A recycler never knows what he or she will find in a construction and demolition (C&D) debris container. Every load may contain a surprise, making it more difficult to recycle. That’s why creating guidelines and supervising incoming material is essential for businesses. Most try to keep nonacceptable items out, but it has become a common problem for many facilities. With ever-changing types of material ending up in C&D loads, it’s vital to select the proper recycling equipment.
Waste composition, collection and transportation methods may vary across the country. Transfer stations tend to compound the problem, and clients are usually more concerned with construction schedules than with taking time to recover packaging materials from the job site. Everyone has deadlines and budgets to keep, but the effectiveness of recycling programs and seasonal changes may limit the ability to capture certain materials.
No matter how careful a recycler is, the value of certain materials is diminished when exposed to others. To improve the material stream, a recycler has to ask the following questions: Can the material in question be sorted and kept clean? Is it a struggle to process different material streams with the same system? Am I looking to add or eliminate presort stations? Does the primary screen capture all the fines material, or do fines ride on top of larger items and surf across the screen?
Regardless of the material being processed, screening solutions have become an important component of every recycling system.
SCREEN PERFORMANCE AND RECOVERY RATE
Screen performance has a tremendous impact on the recovery rate of C&D debris. Conventional screening methods, such as trommels or star screens, have limitations, while new dynamic disc screens are designed to prevent clogging and wrapping issues that occur with conventional screens. Dynamic disc screens make it easy to adjust the screen size for different types of materials. In terms of versatility, capacity and footprint, a dynamic disc screen is a much more efficient solution.
Vibratory and rotating drums that have the same capacity will require two to three times the footprint. The Eco-Star screen by Aggregate Equipment Inc., Leola, Pennsylvania, for example, has rotating shafts that constantly flip the material and capture the smaller items. Film and plastics tend to float above the flat discs. The remaining items discharge off the end of the screen in a metered flow to enhance further separation. The screen is designed so product sizing and efficiency remain constant.
It’s been noted that successful recycling operations handle debris fewer times than other systems and use effective screening methods to separate the stream by size. The quality of the screening process determines the efficiency and performance of subsequent processes, such as ferrous metals recovery, density separation, manual sorting/inspection and volume reduction. If the fines aren’t removed by the primary screen, chances are the sorted products are contaminated. Any remaining fines and debris on the final sort belt typically end up in a landfill as waste. In that case, the fines content doesn’t matter.
But things are changing, and many C&D recyclers are finding ways to divert the residuals from the landfill by creating an alternate fuel product. In these instances, getting all the fines out becomes a higher priority.
The sorters and automated processes focus on capturing recyclables and removing contaminants to improve the quality of the fuel product. With the negative sort process, all materials that remain on the sort belt are transformed with size reduction technology and screens to produce alternative fuel. If the fines remain on the belt, the contamination level may exceed alternative fuel quality requirements, which is why the efficiency and performance of the screening process is crucial. Proper sizing and recognition of material is vital to improve the effectiveness of automated and manual sorting.
When markets tighten up, suppliers of quality products will outperform the competition. Contamination and purity levels are directly related to screens and secondary sorting methods. To produce high-quality, low-impurity commodities, equipment must be properly selected; however, properly recovering materials from the waste stream is an expensive proposition. The markets fluctuate and the intrinsic value of recovered items are less than the dollars spent capturing them.
It’s risky to stockpile large quantities of sorted materials and hope the markets will improve. That’s why it’s important to capture the items that are profitable.
Constantly evaluating performance and maintaining equipment can reduce downtime and improve the bottom line, but the key is investing in the right equipment in the first place.
Doug Logan is the applications specialist for Aggregates Equipment Inc., Leola, Pennsylvania.
Preserving the integrity
Features - Demolition Training
Deconstructing a building and reusing its materials are becoming popular environmentally friendly trends in the demolition industry.
How much of your barn, garage or basement is full of material you pulled out of projects that you just could not bear to toss into the landfill? It’s likely way too much. Whether we are builders, demolition contractors, deconstructors or developers, we are in this business because we love buildings and machines and the materials in them. I was a remodeler/cabinetmaker for 20 years, and I know the pleasure of ripping old material out and the pain of throwing away good material. Yet, our barns and garages can only hold so much.
