Multistage drier, esp. for cereals - operates under vacuum with state-to-stage pressure gradation, each being heated by vapour from following stage

摘要

A multi-stage drier for vegetable material, partic. cereals incorporates vacuum producing equipment to establish a pressure lower than atmospheric in each stage. The pressure is lowest in the first stage and increases up to the last stage. Each stage except the last is heated by vapour produced in the following stage where the pressure is higher. The drier gives a considerable economy in fuel compared to existing techniques. In addn. there is no danger of fire in the drier and no atmospheric pollution.