Demolition Recycling

Universal Wrecking uses crushing system to provide full service to customers
Universal Wrecking Corp. (UWC) is a national demolition, wrecking and recycling company that has crushed and recycled more than 50,000 tons of concrete and masonry materials in the past year.

By Damon Kozul

Universal Wrecking Corp. (UWC) is a national demolition, wrecking and recycling company that has crushed and recycled more than 50,000 tons of concrete and masonry materials in the past year. This is part of UWC’s constant efforts to recycle as much materials as possible on each building and facility demolition project. These wrecking projects generate significant quantities of demolished materials including wood, concrete, brick, masonry, steel and other materials. Wood timbers and beams, when possible, are salvaged and sent to reuse companies that take the salvaged beams and turn them into wood flooring or other architectural products. Steel and metals are sent to scrap metal recyclers. Concrete, masonry and brick are crushed and either sent offsite for recycling or re-used onsite as backfill.
When crushing of aggregate materials is needed, UWC transports a track-mounted crusher to the site that can be easily repositioned onsite as needed. In order to crush and recycle the concrete, brick and masonry materials, UWC uses a Pioneer FT4240S impact crusher. This mobile, closed circuit, impact crusher has a 42- x 40-in. feed opening, a 4-ft-long grizzly feeder and weighs 94,000 lb. High-chrome bars currently are used as blow bars, but the company is evaluating other materials for the job.

The crushing unit has a magnet to remove metals (typically rebar) that is placed in separate containers for offsite processing. A conveyor scale keeps track of the quantity of daily crushed materials. When crushing large quantities of materials, UWC will also use radial stacker conveyors 40 to 80 ft in length to facilitate stockpiling activities. Dust is controlled with a spray bar on the crusher, but sometimes a fire hose is used for dustier applications.   

To meet crushing specifications, the size of the crushed aggregate as well as the cleanliness of the materials are carefully separated to be crushed from debris and metals. Typically an excavator with a grapple, skid steer with demolition bucket, and a front end loader are used to sort the materials. Hand labor is also used at times to ensure the pre-crushed material pile is as clean as possible prior to crushing. When concrete from foundations, footings and piers require crushing, an excavator with a universal processor or hammer attachment is used to pre-size the materials. A Caterpillar 345B excavator with a 3-yard bucket feeds the crusher.

“We like to load with an excavator so that we can control the feed materials as well as not having materials bounce, fall or hit the side of the crushing machine,” said Steven Vesseli, business development manager, UWC. The material is sized down using various demolition attachments before feeding into the crusher. “We like to size materials to 2 ft minus as we experience better production rates. We feel it keeps down the wear and tear on the crushing unit.”

Crushed materials that include concrete, masonry and brick are processed in the crushing machine to 1½ inch minus material. A 6 x 16-ft double-deck KPI screen is used to size the material. Depending on the materials, daily throughputs range from 600 to 1,200 tons per day.

This material is suitable for use as backfill and has good compaction properties. A vast majority of clients use this material as backfill instead of importing offsite backfill materials. This saves significant amounts of money. It is also a very environmentally friendly practice and can be an integral part of an overall LEED program. Based on the 50,000 to 100,000 tons of crushed materials UWC crushes in year, it made sense for UWC to purchase its own crusher for the work. “We found it was cheaper to purchase then continue to subcontract or rent the equipment. We also like to provide complete turnkey operations to our clients,” said Vesseli. “We typically make general backfill spec materials on our projects, which is 2 inch minus. We have backfilled using this crushed material on many of our projects saving clients a significant amount of money versus importing offsite materials.”

This is also a “green” use of the material versus sending offsite to a landfill or trucking offsite (using fossil fuels) to a recycler. UWC seeks to continue its “green” practices in 2010 and has several demolition projects currently under way where significant recycling will be conducted.

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