Soon after I left my previous career, I discovered the building material reuse industry, and throughout the last 15 years, I have watched this industry expand. Whether it’s reuse retail organizations and businesses, lumber and architectural millwork businesses or deconstruction outfits, the industry is growing.
When writing this article, I thought about what I didn’t know years ago and what folks in the construction and demolition (C&D) recycling industry might want to hear about.
Why reuse? Because raw materials should no longer be turned into finished products then moved down the chain until they turn into waste. The recycling industry has done an amazing job over the last 30 years. “Give a hoot, don’t pollute” and other early messages changed our nation’s way of thinking about materials. However, over time, our consumer culture began re-emphasizing the allure of buying everything shiny and new. If an item wasn’t straight from the factory, it was somehow dirty and dangerous. That was the seed that was planted in our culture that led to the incredible waste in our society.
Being in the building and reuse industries allows an individual to know what can, and should, be saved, which always ends up being a lot more than most people recognize. Historic materials are not the only items that are reusable, either. Windows, doors, flooring, dimensional lumber, plumbing, built-ins, lighting and hardware can be reused. Sometimes items are reused for needs-based reasons, sometimes they’re reused for craft- or mission-based projects, and sometimes materials are reused just because the material is so gorgeous that one can’t fathom letting it go to waste.
The real trick, however, is understanding the condition of the material. People will buy used building materials if they are in reasonable shape. If the condition is good enough, if it is not degraded too far by either extraction or transportation, then the inherent value of the material or product will be preserved. You would be amazed how quickly the value drops in reused building materials when they are not handled properly. This is a critical factor—once the value is lost, then all the incentive to save a piece is gone.
For building material reuse to be a viable industry, a healthy profit margin is required. Take away the inherent value in the salvaged material, and it’s incredibly hard to gain that margin back. Labor to extract the materials or products, the cost to handle and ship them and the cost to market and warehouse or retail them all demand that materials be removed and handled in such a way that the value remains as intact as possible.
This is where professional deconstruction services become important.
PIECE BY PIECE
Deconstruction is the process of taking something apart in a way that preserves its integrity. In essence, the same care that went into constructing the building must go into taking the building apart so materials can be salvaged. Whether it’s a set of kitchen cabinets, a house, a barn or a 100,000-square-foot factory, care must be taken to remove and transport its components in a secure manner. This is an essential part of preserving the value of these materials, as well as the sequestered value of the raw materials and the embodied carbon within those materials.
For example, almost every remodeled kitchen already has had a kitchen in it previously. A contractor can get behind a cabinet with a crowbar and pull it until it pops off the wall or take a bit more time to figure out how and where it’s attached and gently slip it off. There lies the art and science of deconstruction.
Whether it’s a set of cabinets or a house, it comes down to the same thing: Taking the time to disassemble, remove and transport these materials right is how we retain their value and potential profit. Patience and meticulous execution, rather than speed, can pay dividends down the road.
Building material reuse organizations and businesses are located across the country, and they are getting easier to find thanks to the increasing emphasis on reducing waste, especially C&D debris. When it comes to skilled, experienced deconstruction contractors, they’re a bit tougher to find. Deconstruction is a small, but growing, subindustry of building material reuse. However, they can be found if you know where to look. Many reuse retailers have a deconstruction program, and many demolition contractors are beginning to consider the merits of deconstruction. If nothing else, look within the industry and tap into connections to see who is doing this well and take their lead.
The important thing is to take the time to learn how to extract the materials, and thus the value, from whatever it is that is being moved on to its next life. It is not only good for the environment, it can be good for your bottom line.
Joe Connell is the executive director of the Building Materials Reuse Association, Cranberry Isle, Maryland, and he can be contacted at email@example.com.
Intro to implosion
Features - Cover Story
Two high-rise dormitories on the University of Nebraska-Lincoln’s campus were recently imploded to make way for new student housing.
