Cooling polymer chips in silo - in which air is blown in near bottom of silo while it is being filled or emptied

摘要

Polymer chips are cooled in a storage blending silo by blowing gas or vapour through them. The cooling medium is pref. introduced at the bottom of the silo and is blown through while the silo is being filled or emptied. The cooling medium can be conditioned or contain reagents for treating the polymer. Alternatively it can be air. More specifically the exit of a silo has an annular channel which is supplied with air from a fan via a heat exchanger. While the silo is being filled, air at about 40 deg.C enters through a grid and flows in counterflow up through the polymer chips. The polymer enters the silo at about 80 deg.C and the air leaves at 78 deg.C. When compared with a fluidised bed, the air consumption is reduced from 83300 kg/hr to 33000 kg/hr and the power consumption from 82 - 54 kW. USE/ADVANTAGE - Cooling is simpler than using a fluidised bed and consumes less powe