Forward and reverse circulation drying process of grain dryer
Author: DingliDate: 2017-05-29
A grain dryer is a dryer assembly. Food dryer, a variety of equipment collectively. Can also be grain drying machine, such as corn drying machine, rice drying machine, drying machine, rice dregs drying machine, we can all be called grain dryer. According to the direction of relative movement between grain and air flow, dryer can be divided into cross flow, mixed flow, downstream, reverse flow and reverse flow, mixed countercurrent, and mixed flow.
At ordinary times, we use a lot of clockwise and reverse circulation drying type. Pure counterflow dryers are seldom produced and used, and most of them are used in conjunction with other airflow dryers, which are used in cooling sections of downstream or mixed flow dryers to form a counterflow and mixed counterflow dryer. The advantage of countercurrent cooling is that the natural cold air can contact the grain sufficiently, and it can increase the cooling rate and decrease the cooling height. The counterflow, mixing counterflow and mixing drying machines utilize their respective advantages respectively, so as to achieve high temperature and rapid drying, increase drying capacity, not increase unit heat consumption, and ensure grain quality and water content uniformity.
Drying process of vertical and reverse circulation low temperature grain dryer:
1.The heat transferred to the cooling chamber, the low temperature grain drying machine drying cabin, the cabin in the preheating heat pipe, hot air to grain, direct heating, heat conduction and heat radiation in the dryer machine through the heat radiating device for grain gas heating, gas temperature, the grain drying bin to preheating chamber the temperature required for drying.
2.The grain which needs to be dried is conveyed to the feed port, and then enters the preheating bin after the operation of the unloading valve, and the grain enters the drying bin after the exhaust, preheating, heating and ventilation in the preheating bin.
3.In the grain drying cabin through the ventilation, heat, heating, drying into the cooling chamber in the cooling chamber; grain after pumping gas, heat, cooling after the discharge valve discharge cooling bin, thus completing the material circulation of hot air drying.
4.The hot and humid air generated by heating and drying in the drying bin can be condensed into liquid water by condensing the cooling device, and the heat energy released by condensation can be used many times.
5.The energy of the dried grains in the cooling bin is cooled by gas, and the gas is heated to become hot air. The temperature of the grain in the cooling bin is also cooled and cooled. After further heating, the heat radiation device enters the drying bin to heat and dry the grain.