SU1225987A1 - Method of grain drying - Google Patents

Description

The invention relates to the technology of drying by active ventilation of bulk agricultural raw materials, such as grains, oilseeds, legumes, grass seeds, and is intended for use primarily in agriculture, the procurement system and the food industry.

The purpose of the invention is to increase productivity and quality while reducing specific energy consumption.

The drawing shows the technological scheme of the grain drying process in the group unit of ventilated bins according to the proposed method.

The diagram shows the block I of the ventilated bunkers (one row) of the drying stage and the block 2 of the bunkers (second row) of the drying and cooling stage, individual fans 3 to these bins, connected through flow regulators 4 to the common collectors 5 for the heat carrier connected from the furnace 6. For suction of outside air to the bunkers of the unit 2, in front of the fans 3 there are nozzles 7 installed with flow regulators.

The diagram shows a cascade heater 8 and a tank 9 for extracting the mixture of grain with a feeder 10 between them. For transfer to the tank 9 of the original grain in arrow I1 or its mixture with recirculation along transport line 12 from block 1, there is nori 13. In the same tank, the grain feeds nori 14 from block 1 of bunkers when it is overloaded to block 2, as well as the transport block - nor 15 when pumping it during drying. The nori 14, after it is finally dried and cooled, passes the grain through line 15 in arrow 16 to the warehouse for storage.

Both bins are loaded with norium 17, into which the grain comes from the cascade heater 8, and the grain is distributed to the bunkers by pipelines 18 and 19, as well as transport lines 20 and 21, respectively, for blocks 1 and 2.

For controlled release of grain from bins, there are outlet valves 22.

The specific implementation of the method is illustrated by the example of drying wheat seed grain moisture 22-24% at an ambient air temperature of 18 ° and a relative humidity of 55%. The initial grain enters the drying in the direction of arrow 11 and rises noria 13 to the cascade heater 8, in which it is blown at a coolant temperature of 120-180 ° C, which corresponds to heating the grain within 37-42 ° C (heating of the grain rises from 37 to 42 ° C during loading, as the moisture content of the mixture decreases). In the loading hopper of the unit 1, the valve 22 is opened for the production of a part of grain 2-5 times higher than the flow of the original. From the hopper being loaded, the grain enters transport conveyor 12 to elevator 13, in which it mixes with the original. The mixture is kept in the tank 9 for 4-5 minutes, and then is fed into the heater 8 by the feeder 10, from which the pressure 17 goes through the pipeline 18 and the transport line 20 to the unit 1.

According to this scheme, the grain will move until the bins of the block 1 are fully loaded. After filling the bins by 20-30%, the fans 3 are turned on. The grain in the bunkers during their charge is loaded with coolant at 50-70 ° C. After loading the bins, the valves 22 are closed and the temperature of the coolant is reduced to 40-55 ° C. When the intermediate humidity of 18% is reached, the grain is pumped through the heater 8 according to the scheme outlined and under the same conditions as during loading, but is fed with norium 17 through conduit 19 by transport line 21 to the bunker of block 2 for final drying. Drying with simultaneous cooling are unheated air, as its relative humidity is 55%. In the bins of block 2, they can also make binning for 1.5-2 hours. In the middle of the drying period in block 2, the grain is pumped once into the free bunker of the same block, then finally dried and cooled, then with norium 14 in direction of arrow 16 is fed to storage in the warehouse.

Claims (3)

1. THE METHOD OF DRYING GRAIN by actively ventilating in the group block of bins by blowing grain at the stage of drying in one row of bins, pouring the grain at intermediate humidity into bins of another row in which drying and cooling are carried out, characterized in that, in order to increase productivity and quality with a reduction in specific energy consumption, when loading each hopper of the first row, it is purged in a moving layer at a coolant temperature of 50–70 ° С with the selection of part of the grain and mixing it with the original wet grain Mr., after which for 3-6 minutes they carry out the tracking of the mixture, and then convective heating with simultaneous drying at a coolant temperature of 120-180 ° in a cascade heater to the maximum temperature allowed for the initial grain, after the hopper is completely filled, the selection is stopped and drying continues layer to an intermediate moisture content that is 2–4% higher than the standard one, at a coolant temperature of 40–55 ° С, pouring into the corresponding hopper of the second row is carried out through a heater, in which the grain is blown at the same parameters as when filling the hopper, § а and drying is carried out in a fixed layer by atmospheric air, which L at a relative humidity of over 65% is heated by 3-10 ° С. ( 2. The method according to π. 1, characterized in that _ at the stage of drying, the grain is pumped 1-3 times through its second-row hopper and heater, in which the purge is carried out at the same parameters as when filling the first-row hopper. 3. The method according to PP. 1 and 2, characterized in that, in the bunkers of the second row produce graying grain for 1.5-2 hours >