Anonymous Ethanol Manufacturer (Agricultural Energy)

Dry grind ethanol production operates under dual market pressures: fuel ethanol demand driven by state and municipal blending mandates, and livestock feed demand for co-products like distillers dried grains with solubles (DDGS) and wet distillers grains with solubles (WDGS). This manufacturer — processing 13 million bushels of corn annually to produce 35 million gallons of ethanol and over 170,000 tons of distillers grains — faced compounding operational constraints. The dryer was a capacity bottleneck, beer column instability was limiting ethanol yield, and natural gas costs tied to the thermal oxidizer were eroding margins. In a continuous process where small variable shifts compound across interconnected unit operations, the cost of suboptimal control was measured directly in lost gallons and wasted energy.

Rockwell Automation implemented its FactoryTalk Analytics PavilionX platform — a predictive ML solution designed for closed-loop process optimization in continuous manufacturing environments. The system's core is a multivariable, non-linear model predictive controller that runs 24/7 to dynamically optimize the evaporator, dryer, and thermal oxidizer as an integrated system rather than isolated units. The deployment began with a joint requirements definition phase in which Rockwell engineers and plant personnel aligned on optimization targets and measurable benefit expectations before any configuration work began. In operation, the controller shifts drying load from the dryer to the evaporator to relieve the capacity bottleneck, regulates thermal oxidizer hotbox temperatures to reduce natural gas consumption, and manages syrup evaporator steam to stabilize beer column separation. A tailored moisture targeting algorithm enables the plant to run DDGS at higher average moisture, directly increasing co-product yield. The entire optimization loop operates on the existing equipment footprint without additional capital hardware.

The implementation delivered measurable gains across production throughput and energy performance within the existing equipment footprint. Ethanol production increased 12%, with throughput rising in step, as the freed dryer capacity and stabilized beer column translated directly into higher gallons per operating day. Energy efficiency improved by 9.9%, driven by reduced natural gas consumption from tighter thermal oxidizer control. Process consistency also improved: standard deviation in dryer moisture fell 3.3%, reflecting the controller's ability to maintain tighter targets continuously versus periodic manual adjustment.

• +12% ethanol production and throughput
• +9.9% energy efficiency improvement
• −3.3% standard deviation in dryer moisture
• $2.5M+/year estimated total installation value, based on industry average marginal values and natural gas cost savings

• Multi-unit MPC outperforms single-loop control: optimizing the dryer, evaporator, and thermal oxidizer as a coordinated system surfaced capacity gains that unit-level tuning alone would not have achieved.
• Shift drying load upstream: redirecting thermal work to the evaporator relieves dryer bottlenecks without requiring additional capital equipment.
• Co-product moisture targets are yield levers: tuning DDGS moisture upward increases co-product output alongside primary ethanol production.
• Define requirements before deployment: structured pre-implementation alignment between vendor engineers and plant staff was a stated contributor to outcomes exceeding expectations.
• Continuous automated control eliminates shift-to-shift variance, a persistent source of yield inconsistency in continuous manufacturing that periodic manual adjustment cannot match.