Influencing factors and evaluation system for Carbon–Calcium pellet performance in a pyrolysis furnace

Abstract

In the new process of CaC2 production, C–Ca pellets need to be pyrolysed in a prepyrolysis furnace before being placed in a CaC2 furnace. In this paper, the factors influencing the performance of composite pellets in a pyrolysis furnace are studied experimentally. A comprehensive performance-evaluation system is established to calculate and evaluate composite pellets comprising five raw materials. The pyrolytic rate, compressive strength, and dust concentration of the composite pellets are tested through thermogravimetry, universal pressure tester and dust concentration detector, respectively. The effects of C/Ca ratio, temperature, time and raw material composition on these properties are explored. Results show that during the pyrolysis of the composite pellets, the C-containing raw materials have a significant effect on various performance indicators. With increased C/Ca ratio, the pellet pyrolysis rate and compressive strength show a downward trend; with increased pyrolysis temperature and time, the pellet pyrolysis rate, compressive strength and activity show an upward trend; with a change in raw material composition, the pellet activity and dust concentration change significantly. The comprehensive properties of CaO + coke and CaO + anthracite are superior to those of other raw materials in all aspects, and this finding is in line with the industrial-production practice.