If brewer's grains with high water content want to process the moisture to the reuse stage within a certain period of time, drying equipment becomes an indispensable item. In the current industry, distiller's grains are mainly dried by heat transfer Therefore, the temperature of the brewer's grain drying equipment is particularly important, so how much is the temperature of the equipment controlled when drying the distiller's grains?
Distillers grains are a kind of high-moisture material. In the process of dehydration and drying, it is easy to stick to the wall or dry incompletely if the temperature is low. If the temperature is too high, the phenomenon of paste is easy to occur. The drying quality of distiller's grains must not only strictly control the temperature inside the barrel, but also ensure that the distiller's grains do not deteriorate during drying.
When distiller's grains with higher moisture content enter the equipment barrel, high-temperature flue gas also enters from the same end. At this time, under the action of a large temperature difference, the water on the surface of the lees can be quickly evaporated and dried, and the temperature at the entrance can reach 450 ° C. At high temperature, it can realize instantaneous mass and heat exchange with the high-moisture lees, and most of the water are taken off quickly to ensure the heat value of distiller's grains is stable.
When the water on the surface of the distiller's grains evaporates to a certain degree, it will enter the constant speed stage. The internal temperature of the equipment barrel is generally controlled at 300 ° C, which can better ensure the drying quality during the drying process of the distiller's grains. At this time, if the distiller's lees are dried once, it will cause external gelatinization of the distiller's grains, affecting quality and color. Dingli adopts a two-stage air dryer, the lees are highly dispersed and suspended in the air stream, the surface area for heat and mass transfer between gas and solid phases is greatly increased, and the volume heat transfer coefficient is improved, at the same time, the appearance and stability of lees can be guaranteed.
It can be seen that there is a certain change in the temperature during the drying of lees, which requires us to design the drying process according to the characteristics of lees and production requirements to achieve the high-quality goal of lees drying and maximize the reuse of distiller's grains.