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Central C&D Recycling, Des Moines, Iowa, gets its products clean so it can demand top dollar.

William Turley May 22, 2001

Central C&D Recycling is a believer in a variation of the computer term “garbage in, garbage out.” If any garbage is part of the infeed to the recycling plant, then it must come out of the final products.

Granted, a lot of C&D recyclers try to do the same. But after being in the C&D recycling business for six years, Central is obsessed with it, because management feels it is the key to success in marketing its many products.

“That is what separates us from other C&D recyclers,” says Robert C. Hosier, vice president. “We make a concerted effort to pull out the trash by making a positive pick for it. Then what you have left over are commodities that can be sold.”

To that end, the company recently opened its new facility in Des Moines, Iowa, designed specifically to produce clean products. At the site, Central C&D makes products from, or separates for further processing into products, asphalt shingles, concrete and asphalt, gypsum, metals, old corrugated containers (OCC), and wood. In fact, the company makes two levels of wood products, including infeed for a nearby particleboard plant making furniture.

The Central C&D plant boasts a 90% recycling rate at 50 tons per hour, and makes no alternative daily cover and little cogeneration fuel. “We have an account to sell boiler fuel, but it is such a low price with a small net, we only sell them our leftovers,” Hosier says. That’s easy to say when you get $40 per ton for your premium wood chips and $15 to $20 for your animal bedding, such as Central does.


Central began recycling mixed C&D in 1995 in an attempt to save space at a rapidly filling C&D landfill it owned. The company is related to Corell Contracting, which owned/s a concrete/asphalt recycling company.

Because they were new to recycling mixed C&D, Hosier says the company relied on the advice of others in the design of its first plant, which was a simple trommel screen followed by a picking station. Hosier calls it their “trainer plant.”

“This is how we were told it was done,” says Hosier, “You pull it off the picking line, throw it into boxes, and whatever falls off the end goes to the landfill. But we found that doesn't give you a lot of recovery, it doesn’t make you a whole lot of money, it doesn't do a whole lot of anything.”

He discovered that when he went to sell his finished products from the first plant. “We sold some, but the biggest complaint we heard was, ‘You have plastic in it.’ That meant the customer wasn’t always happy and wouldn’t always buy, and Central received a much lower price for its goods.

The company’s philosophy always was that it would use its competitive tipping fee it received to subsidize processing operations, and profits would come from product sales. Hence, profits were suffering. A new plan of attack was needed.

Hosier, along with company president Steve Corell, decided to develop a new plant to make the products they wanted to sell. They had landed the contract for the particleboard plant, and had to make sure they could produce a clean enough product for that application, as well as for its other markets. “We knew we had to step to another level with the new plant,” says Corell.


Hosier says the first step they did, and what anyone should do who wants to get into the business, is to “go to the finish line first, and then figure out how to get to the finish line. Look at your markets first, see what’s there, then back yourself out to what you have to work with as infeed. Then worry about getting your equipment.”

What they determined was a need for next to godliness. Hosier says the company sat down with the potential equipment suppliers separately and told them, “One thing you are going to take out of this conversation is that we don’t want the trash. I don’t care if we miss a little wood or concrete. We need the trash out. As soon as we have the trash in there, then we are selling trash.”

Hosier and Corell settled on a combination starscreen/air separation/picking station/float tank system. Here’s how the system works at the 50-acre site.

First incoming trucks are weighed and the drivers interviewed about their truck contents. Clean gypsum, brush, and asphalt shingle waste are directed toward separate areas for processing. The rest is dumped in a corrugated metal building with a concrete floor (10 acres are paved with concrete), several doors and a ceiling high enough for all trucks to tip within.

The material is inspected and some minor presorting done. Then a wheel loader pushes it in place to be fed into the sorting system. More presorting is performed, concentrating on the plastics, especially the long sheets. Big pieces of concrete, wood, and steel are set aside because “you don't want to drop 200 pounds of concrete on the transfer points in the system,” Hosier says.

