Baler Supplement -- The Logistics of Baling

The art of baling can be more complicated than one may think. Sure, the process of baling itself – squeezing loose material into a dense, rectangular cube – is not rocket science, but when you consider all the other processing functions and considerations that accompany a successful baling operation, then the picture becomes more complicated.

Therefore, industry experts say that recyclers must give serious thought to how they set up their baling operation so that there is maximum output and efficiency and minimal maintenance.

SPACED OUT

Whether an operation is moving up from a downstroke baler, or starting from scratch, there are several areas that have to be considered. Among those areas are space requirements, manpower requirements, increased energy costs, throughput capacity and the types of materials to be baled.

“The first thing that I tell someone who is looking to install a high-production baler is to make sure you have more than enough space to handle the material,” says Buddy Himes, owner of Himes Service Co., Waco, Texas. Himes is a veteran of the recycling equipment industry and currently sells and sets up processing arrangements for recyclers. “In fact, I almost always tell a processor to oversize – to allow for more space than currently is needed. I know that is sometimes hard to do because that means more cost is involved, but by building bigger you can avoid headaches down the road.”

Those headaches include material handling and storage problems, as well as not having enough space to properly perform equipment maintenance.

Others in the industry agree with Himes. “The first and most obvious design factor is the amount of bale storage and tipping area required,” says Erik Eenkema van Dijk, executive vice president, Van Dyk Baler Corp., Stamford, Conn. “ I’ve never heard a plant manager yet who says that they have too much space for either of these.”

Secondly, consider flow through the plant, advises Eenkema van Dijk. “Reduce or eliminate cross-traffic with loaders and trailers, if at all possible. Keep tipping and loading areas away from each other to reduce congestion and confusion.”

He also says to always design over-capacity into sorting systems and baler specifications to be able to effectively handle material surges that normally occur.

Lastly, Eenkema van Dijk warns to never tie two systems together. “Keep sorting systems and balers independent from one another – otherwise, if one goes down, the other will be useless.”

Great Lakes International Recycling, Roseville, Mich., took a slightly different approach when it upgraded its facility by replacing three outdated balers with a new high-capacity single-ram extrusion one. “We did not oversize our entire operation for increased material flow,” says Mike Redmond, project manager at the company. “Our sorting operations, which are the most labor-intensive, were designed with more capacity. Therefore, when we see increases in the materials received, we are able to sort them within a day’s work, but bale them with some overtime using a skeleton crew.”

Great Lakes International Recycling annually process approximately 30,000 tons each of high grade paper, newsprint and old corrugated cardboard (OCC), as well as 7,000 tons of nonferrous metals, 2,500 tons of ferrous metals, 3,000 tons of curbside glass, 1,000 tons of post-consumer resins, and a small but growing amount of post-industrial plastics. The company has one high-capacity single-ram extrusion baler for processing paper grades and a pair of two-ram balers for processing nonferrous and plastics.

“Our sorting and baling layout centers on the feed conveyor to the baler,” says Redmond. “The news, high-grade, and OCC sorting operations all deliver materials adjacent to the baler feed conveyor. The news sorting occurs on one side of this conveyor, the OCC on the other side, and high grade sorting is accomplished at the end opposite the baler.”

While the company has two older two-ram balers for processing nonferrous and plastics, Great Lakes International Recycling’s paper runs through $2 million worth of baling and sorting equipment that became operational in March 1997. Included in the purchase was a single-ram extrusion baler, a newspaper sort line (which includes a 70- cubic-yard live-bottom storage container), and an OCC sort line that includes two disk-screens. The first screen separates paper and OCC, and the second separates fines from the paper recovered from the first screen, then loads the paper into a 60-cubic-yard live- bottom storage container.

“We upgraded to the current system for a number of reasons,” says Redmond. “The three balers that we replaced were old, and in constant need of repair. We also desired to move our OCC sorting operations inside, out of consideration to our employees and our neighbors. Furthermore, since our energy costs were high, we wanted a baling system that did not require conditioning (shredding) of our news and high grades. We have been able to improve our efficiency with a smoother flow of materials meaning less transportation and storage of work in process.”