Back in September 1963, just months before the assassination of President Kennedy and the rise of Beatlemania would consume the nation, college students at the University of Nebraska-Lincoln were settling into the newly opened Cather and Pound Halls for the first time.
More than 54 years later, the university’s oldest high-rise residence hall complex was imploded on Dec. 22, 2017, in favor of the campus’ newer suite-style housing that has been built in recent years.
While the university had been planning the demolition of the 13-story structures for several years, Tulsa, Oklahoma-based Ark Wrecking wasn’t named as the project’s demolition contractor until May 2017. Ark Wrecking, which has been in the demolition business since 1950, subcontracted the implosion preparations and execution to Phoenix, Maryland-based Controlled Demolition Inc. (CDI).
The decision to implode the building was made by the university, which wanted to limit the risk associated with the demolition.
“The university hired a demo consultant to come and look at their buildings to come up with a plan for the best possible scenario to get those two buildings down safely with little to no risk to the general public,” Harrison Williams, project manager at Ark Wrecking, says. “They talked about breaking it down mechanically, both balling it down or utilizing UHD (ultra-high demolition) tools, but the problem with both of those options is the time of exposure during the demolition would require multiple weeks. They were more interested in the building being on the ground immediately.”
Prepping the buildings
After Ark Wrecking rid the building of combustibles, the next order of business was to select an abatement contractor to begin the asbestos removal. The job was awarded to Bockmann Inc. of Lincoln, Nebraska, which got to work right away.
“Getting the asbestos abatement under contract and started in early May was really the key to getting the project going and maintaining the schedule the university was interested in,” Williams says.
Once the asbestos abatement was completed, it was time for Ark Wrecking to prepare the buildings for implosion. The company performed a soft strip of carpets, wood and other deleterious materials so that the postimplosion debris could be recycled. It then gutted seven floors in each tower by removing all the nonloadbearing block walls and masonry, as well as the interior partitions, to strip the buildings down to the mainframe.
To complete the interior demolition work, Ark Wrecking purchased a Brokk 110 remote-controlled demolition robot with a hammer attachment. The Brokk 110 was chosen, according to Williams, for its ease of climbing stairs and fitting in tight spaces, which was needed to maneuver through the facilities’ door frames.
The shear walls around elevator shafts and stairwells were modified per CDI’s design to create flat wall elements, which CDI’s drillers could effectively prepare for the placement of charges.
Ark Wrecking also placed at-source protection made of chain link fence and geotextile fabric around columns and walls to be shot by CDI. Additionally, it placed chain link fence and geotextile fabric curtains around the shot floors to help contain any particles that escaped the at-source protection.
During this time, the common area adjoining the two high-rise structures was conventionally predemolished.
CDI went to work reviewing the project details at length when preparing the company’s subcontract proposal for implosion preparations and execution.
“We reviewed the structural plans provided, inspected the structures in the field to confirm information provided by those structural drawings and reviewed the nature, location and condition of adjacent improvements to remain undamaged,” Mark Loizeaux, president of CDI, says.
The decision to implode these buildings made a lot of sense, Loizeaux says, and helped minimize risk for all parties.
“From CDI’s perspective, implosion was selected because of the size and suspension methods of the precast panels around the perimeter of the building, the proximity of adjacent improvements and public/student rights-of-way to remain,” Loizeaux says. “Dealing with those large precast panels would have been difficult, at best, over several months of dismantling if conventional demolition had been used. The duration of exposure to the public and student body for that extended period of time, while the precast panels were picked off, would have created long-term risk that the university, and the main contractors, would have wanted to avoid.’
Loizeaux says the precast panels came down in seconds during implosion. “The dramatic reduction in duration and nature of risk associated with conventional dismantling would have been enough to steer the university toward an implosion approach designed and executed by an experienced and qualified contractor.”
Cleanup and recycling
The materials to be recycled were somewhat limited because the building was composed mostly of block walls and concrete deck ceilings, and the floor tiles that were removed during abatement were unrecyclable.
“During our gut-out process, we recycled approximately 30,000 pounds of precious metal, basically copper and aluminum,” Williams says. “We also extracted roughly 22,000 tons of concrete.”
