The Consolidated Precision Products (CPP) Minneapolis operation is one of eight CPP facilities in the U.S. and Europe. CPP Minneapolis uses chemically-bonded sand to cast a variety of aluminum and magnesium alloys in parts up to 1,000 pounds for critical aerospace applications.
MnTAP placed an intern at CPP in 2008 to research alternatives to the use of the potent greenhouse gas sulfur hexafluoride (SF6), which is used as a cover gas in magnesium casting operations. Molten magnesium easily reacts with air and burns vigorously during melting and pouring procedures without the use of a cover gas to isolate the metal. CPP wanted an intern to research SF6 alternatives in part due to the Environmental Protection Agency and International Magnesium Association 2003 Emission Reduction Partnership commitment to eliminate SF6 emissions by the end of 2010.
Based on the intern’s research, an alternative substitution of a low concentration of sulfur dioxide (SO2), historically used in the industry at high concentrations, has been successfully applied in most of the magnesium casting process. The investment in mixing and application equipment has been substantial, and has since included a mechanical rework of the magnesium casting area to add new ventilation hoods, ducting, and equipment. Currently, the facility has reduced the annual use of SF6 by 36,500 pounds and is saving over $250,000 annually.
CPP hosted another MnTAP intern in 2010 to work on a number of energy efficiency improvement projects, including the design and implementation of the aluminum. A number of recommendations were made by the intern in process areas where the facility was facing air quality challenges. At least half of the recommendations have been implemented and additional improvements are continuing to occur since the intern was hired as a full-time CPP employee. To date, CPP has documented annual energy use reductions of nearly 1 million kWh and 93,000 therms and is saving nearly $120,000 annually in energy costs. An additional ventilation redesign project is nearly complete and is expected to reduce annual energy use by 786,000 kWh and 6,400 therms.
What they said...
“The beauty of it is (the intern) is focused on one thing.”
-- Jim Trudeau, Facilities & Maintenance Manager at CPP
Jim Trudeau, the facilities and maintenance manager, served as the on-site supervisor for both interns. He reported that the SF6 project helped spur the entire corporation to move toward eliminating the use of SF6 as the primary cover gas at all three of the CPP magnesium casting facilities in the U.S. The Minneapolis facility has not purchased any SF6 since October 2011 and expects to use 90% less in 2012.
Like our content and want to share it with others? Please see our reprint policy.