Reclaim, Reactivate, Revolutionize: How the BRS-1 Turns Bentonite Waste into Casting “Gold”

Modern Casting September 2025-

BRS Many foundries rely on bentonite as a bonding agent for green sand casting, but the process often results in significant material loss. On average, 45%-50% of bond material ends up discarded. And with material costs on the rise, the persistent waste can have a major effect on operating margins and disposal cost.

For Mark Pine, it also created an opportunity. What if there was a way to minimize the waste and lower overall costs associated with procurement of bonding materials, specifically bentonite?

Enter the BRS-1, a novel recovery system that reclaims and reactivates bentonite dust, resulting in a finished slurry that can be reused in green sand molds.

FROM IDEA TO INNOVATION

When hydrated, bentonite swells and forms a gel-like matrix that binds sand particles, delivering the plasticity, strength, and thermal stability required for high-quality castings. That makes it an ideal material input for green sand foundries.

But the cost of bentonite has quadrupled since the early 2000s, according to Pine, and freight costs to get the material from Wyoming continue to climb, as well. As a result, foundries are experiencing a higher cost burden at the input stage.

They’re also dealing with higher costs on the disposal side. During mulling, the bonding agent absorbs water and disperses throughout the sand matrix. however, during casting and shakeout, fine bentonite particles are lost as dust- along with carbon and other particles.

“Dust is often more expensive to dispose of than sand,” Pine noted, so the ability to reclaim and reuse it is an attractive endeavor.”

Pine began drafting the patent for the BRS-1 in 2016, but he quickly became overwhelmed by the process. “It is not at all straightforward,” he said.

He reached out to John Kurtz at Kurtz Bros., an expert in waste-to-reuse systems with prior patent experience. Together they formed KB Foundry Services LLC and finished the patent application in 2018. Sinto, where Pine works as a regional sales manager, joined the partnership in 2022.

HOW IT WORKS

Unlike traditional rinsing methods, the BRS-1 provides a clear separation of bentonite and carbon, according to Pine. It achieves this through a hydracycle process that separates the dust by density. The recovered bentonite is then mixed with water and blended into a slurry tailored to each foundry’s specifications, ready for reintroduction into the sand system.

The idea of using slurry to make green sand molds isn’t a new idea. Both Ford and GM have used slurry systems going back to the 1960s, Pine said. The slurry-based molds allowed for smooth finishes and better accuracy, which reduced the post-production for finished components.

Pine’s designs was also inspired by systems already in use int he mining and extraction industry.

AT A GLANCE

Features include:

Flooded-suction pump, which ensures consistent head pressure critical for slurry movement and separation
Hydracyclones (centrifugal separators) that classify particles by density and size
Automated controls, minimizing labor and ensuring consistent output
Compact footprint with an 11×13 ft. base and a 14-ft. height requirement to accommodate the pump. It’s mounted on a skid for easy installation.

Pine wanted the system to be accessible and efficient for a broad range of operators, which is why having a small footprint was crucial. Installation also is straightforward, through proximity to the dust source improves efficiency, he said.

Since the patent was completed, not much changed throughout the entire design and production process, with one exception.

“We recognized that it had to be labor- free and able to run by itself all day,” Pine said about the addition of automation.

Otherwise, the process was much smoother than expected.

“We thought we’d be zigging and zagging, but it did what we wanted it to do pretty much right away, ” he said. That doesn’t mean additional improvements aren’t on the table. Ultimately, Pine would like to develop a way to replace the additional water reeded for processing to make the system even more economical and environmentally friendly.

EXPANDING THE FIELD

According to the spec sheet from Sinto America, the recovery system can reclaim up to 90% of active clay and can process up to one ton of dust each hour. Many operators report reducing bond purchases by 35%-40% with the system in place. In addition, the mulling process is shortened because the bentonite fully hydrated, reducing cycle time and energy consumption.

But the benefits aren’t just in the economics. “It also makes better sand, and that means better casting,” Pine said. “Green compression strength, hot strength, dry strength…every property is enhanced.”

While the current price point- between $300,000 and $400,000- may be out of reach for smaller foundries, Pine is exploring regional processing centers. Foundries could send their dust to KB for reclamation and receive slurry in return.

Sinto holds exclusive rights to manufacture and sell the BRS-1 in the U.S. Pine also filed for a European patent, where high disposal costs make the technology especially attractive.

“It took time to get acceptance in the U.S.,” Pine admitted. “Every foundry already has a quality manager who’s spent years developing their sand systems. So they look at this and say, “You’re not going to mess with it.”

One of the selling points for hesitant operators, however, is the ability to accommodate the sand mixes already in use at the foundries. That allows for system to be plug-and-play, Pine said. “We’ve never once had to change their mix.”

Although currently designed specifically for green sand operations, Pine says he’s exploring ways to expand the types of foundries where the system can be implemented.

“I have lots of ideas floating around in the my head,” he said with a laugh.

The BRS-1 system represents more than just a clever workaround for bentonite loss- it’s a strategic leap toward sustainable, cost-effective casting. Pine’s vision, rooted in practical experience and shaped by industry collaboration, has yield a solution that’s both technically sound and economically compelling, proving that innovation often begins with a single question: What if we didn’t have to waste so much?