As ethanol production increases, the supply of distiller's grains also increases. Distilled grains are waste produced by distilleries after alcohol production, containing a high amount of fiber and protein, with protein content ranging from 25-35%. After processing, they can be used as cow feed and are a good source of energy and protein for beef cattle, reserve cows, or calves. However, wet distiller's grains have a high moisture content, large volume, are difficult to store, and typically have a shelf life of less than 5 days, making them prone to spoilage. Therefore, drying distiller's grains is necessary before processing them into cow feed.

Introduction of distiller's grain rotary dryer

The initial moisture content of wet distiller's grains is usually between 60-70%, and it is necessary to reduce the moisture content to 12-15%. The shelf life of distiller's grains at this moisture level is greatly extended, reaching 60-90 days. The most common drying equipment for distiller's grains on the market currently is a rotary dryer. This equipment utilizes hot air to fully contact the material inside the drum, achieving efficient dehydration through rotation and rolling. The distiller's grains with a moisture content of 60-65% are transported by a screw conveyor to rotary dryer for downstream drying. The material is continuously picked up and dispersed below the baffle, moving forward in a spiral shape. The built-in multi-layer baffle structure allows the materials to be fully mixed, dispersed, and thrown. The materials exchange heat with the hot air, and the moisture evaporates quickly. The materials that have reached the drying effect are quickly discharged from the drum under the action of the hot air, while the wet materials that have not reached the drying effect cannot be discharged quickly due to their own gravity. The material that achieves the drying effect completes the drying process and is discharged by the screw conveyor. The drum is equipped with an impact cleaning device inside to prevent materials from adhering to the drum wall. The airflow direction is: the hot blast stove fan pressurizes the air and sends it into the hot blast stove for combustion and heating, reaching a temperature of 600-950 ℃. After passing through the dryer, the material is sucked into the dryer by the induced draft fan for drying and evaporating moisture. After three layers of heat exchange, the air temperature drops to 55-60 ℃ and is discharged from the dryer. Water containing powder dust is collected by a cyclone dust collector and purified by a wet dust collector before being discharged to standard conditions.

The subsequent processing technology of dried distiller's grains

After the moisture content of distiller's grains decreases, although it facilitates storage, the problems of poor palatability and low digestibility still exist. To convert it into high-quality beef cattle feed, a series of refined post-treatment processes are required, mainly including physical crushing, nutritional enhancement, and fermentation treatment.

1. Physical crushing

The dried distiller's grains have a hard texture, and direct feeding can easily cause gastrointestinal damage in cattle. It is necessary to use a hammer crusher to grind dry distiller's grains to a particle size of 2-3mm, increase the surface area, facilitate subsequent nutrient adsorption, and improve feed palatability.

2. Nutritional reinforcement

The lack of capacity and some trace elements in distiller's grains requires the addition of additives to balance the nutritional structure. Common additives include corn flour, soybean meal, salt, vitamins, and calcium bicarbonate, which can supplement energy, essential amino acids, calcium, and maintain electrolyte balance.

3. Fermentation

Untermented distiller's grains have a pungent odor and contain substances that inhibit microbial growth. Add lactic acid bacteria, yeast and other fermentation agents, put the mixed materials into the fermentation tank, and ferment at 25-30 ℃ for 3-7 days to achieve successful fermentation.

Complete all the steps above to make distiller's grains cattle feed.

Processing distiller's grains into cow feed effectively recycles waste and increases economic benefits. The distiller's grains dryer is an important part of this process. If you have any questions about the distiller's grains dryer, please feel free to contact us at any time.