Drying grain using solid fuel

Abstract

The use of alternative sources of liquid (gaseous) fuel to produce a coolant, including for grain drying, has been studied in contrast to burning conventional fuels, which hinders their use. A characteristic feature of the use of combustion units for burning plant waste is a sufficiently long ignition and preheating, preceding the drying. At the same time, a large amount of heat is accumulated in the furnace casing, which can be partially used for batch drying for the next batch of grain and completely for the latter, which will increase the efficiency of the process. Drying is one of the main operations in post-harvest grain processing, the fate of the crop depends largely on the quality of drying. Both flow and periodic drying are common in farms. Periodic drying, as a rule, uses the same dryers as for flow or specialized. The technology of this drying in dryers equipped with liquid or gas furnaces is well developed and does not cause difficulties - kindle the furnace, cyclically dry the grain to the conditioned moisture, cut off the fuel supply, cyclically cool and unload the dryer. The pause between the drying of adjacent lots without ignition and heating of the furnace is determined by the cooling time of the masonry to the temperature of stable ignition and burning of volatiles plus 150-200 °С, depending on the moisture content of solid particles of plant waste. The duration of ignition is a function of the mass of the furnace chamber, its heat capacity, the temperature of the flue gases and the heat transfer coefficient. At ignition of liquid fuel its duration is not less than 20 min. To dry the last batch of grain, the mass of the burnt chamber must be at least 0.7 times the mass of the grain in the dryer. The duration of heating the furnace is completed by stabilizing the temperature of the flue gases at the outlet of the exhaust fan, but not less than 1 hour.