Ceramic Industry

SPECIAL SECTION/BRICK & CLAY RECORD: Servicing the Brick Belt

October 31, 2008
A new batching line is providing flexibility and reliability to help Prince Minerals produce high-quality pigment blends for its customers in the Brick Belt.

Each dispenser holds a single ingredient and is modular so it can be easily removed from the line.


Prince Minerals, Inc. is a leading producer of specialty mineral products with an emphasis on naturally occurring minerals and pigment applications. Its products are used in brick, refractories, glass, ceramics, foundries, cement and other applications. The company operates six processing plants, including the newest, a 40,000-square-foot facility in Monroe, N.C., that’s also home to an extensive R&D lab and Technical Service Center. The North Carolina location, which began production in March 2008, was chosen for its close proximity to the company’s growing Brick Belt customer base, which spans from Maryland to Texas.

Two main production “circuits” comprise the Monroe facility. One dedicated line manufactures proprietary through-the-body pigment blends in bulk at a rate of 10 to 15 tons per shift for the clay brick and colored mortar industries. Colorant is stored in silos.

A second commercial line produces specialized dry-mix surface colorants for the structural clay, brick and tile industries. For the design and manufacture of this larger line, Prince Minerals worked with Ingredient Masters of Cincinnati, Ohio. The firm specializes in precision batching systems and has experience in the brick (Redland Brick), ceramic (Oceanside Glasstile), refractories (Uni-Ref, Spar Refractories, Zedmark) and colorant (Englehard) industries.

Establishing Goals

Jon Attridge, Prince Minerals’ construction facility manager, led the team that developed the requirements for the line. For the 10 years that Attridge has been with Prince Minerals, his area of specialty has been colorants for the brick industry. “I’m an R&D guy, a ceramic engineer whose focus is colorant development,” he says.

The goal for the commercial circuit, according to Attridge, was to build “a flexible batching line that would produce consistently high-quality product with virtually zero rework. We also wanted to optimize the ergonomics of the operation by eliminating manual tasks, such as bag cutting, and have the cleanest possible work environment by preventing material from becoming airborne when dispensed. Finally, we looked for a system concept that was industrial, rather than food-grade or something else, and a supplier with an understanding of the industrial environment.”

System Details

After substantial research and consideration of the approaches of several batching system manufacturers, Prince Minerals chose the system concept recommended by Ingredient Masters. The heart of this system is a sequence of 54-cu-ft polyethylene dispensers, each with a bulk bag lifting frame. The dispensers are arranged in facing rows of a dozen each and have a common support structure and dust pickup system.

Each dispenser holds a single ingredient and is modular so it can be easily removed from the line. Bulk bags-Super Sacks-of raw material are suspended above the bins at a 12-ft elevation. Beneath the bins, an operator-driven, motorized scale cart moves on a track. Ingredients, target weight and tote locations applicable to the selected recipe are entered into a program. The cart then moves down the track and the correct proportions of each ingredient are released through a valve into the cart’s hopper. Materials can also be added from Super Sacks or in bulk from an outside silo. Batch accuracy is +.2 lbs.

When the batch is complete, the hopper is retrieved by a forklift and emptied into a mixer. After blending and testing, finished product is conveyed pneumatically to one of the storage silos, then to the bagging facility. Half of the finished product is packaged into 50-lb bags, while the rest is put in bulk bags of 1000 to 2000 lbs.

“We get precise weights into the Super Sacks just by hitting a button and specifying the weight, but that’s not the end of the story,” says Attridge. “There’s still a 24-hour quality control process before batches can be shipped. A master standard has been established for each color blend. Finished products are tested for fired color according to customer firing parameters. Incoming raw materials are subject to quality protocols we developed. In either case, a sample is taken from each batch and tagged for firing and rheological tests.

“Samples are suspended in water, applied to test substrates or tiles, and fired at 1900 to 2000ºF. The next morning, they’re read with a spectrophotometer, which gauges color against the standard. If approved, that batch is released for shipment. If alterations are required, material is returned to the mixer, adjusted for color and rheology, re-sampled, and tested again.”

The system offers flexibility and the ability to automate or expand as needs evolve.

A Flexible Solution

The system engineered for Prince Minerals is a lean manual system that offers flexibility and the ability to automate or expand as needs evolve. “Prince Minerals has a commitment to supply a pre-qualified, pre-checked product,” says Scott Culshaw, president and owner of Ingredient Masters. “They needed to know that when it’s shipped to a customer and fired as designed, it will be accurate to the standard.”

Another advantage of this equipment, according to Culshaw, is that Prince Minerals’ customers “have no need to maintain inventory, but rather just a dozen or so pre-blended formulas.” In addition to the primary production line, Ingredient Masters also supplied equipment for a third line, similar in design, which incorporates three feed hoppers mounted above a 200-cu-ft mixer.

For more information regarding batch handling systems, contact Ingredient Masters at 1080 Nimitzview Dr., Suite 302, Cincinnati, OH 45230; call (513) 231-7432; e-mail sales@ingredientmasters.com; or visit www.ingredientmasters.com. Prince Minerals’ website is located at www.princeminerals.com.

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