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By Greg Northcutt
The need for more speed and more efficiency, not to mention tightening air-quality regulations and rising dumping fees, is fueling the growing demand for alternatives to traditional practices of disposing of debris generated by land clearing work. At one time, preparing a site for grading and excavating work often meant tearing out the trees and brush, pushing it in a pile, and lighting a match. That way of doing business is quickly fading. “It’s getting to the point where you can’t burn it and the landfills don’t want it,” says Bill Gehoski, regional sales manager for Bandit Industries Inc. in Remus, MI, which manufactures machines for shearing, chipping, and grinding trees and stumps.
In many areas, regulations to protect air quality from smoke and soot prohibit or severely restrict burning of cleared trees and brush. Even where allowed, the threat of wildfires in drought-stricken areas can put a damper on this approach. Where burning is not an option, high and rising trucking costs and tipping fees make a trip to the landfill increasingly unattractive—that is, if the landfill will even accept the material. As space gets tighter, more and more landfills are turning away loads of organic material like logs and limbs. It’s a similar story with rock, concrete, and asphalt and other construction and demolition materials. It’s becoming increasingly more expensive to dispose of them offsite. As a result, grading and excavation contractors are turning to faster, more efficient ways of dealing with debris. They’re grinding trees and stumps and crushing rock and asphalt to recycle this trash into materials that can be left or reused onsite or sold for other purposes. Buying their own waste reduction equipment gives them more control over their recycling costs and scheduling. It also gives them an edge over other grading and excavation contractors who rely on subcontractors to do the work. In fact, some are using this equipment to boost revenue by adding their own grinding services. A Growing Trend “Back then we were ahead of the times,” he says. “No one wanted to spend money on a machine to grind up trees when they could just push them in a pile and burn them. It was the cheapest way to dispose of them.” That situation began to change about 10 years ago as enforcement of air-quality rules picked up and landfills began filling up. “Grading and excavating contractors who wouldn’t talk to us about our equipment in the past are now calling us,” Bennington says. “I expect to see tremendous growth in this type of equipment in the next 10 years.” The increasing demand for site clearing machines reflects a healthy construction market, adds Randy Dodd, director of sales and marketing for Diamond Z Manufacturing in Caldwell, ID. “The building industry has been very active in the last several years, and builders have to clear land and dispose of debris,” he says. Some of the material that comes out of grinders is left onsite to help control erosion until it eventually biodegrades. Much of it is sold. “Some grinding contractors do primary grinding, selling the material to others who grind it smaller to make mulch,” says Dodd. “Others do it all and bag the end product or sell it by the truckload.” To add even more value to mulch, grinders can be equipped with devices that meter out coloring pigment to produce decorative mulch in various earth tones. Typically, it costs about $3 to $5 per cubic yard to grind greenwaste into mulch that may sell for $10 to $25 per cubic yard depending on locality, reports Gehoski. Another market for ground-up trees and stumps is for boiler fuel. For example, Bennington reports that at least one city in Ohio burns the material in the winter to generate steam for heating several downtown buildings and helping provide electricity. Many Choices
In the case of a tub grinder, the logs and limbs are cut to length to fit into the tub, which rotates to grind the wood. With a horizontal grinder, the entire length of a tree can be fed into the machine without cutting or shearing into smaller pieces. A top roller and a bottom conveyor chain draw the tree into the milling area. With either style, a choice of screens determines the size of the output and a conveyor belt is used to dump the material in a pile or load it into a truck. Manufacturers of grinders offer a wide array of models. Tub grinders are available with tubs ranging in size from about 8 to 14 feet in diameter. The openings of horizontal grinders may measure as large as 5.5 feet wide and nearly 4 feet high. The highest-production units can weigh over 100,000 pounds and reduce upwards of about 500 cubic yards of logs and stumps in an hour. Ten years ago, tub grinders accounted for about 95% of industry sales, Gehoski says. Today, he estimates, they represent about 20% of total units sold.
