| 摘要 |
FIELD: drying thermolabile loose products such as groats. SUBSTANCE: method involves bifurcation of spent drying agent flow into main and auxiliary streams. Source product flowrate, dried product moisture content, temperature and flowrate of drying agent, pressure of drying agent at product layer inlet and outlet are measured. Superheated steam is used as drying agent; some portion of spent superheated steam is conveyed over auxiliary stream to heat exchanger for preheating source product. Moisture and temperature of source product downstream of heat exchanger and dried product flowrate are also measured. Present values of source product temperature downstream of heat exchanger are used to correct superheated steam temperature at drier inlet by adjusting steam superheater power. Portion of spent superheated steam to be conveyed over auxiliary stream is determined by present values of superheated steam temperature and flowrate at drier inlet, source product flowrate and temperature downstream of heat exchanger. Amount of moisture evaporated from product per time unit is determined by current values of dried product flowrate, moisture content of source and dried product. Ratio of this value to source product is continuously calculated, derivative of found ratio is determined by flowrate of source product, and flowrate of source product is controlled. EFFECT: improved power efficiency and environmental safety of drying process. 2 dwg, 2 tbl
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