A wheel loader feeds the sorting system, the majority of which is from Lubo USA, Stamford, Conn. A four feet, seven inches by 19 feet, eight inches vibrating feeder starts the material up a nearly five-feet-wide belt to the first sorting platform, manned by two of the best pickers at the plant. They remove large bulky items, such as carpet and long, stringy items that won't go through the starscreen.

The starscreen is the same length and two inches wider than the vibrating feeder. The star diameter is two feet, two inches and the stars are arranged in a pattern that allows 18 inches or so fall through space. The actual setting varies from day to day and is easily adjustable. Overs from the screen proceed to an 85-feet-long sorting conveyor for further picking for “A” (better quality) wood, metals, cardboard, and then the trash toward the end. Aggregate is left on the line.

The unders from the first starscreen fall onto a conveyor making a 90 degree turn, and then the material takes another 90 degree turn into a second starscreen that screens out the 3/8-inch minus. The star diameter is 6.4 inches. The fines are sent to a separate pile and later sold as a non-structural fill for about $2 per ton. The overs go to a second picking line 61-1/2 feet long by 3 feet, 3 inches wide. Between the picking line and the second starscreen is an air separation system that removes the light fraction, such as small pieces of plastic and is integral to the cleanliness of the final product. A magnet also is on the secondary picking line.

Both picking lines are enclosed, and the secondary line feeds into a float tank made by Flo-Cait, Holland, Mich., to separate the wood from the aggregate. The wood is sent to the proper pile for later processing. There are two sizes of aggregate, small and large fraction. The small is used as-is as choke rock for temporary roads. The larger fraction is mostly sent to Corell Recycling, Steve Corell’s concrete and asphalt recycling operation at another site.

The air system is key to getting things clean, he says. “It gets a lot of the plastics, cuts down on labor costs, and gets us a higher end product we can get more money for.”

There are 12 pickers on the line at the plant, 10 in the picking house and the two pre-sorters before the starscreens. Two loader operators move infeed and product around. Other personnel include a scale house person, and one person on presort before feeding into the system. Currently the plant is operating six days a week, two shifts.


What those workers are making is a wide variety of products besides the extra-clean wood. Gypsum is processed and mixed along with clean wood to make an animal bedding product that farmers love, Hosier says. “The dairy guys like it because the drywall soaks up the urine from the cows, and there’s a lot of nutrients in that. They sell it to the composters.” Contaminants in the gypsum have not been a problem, he adds.

The wood is made into chips with twin 300 horsepower electric grinders made by Terex Recycling, Myerstown, Pa. The chips must meet a tight spec for the particleboard manufacturer, he says, and must have the correct percentage of long pieces and fines to work in the finicky particleboard plant. Central C&D is the sole supplier on the contract, a decision of the customer.

Asphalt shingles are ground by a Beast model machine made by Bandit Industries Inc., Remus, Mich., for several applications. Most are put down on gravel roads as a dust suppressant. There has been some headway with a local asphalt plant for use in their mixes, but they already have a large amount of their own recycled asphalt pavement to use, so shingle use is not high on their priority list.

Metals and OCC markets are about the same as everywhere else, meaning they are down. But it is just another chance to divert more from the landfill. Even so, Hosier estimates the baler used on OCC should be paid off within a year.

These are all markets developed since the company began recycling mixed C&D six years ago. The sales of the recycled products are key to profitability, he says.

“People in the industry come in, look at our plant, and say it looks good, you are doing it right, but they don't know the blood, sweat, and tears that went behind getting this far,” he says, who is a member of the Construction Materials Recycling Association's Board of Directors.

“This may look simple, but it is going to be very difficult for someone to jump in, write a check for $1.5 million and hand it to a salesman, and expect to make it work. They better be ready for a heck of a ride.”

A major part of that ride is the development of markets. The cleanliness issue was just one hurdle Central C&D had to overcome to find places for its products. Some potential buyers did not see a need to switch to recycled. In those


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