Submitted to: Cereal Chemistry
Publication Type: Peer reviewed journal
Publication Acceptance Date: 2/1/2006
Publication Date: 2/15/2006
Citation: Wilkins, M.R., Belyea, R.L., Singh, V., Buriak, P., Wallig, M.A., Tumbleson, M.E., Rausch, K.D. 2006. Analysis of heat transfer fouling by dry-grind maize thin stillage using an annular fouling apparatus. Cereal Chemistry. 83:121-126. Interpretive Summary: Dry grind corn (DGC) processing is the primary method for producing fuel ethanol in the United States. In DGC facilities, energy consumption is a major issue, particularly when condensing thin stillage in evaporators. Thin stillage primarily consists of soluble material remaining after ethanol fermentation. In thin stillage evaporators, scale covers the surface of the evaporator in a process known as fouling. Fouling scale reduces the energy efficiency of evaporators, causing increased energy usage. In this study, an annular fouling probe was evaluated to determine if it could measure thin stillage fouling rates with little variability. Four batches of thin stillage were collected from a DGC facility. A small amount of variability in fouling rate was observed among samples from the same batch. Fouling rates of batches were different from one another.
Technical Abstract: Dry grind corn (DGC) processing has grown in recent years as demand for ethanol has increased in response to the discontinued use of methyltertbutylether (MTBE) as a fuel oxygenate. Fouling of thin stillage evaporators has been identified as an important energy consumption issue in DGC facilities. Four batches of DGC thin stillage were analyzed for fouling rate and induction period using an annular fouling probe. Variability in fouling rate among replicate tests from the same batch and variability of fouling rate and induction period among batches was observed. A relatively small amount of variability in fouling rate (COV< 7.1%) was observed among replicates from the same batch. Differences in fouling rate and induction period were observed among batches.