Ethanol plants have found a way to turn distillers’ grain into a valuable by-product rich in protein and fiber. What used to be waste is now considered highly nutritious and inexpensive animal feed. But with that comes challenges to overcome. While wetcake can be sold locally, the shelf life is too short for transport over long distances or be storage for extended lengths of time. This is where we come in and can help you with drying DDGS.
Drying DDGS opens a world of possibilities. 
Grains , such as corn, rice, and wheat, are used in the production of alcoholic beverages and are also the raw materials for ethanol production. Due to their nutritious composition, both brewers’ spent grain and ethanol waste is great as animal feed. But the challenges you face when drying DDGS depends on the properties and origin of the feedstock and can be hard to tackle.
Challanges to face.
The variations in particle size could affect nutrient digestibility and palatability, as well as mixing efficiency, pellet quality, bulk density. Particle size and particle size uniformity of feed ingredients are therefore more often than not important considerations for manufacturers of feeds or feed supplements. Although, DDGS product streams are notorious for their differences in particle size. Wich in some cases could be a challenge to the drying process where the drying isn’t uniform. A second challenge is the explosion risks that come with drying DDGS with the traditional drying techniques. In high concentrations and in high temperatures, dust can become explosive. Drying is also highly energy-consuming. Even if drying distillers’ grain opens a wealth of commercial opportunities. More and more companies take issue with the environmental consequences of such energy use.
How can these issues be solved?
Swedish Exergy knows that DDGS drying is a sensitive process. You can damage the DDGS by adding foul taste by drying with an incorrect process at the wrong temperature with a longer residence time in the dryer. It can also cause burning and/or stripping the DDGS from valuable minerals and proteins that the animals need. Instead, a stable and optimized drying process can improve the product quality, shelf life and nutritious value of the DDGS.
Let us show you what we mean.
The superheated steam dryer for drying DDGS.
Our solution is a closed, pressurized system where the wet product is exposed to superheated steam. The steam serves as a transport gas for the product in the dryer. The heat is transferred to the steam and suspended product through the super heater surfaces from the heating medium. Meaning that the heating media is never in contact with the product or the steam inside the dryer. Therefore flue gas, steam, thermal oil or electricity can be used as heat source for the dryer.
Dried product and superheated steam are separated in a cyclone and the steam is recirculated. Part of the dried product is recirculated back to the mixer, where it is mixed with wet product. The partially dry mixture is then fed into the dryer. Water in the wet product becomes steam in the dryer and is discharged through a pressure control valve, to maintain constant pressure in the dryer. With Exergy Superheated Steam Dryer the operating temperature and pressure within the dryer is optimized for optimal drying, with a residence drying time of between 5 – 10 seconds where you get a uniform drying as result.
Optimal solutions.
The DDGS from the superheated steam dryer has an increase value in by-pass protein. It gets fully sterilized in the drying process and the DDGS is not oxidized due to lack of air in the dryer. Due to the Oxygen free environment in the dryer there is No fire and explosion risk. As the dryer is a closed loop system there is No emission to atmosphere – No VOC or odor treatment needed. The Superheated steam dryer can recover at least 80% of the energy that is put into the dryer. resulting in a consumption of only 150 kWh/ton water evaporation.
The current problems faced in the industry are eliminated with Exergy Superheated Steam Dryer.