Heat energy conversion during drying and cooling of large scale animal feed production plant
In the production process of a large-scale animal feed mill factory, the products coming out of the extruder machine and animal feed pelletizer machine must be dried or cooled by certain equipment before they can be packaged, stored or sold. Therefore, drying and cooling are indispensable links in the processing of these products. About the heat energy conversion and utilization in this process, a brief introduction is as follows:
1. Heat energy conversion during drying process
Materials with higher moisture content will evaporate by absorbing the heat in the drying medium through the action of the drying medium in the feed dryer. At the same time, the temperature of the drying medium itself is reduced due to the release of heat, and the moisture evaporated from the material is discharged from the drying system along with the flow of the drying medium. The replenishing drying medium absorbs the heat released by the steam in the heat exchanger and increases in temperature. At the same time, the steam becomes condensed water and is discharged from the heating system.
2. Thermal energy conversion during cooling
Compared with the drying process, the natural clean air is used as the medium in the cooling process, and the materials with a certain temperature and moisture are cooled and dehumidified.
Take the commonly used countercurrent particle cooler as an example: In the cooler, the material flows from top to bottom, and the cooling air flows from bottom to top, forming a countercurrent flow with the material. The material in the lower part provides the heat required for water evaporation and air temperature rise in the top-down process, and the temperature is close to the ambient temperature. As the upper air absorbs the heat released by the particles during the bottom-up travel process, the temperature and moisture capacity are increased. Therefore, the purpose of cooling and dehumidifying the feed pellets is realized. The hot and humid air after work is discharged from the cooling system by the cooling fan.
3. Thermal energy conversion in the stabilizer
For some special materials, such as shrimp material, the maturation degree is required. After being extruded, it still needs a period of time for further heat preservation and heating. This process is usually carried out in a stabilizer.
Generally, the stabilizer is made into a jacket type, and a certain number of steam pipes are arranged in the cavity to keep the temperature in the cavity stable at about 100°C, so that the material is further matured and stabilized.
In this process, steam is continuously consumed, and the heat energy of the steam is continuously transferred to the material through the pipe wall, which increases the temperature of the material and matures.
4.Animal feed equipments introduction
①Scope of Application
Mainly applicable to the cooling of various pellet materials.
Use counter-flow cooling principle, full and uniform cooling.
Use special slide valve discharging mechanism to discharge.
The discharging mechanism runs smoothly and reliably, the discharging is smooth.
The temperature of pellets is not higher than room temperature by +3-5℃ after cooling.
Use mechanical leveling device, the discharging is accurate and sensitive.
Multilayer material drying, use the space effectively,put up productivity.
Recycle partial waste heat to improve the thermal efficiency. Material distributed in the sieve,good drying uniformity, material is stationary relative to sieve, following sieve to move ahead,reduce grinding rate effectively, drying time can be adjusted according to detail requirement. Mainly used for drying food and extruded feed.