Looking first at the entire process. How did a bioprocessing firm that uses soy meal in a fermentation system to produce an enzyme achieve a technically sound and cost-effective climate control system? It combined a thorough needs and site assessment with the transfer of knowledge from the food industry. Although the end-product of this process is not used for human food production, bioprocess engineers with SSOE Group designed the storage environment as if its contents were intended for human consumption. Going this extra mile reflected SSOE’s respect for the potential negative impact of contaminating a batch of expensive product.
In this case, the soy meal was received in bulk and stored in a bin. Although it was not especially sensitive to degradation, humidity and the resultant clumping were still problematic. The conventional solution? A cooling coil and reheat coil system, or a desiccant system. However, because this manufacturer used dry nitrogen in other parts of its process, the SSOE engineers designed a dry nitrogen purge system to control humidity within the ideal range. The capital outlay for this innovation was one-third that of the conventional cooling or drying technology.
Using small containers and off-the-shelf equipment for an offshore pilot plant. Practical and economic constraints created challenges for SSOE process engineers when asked to design a raw material storage and handling system for a biofuel pilot plant at an offshore location. Both the equipment for the plant and the raw materials were to be delivered by container ships. The engineers’ solution enabled the owner to use bulk bags, totes and drums, and it incorporated off-the-shelf equipment to handle dumping, pumping out, emptying and hanging these containers.
It was elegant simplicity. Bulk bags arrived by ship; fork trucks unloaded and delivered bulk bags to the storage and handling area; the bags were hung on an emptying station; contents were emptied into a conveying system; and raw materials were conveyed to a slurry-mixing tank. In addition to handling the raw material, the solution minimized capital cost, achieved cleanability and optimized efficiency. There is no master specification for such equipment. Because this was a pilot plant, the engineers also maximized its flexibility to safely process new and possibly more corrosive materials in the future.
Pre-fabricate to reduce cost, accelerate schedule and improve QC. Another manufacturer had to double its plant capacity, including raw material storage, to keep pace with forecasted market trends. With the plant remaining in operation, SSOE completed the project in 11 months. To do this, the engineering firm partnered with two contractors to execute a design-build plan that used prefabricated components. While one contractor worked on slip forms for the silos, the other worked on the conveying system using prefabricated pipe and other components. Tie-ins were made during scheduled process shutdowns. The parallel team approach not only cut 25% off the original construction schedule, it improved QC because shop fabrication allowed greater control conditions.
In the bioprocessing industry, well-designed bulk material storage and handling environment are essential in preventing raw material breakdown, spoilage, exposure to moisture or contamination or pest infestation. The components of such an environment include: a well-designed silo or other storage container system; effective climate control; smooth conveyance of the material in and out of the container; and cleanability for quality assurance and operational efficiency. When innovative thinking is combined with a technically sound design, the result can save bio-processor’s time, trouble and money.
Mark Hoffman, PE, is an engineering manager at SSOE Group (www.ssoe.com). He has more than 30 years of experience in project/engineering management in many industries. Hoffman can be reached at 651-726-7660 or Mark.Hoffman@ssoe.com.
Published in the November 2013 edition of Pharmaceutical Manufacturing