Kraemer Mining and Materials Restructures Plant Design at its Burnsville, Minn., Quarry.
By Mark S. Kuhar
Kraemer Mining and Materials lies right outside of the Minneapolis-St. Paul metro area in Burnsville, Minn., adjacent to I-35 and the Minnesota River. In operation since 1959, the 500-acre limestone quarry produces dry screened and crushed rock in addition to a plethora of washed products.
One of the few limestone producers in the area, Kraemer has provided material for a number of high-profile projects throughout the years, including the construction of the Mall of America in 1992 and numerous metro interstate, bridge and airport improvements.
For more than 20 years, Dave Edmunds, executive vice president and chief operating officer of Kraemer, had a vision for the company’s Burnsville quarry. He wanted to see all operations moved to one location on the floor of the pit. In 2014, John Rivisto was hired as vice president and general manager of Kraemer. Edmunds immediately entrusted his vision to Rivisto and handed him the reigns to manage the project.
“We could not continue to mine for 20 or 30 years hauling product up to the rim of the quarry and hauling product back down to the floor of the quarry constantly,” said Rivisto. Plant operators were washing material in two different locations of the quarry and relying heavily on trucks to haul material from spot to spot. It just made no sense. It wasn’t cost effective; it wasn’t environmentally friendly.”
Kraemer needed an all-inclusive plant that would incorporate dry screening, crushing, conveying and washing, all located at the floor of the quarry.
Finding a Project Partner
To pull the project off cost effectively Kraemer, “needed to have a company that would provide design and engineering services, construction services and quality fabrication,” said Rivisto. The company’s options were limited as they tried to find a manufacturer that wouldn’t require them to hire outside engineering services.
Kraemer considered three major vendors for the project including Superior Industries, a manufacturer of bulk material processing and handling equipment. Quarry Superintendent Mike Strom met with Jason Adams, vice president of Systems at Superior. Together, they visited Trap Rock & Granite Quarries south of St. Louis to see a construction project that Superior had completed in January of 2016. Superior had engineered, manufactured, delivered and installed 90 percent of the equipment for the Trap Rock project.
During the trip, Strom was convinced that Superior would be a good company to partner with. “I knew that Superior was the company we needed to work with because they did a good job handling everything and you could tell if there was an issue, they’d get it done fast,” he said.
Adams’ 20-plus years of industry experience helped seal the deal for both Strom and Rivisto. “Jason knew exactly what we needed to do,” said Strom.
“We had a fairly long history with Superior,” said Rivisto. “We wanted to work with a company that one, we had a history with, two, we felt very confident that they’d be able to meet our needs, both in the quality, the design, field service and certainly quality of fabrication and the schedule.”
Edmunds and Rivisto laid out a timeline for the project, scheduling installation from late October 2016 with a completion goal of mid-March 2017. Pre-install preparation would be necessary in order to complete the required fabrication during those five months set aside for the project.
Superior and Kraemer worked together through the summer and fall months to complete the conceptual drawings, concept of operations and electrical plans. By the time Kraemer’s crew unplugged in October, the foundations were set for a successful project. Rivisto recalled, “Superior had folks on site, we had our concrete contractors in, we had all that engineering done ahead of time and pieces started going up in November.”
Equipment Installation Underway
One of the biggest challenges of the project was beating the cold winter weather. Rivisto commented that five months during a Minnesota winter can quickly become three or four months of available working days. “The contractors and the fabrication delivery, that’s manageable, but weather is weather and you have to deal with it up here in Minnesota,” he said.
Thankfully, a long fall season allowed the project to move ahead of schedule before winter hit. Superior installed 20 new conveyors into Kraemer’s plant, integrating them with crushing, screening and washing equipment from other vendors. Back in 1997, Kraemer purchased the first-ever Telestacker Conveyor, Superior’s flagship product. “It’s still operating, still runs like a champ,” commented Rivisto. For the new plant, Kraemer added two more Telestacker Conveyors and four radial stacking conveyors.
“Superior came up with some really interesting ways to convey material,” said Rivisto. The design incorporated several splitters and diverters, giving Kraemer extra flexibility in moving material from one side of the plant to the other. A large surge tunnel was also added to the floor of the quarry to feed a screened product to the wash plant, allowing Kraemer’s second shift crew to operate later into the evening.
By March 15, 2017, the project was substantially complete. The crew started bumping motors and adjusting the new equipment – getting the flow of material just right. The 1,000-tph capacity plant was finally on the bottom of the quarry floor with the dry and wash sides sitting opposite of each other.
“We took a couple weeks longer than we hoped for, just to work all the bugs out,” Rivisto said, “But, to pull this off in such a short period of time was really a testimony to several things. One, Superior certainly gets a big pat on the back. Other vendors do as well. They all came together, everybody worked together with us as the general contractor.”
Being a Good Neighbor
In order to maintain good relationships with the city of Burnsville and nearby neighbors, Kraemer made sure to move a mass of old iron within eyesight of the interstate down to the quarry floor. Running a plant in a highly populated area can be tricky business. Noise and dust generated at quarries are often cause for concern to surrounding communities. “Most of our neighbors don’t even know we exist here and we take a lot of pride in that,” said Rivisto.
Kraemer has an agreed-upon, long-term use development plan with the city of Burnsville. The agreement includes permission for Kraemer to mine further west in the quarry, allowing the company to tap into 30 more years of material reserves. Kraemer’s partnership with Superior to restructure the design of the plant will enable the company to continue mining over the next few decades in a more energy-efficient manner.
“Sixty years ago, they put the first shovel in the ground in Burnsville, a company from Plain, Wis., called Edward Kraemer and Sons. Now, in 2017 we have a state-of-the-art limestone processing plant that will be very cost effective for 20 or 30 more years,” said Rivisto.
Information for this article courtesy of Superior Industries.