He adds, “The university had worked out a deal with the city, which owns the Bluff Road landfill in Lincoln, for the landfill to sort through all that concrete and recycle it to use for roadbed for road construction within the landfill site, which is around a 120-acre site. There was very little ferrous material.”
Ark Wrecking used 80,000-pound track excavators to help with the material cleanup and is continuing to work on-site with crews of five to eight employees to complete the project by its April deadline.
Ark Wrecking tabbed Gana Trucking & Excavating in Martell, Nebraska, as the earthwork contractor to help with the material cleanup.
A smashing success
Every demolition job has certain risk factors associated with it. The implosion of Cather and Pound Halls was no different.
In addition to the regular prep work, Ark Wrecking and CDI had to consider the buildings’ proximity to nearby structures when planning their project.
According to Williams, the dorms were flanked on two sides by other buildings, and there was a new building in front of the property with a three-story curtain wall that also warranted some consideration.
“The unique challenge of this job was just the close proximity to other buildings,” he says. “So, the biggest challenge was the amount of protection and precaution we had to take to protect the surrounding buildings. My biggest takeaway is you can never figure enough protection.”
In the end, the demolition and implosion went off without a hitch, which will allow the site to be converted into green space by the university in May or June.
According to Loizeaux, proper planning and collaboration helped to negate any potential issues that could otherwise have occurred during the demolition and allowed the project to go on as scheduled.
“From CDI’s perspective, the implosion of Cather and Pound Halls was a textbook operation with the structures behaving precisely as planned,” Loizeaux says. “The university representatives were professional and easy to deal with, and Ark Wrecking brought all of the experience and tools to the table to prepare the structures exactly to CDI’s specifications. The successful implosion of these two structures was the result of a team effort by all.”
The author is editor of Construction & Demolition Recycling and can be reached at firstname.lastname@example.org.
Features - Commodity Focus // Copper
While copper scrap has been flowing steadily into yards, demand could be more robust.
Continuing a trend that began in the fourth quarter of 2017, copper scrap dealers are seeing extended delivery dates from their domestic consumers as supply outpaces demand. This situation, as well as softer export buying, is contributing to the wider spreads recyclers are reporting.
Moving, though slowly
The nonferrous marketing manager for a scrap processing company based in the Midwest says that while U.S. copper scrap generation varies by grade, it has been increasing generally. “Higher terminal market pricing in conjunction with China backing away from the copper market has certainly increased domestic supply on the copper commodities.”
He characterizes generation from the demolition and construction sectors as being stronger than he has seen in the past few years. “Capital investments being made by domestic manufacturing companies to replace and upgrade older equipment are generating increased scrap. The material pickup is seen across the board, from increasing scrapped out CNC (computer numerical control) machines to entire plant demolitions,” the nonferrous marketing manager says.
The chief operating officer for a scrap processing company based in the Northeast says copper scrap generation is about where he would expect to see it in the South Atlantic region, which is where he is based. “It is probably a little bit above where we would be traditionally.”
He attributes that increase in obsolete supply to the upward trend in COMEX pricing for copper, which he says is spurring more interest in the metal.
ISRI, citing data from American Metal Market (AMM), an online provider of metal pricing, states “the discount on No. 2 copper scrap delivered to U.S. refineries stood at around 42-43 cents per pound in early December 2017. In comparison, the spread on No. 2 copper scrap was around 17-19 cents in June 2016.”
The association also mentions that “scrap market participants are questioning whether terminal market copper prices reflect physical market fundamentals or speculation,” which has been fueled in part by China’s clampdown on scrap imports and expectations that the country will increase its consumption of copper cathode.
A broker based in the Midwest also points to steady generation of obsolete material. However, he adds that “you can’t match it up” on the demand side. “No. 1 heavy copper solids and tubing is hard to find, but I have demand for it, while bare bright is everywhere, but I can’t get mills to take it.”
