Hurricanes along the Gulf Coast, tornados in the Midwest, and other natural disasters present the need for industrial-grade disposal and recycling.

By Marsha DeClue

North Carolina’s location makes it a target for hurricanes and, despite our being about 80 miles inland, we can still be hit hard, as we were by Hurricane Fran in September of 1996,” says Bobby Howard, solid waste director for Cumberland County, NC. “When something like that happens, volumes of debris coming through this site easily triple and can stay at that level for as long as a year. After Fran, we were taking material in to each of our satellite sites, stockpiling it, and then taking the grinder from site to site to process the material. The Morbark grinder really performed well for us, despite the long, long hours to which it was subjected for months on end.”

“Consider the recent devastation caused by Hurricane Katrina,” says Terri Ward, sales and marketing director for SSI Shredding Systems Inc., Wilsonville, OR. “Time and time again, we hear from contractors who are using high-speed grinders to reduce piles of rubble left behind in residential areas, not just separated wood materials. Their grinders are either ‘down’ more than they’re ‘up,’ or repairs are so costly, they can’t earn enough from the job to continue processing.”

According to Aaron Benway, regional sales manager for Continental Biomass Industries Inc., in Newton, NH, grinders and shredders can be used to reduce the size of the material (volume reduction), thus increasing the weight per cubic yard or ton, reducing transportation costs by maximizing the allowable weight per truck or rail car.

“Volume reduction allows for better utilization of airspace at the landfill, more material in the same given area,” says Benway. “Grinding or shredding prior to the material being conveyed to a picking line, with magnets for metal removal, or screening equipment, allows downstream processing techniques to be more effective because of the reduced material size. Also grinding residual material can be done at the end of a processing system to create a specific end-product such as ADC . Clean wood recovered from the incoming material stream can be ground into a boiler fuel product to be utilized at a burn plant to generate power.”

Jerry Morey, marketing manager of Bandit Industries, says he’s seen an increased use of grinders and shredders to deal with all types of waste, not just C&D. “Grinder and shredder use has increased significantly with the enforcement of non-burning laws, rising landfill costs, and the prohibition of the landfilling of any type of organic materials. Grinders or shredders are used to significantly reduce the volume of construction and demolition material. They also can put the debris into a form where it can more easily be recycled,” Morey says.

Gert F. Semler, managing partner of HAMMEL New York LLC, says one of the main reasons to have a grinder or shredder is to reduce the volume (of waste) to half or less. He says there is usually a volume reduction between 2:1 and 3:1. This creates screened-out ADC material, which is taken by the landfills—if not for free—at least for a lot less than the regular C&D debris. “Last but not least,” says Semler, “to get the ferrous metals out with the cross-belt magnet, get paid for scrap and do not pay for the weight at the landfill.”

Shredding C&D means there’s more in your trucks, your boxes, your trailers, and fewer runs to the landfill.

“You can also screen out the [heavy] fines and dump them as ADC for far less,” says Semler. “You can get paid for the [heavy] steel and in return get paid for scrap metals.” It’s a win-win for any waste management operator. Joseph C. Giebelhaus, solid waste manager for the City of Albany, NY, says, “Prior to shredding, we saw densities in the 1,500- to 1,700-pound-per-cubic-yard range—typical for an MSW landfill. In the first year of shredding, we saw our number approach 2,000; now we are at 2,200 average density for the year. Third quarter 2005, we achieved 2,840 pounds per cubic yard.”

Giebelhaus says, “We are looking for the ultimate bioreactor landfill. Taking a page from the yard waste compost community, we believe that volume reduction does more to promote decomposition than leachate recirculation ever would.”

The City of Albany operates a Diamond Z SWG 1600 at its landfill. Giebelhaus says he thought operating at the face of the landfill was a new approach. “We’ve been operating it for a year to shred waste at the working face of the landfill,” he says. “We shred up to 1,000 tons per eight-hour day with this unit. The year prior, we used a Doppstadt to shred roughly 500 tons per day. Both excellent machines.”