MATCHING THE BALER

Hand-in-hand with space requirements is choosing the right baler in the first place. It is recommended that a recycler do the necessary homework in this area as there are a lot of options on the market and strong opinions about baler types and designs.

Himes, who works with all baler types, had these comments about the subject. “Single-ram extrusion balers work best with paper,” he says. “I recommend models that have pre-press flaps instead of shears because of the wear and tear on the shear blade and baler without the flap. Single-ram extrusion balers can also process cardboard and plastic bottles. But except for some newer design innovations, the hopper on a single-ram is smaller than a two-ram, making loading OCC easier with a two-ram. Also, if processing plastic bottles, I would recommend adding a perforator when using a single-ram extrusion to reduce the memory of the bottles, making it easier to bale them. But, generally, two-rams are better for baling plastic bottles, cans and extrusions.”

A two-ram baler can process more types of materials; however there are many other considerations to look at before deciding on which one is the right one for your operation.

Once the baler type is chosen, the layout has to be carefully examined. For instance, a single-ram extrusion is basically an in-line operation, whereas a two-ram ejects the bale out to either side. Therefore, a two-ram can be placed along a wall, but not a single-ram extrusion baler.

THE ULTIMATE PROCESS

The next step is to determine what level of processing is to be achieved prior to and after baling. Since this can vary greatly from system to system, Recycling Today decided to look at what the ultimate system may look like when baling paper – probably the most common commodity baled by recyclers.

Our ultimate system actually begins outside of the recycling plant with education. Most progressive recyclers educate their accounts to separate at the source, and actively revisit their clients to keep the material flowing properly.

In addition, automated sorting system designs for high-rise buildings and apartments allow residents to easily separate materials on the spot.

Inside the recycling plant there would be some type of dumping system, such as a truck dumper, to efficiently drop off the incoming material.

Next, conveyors would move the material to a sorting line that would include metal separation via a magnet and eddy current, a disk/star screen to remove OCC, a trommel to separate small fines, an air knife to bounce out plastics, and possibly some kind of optic sorter for removing and separating glass. There would also be some level of manual picking as a final check.

In this positive sort system, the paper would be conveyed up to an infeed system to the baler as the rest of the material would be conveyed to other sites within the building or outside.

The use of photo-eyes and metering conveyors to feed the baler can help to assure proper loading.

 Finally, a fluffer ensures that the material is distributed evenly in the baling chamber for better density. If baling light or shredded material, a screw-like device can help to push the material into the bale chamber at a faster rate than with gravity alone.

On the output side of the baler, increased automation would include roller conveyors that move bales to storage areas and even palletize the bales for optimum loading. Modern forklifts would be used to haul bales when needed.

“A system like the one described above would be the most automated one that one could produce on the market today,” says Himes. “You could even add walking floors to go one step further to move material from bunkers or the tipping area to the sorting line.”

A TAKE ON MISTAKES

Larger recycling operations normally have in-house personnel to adequately lay out and design their own new recycling centers. However, most mid-sized and smaller operations that are making that jump to automated processing lines should consult companies and individuals in the industry that do this type of work full time.

In general, it seems that most of the mistakes with a baling operation layout design involve improper flow of material and traffic control problems, according to industry representatives.

“Don’t think you know it all,” advises Himes, who has seen even some of the large processors make serious miscalculations when planning a baling operation.

“I would have to say the biggest mistakes I have seen involved very large processors who had in-house engineers that made critical design errors,” he says.

One company had built a storage bunker for its baler, but made the bunker too small. “The bunker wasn’t even large enough to hold material to make one bale,” says Himes. “A bale of paper usually weighs about 1,400 pounds, so you have to have a bunker big enough for at least that much, and preferably large enough to make several bales at a time.”

Another company made a mistake with bunkers, also, but instead of making them too small, the bunkers were too close to the baler and did not allow for a method to get the material from the bunker to the baler. “The three-sided bunker did not give enough room for a loader to get in there and move the material to the baler’s infeed conveyor because the bunker’s gate opened up too close to the baler,” says Himes. “So, the company had two options to fix the situation: install a walking floor, or knock out a portion of the back wall to allow a loader to come through. The company eventually installed a garage door in the back wall which was the cheaper option.”

