Biofuels Industry SolutionDryer/Evaporator Application

The ChallengesIn the fuel ethanol industry, producers often use multiple dryers to help ensure a quality product is made, and as a result, energy efficiency becomes a critical factor in the overall success of the process. However, a challenge exists in consistently measuring moisture. Producing lower quality products often cause various handling and transporting issues, leading to customer dissatisfaction.

In addition, managing a parallel syrup evaporator efficiently and recovering energy to increase yields, while operating thermal oxidizers within environmental limits, creates a constant challenge for achieving operational excellence. The ideal plant would operate at consistently high distillers grains product moisture, effectively balance syrup evaporation with current production, and balance multiple parallel centrifuges with gradual, slow adjustments to maintain its energy and material balance.

Rockwell Automation recognizes these challenges and offers an application focused on delivering valuable dryer and evaporator control for better optimization, performance and economic value.

Rockwell Software SolutionsOur solutions leverage Rockwell Automation’s 100+ years of industry innovation, experience and global support. Industry best practices are incorporated into every application, which is built upon a composite application framework that leverages a Service Oriented Architecture (SOA). This scalable solution, when combined with library-based content, offers personalization options that promote faster user adoption and time-to-value.

Beer Column

Whole Stillage

Centrifuge Feed Wet Cake Pad

Syrup Tank

Thin Stillage

Steamor

Vapor

Dryers

Dryers

Evaporators

Reduce energy consumption

and production costs,

increase efficiencies and

reduce emissions Benefits:• Increase stillage processing capacity 4-10%

• Decrease energy costs per gallon 3-5%

• Increase Dried Distillers Grains with Solubles (DDGS) yields 1-1.5%

• Reduce moisture variability 25-50%

Process SolutionsOur solutions leverage Rockwell Automation’s 100+ years of innovation, experience and global support. Industry best practices are incorporated into every application, which is built upon a composite application framework that leverages a Service Oriented Architecture (SOA). This scalable solution, when combined with library-based content, offers personalization options that promote faster user adoption and time-to-value.

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Publication RSAPBF-AP004C-EN-P – October 2019 Copyright ©2019 Rockwell Automation, Inc. All Rights Reserved. Printed in USA.

The Rockwell Automation Dryer/Evaporator Model Predictive Control (MPC) Application controls evaporator solids and dryer moisture, while managing stillage inventory and syrup usage, to provide consistent, optimum DDGS quality and yield. Where additional energy benefits are available, steam system control is included as part of this solution. This stillage management application integrates with other parts of the plant that are heat or material connected with the evaporator or dryers, providing maximum heat recovery, while stabilizing the plant during process and rate changes.

Centrifuge Feed Control

The whole stillage level is managed with continuous, gradual adjustment to the centrifuge feed controllers. Operators are able to limit and bias individual centrifuge rates with flow limits and turn individual centrifuges off-control in the event of operational limits or issues.

Stillage Inventory Management

This application manages stillage inventories as needed across whole stillage, thin stillage, and syrup tanks. It responds automatically to Clean In Place (CIP) and other process events to stably manage inventories with respect to current plant operating rates.

Evaporation Control

This solution scope includes stillage inventories and evaporator solids integrated with distillation and other heat recovery. Controllers that balance evaporator operations with distillation and thin/syrup tank level limits may feed to and draw from the evaporator and each centrifuge, along with the evaporator steam and beer feed flow.

Drying Control

This solution manages syrup addition and natural gas or other fuel flow to the dryer to control DDGS and intermediate dryer moistures. An estimated product property is based on a real-time model of operator tests or is used to back up a calibrated analyzer. In addition, the steam generation system is reviewed and controlled on this portion of the plant as needed, either for improved regulatory tuning or integrating steam generation models within the MPC solution.

This application is part of Rockwell Automation’s complete solution offering for the biofuels industry.

Dryer/Evaporator Application

Provides predictive control and optimization of the process to improve efficiencies and reduce costs and emissions