Summary:
There are three phases in condensing granulating: first, pre-cooling, the temperature of raw material will change from granulating point to solidification point; second, solidification, raw material will change from liquid to solid, the temperature of material is not change in this step; third, solid material cooling, raw material will go on cooling and solidify.
Time of meltwater pre-cooling: d(s):(tl-tk)/(tc-tk)=exp(hd d/dcdpd)
Time of constant temperature solidification: c(s):c=dpcLf/hc(tc-tk)
Time of solid material cooling: s(s):(tc-tk)/(ts-tk)=exp(hs s/dCsps
Main factors which affect granules quality:
1. Temperature of raw material: temperature of raw material could affect capacity of equipment directly.
2. Properties of raw material: different properties raw material has different granulating ability, it will affect granulating process, quality and specification. Main property: melting point (softening point), specific gravity, heat transfer coefficient, crystalline properties, viscosity and liquid surface tension.
3. Viscosity (or surface tension), temperature could affect granules quality.
Spray condensing granulating has bigger capacity, more uniform granules, higher granule rate and easier operation compared with conventional rotation belt condensing granulating.
