SYNTHETIC UTILIZATION OF WASTE WOOD IN IRON AND STEELMAKING PROCESS

摘要

A purification system of exhausted gas from refining furnace in iron and steelmaking process is proposed for synthetic utilization of waste wood as a charcoal absorbent. This system could solve the problems of both the treatments of heavy metals contained in wasted preservative-treated wood and dioxins in the exhausted gas. The effect of temperature, atmosphere and holding time on the specific surface area and pore size distribution of a charcoal carbonized from Cryptmeria is examined, to clarify the carbonization conditions for the properties of charcoal. The results are as follows. The specific surface area has a maximum at 1073K of carbonizing temperature in N_2+O_2 atmosphere. The maximum specific surface area of the charcoal in this experiment is 582m~2/g, which is about 74 percent of that of commercial activated charcoal. The behavior of Cu, Cr and As in CCA preservative-treated wood during the carbonization is examined. Although most of the Cr and Cu remained in charcoal, more than half of As was released during carbonization.