The marketing manager attributes softer demand for No. 2 copper to lower-than-expected volumes of orders at rod mills and ingot makers. “Otherwise, higher copper markets have caused an increased amount of supply to enter the market, thus driving pricing down. But we believe the wider spreads to be a result of increased supply amid steady demand.”
He continues, “We believe that commodities like bare bright will see demand pickup as the Chinese consumers are forced to compete or pay up for cathode or equivalently clean copper units.”
As of mid-January, the broker characterizes demand from domestic consumers as being lower, adding that consuming facilities are not running at 100 percent. “They are generating enough return scrap to get what they need,” he says.
The nonferrous marketing manager says it’s common to see a seasonal depression in copper scrap demand going into the end of the calendar year. “Although we did not see much of a pickup in January, indications are that demand will pick up in February and remain strong through the spring and summer,” the marketing manager says.
“Consuming facilities are reporting lower than anticipated sales for finished goods at the moment, but order books appear to be quickly improving,” the nonferrous marketing manager adds.
The chief operating officer says delivery appointments have not been readily available, though—at three weeks to 30 days—they are not as far out as they were in the fall.
The export picture
The nonferrous marketing manager says export buying activity has been mixed. “Understandably, our Chinese customers have been unable to purchase the same materials they had been over the past several years, but other consumers have emerged,” he says.
“In recognition of the transition that is occurring from Chinese consumers moving to other countries, the Indians have been aggressively attempting to gain market share,” the marketing manager adds.
According to AMM, the Chinese government has issued the first two rounds of solid waste import licenses for 2018, and copper scrap import license numbers and tonnages are down by more than 94 percent each.
The marketing manager says these reductions are a “temporary inconvenience.” He adds, “China has taught the rest of the developing world a valuable lesson as it pertains to acquiring affordable raw materials through the leveraging of their labor markets. We are already seeing several customers moving operations to other countries where there is high demand for materials and low costs of labor. We are still moving many of the commodities that we had been, we’re just delivering to different ports.”
When asked if his company has made any adjustments to its operations in response to the changes occurring in China, the marketing manager says, “Any changes that we have made are simply to process materials further as opposed to selling as-is.”
He adds that this decision was driven by economic considerations. “If a market for material in one form disappears, we will process the material further until we have a saleable commodity yielding the highest margin available.”
The chief operating officer says his company has been shipping very little material to China.
In addition to the widening spreads recyclers are dealing with, rising transportation costs associated with the shortage of trucks and drivers are eating into the margins of copper scrap dealers.
“The shortage is certainly being seen on the pricing being offered by transportation companies,” the marketing manager says. “As of now, we are paying considerably more to move material but have not ultimately had many issues securing transportation if you are willing to pay the going rate.”
The source based in the Southeast says the higher prices and tightness in the trucking sector have only gotten worse since the initial disruptions caused by the hurricanes in Texas and Florida took effect. This has been caused by the regulations requiring drivers to electronically log their hours, which went into effect in mid-December 2017.
“It’s not a bad thing,” he says of the new requirements, “but it will take a while for the market to adjust.”
Despite the challenges currently facing copper scrap dealers, the marketing manager based in the Midwest remains “cautiously optimistic.” He says, “We believe that we will see a higher average price for the red metals as compared to 2017; however, domestic mill demand remains in question. If order books continue to build, and the Chinese economy remains strong, then we believe that we will see spreads come in considerably.”
The author is managing editor of the Recycling Today Media Group and can be emailed at email@example.com. This article appeared in the February issue of Recycling Today, a sister publication of Construction and Demolition Recycling.
Finding the right fit
Features - Equipment Focus // Processing Attachments
There is much more than invoice cost to consider when upgrading or purchasing a new mobile shear attachment.
When it comes to acquiring a mobile shear for a specific application, one of the most common errors purchasers make is looking strictly at the invoice cost and not at the overall operational or ownership cost of a unit over time. In today’s tight economic climate, employees are doing their companies a disservice by spending money when it can be better conserved. Being more thorough in the cost analysis phase of shopping around can help companies stay profitable and ahead of the competition.
