DRYING UNIT Russian patent published in 2022 - IPC F26B19/00 F26B21/04 

FIELD: drying.

SUBSTANCE: invention relates to low-temperature drying of foodstuffs, e.g., beet pulp, and can be used in the food industry for preserving the essential nutrients, e.g., pectin, in the dried product. Drying unit comprises a low-temperature dryer consisting of a preparatory section and a final section, connected in series. Air is used as a heat carrier in the preparatory and final sections of the low-temperature dryer. In the drying unit, pipelines are used for the circulation of the coolant and air, as well as fans for injecting air and a heat pump unit. The low-temperature dryer includes a cyclone, an evaporator section and the condenser of the heat pump unit with the return of the heat carrier into the low-temperature dryer forming a closed circuit. The heat pump unit consists of a compressor, a condenser, a temperature control valve, and two sections of the evaporator. The line for dried air supply to the final section of the low-temperature dryer comprises an apparatus for adjusting the temperature of the supplied air, and the heat pump unit is equipped with lines for the supply of burning coolant vapours from the compressor to the evaporator sections and with solenoid valves used to supply coolant vapours to the evaporator sections. The heat pump unit is equipped with a second temperature control valve for changing the operating mode, said valve being independent of the first temperature control valve and activated alternately therewith.

EFFECT: drying unit can ensure the operation of a heat pump unit without depressurisation thereof or coolant loss.

1 cl, 1 dwg