MRF Operations Forum 2024: Managing the tipping floor

As the drop-off point for incoming residential and commercial truckloads, the tipping floor at a material recovery facility (MRF) can be an action-packed space.

Depending on the facilities, tipping floors can vary in size and receive a diverse array of materials—including numerous items that could be considered contamination or hazardous—each day. According to a panel of waste and recycling industry experts who spoke at the MRF Operations Forum in Chicago in October, there are ways to ensure smooth operation on a MRF’s front end, whether it’s the equipment used to move material or the training and positioning of employees to efficiently run shifts and even aid in fire suppression if the need arises.

During the Best Management Practices For What’s Coming Off The Tipping Floor session at the annual show hosted by Recycling Today Events, Jim Marcinko, director of recycling operations at Houston-based WM, said traffic is the biggest pressure point when it comes to a tipping floor.

“You want to safely get the truck in and get them out of the facility and, at the same time, when they tip, you’ve got to be able to see the material and address the material,” said Marcinko, who oversees about 50 facilities in the southern U.S. "You look for any gross hazards or things like that before it goes into the pile.”

Shift solutions

With loads of material arriving at a facility during certain times, the positioning of staff can differ depending on the shift.

Session moderator Nat Egosi, president of Melville, New York-based RRT Design & Construction, posed the question of what a MRF running two shifts could do when most of the material was being tipped during first shift hours and what pressure there might be to have material available for the second shift to load into the system.

“You’ll staff differently during the day,” Marcinko said. “Maybe you’ll have somebody who’s focused on loading the system versus somebody who’s focused on managing material and mixing things, where at night you’re just going to be loading the system in from the bulk material. But you’ve got to make sure that it’s all positioned correctly. You don’t want to push [material] to the wrong side of the floor or vice versa.”

Tom Ferretti, the senior vice president of operations at Austin, Texas-based Balcones Recycling, used the company’s MRF in Brooklyn, New York, as an example. The facility operates with three shifts, receiving material 24/7, and can have as many as six or seven trucks unloading at a time.

The MRF runs two shifts focused on moving material once it’s dumped, while the third shift performs maintenance in addition receiving material.

“We run the two shifts, run down the material, make sure we have enough room and always have a Plan B for a breakdown or if something unexpected happens, to ensure that we can [continue] to consume,” Ferretti said. “There’s some maintenance [performed] on our third shift, so we run down our tip floors towards the end of the night for fire hazards, dump our bunkers and that’s part of the management of the material coming in.”

Ferretti said the MRF takes steps to keep its people and loading equipment safe and ensure a clear operating path.

“We actually make a movable wall with our material,” he said. “As the tip floor grows and shrinks, our loader operators or crane operators are trained to put a 4-foot wall of our inbound material between the equipment and the trucks and people. You can’t have a fixed wall because the floor always swells and contracts. It’s just a safety precaution at the end of the day. We shrink our tonnage, dump our bunkers, protect ourselves from fires and then go on with our maintenance.”

Equipment considerations

Depending on the single-stream recyclables hitting the tip floor, the equipment used to load the infeed conveyors or drum feeders in a MRF system can vary.

Ferretti said Balcones’ MRFs in the eastern U.S., all located near waterways, use cranes to unload barges, and that equipment also has made a difference on the Brooklyn facility’s tipping floor.

“The pro of a crane is you can kind of cherry pick your infeed,” he said. “This time of year, [for example,] we get more plow blades and chains from the [New York] department of sanitation than we know what to do with. And if you put a 12-foot hardened steel plow blade through your system, it opens up a conveyor like a tuna can.

“We run 65 to 70 tons an hour in our Brooklyn facility, about 1,400 to 1,500 tons a day. And if you have a crane, know your material. Is it 350, 400 tons per cubic yard? You’ve got a 5-yard clamshell [grapple]. We size our equipment to be able to load 30 percent quicker than the consumption of the equipment, so we can catch up. We put a 14-foot bucket on our loader. Our tip floor is only 26,000 square feet, and a crane can pile high.”

Ferretti noted, however, that a crane can be more difficult to procure than a loader in the event of a breakdown, and a loader can move more material than a crane. “A crane can stack material higher, but it has to work harder, the cost is a little more depending on the size, but it’s good if you’re cherry-picking material and it’s stationary. Keep it where it needs to be, cherry pick [material], but also know you’re not saving on it because a loader still has to feed the crane.”

Marcinko said he would choose a crane or material handler with a grapple for his facilities, though that isn’t suitable for every location.

“If you have a lot of volume and you can afford to have multiple pieces of equipment out there, that’s great,” he said. “If you have a plant that has 2,000 tons a month and you can afford one loader operator, that’s what you’re going to have. But a crane or excavator can move so much more material efficiently. You can pick through the material.

