Published in the March 2011 Coal USA Magazine
The Wisconsin facility, with the help of Illinois conveyor supply provider Martin Engineering, now has eliminated material backups, reducing maintenance and extending the life spans of its belts with custom-engineered transfer chutes. Designed and constructed specifically to address flow rates and physical characteristics of the terminal’s coal, the chutes have helped to avoid blockage and minimize fugitive material, reducing costly interruptions to clear plugged sections and clean up spills.
“We load ships around the clock, so it’s difficult to find time to make changes to our system,” terminal operations director Marshall Elder explained.
“We cannot keep vessels – and our customers – waiting for coal while we make changes to our equipment.”
Martin Engineering designed and constructed the entire chute system offsite, then transported the infrastructure to the facility and had it installed in just four weeks of scheduled downtime.
The 30-year-old Superior Midwest Energy Terminal, on a 200 acre site at the mouth of the St Louis River, processes about 22 million tons of coal each year from the western coalfields, unloading Union Pacific and BNSF trains from the Powder River Basin – about 1400 per year – and transferring them onto vessels for transport to US and Canadian utility power plants. Over time it has become one of the largest coal handling terminals in the world.
“We unload railcars at 5000 tons per hour, roughly 45 cars an hour, or a full 123-car train in about three hours,” Elder said.
The terminal then loads coal onto approximately 450 vessels during a 305-day shipping season; shiploading operations run from late March until mid-January, when ice forces the Wisconsin port to close.
“This is the largest capacity coal terminal having only one single-car railcar dumper – we put more coal through that single-car dumper than any operation in the world,” Midwest Energy Resources president Fred Shusterich noted.
“MERC is a high volume operation, and because of that fact, we make the investments to maintain peak performance levels of our primary coal-handling operations.”
Martin Engineering custom-engineered its Inertial Flow transfer chutes specifically for the Superior Terminal, and since installation they have minimized previous plugging issues.
“When a chute used to plug up, the material would spill onto the floor and around the conveyor idlers,” Elder said.
“And at 11,500 tons per hour, it doesn’t take long to put a large volume of material outside the chute. That’s a lot of spilled coal, and a lot of man-hours to clean it up.”
The terminal is also anticipating it will realize longer belt life from the revamping, and Elder said that is one of the key reasons it opted for engineered chutes.
“We anticipate an increase in belt life of approximately 40%, primarily because of the reduced abrasion realized with the new chute design,” he noted, adding that he expects to get seven to eight years from the major belts – or about 175 to 200Mt of throughput.
Shusterich said the Martin Inertial Flow chutes are giving the terminal a helping hand at maintaining efficient operations and a reliable supply.
“We pride ourselves on the volume of material handled, and on our dependability,” he said.
“We know it’s more than western coal we are delivering – we are providing power to communities, so we need to be consistently available and operating at peak efficiency. The engineered chutes from Martin Engineering help make that possible.”