One challenge Albany and others face is that of less and less space and available options. “We have limited space in the landfill and limited possible areas to expand,” says Giebelhaus. “Our closure date was late 2007. Now that we are shredding, our closure date has been pushed back to late 2009. In rough terms, for every three months we grind, we extend the operational life of the landfill by one month.”

Growing With the Program
In California, the solid waste division of Bakersfield’s Department of Public Works owns and operates a pair of Morbark 1300 tub grinders for its wood-waste recycling program. The wood recycling program was implemented to lower the volume of material going to landfill and generate a product that could be used by area residents. Morbark’s units meet special needs such as the unexpected uptick in volumes and helping the program grow.

“The program serves the residents of the City of Bakersfield as well as all of unincorporated Kern County immediately surrounding the city,” says solid waste director Kevin Barnes. With a quarter of a million people living in the city, and the 130,000 county residents, the project’s total scope is actually reaching at least 380,000 people.

“The overwhelming majority of our material comes from urban sources,” says Barnes, “mainly tree trimmings or construction wood from remodeling jobs, fence replacements, and so on.”

Bakersfield residents can deposit green waste in 64-gallon containers for pickup, and that material—more than 50,000 tons per year of it—goes straight to the composting area. Material slated for grinding is collected at Mt. Vernon and sent through a Morbark tub grinder to create the mulch product.

“The end product, 3-inch and smaller wood chips, is primarily sold to a huge cogen plant not far from here for biofuel,” says Barnes. “Other markets for the material include landscapers and grading companies, which find it useful for erosion control. The county finds the material equally valuable for erosion control at its landfill, so we supply them with the mulch they need. And finally, we keep some of the material for our own use. Nothing generated as part of our wood-waste program gets left unused.”

“We looked at a broad range of grinders—both tub grinders and the horizontal units available today—and weighed the strengths of each against a list of specifications,” Barnes says. “Price was also a consideration, but performance was the key. Based on those criteria, we selected the tub grinder from Morbark and we feel we made the right decision both in manufacturer and in the type of unit we chose. The kind of material we often get in this area essentially took the horizontal grinder out of the equation.”

Bakersfield’s wood waste program has evolved into a 60,000-ton-per-year success story, thanks to the powerful grinder. Equally important now, says Barnes, is the program’s ability to react to sudden unforeseen increases in volume.

“There’s a seasonality to the program,” says Barnes.

“October through January is the pruning season, and we see our volumes rise by at least 50%. We are geared up for those volumes and have no problem meeting them,” Barnes says.

The department still gets challenged.

A freak snowstorm in 1998 dumped 6 inches of snow on the Bakersfield area, overloading the limbs of trees. “The result of that storm was a one-month period in which we went from an average of 2,000 truckloads of wood waste per week to 7,000 truckloads a week,” says Barnes. “It was chaotic and unbelievably challenging, but we proved that we could rise to the occasion. A smaller, less productive grinder would surely not have afforded us the same performance—and the same results.”

When Bakersfield purchased its second Morbark 1300 tub grinder, Barnes says the purchase was based on a routine life cycle replacement.

He adds that the department now has a luxury it never had in the past.

“Our studies showed these units have a five- to seven-year life cycle, and we were in our seventh year with the older unit,” says Barnes. “We felt it was time to bring in another unit, which would allow us to rotate the two machines when routine maintenance needs arise. However, having two grinders also opens up a number of additional possibilities for the program.

“For example, it is now much easier for us to do some auxiliary portable grinding around the area. After Christmas, we have a number of drop-off sites where residents can discard their Christmas trees. We can now easily take one or both of the grinders to the sites and grind the trees onsite.”

Barnes also says the city has initiated a new program with the Parks & Recreation Department. “In the past,” he says, “when P&R did their regular tree maintenance, the material was hauled to the central processing site. Now, satellite locations set up throughout the area serve as processing sites.”

He says it helps spread some of the workload around, reducing the workload on the central site, which is just about at capacity for a single grinder.

“No single piece of equipment can be held responsible or accountable for a program’s success,” Barnes says. “However, the performance we’ve gotten from the Morbark units has been everything the company promised and then some. More importantly, we’ve gotten excellent support for that equipment.”

