1. Equipment specifications

The configuration of the size of the dryer is based on the actual local conditions and the requirements of the two important indicators of the productivity and precipitation range of the dryer.

If the requirement is 3000t corn with a moisture content of 26%, when the average ambient temperature is -5 ° C, the corn can be stored for about 15 days, worked for 20 hours a day, and dried to 30% moisture after 30 days. 5t / h small dryer with large drying capacity (converted to 5% water per hour, its drying capacity is 12 tons. Water / hour).

If the food production area is concentrated and the amount of grain processed during the drying season is large, a large high-temperature, high-efficiency and fast dryer can be selected according to the actual situation.

Production capacity

The equipment of the dryer should be large or small, because in most cases, when the harvest season meets the rainy season, it is necessary to play the role of the dryer. The large drying volume and small productivity cannot solve the problem.

State and local reserves, large and medium-sized dryers should be built in grain-intensive production areas. The service radius of the fixed dryer should be small or large, so as to reduce the transportation distance, reduce costs and improve efficiency.

The mobile dryer can be used in rural areas where grain production is not concentrated and small grain production areas in the south. The productivity is generally 2 ~ 5t / h. It is too small and is not welcomed by users. It is best to use one machine for multiple purposes. Grain types are also applicable to some cash crops. The service radius should be larger in order to play the role of a mobile dryer.

3. Heat source

When choosing a dryer, local energy resources must be considered to achieve reasonable utilization and reduce costs.

If there is a grain production area in a coal mine, it is advisable to use coal, anthracite or coke as the heat source. The price is economical, but the one-time investment for coal-fired hot air stoves is large.

There are oil fields and natural gas production areas, and light diesel oil, heavy oil or natural gas, and propane can be used as fuel for hot stoves. The use of such fuels is high, but the one-time investment for hot stoves is small.

The special seed dryer is suitable to use oil or natural gas hot air stove, because its wind temperature is stable and easy to control, which can ensure the germination rate of dried seeds.

4. Environmental conditions

Due to the different harvest seasons of various crops, as well as temperature differences during drying in the north and south, factors such as drying effects and operating costs must be considered.

For example, avoid drying the grain in low temperature and humid weather as much as possible in the coastal areas, otherwise the dehydration effect is poor, the productivity is low, and the drying cost is high.

Nearly half of the time in the northern region is drying below 0 ° C. The lower the external temperature, the greater the unit heat consumption required and the higher the cost. Therefore, the outer wall of the dryer and hot air pipes operating below 0 ° C in the north should be added with a thermal insulation layer to reduce heat loss.

5. Ancillary equipment

To complete the drying operation, the dryer must be equipped with some auxiliary equipment.

The continuous dryer should be provided with upper and lower level devices (or overflow pipes, etc.) in the grain storage section, the temporary storage bin in the process should be provided with a full bin level device, and the elevator should have automatic shutdown and block alarm devices.

The motor should be provided with an overload protection device and can achieve manual and automatic interlocking control. Grain discharge agencies should be able to achieve speed regulation or stepless speed change.

The temperature control instrument should be able to display the temperature of the hot air and the temperature of each section of grain, and be capable of high temperature alarm. In order to test the moisture content of the grain, a rapid moisture tester should be provided.