326 IAC 8-5-6 Fuel grade ethanol production at dry mills

Sec. 6. (a) This section applies to fuel grade ethanol production plants constructed or modified after April 1, 2007, that meet the following conditions: (1) Are dry mills and have no wet milling operations. (2) Use fermentation, distillation, and dehydration to produce ethanol and dried distillers grain and solubles (DDGS). (3) Have combined potential VOC emissions of twenty-two and seven-tenths (22.7) megagrams (twenty-five (25) tons) or more per year from the following processes: (A) Fermentation, distillation, and dehydration. (B) DDGS dryer or dryers. (C) Ethanol load-out operations. (b) The following definitions apply throughout this section: (1) "Dry mill" means an ethanol production operation that uses the whole corn kernel to produce a meal that is then used to produce alcohol. The byproduct of a dry mill is the DDGS. (2) "Fuel grade ethanol production plant" means an operation that produces ethanol that is then denatured with a denaturant to make it unfit for human consumption. (3) "Wet milling" means a process by which corn is soaked or steeped to soften the corn kernel so that it can be separated into its various components, such as the following: (A) Gluten. (B) Germ. (C) Protein. (D) Fiber. (E) Starch. (c) The owner or operator of a fuel grade ethanol production plant that is a dry mill shall install and operate at least one (1) of the following control devices for VOC emissions from the plant: (1) A thermal oxidizer with an overall control efficiency of not less than ninety-eight percent (98%) or resulting in a volatile organic compound concentration of not more than ten (10) parts per million (ppm). (2) A wet scrubber with an overall control efficiency of not less than ninety-eight percent (98%) or resulting in a volatile organic compound concentration of not more than twenty (20) parts per million (ppm). (3) An enclosed flare with an overall control efficiency of not less than ninety-eight percent (98%). (d) The source shall determine initial compliance with the control efficiency requirement within sixty (60) days after achieving maximum production levels but no later than one hundred and eighty (180) days after startup. (e) The owner or operator of a fuel grade ethanol production plant that is a dry mill shall ensure and verify initial and continuing compliance with the control efficiency requirement by doing the following: (1) If using a thermal oxidizer, the owner or operator shall meet the following requirements: (A) The three (3) hour average operating temperature of the oxidizer, as measured by a continuous temperature monitor, must be greater than or equal to the minimum operating temperature established during the most recent compliance demonstration. (B) Maintain continuous temperature records for the thermal oxidizer and the three (3) hour average operating temperature used to demonstrate compliance during the most recent compliant stack test. (C) The three (3) hour average duct pressure or fan amperage, as measured by a continuous parameter monitoring system, must be within the normal range established during the most recent compliance demonstration. (D) Maintain daily records of the duct pressure or fan amperage for the thermal oxidizer. (2) If using a wet scrubber, the owner or operator shall meet the following requirements: (A) The pressure drop across the scrubber must be within the normal range established during the latest stack test. The pressure drop of the scrubber must be monitored at least once per day when the associated emission unit is in operation to ensure that the pressure drop across the scrubber is within the normal range established during the latest stack test. (B) The scrubber flow rate must be greater than the minimum flow rate for the scrubber during normal operation. The scrubber flow rate must be monitored at least once per day when the associated emission unit is in operation to ensure that the flow rate of the scrubber is greater than the minimum flow rate established during the latest stack test. (C) Maintain daily records of pressure drop and flow rate for the scrubber during normal operation. (3) If using an enclosed flare, the owner or operator shall meet the following requirements: (A) Maintain a flare pilot flame when the associated emission unit is in operation and continuously monitor the presence of a flare pilot flame using a thermocouple or any other equivalent device to detect the presence of a flame when the associated emission unit is in operation. (B) Maintain records of temperature or other parameters sufficient to demonstrate the presence of a pilot flame when the loading rack is in operation.