The majority of tub and horizontal grinders are wheel units. However, the more expensive self-propelled, remote-controlled track machines are growing in popularity. “Unlike a grinder on wheels, tracks enable you to go where you want year-round,” says Gehoski. “And more, it seems, contractors are being pushed to work every day possible because of tight deadlines. If the schedule calls to begin moving dirt on February 15 and you can’t get in there with your wheel grinders to start clearing operations until a month later, you’ve got a problem. Track grinders eliminate that problem.” They eliminate other problems as well, adds Tim Wenger with CW Mill Equipment Co. Inc. in Sabetha, KS, which makes Hogzilla tub and horizontal grinders. There’s no need to bring in a truck or dozer to move a track grinder around the job site. Also, there’s no need to build roads to reach the work area. “You can take off across country and not be too concerned about crossing creeks,” he says. “A track machine can save you a lot of time and labor. Instead of building roads, which you don’t get paid for, you can spend your time and labor making money by clearing the land.” On the other hand, a towable grinder can be wheeled down the road, while a track unit has to be loaded and hauled on a trailer. Surveying the Market
Enclosed Tub Grinders The 85,000-pound E6000B, with an 11-foot-diameter tub, is powered by an 800- to 1,000-horsepower Caterpillar engine. It has a production rate of up to 70 tons or 210 cubic yards of stumps and logs per hour. The E4800B features a 550- to 650-horsepower Caterpillar engine and an hourly production rate with stumps and logs of up to 45 tons or 135 cubic yards. This 62,000-pound unit has an 8.5-foot-diameter tub. Both models can handle material up to 8 feet in length. More information is available at www.diamondz.com. More Efficient Tub Grinding
Another unique feature of the TC Series is the patented adjustable swing hammer mill. “It gives operators a choice of three swing diameters to vary the depth of cut and feed rate,” Wenger says. “This improves and refines the aggressiveness and productivity of the machine to match each job.” The TC Series models range in size from 86,000 pounds to more than 110,000 pounds with a choice of 750 to 1,650 horsepower Cat, Cummins, or Detroit engines. The standard 15-foot-diameter tub has a transport width of 11 feet, 11 inches. More information is available at www.hogzilla.com. An Alternative to Hammer Mills
The design of the cuttermill limits the bite of the cutting, splitting, or grinding tool to control size of the product and maximize engine horsepower, he explains. The result is more efficient operation. “Tub grinders rotate at 2,000 revolutions per minute,” Gehoski says. “By contrast, the cuttermill operates at just 600 revolutions per minute. That means lower fuel and maintenance cost, smoother operation, and longer life.” The four models of Beast Recyclers are available in sizes from 39,000 to 95,000 pounds with 275- to 1,000-horsepower engines. More information is available at www.banditchippers.com. More Options
The Sneller Multi-Task 190 carrier, a track excavator with a special boom and arm, can be equipped with five Sneller attachments—a 275-horsepower self-powered, non-hydraulic shredder for clearing heavy brush and trees; a shear to cut down trees; a saw to cut trees into logs; a 360-degree grapple to sort and load logs; and the self-powered 275 Stump Mill for grinding stumps. These attachments can also be mounted on various makes of excavators. The Multi-Task 190 is designed to eliminate the need for separate machines to accomplish these tasks. “It can save up to half the cost of buying each individual type of machine,” says Bennington. The 275 Stump Mill is powered by a 275-horsepower diesel engine. “The unit’s direct-drive system provides more cutting torque as engine speed drops under a load, compared to hydraulically driven machines, which have less torque and a very flat torque curve,” he says. It also features carbide-faced cutting teeth with a negative rake for longer life, he adds. More information is available at www.snellermachine.com. Greg Northcutt writes frequently on construction and business issues.
GEC - May/June 2006 |
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PHOTO: DIAMOND Z 
