“Our product is unique. No one else in North America manufactures a calcium silicate masonry product. We use steam to cure and solidify the stone.

The Clayton generators produce the right kind of steam, which we believe is good for our product.”

Arriscraft stone, prized for its natural beauty, adorns some of North America’s most distinctive homes, commercial buildings, embassies, and professional sports stadiums. Due to its exceptional authenticity, the stone closely resembles quarry stone. The key to Arriscraft’s success lies in its patented Natural Process® technology, which replicates the natural formation of stone in the earth. By combining sustainable, natural raw materials and applying pressure, heat, and time, Arriscraft produces a calcium silicate masonry product virtually indistinguishable from quarry stone.

When Arriscraft began working with Clayton, it sparked a significant transformation in their manufacturing process

Arriscraft, the Stone Products Division of General Shale, is based in Cambridge, Ontario, Canada. It has an additional manufacturing facility in Fort Valley, Georgia, and a dolomitic limestone quarry in Ontario.

When Arriscraft and Clayton first met, Arriscraft was using fire- tube boilers. The company was not only experiencing tremendous energy inefficiency, but their Natural Process® technology required dryer steam than a conventional fire- tube boiler could provide. The fire-tube boilers lacked dedicated steam separators resulting in wet steam, affecting product quality during significant load changes and resulting in product waste. There was also an issue of slow ramp-up/ ramp-down. A fire-tube boiler could take an hour or longer to reach steam pressure because of the sheer volume of water in it, so it couldn’t respond quickly to changing loads. There were also other underlying factors adversely affecting their boiler performance, therefore, Arriscraft quickly identified a need for an improved boiler solution The need for a completely different steam solution was obvious.

Switching to Clayton steam generators was pivotal for Arriscraft.

The decision was made to switch from the conventional fire-tube boilers to Clayton steam generators, which would address virtually every issue Arriscraft was experiencing. However, what clinched the decision was the ability

of Clayton steam generators to fire up and down quickly, largely due to the low water volume. According to Tony Shaughnessy, who joined the company as the Director of Engineering shortly after the switch was made, “The Clayton generators go from a cold start to full output fairly quickly, maybe 5 minutes, and go from producing very little steam to producing a lot of steam as needed.” Arriscraft runs its stone in autoclave cycles. Depending on what products they’re making, it might take an hour or more to load an autoclave with stone. Then, the autoclave is pressurized with steam to a predetermined rate when the door is closed. That rate must be maintained because, as Tony explained, the product they start with is “like a sandcastle.” If it gets too wet before the temperature rises, it can solidify and become mush, leading to product loss, so maintaining that pressure ramp in the first half hour of the cycle is vital to the Arriscraft process.

Ron said that according to experts a typical economizer increases efficiency by 3-4%, and the resulting energy savings would be even higher. “People often see a 5% increase in efficiency and think they’ll save 5% on fuel bills. But a 5% increase in efficiency can actually reduce your fuel bill by over 6%.”   Fast forward. After more than 22 years of reliable service from Clayton generators, Arriscraft recognized the need to upgrade.

During a visit to the Arriscraft plant at the Fort Valley location, Will Brozowski, Clayton’s Senior Sales Engineer – Southeast, observed a significant amount of steam venting through their exterior atmospheric hotwell, which meant energy was being wasted. The 22 years had taken a toll.

“Our older Clayton boilers were needing more maintenance, and parts were getting harder to find,” noted Gregory Callahan, Plant Manager at Fort Valley. “We wanted to upgrade to newer, more efficient equipment.”

Gregory and Tony liked their Clayton model, so they wanted to look at the newer version. Ron Polidori, Clayton’s sales manager in Canada, knew

their business well and helped them select some of the control and energy efficiency options they could get with the newer 300 BHP Clayton boiler Model EOG 304.

