Siouxland Ethanol – Emissions Solutions for CHP Conversions – Case Study

When Siouxland Ethanol, located in Jackson, Nebraska, USA decided to invest in a combined heat and power system (CHP), or cogeneration, it needed to make decisions regarding the plan`s air abatement and compliance. The company wanted to take its current system, a heat recovery steam generator (HRSG) offline and replace it with a boiler to form a cogeneration plant. With this approach, the steam generated by the new boiler requires a regenerative thermal oxidizer (RTO) to process the dryer`s emissions, which are produced when dry distiller`s grain with solubles (DDGS) are dried. Siouxland`s overall goal was to find a better way to create steam and destroy emissions other than the traditional HRSG/thermal oxidizer (TO) system. The company decided to invest in a CHP system, which produces efficient steam with a cogeneration system, and required an RTO to handle the dryer emissions. This solution offered more flexibility to the operation.