Liquidation process of treated organic waste by burning thereof in cement-making rotary furnaces

摘要

The proposed liquidation method of treated organic waste, in particular meat and bone meals, waste fats and another treated veterinary waste of animal origin, by incineration thereof in rotary cement kiln when burning cement is carried out in such a manner that treated organic waste with maximum moisture content of 50 percent, minimum heating value of 11 MJ.kge-1 and with formation of 50 percent by weight of ash, at the most, is added in a rotary cement kiln as a portion of the total amount of fuel either directly into the flame via a main burner and/or via a calcining burner and/or via an auxiliary burner, and/or the treated organic waste is added into said rotary cement kiln hot portion with temperatures above 1400 degC, whereby such amount of the treated organic waste is added into the rotary cement kiln, which evolves by its burning up to 90 percent of heat energy needful for achieving effective temperature for cement burning and simultaneously the amount of the treated organic waste is controlled to maintain amount of phosphorus oxide, expressed as Pi2Oi5 in clinker below the level of 2 percent. This means that the added treated organic waste burns in the kiln under oxidation kiln atmosphere in excess of combustion air and under generation of non-toxic combustion products and ash. Heat energy evolved by this burning is thus employed for effective cement burning, whereby the non-toxic combustion products are partially caught during counter-current cement burning on the ground raw material mixture and on clinker being just formed, and ash arising by incineration of the treated organic waste containing bones reacts quantitatively with clinker mass. Phosphorus oxide, analytically expressed as Pi2Oi5 exhibits in amounts up to 2 percent a mineralizing effect on formation of clinker phases.