Other mistakes involve not allowing for enough room around the baler for proper planned maintenance; installing the baler too far from the storage area; and not planning for increased automation, thereby restricting flow of material to the baler.

Redmond from Great Lakes International Recycling points to design errors that might include too much transportation and storage of materials, traffic flows that cross paths, incline conveyors that are so steep that they become unexpected bottlenecks, and having inconsistent and unmanageable burden depths on sort conveyors.

“Consistent feed provides consistent bales,” adds Harris Waste Management Group Inc. vice president Jim Jagou regarding the importance of good conveying systems. “Consistent feeding eases automatic operation.”

Redmond notes that special attention should be paid to bottlenecks, because they determine the actual capacity of the system. “Often, the baler is not the bottleneck, but rather it is the feed conveyor,” he says. “When designing a new system in an existing building, these concerns must be balanced with the existing building’s layout, the capital budget for making changes to the building and compromises must be made.”

FERROUS CONSIDERATIONS

While most balers are inside, there are some that are normally found outside, such as ferrous balers and shear balers. Positioning of a stationary baler outside is just as important as inside because you want to minimize material handling and maximize output. Outside there is more flexibility because mobile cranes can maneuver closer to the baler with loads.

The beauty of mobile ferrous balers is that they can be move relatively easily around a large yard, or offsite to where the material is located.

People outside the ferrous industry may question why a recycler would want to bale the hard metal, but insiders will point to all the same reasons why those in the paper, plastic and nonferrous industries bale.

“It’s simple,” says John Sacco, president of Sierra International Machinery, Bakersfield, Calif. “Baling is needed in the ferrous scrap processing industry to maximize density of loads. Also, a lot of consumers prefer bales and many won’t accept material that is loose. Finally, baled ferrous is easier to handle.”

Ferrous scrap processors may also want to consider a shear/baler that gives them another option for processing. These combo machines also can reduce capital costs instead of buying two separate pieces of equipment.

SIZE COUNTS

The logistics of baling should also include an emphasis on the size of the bale because of shipping concerns. One advantage single-ram extrusion balers have had over two-ram models in the past is that the single ram can easily customize bale length, and bales can be tied off when the material runs out, or when there’s a changeout of material. But newer two-ram models have added a door feature near the ejection nozzle that can clamp the bale before it is pushed out so that more material can be added to the bale, or close off the bale so that different material can be processed behind it.

Bale size is important because the recycler needs to maximize shipping loads. “If you are loading an overseas container the length needs to be a multiple of five feet, whereas if you are loading a truck the multiple is typically six feet,” says Michael Lockman, president of Scanrec, Inc., Waco, Texas. Scanrec (formerly Presona, Inc.) is the North American Subsidiary of the Scanrec (Scandinavian Recycling), AB Group of Sweden.

In ferrous baling, the normal bale size is a 24-inch cube and loading is usually in a rail car. Besides the benefits listed earlier, another benefit in loading baled ferrous is that there is less of a chance of material being left in the railcar.

STORAGE TIME

The ups and downs of the secondary commodity markets have forced even the most die-hard recycling “purists” to rethink their position of storage. “I was one of those people,” says Ron Winter, CEO of Raff Recycling International, Inc., Cape May Court House, N.J. “I used to think that my job as a recycler was to process the material and move it out, but through the years I have changed my viewpoint. Today, if you do not have the capacity to store your material after it is baled then you are basically held at gunpoint.

“There aren’t any contracts that I know of that guarantee the movement of material,” he continues, “So, when you are considering processing material or installing a new baler, make sure you allow for short-to-intermediate storage capacity – about two to four months. This helps you stay competitive, and to gain an edge in some instances.”

Winter warns that recyclers have to also be careful concerning their costs to warehouse versus waiting for a price increase. “You have to make sure you know what those costs are so that you know what risks your are taking. It probably won’t make sense to store baled material if you only expect to get a few pennies more per ton.”