A learn-as-you-go recycling operation has solved its crushing problems and doubled its production.

Fucinaro Excavating began in 1963 in Omaha, Neb. In 1970, the company did smaller excavating jobs and grading for some city street projects. In the early 1980s, the business grew into doing larger excavating projects in addition to taking on larger city street and state road projects. The company was doing a lot of paving tear-out work, but few landfills would take the excavated rubble.

In 1992, David, Ron and Mike Fucinaro (sons of the original owners) formed Conreco (Concrete Recycling Co.) to dispose of the concrete and asphalt rubble generated by the excavating company. Conreco looked to reduce trucking costs, reduce tipping fees, provide an inner-city source of aggregates, reduce space required at the county landfill and reuse previously disposed raw materials. Today, nearly half of the incoming rubble comes from other contractors, with Fucinaro Excavating hauling in the other half.

"Everybody is charged a tipping fee of $20 per tandem truck load," said Ron. "Fucinaro Excavating is still the largest consumer of material (about half) because we search out projects that have a need for larger quantities of crushed stone."

Learning the hard way "We didn't know anything about crushing," added Dave. "There were no other recyclers in the area to learn from."

The firm set up a semi-permanent recycle yard in Omaha near I-80. The central location was convenient for contractors throughout metro Omaha and Council Bluffs, Iowa. Conreco's business plan called for a mostly mobile, custom crushing company. Conreco purchased an all-in-one plant design to minimize start-up costs.

"What looked great in the beginning, was not the best long-term solution in terms of production ability and wear costs per ton of material produced," Dave said. "We thought the single impact crusher, with the high reduction ratios attainable, would satisfy our needs.

"To minimize wear costs, we kept trying harder blow bar metallurgy, increasing the chrome content. While the higher chrome makes for less abrasion wear, it also makes the bar more brittle and susceptible to breakage if the feed size is too large. Most everything the contractors brought in was too big to allow for the use of the hardest bars. We broke a lot of bars."

Compounding its problems was the high wear costs per ton of material produced. The company was flipping or changing bars about once a week and getting only about 12,000 tons per set of bars. It also had the problem of oversize pieces getting stuck before reaching the crushing chamber. Conreco then added a Kubota KX-71 mini excavator with a U-B hydraulic breaker installed on a permanent pedestal next to the crusher feed hopper.

"Another problem was the main undercrusher belt conveyor," Mike said. "With all the rebar and wire in our feed material, we were tearing or puncturing the belt almost daily. Our belts were only lasting about two months."

"Also, we started using the grizzly to screen out some fines before entry into the impactor, but it doesn't work good in the wet weather," Dave said. "The mud plugs the grizzly bars and requires a lot of labor and downtime."

These problems might allow for a decent peak tph production, but make for low daily and weekly production.

"As the business grew and the market for recycled products increased, our overall production rates became more and more inadequate," Dave said.

In 1996 the company added a small secondary fine-jaw crusher to crush the oversize return load from the impactor, enabling it to open up the gap setting. This was economically viable, increasing production by about 20%. However, there was still transfer point plugging, blow bar breakage and discharge conveyor belt punctures.

In 1998 Conreco began a year-long research project to design a plant that would meet its annual tonnage objectives.

Finding the solution Kolberg-Pioneer recommended putting a Pioneer 2854 jaw with wide peak-to-peak and deep peak-to-valley jaw dies in front of the impactor Conreco already owned. This configuration tolerates the large slabby materials and eliminates the plugging encountered with the impactor-only layout. Because the jaw is a compression style crusher, the wear costs on jaw manganese is minimal when compared with blow bar wear on a horizontal-shaft impactor used as a primary crusher.

The Kolberg-Pioneer plant design was modified to include a side-discharge vibrating pan feeder under the jaw. Rebar exiting the jaw drops onto the vibrating pan and is transferred to the main discharge conveyor belt where it is captured by a magnet.

After nearly a year of operation, there has been no damage to the main discharge conveyor belt from rebar punctures or tears. The manufacturer also extended the grizzly cross conveyor. This helped control spillage when feeding a fines by-pass stacking conveyor without the need for additional modifications or chutes.

The 2854 jaw plant design incorporates a 50-in. Yen 20-ft vibrating feeder with a 6-ft grizzly section that separates fines and dirt contamination prior to the crushing cycle. The extended side-discharge cross conveyor under the grizzly moves this material to a separate stockpile for sale as miscellaneous fill material.

A standard bolt-on barrel protector plate keeps large slabby materials from damaging the jaw's pitman. The crusher has an all-welded base to increase strength, a saddle block bearing designed for maximum pitman support and reduced overall travel and feed height. Proper nip angles and length-to-gap ratios also are maintained for increased crushing efficiency.

Tons per year double It is now common for Conreco to fill a 20-cu-yd dumpster with rebar or wire mesh in one day's crushing. Material exiting the jaw is passed over a heavy duty screen with 3-in. punch plate. About 50% passes and is ready for the sell pile as either 3 in. screened or 1 in. crusher run product. The remaining material is sized at 8 Yen 3 in.

"A big benefit of the primary jaw placement is that we are now able to control the top size feed into the impactor which lets us fine tune the entire plant's output," Ron said. "Having a consistent feed material enabled us to fit the impactor with extremely hard blow bars to reduce wear costs and maintenance time.

"We increased production from about 600 tpd with the primary impactor only plant to about 1,200 tpd with the big jaw and impactor combination. Our blow bars now last two to three weeks per side. The manganese jaw dies in the 2854 look like they will last about two years.

"We've significantly lowered our operating costs while doubling our overall output. Where we previously used a 4-cu-yd loader, we're now pushing a 7-cu-yd loader. Our goal was not tons per hour for any peak period, but overall consistent production day-in and day-out. We never want our customers to pull up to an empty yard."

"We have diverted over a million tons of broken concrete from the local landfills and illegal dumping areas," Dave said. "We help area contractors reduce their disposal costs and give them a way to dispose of the rubble. At the same time, we can supply them with a consistent, clean aggregate material about 15% less expensive than virgin aggregate. Trucks that must remove the old material from a construction site can now return to the same site fully loaded with recycled aggregate."