The heat transfer efficiency will affect the drying effect of the dryer for grain
The dryer for grain can effectively ensure the overall efficiency of the drying process and the quality of the grain after drying in a high humidity environment. During the grain drying process, the grain dryer can ensure that the grain is not cracked or thermally damaged.
The dryer relies on the change of hot air to improve the speed of drying grain. After many experiments, the technicians have concluded the benefits of increasing the speed of the hot air in the dryer. Now I will share the conclusions for you: During the grain drying process, in the dryer cylinder, the convective heat exchange between the gas and the grain is the main heat transfer method, and its heat transfer efficiency directly affects the drying effect of the grain. The following are the approaches for improving the heat transfer efficiency of gas and grain:
(1) strengthen the thermal insulation of the cylinder, use a boiling furnace for heating, increase the temperature difference between the gas and the solid phase, and increase the temperature gradient;
(2) increase the heating area of the solid phase;
(3) increase the hot gas flow of the dryer and increase the hot gas flow rate. On the premise that the particle size of the wet grain entering the machine is fixed and the heating of the boiling furnace is designed, the airflow speed of the hot air is very important to speed up the heating speed. To improve the hot air velocity, the exhaust air and dust removal system at the end of the dryer and the hot air supply system at the head of the dryer must be reasonably designed. The air pressure and air volume of the exhaust fan should be appropriate. If the air pressure is too low and the air volume is too small, it will affect the exhaust air and reduce the output of the dryer; if the air pressure is too high and the air volume is too large, it will increase the power consumption and easily raise the temperature of the gas exhausted from the machine, thus increase the heat loss. The air pressure and air volume of the centrifugal blower that supplies air for fuel combustion should also reasonably be set. If the air pressure and air volume are too high or too low, it will affect the fuel combustion degree and combustion efficiency.