Pushing sustainability ahead of its time: Pelmar's Peled says rubber goes green for profits

AKRON—Jacob Peled has been lecturing on the importance of sustainability in the tire and rubber industry for four decades, and for a long time, it seems, few accepted what he had to say.

But the founder and executive chairman of Israel-based machinery and services firm Pelmar Engineering Ltd., said that's starting to change, and not necessarily because recycling and pursuing more sustainable solutions is the right thing to do.

"I think it is changing now because sustainability is not something you have to do in order to maintain the cleanliness of our world. It is something that you do now because it increases your profits," Peled said in an address May 14 during the International Tire Exhibition & Conference in Akron.

That trend, he said, started in Europe about 20 years ago, when Pirelli began looking at sustainability as a means to bolstering its bottom line.

"Anything to do with recycling is really sustainability," Peled said. "You have to understand that without it, this world will eventually be destroyed. If we do not learn how to recycle and reuse what we use, the world just doesn't have enough resources to sustain it."

By being in the industry for six decades or so, Peled knows the only subject he really understands is the tire and rubber sector.

While he loves the industry, he also understands the realities of the process itself. Rubber compounds are difficult to destroy, and a tire is meant to be indestructible during the 40,000 or 50,000 miles it spends on the road.

And tires cause a lot of pollution, he said, over their entire life cycle.

"The pollution starts when you compound, when you extrude, when you cure," Peled told the ITEC audience. "Tires are my life, but it is a terribly polluting product. When you produce, it pollutes. When it is used during its life, it pollutes even more."

Studies show that roughly 30 percent of a tire is worn off during its life.

But that material doesn't just disappear. It becomes a powder that goes into the air, into the water, into the soil. Everywhere.

"When the tire dies, it becomes an even worse polluting element, because it cannot be destroyed," the industry veteran said. "It is an indestructible item."

The technology in a tire truly is amazing, according to Peled, but it is incumbent on the industry to be prepared to deal with the tire once its useful life (as it was initially intended) is over.

"We do not expect a tire to be less resilient. We want it to be as resilient as possible," he said. "But while we do that, we need to know how to handle it in the way it will cause the least damage to the universe."

In his opinion, retreading remains the top current option for dealing with scrap tire problems. It sometimes is forgotten, but is an economical and environmentally friendly process, particularly with truck, bus and OTR tires.

The main problem is dealing with the tire carcass once it has run through all of its viable retreading cycles.

Peled believes retreading will remain the most cost-efficient form of tire recycling for the next decade, but that tire pyrolysis is growing in favor and should take over as the top option at some point.

The Pelmar engineer said he predicted two decades ago that pyrolysis would someday rule the tire recycling market. Back then, however, the process wasn't accepted and, in some cases, wasn't legal to use.

Pyrolysis involves heating the tires to a very high temperature in a chamber that is oxygen-free. It starts disintegrating the product into its elements, namely recovered carbon black and tire pyrolysis oil.

The steel industry was using pyrolysis before the tire and rubber industry considered adopting the practice.

"The disadvantages of the system is that it requires a great deal of energy in order to disintegrate into a relatively (useful) product," Peled said. "When it started in the tire and rubber industry, I was already certain that there would be ways to improve it. Indeed, this is what happened."

The pyrolysis that is in use today is a safer, more efficient process that requires less energy and is much more easily controlled—if certain conditions are met.

"The first one is the most important one," Peled said. "If any oxygen leaks into the chamber, it immediately causes an explosion. People have been killed. That is why it became illegal in the United States."

Second is the change from a batch type of pyrolysis—where whole tires are fed into the chamber—to a continuous process that feeds re-shredded tires into the unit, increasing efficiency and reducing costs.

The pyrolysis process now uses lower temperatures, he said, dropping from almost 1,500°C years ago, to less than 600°C today.

Peled added that pyrolysis plants need to be able to process at least 20,000 metric tons of tires a year to be cost-effective.

Another recycling process he touched on is chemical rubber conversion. The system is based on the addition of a special modifier to cured rubber during the process of intensive milling. The heat, combined with the shearing forces and the friction, produces a regenerated rubber compound, which he said can replace virgin rubber at the rate of 20-25 percent of the compound volume.

In some cases, it can replace 100 percent of virgin rubber, and in the tire industry the rate is about 10 percent.

"You obtain rubber, which you can use in any compound. The problem is the shelf life of this rubber that comes out is relatively short," Peled said.

Several companies are working to improve the process, he added, including Green Rubber in Israel.

Looking ahead, Peled said the need to recycle tires will become more acute with the projected sharp increase in the number of electric vehicles on the road. Because EVs are considerably heavier (at present) than ICE vehicles and the torque is considerably higher, the number of scrap tires is projected to spike.

Peled also projects that over the next 10 years recycled carbon black will account for 35-45 percent of the fillers used in the rubber and tire industry.

He said carbon black producers make a good product, but the process of producing it is dirty, and the product itself causes pollution.

"So carbon black, in my opinion, is going to go down even though the tire industry is growing slowly," Peled said.