The article concerns technological measures to improve the environmental friendliness of food industry enterprises: in particular, aspects of processing waste from the alcohol industry with further use in agriculture (in animal feed). It is important to use methods to optimize the feeding of farm animals, allowing one to involve feed resources that do not have a harmful effect on health and productivity, while significantly reducing the consumption of grain components. This resource is dry distillery grains, which is a waste product of distillery production. Technologies of distillery bard processing include its evaporation with further drying. The main waste at the ethanol plant is whole stillage. It is centrifuged to separate thin stillage from wet grains. Thin stillage contains 5-10% of solids. For reducing energy consumption during the concentration process, it is possible to use a direct contact evaporator (bubbling evaporator). In this article, the bubbling evaporator design was developed. To justify the size of the evaporator, the temperature difference profile along the column length was determined. It is less than 1 and remains constant, which determines the high efficiency of heat transfer. The most effective parameters of the evaporation process according to moisture removal are a gas flow rate of 1.3–1.5 m3/h, air temperature of 400±15. Work results can be used in the design of scalable systems for thin stillage processing and applicable in medium-sized ethanol plants.