Corn has become the fastest-growing ethanol matrix in Brazil over the last five years. Alcohol production from the grain has more than tripled since the beginning of the decade, with a CAGR of 16% from 2020 to 2024. This growth is extremely significant, especially when considering that sugarcane alcohol production saw a drop of around 30% over the same period, and has therefore leveraged corn ethanol to account for around 20% of the total bioethanol produced in the country.
The profitability of corn ethanol production, however, is not limited to the sale of ethanol. Plants that produce biofuel exclusively from the grain, or full plants, also extract profits from the sale of higher value-added by-products obtained after ethanol is produced. These plants treat the resulting syrup at the end of distillation to generate DDG (Dried Distilled Grains) and corn oil, so that one ton of corn generates an average of 420 liters of ethanol, 300 kg of DDG and 12 liters of corn oil.
Although corn oil is the item with the lowest productivity among the products obtained in the mills, its high added value makes it a co-product of great interest to the market – specifically to the biodiesel and animal nutrition markets. Because of the reward of this challenge, it is imperative to use specific processes and products to optimize the extraction of this material, and the main chemical input in this operation are corn oil demulsifiers (or CODs), such as the products in the ALKEST TW, ALKEST CSO lines and SURFONIC COD 400.
CODs are the main chemical additives used to break down the corn oil emulsion in the syrup. Dosed at 0.03% of the syrup, either pure or as part of formulations, demulsifiers are typically hydrophilic surfactants that adsorb at the oil droplet interface and displace emulsion-stabilizing components such as proteins and polysaccharides. By destabilizing the emulsion, the oil particles gain mobility and aggregate, separating from the aqueous phase.
The use of a demulsifier suitable for a plant’s specific syrup reduces oil separation time in tricanter centrifuges, which typically perform processes at around 90°C. Consequently, the use of these chemicals significantly lowers energy expenses in co-product extraction and generates greater productivity and profitability for the biofuel business.
Thus, demulsifiers such as those in the ALKEST and SURFONIC COD range are key products in the profitability of the corn bioethanol market and contribute to the diversification of the Brazilian energy matrix.
Luis Felipe Sugai / Rafael Ungarato
REFERENCES:
ASSOCIAÇÃO NACIONAL DO PETRÓELO, Painel Dinâmico Matéria Prima, Disponível no link.
NEVES, M., MILAN, P., VALERIO, F., MARQUES, V., DELSIN, F., et al., Etanol de Milho Cenário Atual e Perspectivas para a Cadeia no Brasil, 2021, primeira edição.
FANG, L., WANG, T., LAMSAL, B., Synergistic effect of surfactants and silica nanoparticles on oil recovery from condensed corn distillers solubles (CCDS), Industrial Crops and Products, Volume 77, 2015, Páginas 553-559.