Common Development and Scale-Up Challenges for High Water and Energy Use Processes
Session Chairs
- David Reeder, Cargill
- Raj Dasari, Myriant
Session Description
This session will provide case studies and examples of the challenges in dealing with aqueous process streams and how these challenges are handled. Because feedstock and process streams are often relatively dilute, traditional separations technologies can have high energy use and can be difficult to develop, demonstrate and characterize at a scaled down level. Particularly for bio-based commodity chemicals, high energy and water use can make process economics unattractive in certain geographies and reduce the 鈥榞reen鈥� benefit.
Schedule:
Abstracts:
The ICM Approach to Efficient Water and Energy Use
Douglas B. Rivers, ICM
The biochemical conversion of grain and cellulosic feedstocks is both water and energy intensive. All ICM designed corn ethanol plants are zero process water discharge plants. Process water is recycled with or without treatment in UASB reactors, depending on the individual plant operation. The only water leaving an ICM designed plant is non-contact evaporative water and water contained in animal feed products. ICM鈥檚 cellulose technology is also designed to a zero process water discharge plant. In a typical cellulose conversion process, there is no co-product to absorb process water. This requires innovative approaches, including co-locating with another commercial plant and more complex water clean-up and recycle strategies.
ICM has also been a leader in dry mill energy use. Historically, ICM plants have used less energy per gallon of ethanol produced than other technology providers. To achieve ongoing improvements in energy efficiency, ICM has aggressively pursued the maximum use of the energy train within the plant. In corn ethanol plants the evaporator train has driven heat/energy requirements. For most cellulosic conversion plants the pretreatment unit operation becomes the high point of the energy train. In addition to maximizing process energy, ICM has also worked closely with equipment providers to identify opportunities to minimize energy consumption, and thus reduce the plant carbon footprint.
Lessons Learned: Development and Scale-up in Aqueous Systems
James J. Grant III, DuPont
The methodology for full scale design of dilute aqueous systems presents a unique set of challenges due to the high latent heat of water. This is particularly challenging when water is the low boiler in the system. This presentation will provide a brief overview of lessons learned while working on the scale-up, heat transfer and equipment design issues in aqueous systems. Topics to be covered include scale-up methodology, aerobic fermentation heat transfer and evaporation of water.
Process and Economic Challenges of High Water Use Processes in Emerging Biological, Renewable and Environmental Technologies
John Ellersick, Oasys Water
Processes with high water usage, concentrations, and/or discharges present significant development and scale-up challenges from process, operations, and economic perspectives. Technologies with these characteristics are encountered in many of todays鈥� important emerging energy, environmental and renewable technologies. In this presentation the author discusses common challenges encountered in the commercialization of these types of technologies, and provides strategies to identify issues during early development work, plan for them in the design phase, and address issues that arise during commissioning, startup and operations.
The presentation will focus on learnings from four major development programs covering biologically based processes to produce chemicals and fuels, renewable feedstock based processes to produce chemicals or fuels, and environmental processes to maximize the recovery and reuse of industrially abused waters, while minimizing or eliminating liquid waste discharges (zero liquid discharge or ZLD). Common themes emerge from these programs around best practices to follow, the competing nature of ease of operations with attractive economics, and challenges due to the presence of solids even in the context of high water content.