) from the side creates horizontal zones with temp. distribution, from the bottom upwards, of 780 deg C to 850 deg C at a pressure of 150 to 20 hPa. Combustion is started pref. using oil to create a cloud of hot ash particles. Combustion gases pass through a separator (6), with the fine particulates being fed back (9) to the reactor at a rate of 80 to 100 g/m of primary air, and the gases being used for steam raising. Larger solids are mixed with calciferous materials in a transport reactor at 830 deg C to 900 deg C for conversion into aggregate for the cement and building industries.