Factors influencing the production rate and quality of lead sinter

The sintering characteristics of a typical Missouri lead concentrate were determined for two types of raw sinter mix: conventionally prepared and pelletized. The important sintering characteristics are sulfur elimination, sinter strength, production rate of sinter, permeability of the sinter bed, and bed temperature. These characteristics were analyzed statistically, and are described by an empirical model, in which proportion of returns, moisture content, air flow, bed height, size distribution of returns, and ignition time are the independent variables. The characteristics of a conventionally prepared sinter mix are most strongly affected by the moisture content of the raw mix. The characteristics of a pelletized sinter mix are not strongly affected by any of the independent variables. However, a pelletized charge gave a much higher production rate and a higher sinter quality as compared to a conventionally prepared charge. Recycle of off gas has a large deleterious effect on sinter production rate and quality. The results provide suggestions for improved operation of sinter plants.