Grain dryers play a vital role in modern agriculture, especially in the humid southern region, which effectively solves the problem of grain moisture. The following is the working principle of grain dryers:
1️⃣ Hot air circulation: The grain dryer first converts heat energy into hot air, and evaporates the moisture of grains through hot air circulation. The circulating dryers on the market can be used with various burners, such as burners that burn oil, natural gas, electricity, coal and various plant materials.
2️⃣ Mixed flow drying: Hot air and grain flow both in the same direction and in the opposite direction, which is called mixed flow. When hot air passes through the grain layer, it transfers heat and moisture to the grain. The hot air transfers heat to the grain, raising its temperature. After the grain is heated, the moisture evaporates into the air and is discharged as exhaust gas. The dried hot grain flows downward to the slow-suction section, and the temperature and moisture of the inner and outer layers of the grain are balanced through the slow-suction section, achieving uniform precipitation. After the grain is slowly refrigerated, it enters the cooling section. After cooling, the grain is cooled to the grain storage temperature and then discharged from the grain discharge section.
3️⃣ Grain loading process: The grain in the hopper is lifted to the top of the main silo by the elevator, and then the grain is sent into the drying box by the upper auger until it is full.
4️⃣ Drying cycle: The grain discharge mechanism continuously discharges the grain at the bottom of the drying section to the lower auger, and the lower auger sends the grain to the elevator to the upper auger, and then the upper auger sends the grain to the refrigeration bin. Under the action of its own weight, the grain in the refrigeration bin slowly moves from top to bottom to the four drying sections. The moment the grain enters the drying section to the moment it enters the drying section for the second time is a cycle.
5️⃣ Hot air circulation drying: The air indirectly heated by the hot air furnace is sent into the hot air chamber of the drying section under the action of the centrifugal induced draft fan. The hot air continuously passes through the grain layer in the drying section horizontally from the hot air chamber. The direction of the hot air flow is intersected with the direction of grain movement. The hot air flow and the grain are in full contact, so that the grain is heated, heated, and precipitated. The waste gas after the grain layer is dried is discharged from the waste gas chamber. In this way, the cycle drying is realized repeatedly until the moisture content of the grain meets the required warehouse standard.
During the period when the grain enters the slow recovery stage, although there is no ventilation and heating, the grain still maintains a certain temperature when it just leaves the drying stage. Due to the temperature and humidity difference between the surface and the inside of the grain, the moisture inside the grain is promoted to gradually move outward and gradually tend to balance, creating conditions for the next cycle of heating and precipitation.
Post time: Apr-18-2025