CONTROL METHOD FOR PROCESSES OF DRYING AND STORAGE OF PLANT MATERIALS WITH INCREASED CONTENT OF FATTY ACIDS

摘要

FIELD: heating, drying.;SUBSTANCE: invention relates to automation of technological processes of drying and storage of crops, especially oil-bearing-crops. The method comprises drying oscillating in the temperature regime of plant materials in gravitationally moving layer of shaft dryer consisting of alternating in series zones of heating and cooling; processing of raw materials with antioxidant and feeding it to the silo storage with periodic active ventilation; supply of exhaust air after heating zones for preheating of plant materials; the discharge of the resulting steam-air mixture of the exhaust air after zones of cooling, preheating of plant materials and active ventilation in a cyclone for removal of suspended particulate matter comprised in it, followed by cooling and dehumidifying in the evaporator and heating first in the condenser of the heat pump and then in the heater; feeding of the prepared in a heat pump conditioned air to the zones of heating and cooling to form a closed loop, and stabilization of hydrothermal characteristics of the raw materials during drying and storage with impact on the flow rate, temperature and moisture content of the conditioned air supplied to the zones of heating and cooling of the dryer, and the flow rate of antioxidant depending on the flow rate of the dried plant raw material the novelty is the fact that after each heating zone mixing of plant raw material with an antioxidant is carried out, and for obtaining conditioned air the steam ejector heat pump is used, comprising a steam generator with electric heating elements and the safety valve, the ejector, the evaporator, the cold-receiver, the heat-exchanger-wasteheat exchanger, the condenser, the thermal expansion valve, the condensate collector working in a closed thermodynamic cycle; in the cold-receiver of the steam ejector heat pump the steam-air mixture is cooled to the dew point temperature and its dehumidification is carried out by condensation of moisture contained in it on the cooling surface of the cold-receiver in the form of droplet liquid; the resulting conditioned air from the cold-receiver is discharged in three flows: one is directed to the cooling zones of the dryer, the second for the active ventilation, and the third in series to the heat-exchanger-wasteheat exchanger, the condenser of steam ejector heat pump, the heaters and then to the heating zones of the dryer; in the steam generator working steam is obtained and fed in two flows, one of which is directed to heaters for additional heating the conditioned air prior to supply to the heating zones of the dryer, and the other - to the ejector nozzle, creating vacuum in the evaporator with lower temperature of the coolant boiling, which is used as water; the mixture of the coolant steams and working steam after ejector is fed to the condenser for heating the conditioned air prior to the heaters; one part of the condensate formed in the condenser is fed into the evaporator to replenish the loss of water and its another part to the heat-exchanger-wasteheat exchanger and further with the condensate formed in the cold-receiver and the heaters is first discharged into the collector of condensate, and then into the steam generator to form a closed loop; according to the current values of humidity of plant raw materials in the zones of heating the flow rate of the antioxidant is determined at the steps of mixing; according to the amount of water steam in the steam-air mixture after drying and silos the ejection coefficient of steam ejector heat pump is determined with the impact on the ratio of the working steam flow supplied to the ejector nozzle, and the ejected coolant steam from the evaporator by varying the flow rate of the working steam, and the productivity of the steam generator is determined based on the influence on power efficiency of its electric heating elements, depending on the working steam pressure supplied to the ejector.;EFFECT: invention enables to provide stabilization of quality of plant raw materials with increased content of fatty acids.;1 dwg