He says reducing downtime is as important to Bakersfield as it is to someone in the private sector, and product support weighed heavily on the decision when choosing the second unit. “We’re doing things now that, at the program’s outset, we never imagined we’d be doing. And we’re seeing new possibilities all the time.”

Look for onsite training at start-up on every machine. Also look for updated manuals, product bulletins, and factory training programs. Some dealers conduct demonstrations with prior arrangement. Whatever way you research, it’s important to check out operations similar to yours.

Ward says the buyer should do some homework before getting a grinder or shredder. “Quite simply, the customer needs to ensure that what they buy is designed to and capable of processing the intended material day-in and day-out without requiring significant daily or weekly maintenance.”

“Oftentimes, grinders or shredders are impressive during a demonstration but don’t hold up over time. The cost of maintenance and downtime adds up quickly with the wrong equipment.”

Ward suggests visiting onsite. “Go see an installation that is at least a year old—doing similar materials—to see what the equipment really looks like,” she said. “Low capital cost isn’t an argument that holds up well to justify purchasing the wrong equipment that will cost significantly more in the long run.”

“Onsite training until the customer is fit.” That’s Semler’s motto. “We’re also present on the first shaft change once it’s due, just to make sure everything is done right. And we offer, if they want, to train their own technician in the German factory.”

Semler advises not to just look at the price tag. He says to look at efficiency and cost. “If the machine is not efficient, it will cost you more.

“If the base purchasing price is already low, you should see a great deal. Do your homework, check out the market, talk to existing customers about their experience,” Semler says. “Look at and physically visit sites where machines of your interest are running, compare prices and technologies and eventually make an informed decision.”

Work With Me, Babe
“We think outside the box and work very closely with our customers to provide the most cost-effective, long-term solutions, with as much flexibility in the system to accommodate future market changes that our customers will face,” Benway says. “We do that by listening to the customer first and foremost. Then we recommend the best solution to their needs. This process takes time and flexibility for adjustments to the system design in order to provide the most effective long-term solution. It is better to work out as many concepts on paper as needed and, as a team, agree on the final solution prior to manufacturing and installing equipment.”

PHOTO: SSI

“We work extensively with our customers,” says Morey. “In the recycling of shingle waste, we have worked diligently with the shingle recyclers to develop machines that wear better and produce a more uniform product without creating heat that may gum up the machine. Working with the customers has tremendously improved the processing of shingle waste into an acceptable raw material for hot-mix asphalt while eliminating the need to screen the processed shingles. Our customers generally meet and work with our engineers to get the changes that they want in the machines.”

For another Bandit customer, the company modified the 3680 to follow a rotomill to properly size and mix ground asphalt. Afterward, it could be fed into a paver in a cold-place paving operation.

“We frequently run service schools for our customers and dealers,” says Morey. “We also provide a trained service technician when we deliver each machine. The technician spends a couple of days with the customer and machine, making sure the operator and owner are familiar with all the functions of the machine and the maintenance required.”

Bandit products are supported by an extensive dealer network, says Morey. “There is a group of trained parts and service technicians available via phone or online. We have factory service and repair and six complete service trucks that are equipped with nearly all of the parts and tools necessary to operate our Beast Recyclers,” he says. “We have a staff of trained service technicians that travel the country servicing and demonstrating our machines.”

“People are just stupid sometimes when it comes to their own safety,” says Semler. “Something downright dangerous would be to stay and remain within 20 to 30 feet of the machine while processing material. Or to try to do anything close to any spinning wheel, roller, etc., to ‘save time’ and not shutting down the machine in the first place.

“The penny spent in preventive maintenance is the dollar saved in repairs. That’s what I believe in and what’s true for a lot of things, including heavy equipment and HAMMEL slow-speed, high-torque primary shredders. Just a few simple daily things, like basic daily cleaning, unwrapping everything that wrapped around anything spinning, regular fluid control in the morning, regular check for little leaks, greasing and oiling—all these simple things can prevent breakdowns.”

