by Keith Loria

When Ashlee Yoder was hired as sustainability manager with Salt Lake County Solid Waste Management, Salt Lake City, Utah, earlier this year, its composting operation had been using shredders that were more than six years old, and she realized that many needed to be replaced.

“The thought behind using [slow speed] shredders in the first place was that the feed stock tended to be contaminated with various materials, so [slow speed] shredders are much more tolerant of contamination than high speed grinders,” she said. “We chose the Lindner Urraco 75D mobile shredder, which was brought in to work on our greenway and composting operation.”

That model was chosen because Yoder wanted a higher quality shredder with more features than what the plant was used to. These features included a dual shaft and slow speed shredder that was reversible and an auto reverse fan on the radiator and other air filters.

“I wanted something that would allow us a little more flexibility, so I wrote the specs and the features I was looking for — dual shaft and things like that — and then I received a proposal for this Lindner machine along with a [high speed tub] grinder,” she said. “At the time, I thought that we did need to move toward grinding so the shredder may be a step toward that, and this was a way to get two machines in one.”

Specs she desired in the high speed tub grinder included: being diesel powered, needing a trailer chassis for mobility, a variable size adjustment to control the size of the output; plus an auto shut down, a remote control, micromesh radiator prescreen and a sealed engine compartment.

The Salt Lake County plant takes in approximately 44,000 tons of green waste every year, and the Lindner Urraco 75D mobile shredder is able to process up to 40,000 tons per hour.

“It’s mainly yard trimmings and we do have some food waste that comes in, but we tend not to put that in because it gums up the machines — we can, but we would do it in small quantities,” Yoder said. “[The waste is] coming from curbside collection programs, and curbside collection programs have a high percentage of contamination, so we have crews on the ground that decontaminate the material. The purpose of having the shredder is to tolerate the contaminate that we don’t, or aren’t able to remove.”

Up and Running

The plant took delivery of the Lindner Urraco 75D mobile shredder in June, and it was up about six weeks later.

“With hauling in everything and then the auto lube system had to be installed after it got here, and then the manufacturer sent a trainer out to train, and commission the machine to set it up to operate, it took some time,” Yoder said. “All our operators were trained, so by the time we got all that done, and put it in service, it was about the second week of July.”

She was impressed how the trainer that Lindner sent out knew the machine inside and out and could answer any and all questions.

“It was great to have that knowledge base and all the guys just basically stand around and he tells them, ‘you use this setting for this, and you use that setting for that,’ and show them everything from startup to shutdown, and how to read the gauges,” she said. “This has a touch screen, which is a little different. Our guys haven’t used a shredder with a touch screen, and it’s a pretty dusty environment, so electronics can get messed up pretty quickly on there.”

This is not a problem, however as Linder mobile shredders are made to work in dusty, dirty environments

Each of the operators at the plant had the chance to run it, and the trainer remained for two days while they worked out the kinks.

One challenge that was overcome concerned the remote control. It was discovered that the remote had a distance limitation so operators had to learn not to get too far from the machine.

“We mainly have to just watch the settings. We did have one issue of the belt tracking, so we always have to be vigilant about the pre-check and post check,” she said. “If that belt tracking gets off, it can shred that belt in fairly quick order, and those things are really expensive.”

Service Matters

Another requirement Yoder wanted when looking for the new piece of equipment was that the company supplying the shredder had to close enough to provide service as well. Yoder said the folks at Holland Equipment of Salt Lake City were trained in both the operation of the equipment and the repair service of it.

“I think sometimes that might be an afterthought for manufacturers, but for sure it’s not an afterthought for the purchasers,” she said. “The vendors may not realize how important that truly is.”

As part of the agreement, Salt Lake County Solid Waste Management mandated that the vendor would keep consumable products available and that common repairs would be completed within two weeks.

“There has been really great support from both the manufacturer and their representative, and from the vendor that sold it to us,” Yoder said. “Both of those people and organizations have been very responsive, and they come out almost immediately if we have any issues. But we also have fleet support here, on the facility. It needs to be lubed every day, so our regular fleet people will do that. They will check the hour meter and when just regular service stuff comes up then they’ll take care of the small things, and then our vendor will take care of any of the larger preventative maintenance things.”

The plant doesn’t need to worry about too much cleaning Yoder noted, as one of the benefits of shredders is they don’t hold a lot of material in their chamber and its speed is slow, so it doesn’t create friction or a fire hazard, as long as the chamber is empty.

Final Thoughts

Now that the shredder has been up and operational for a couple of months, Yoder is very pleased with the decision to go with the Lindner Urraco 75D mobile shredder, especially since it was married with the high speed grinder in the deal.

“We have that [slow speed] shredder actually feeding a [high speed tub] grinder, and it’s working out really well because we’re getting the size reduction that we want, and we’re able to do that without damaging the machine due to contamination,” she said. “Our experience has been generally positive. I think the benefits are, it’s not difficult to run, it’s pretty heavy duty, it’s been pretty low maintenance, and it’s not expensive to maintain.”