Thin Stillage from Wheat-Based Ethanol Production is an Effective Fertilizer

Thin stillage (TS) is a byproduct from ethanol production. Accumulation of this byproduct has led to the need for possible means of its utilization. Researchers from University of Saskatchewan are now studying the possibility of utilizing TS from wheat-based ethanol production plant as a fertilizer.

Three rates of TS (50, 100, and 200 kg N per hectare) were applied using two methods (broadcast and injection) and applied to wheat (Triticum aestivum L.) and canola (Brassica napus L.) fields. Conventional urea (46-0-0) was also applied at the same rates as TS for comparison. Plant parameters were measured over two seasons.

Results revealed that TS produced similar or greater crop yield and nutrient recovery compared to urea fertilizer, especially when it was injected. This probably was due to the presence of plant nutrients such as phosphorus and sulfur in the TS, as well as its relatively high nitrogen content, in the form of ammonium. The injection of TS was a more effective application method since its placed nutrients closer to the growing crop roots when injected in soil.

The results of this study suggest that land application of TS can be an effective solution for waste TS management.