Marcinko added that there could be resistance at a facility when changing from primarily using a loader to using an excavator because of the more challenging training process, though positive results could come in time.

“You bring in this new piece of equipment, and for the first two weeks or three weeks, as they learn how to effectively move it, where to position it and how to pick and store [material], all of a sudden, productivity jumps up,” he said. “The quality jumps up. They’re very happy with it at the end, but it’s a bigger learning curve for a facility to transition to one.”

As far as material handler attachments, Ferretti said he uses clamshell grapples for cherry picking material in a tidy fashion. Balcones also uses 2-yard orange peel grapples, which he said are preferable for feeding the MRF system, though they don’t “clean the floor” as well as a loader.

Dealing with contaminants

Whether it arrives loose or in a bag, contamination remains troublesome for MRFs of all sizes.

Todd Hubbard, vice president of recycling at Phoenix-based Leadpoint, said his sorters are trained to simply throw out any bag they can’t see inside.

“I’ve seen it way too many times over the years where somebody rips a bag open and lets three other things get by that could screw up a screen or optical belt,” Hubbard said. “If they can see through the bag, they can rip it open if they have time.”

He noted, however, that such a practice depends on how much time the sorters have. “If the belt is stacked up and they’ve got to look at a bag versus grabbing a pallet or washing machine or whatever may be coming up there, [I’d say] throw away the bag, go after the big piece and get it off before they have to stop [the system].”

As a way to help mitigate incoming contamination, Marcinko said WM began deploying camera technology in its trucks two years ago that notifies the company when potentially dangerous contamination is collected, allowing it to correct that disposal behavior. Additionally, WM has camera systems at some of its facilities that can look at individual loads.

“We can take that [data] back to the route managers through the billing systems and say we need to get this information back to the customer,” he said. “We can help our route managers understand it, but we have to eventually get to the customer because the manager didn’t put [the material] in the bin, the customer did.”

Marcinko, Hubbard and Ferrett said they all perform material audits to get a better idea of what’s in their streams, then communicate that information back to route managers or municipalities they work with. Ferretti said, however, that it’s unlikely a facility will be able to get all contaminants out of the stream.

“You hope to get the hazardous stuff out,” he said. “You do look for batteries. You look for anything that could be dangerous, like a container or a bicycle frame or something that could damage your equipment. We prioritize what we’re looking for and then spread it out, take pictures and get them back to the municipality. We’ll put an emphasis on it for a week [at the MRF]. If you get a bicycle frame in and they jam something up, let’s work on that.”

Managing facility fires

Fires are a concern for every recycling facility, and each panelist described his company’s process for suppressing them and making sure employees safely evacuate.

Hubbard said Leadpoint uses a “fire brigade” system, where operational leads and lockout/tagout personnel are tasked with making sure employees safely exit the building and sign in at designated gathering spots, then decide on whether to attempt to suppress the fire themselves using extinguishers or hoses or wait for the local fire department to put out a blaze.

“We have our onsite manager and our leads out on the system,” Hubbard said. “We like to use air horns, and they have two different signals. One means attention, basically. Something’s going on and everyone’s going to look. If that horn’s going full blast and it keeps going, [it means] get out.”

In the event of a fire, Ferretti said Balcones employees are trained in their facility’s egress plans and are expected to move to a designated gathering point, while mechanics are trained to use extinguishers. At the Brooklyn MRF, for example, he said the company developed its own deluge system and placed it in strategic areas so mechanics wouldn’t have to wrestle hoses from the ground.

“We made it where we can’t stop what’s coming in, but we can make it a safer first response by putting deluge systems in specific areas where everyone has a specific role, like who goes to the ball valve, who connects it, who’s up at the leading pipe of a pipe system, and then put [the fire] out,” he said. “It’s very choreographed, everyone has a place. We have mock fire drills where we do more than just get people through an egress. We have our mechanics drill so they know their place.”

Ferretti said his mechanics carry radios and are trained on where to go in the event of a fire, whether it’s the tip floor, infeed or shredder, for example, on all shifts.

Marcinko said WM trains all MRF employees on fire suppression, and company facilities are equipped with deluge systems similar to what Ferretti described. Those deluge systems are placed in strategic areas such as bunkers and screens, where masses of material susceptible to igniting typically are located.

“They all know how to use fire extinguishers, and it’s important to maintain them,” Marcinko said. “And if they’re new employees, that’s one of the biggest trainings.”

Marcinko added that there’s a fine line between responding to a fire and pretending to be a fireman, though.

“The firemen are going to do what they need to do to put the fire out,” he said. “We want to make sure our people get out of the building, get out safely and it’s under control. … You’ve got to prepare for fires, because they’re going to happen.”