Pilot Experiments on Co-Processing Oversized Products Screened from Aged Refuse in Cement Kiln

Abstract

Re-processing of aged refuse with particle size of 100mm, heating value above 3000kcal/kg above, chlorine content of about 0.13% was added into cement kiln as alternative fuels using screw conveyor. The results show that: except for NOx, emission rate and concentrations of TSPs, HCl, HF, SO2, CO from cement kiln flue gas were increased and volatized significantly after adding alternative fuels. Dosage of 2t/h of alternative fuels affected little on kiln system, so, main process parameters were normal and no more substantial fluctuations, but, the amount of feeding coal at calciner were adjusted more frequently. Element of S in hot raw material into the kiln seemed no significant changes while K and Cl content was significantly increased within the manageable range. Compressive strength, flexural strength, water demand for normal consistency, surface area of clinker all reduced when using alternative fuels, initial setting time and final setting time were increased compared with clinker saturation. Adding alternative fuels saving of coal, but the actual effect of alternative fuel was less than theoretical results, indicating that intermittent feeding mode was not desirable.