Economizers to improve energy efficiency

Economizers capture waste heat from the boiler exhaust and utilize it to preheat the water entering the boiler, reducing the energy required to produce steam. An economizer preheats the water entering the boiler so less energy is required to produce the same amount of steam. Without the economizer, the flue gases would be released from the boiler into the atmosphere, where energy would be wasted.

“The new models have better controls – with variable speed, better water control than the earlier Clayton models we replaced,” Shaughnessy said. “Now, we don’t need to run as much boiler to get the same output.”

A steam separator that delivers a 99.5% dry saturated steam

The new Clayton steam generators are designed with a dedicated steam separator that guarantees 99.5% dry saturated steam. Dry steam is crucial for manufacturing the company’s calcium silicate masonry products.

Linkage-less combustion controls that increase efficiency by another 3-5%*

The earlier boilers utilized a linkage combustion control system, which involved linkages, potentiometers, and other moving parts to modulate the burner, air, and gas. Over time, these linkages would go out of calibration, reducing efficiency due to suboptimal combustion settings. With the linkage-less controls on the new models, these problems are virtually eliminated.

*Industry experts believe overall efficiency is increased again by at least 3-5%.

Arriscraft is on the verge of realizing its goal: acquiring three new state-of-the-art Clayton steam generators over a 3-year period to replace the four older Clayton models

Tony confirmed the upgrade was a good move. “We did this to take advantage of the benefits of the newer Clayton design – the variable speed drives on the pumps and the improvements with the controls.

Even though they’re nominally the same size boilers, 300 BHP, we find that we get more steam out of the new EOG 304s. That’s enabled us to reduce the number of generators we need from four to three.”

While upgrading to the new steam generators is a sizable investment, the returns are already apparent – including a 25% reduction in energy costs

The project was strategically spread over three years to manage costs, with one unit still left to replace on-site. Although it will take time before the significant savings are realized, there are already visible results.

• Significant energy savings. Although they used an atmospheric feedwater tank on their previous Clayton boilers, Arriscraft decided on a pressurized deaerator for their new boiler system. The new deaerator offered numerous operational benefits that resulted in significant yearly savings.
• Fewer breakdowns and improved performance.
• Lower yearly chemical costs. The pressurized feedwater system (deaerator) eliminated continuous venting and dissolved oxygen in their feedwater, reducing the cost of adding an Oxygen Scavenger to their chemical treatment program.
• Clayton’s steam generators are classified as low-volume water tube boilers, so Arriscraft is spared the expense of employing a certified operating engineer as required by local regulations if conventional fire-tube boilers are used. Tony noted that their system uses both a feedwater tank and a de-aerator, so the condensate returns go to the feedwater tank and then to the deaerator.
• Reduced cycle times and increased productivity. The improved systems and technology have reduced autoclave cycle times and minimized water waste from wet steam to nearly zero.

“Regarding the savings with the deaerator versus a feed water tank: The steam is distributed at a high pressure to the auto- clave, and as the steam goes through the system and gives off its heat, it begins to condense, and that returns back to a feed water tank – or in the case of the new boil- ers, to a deaerator, which is a reservoir or storage component to feed the boilers with the water that they require.”

Why Arriscraft continues to choose Clayton Industries’ technology

All one would have to do is look at Arriscraft’s P&L to realize the monetary effect that switching to Clayton boilers has had on the company. But stepping away from the spreadsheets and into the plant, the proof is just as telling. Improved production rates, lower energy requirements, less product waste, fewer breakdowns, and a safer environment all leave clues.

Ultimately, the customer is happy with both the equipment and the team from Clayton.

“Ron knew exactly what we needed,” said Greg. “This was the perk of continuing to work with Clayton.

They knew what the issue was and how to upgrade it to contemporary technology. We were able to go from four smaller, less efficient boilers to three more modern Clayton boilers.”

Tony added, “We stay with Clayton because we have a good relationship with them. We know that their equipment is reliable and works

for our process. So really, it was the history that we’ve had with Clayton, in terms of reliability and our relationship with their service team.”