Safety features are part of the design in many cases. Morey says because Bandits grind in a downward direction, material is pulled into the machine. “Safety lock-out systems are provided so the machine can’t be operated when the machine is being serviced. Safety locks secure the top feed wheel so that it can’t accidentally fall on someone who might be servicing the unit,” he says. “Kill switches are mounted on the side of the machine. All the units are operated with a remote control, so there is no need for an operator at or near the unit. All of our units have had these basic safety features from the onset.”

Final Product Affects All
As a large production builder, Max Wade, vice president of Artistic Homes Inc., Albuquerque, NM, has seen the economic impact of C&D waste. “Two of the biggest issues we run into are the amount of money we spend on construction waste and the environmental impact we have as such a big-volume builder,” he says. “Since we’ve been using Packer Industries horizontal grinders, our waste stream has been cut drastically, our handling costs are way down, and we’ve been able to reuse these organic materials as valuable resources.”

Wade builds some 800 homes a year at the affordable end of the market. His company is the largest local home builder in New Mexico. He says he is saving almost $285,000 a year on dumpsters by recycling his construction waste. According to Wade, $900 to $1,100 was being added to the cost of construction of his typical 1,300-square-foot home because he was sending the contents of 22 dumpsters a week to the landfill. He has since cut those expenses by 95%.

Wade bought two Packer 750 grinders. The grinders were priced at $85,000, and he says they can handle a large volume of material, are safe for workers, and also fairly easy to maintain. The grinders extract about 95% of the nails that go into them. The nails are then culled by a magnetic pulley and spit into a bucket.

The grindings are mixed with cow manure and then stockpiled. After two years, they become compost for topsoil, potting soil, soil for football and baseball fields, and more. The product sells for about $16 a yard. Wade says he gives grindings away in exchange for having them hauled off.

Consultant Dagmar B. Epsten, president of The Epsten Group Inc., in Atlanta, GA, says C&D waste and its disposal are important aspects of every project. “As a LEED consultant, we strive to divert a minimum of 75% of construction and demolition waste from landfills for most of our projects. At Georgia Tech’s Technology Square, we achieved that goal and two LEED points for the LEED Silver certified management building, thanks to Packer Industries.”

“Using grinders and shredders has its drawbacks—such as landfill draining and gas generation issues,” says Giebelhaus. “And annually, costs to shred are roughly $711,000, but the fiscal gains of accessing to airspace far outweigh the costs and problems.”

Challenges in the Future
According to Ward, some of the biggest opportunities and challenges in C&D waste are imposed by developing regulations. “While states (i.e. Massachusetts) are beginning to seriously look at banning landfilling of C&D materials, which supports C&D recycling, other regulations are challenging the ability to develop cost-effective end products,” she says. “For example, there is a lot of discussion about whether utilizing processed C&D for alternative cover increases levels of hydrogen sulfide gasses at the landfill. In some cases, fuel or mulch products derived from mixed C&D are considered problematic due to high mercury concentrations or other contaminants.”

This means the C&D recycler has to be able to identify problematic materials and remove them from the process stream, or hand-select only the clean material to go in end products. Given the complex nature of mixed C&D, this is a significant challenge.

Morey says the biggest challenge facing the C&D waste industry is finding a market for the material that is being processed. “New markets are developing for C&D waste, including energy,” he says. “The recycling of shingles and tear-off shingles is becoming extremely more prevalent. Shingle waste is being recycled into hot-mix asphalt.”

Morey also predicts that future developments with the C&D reduction and recycling machines will focus on machines that produce a marketable end-product, produce more, and operate at lower costs.

“The permitting process to open a C&D processing facility is one of the most challenging things in the future,” says Benway. “It is a lengthy, expensive undertaking, which in the end is restricted.”

Benway sums it up: “A business needs to be profitable in addition to providing a benefit to society by recycling this waste stream and reducing the residuals that end up in a landfill.”

The willingness to spend hundreds of thousands of dollars, a little planning, homework, and an onsite visit or two can help you ensure you choose the correct grinder or shredder.

Marsha DeClue, based in St. Louis, MO, is a correspondent with several business journals.

MSW - January/February 2006