The starting point for success when acquiring a mobile shear is being able to analyze business operations and understand exactly what the costs are when it comes to profitability versus operational costs. Most owners/purchasers of mobile equipment get stuck in the rut of “buy low, sell high,” but that philosophy needs to be grounded in facts, not feelings. Understanding the fixed costs and, most importantly, variable costs for processing material is where a company can excel. Fixed cost (FC) is the purchase price of equipment. The variable costs (VC) are the owning and operating expenses of that equipment. Being aware of these differences can help keep profits high.
WHAT TO CONSIDER
The application of the mobile shear should be considered first when making a decision to buy equipment. The mobile hydraulic shear is designed for cutting and processing various ferrous metals, excluding cast. This equipment can also process nonferrous metals, but in most cases, processability will vary. A potential buyer should ask him or herself the following questions when considering the application: “How often will I be using the shear?”; “What will its processing uptime be?”; “What type of material do I plan on processing?”; “Why am I processing it?”; and “What is going to be done with the material after it is processed?”
For example, mobile shears can be used for sizing large materials coming into the recycling yard or for the first stage in sizing upstream for a demolition project. The buyer will have to discern whether the unit will be the cornerstone of the project’s processing requirements or will split time in the facility. He or she should also consider whether it will work out of the yard, perhaps on a project site, or be rented when it is not being used? Once the processing requirements are defined and decided upon, the size of the unit needed and the carrier it will be mounted on can be decided.
SMALL, MEDIUM OR LARGE?
The size of the mobile shear needed is dependent on the material type and size being processed, with the former category taking precedent. For all applications, look at processing 80 to 90 percent of the material that has been targeted. The other 10 to 20 percent can be left to be processed by other means. Acquiring a mobile shear to process 100 percent of the material, unless it is controlled, is not practical or cost effective. One of the best ways a company can find the right size attachment for its needs is by asking an attachment supplier to show the processing and appetite capacity of the attachment, and then weighing the available options.
CARRY THAT WEIGHT
Once the buyer settles on the right mobile attachment size, he or she needs to find a suitable hydraulic excavator. This is a critical step for putting together a successful and profitable processing package. A mobile shear manufacturer representative can help in this regard and show the options available. Any previously owned hydraulic excavator should match the attachment’s hydraulic- and weight-balancing requirements to operate at maximum efficiency.
The hydraulic excavator specifications need to be studied as well. Items to be reviewed include carrier operating weight, hydraulic lift capacity, hydraulic pump flow capacity and operating pressure. Other factors to consider include whether the machine needs to be on tracks or has wheels and whether the unit can handle the attachment mounted on the boom of the carrier or needs it to be mounted on the stick. Properly matching these considerations with the operating requirements of the attachment will allow the attachment to perform to its best ability.
Equipment wear part and maintenance costs need to be tracked over time to give an accurate return on investment (ROI). Many companies do not track these expenses and cannot report an accurate rate of return on their projects, or, in the case of scrap processors, what their actual net profit is on a ton of processed material. Using the equipment manufacturer’s efficiency ratings or tracing some basic consumption costs can help produce an accurate formula to discover the actual total wear part and maintenance cost (TWPMC). The following formulas can be helpful when trying to ascertain what the profit margins are per ton of material processed. Using these metrics, you can figure a healthy ROI that is attainable.
TWPM = [years x parts] + [labor rate x service hours]
Ownership cost per hour = total equipment net investment / total operational time
Total ownership and operational cost per hour (O&OC) = total equipment net investment + total operational costs of equipment (TOCE)
Operating cost per ton of material processed (OCTP) = tons of material processed / O&OC+TOCE
Net profit per ton, in dollars = material selling price per ton (MSPT) - [OCTP + material purchase price per ton (MPPT)]
A quick analysis of the operational variable costs over time will result in a much more accurate picture of the profitability of an operation or project. With this information in hand, a company can be confident in bidding new business and expanding its operation with healthy results.
Salvatore LaCorte is the scrap and demolition products sales director for Rotar North America, Willoughby, Ohio.
All formulas and accounting examples are merely simplified samples, your specific needs and outcomes may vary based on your input information. Check with your accountant and tax advisor before certifying the results.