Ceramic Industry

<strong>KILN CONNECTION</strong>: Silver Bullets, Anyone?

December 1, 2006
Everyone is looking for a silver bullet-that miracle weight loss pill, cold prevention remedy, or special golf swing training aid that makes you drive like Tiger. Most of the time, though, the silver bullet just ends up in your foot instead of helping you achieve your hopes and dreams. Then again, sometimes the silver bullet does exist, and companies occasionally write to me with their versions of what it might be. Two of the most interesting bear further examination.

Everyone is looking for a silver bullet-that miracle weight loss pill, cold prevention remedy, or special golf swing training aid that makes you drive like Tiger. (I have been looking for that one for most of my life!) Most of the time, though, the silver bullet just ends up in your foot instead of helping you achieve your hopes and dreams.

Then again, sometimes the silver bullet does exist, and companies occasionally write to me with their versions of what it might be. Two of the most interesting bear further examination.

Improved Yield

Wes-Co Enterprises has developed a product known as EPS, which may be a real salvation to sanitaryware manufacturers. In most sanitaryware applications, the dried product is placed on StyrofoamTM setting pads when loading the kiln car. Sanitaryware toilets and tanks are heavy and difficult to maneuver into position. The Styrofoam provides a "soft landing" so the ware is not damaged during initial setting.

The solution of one problem often leads to another, however, and this is certainly true here. As the Styrofoam burns in the kiln, it releases volatile gases that condense on the roof of the kiln in the colder areas of the preheating zone. These condensates tend to mix with the chlorides and fluorides emanating from the products being fired to create a greenish-grey goo that coats the kiln crown. From time to time, particles break away from the roof and fall on the glazed ware being fired, creating dirt in the glaze.

The EPS product, marketed under the name Clean Set, claims to have eliminated this kind of dirt defect. While it works like Styrofoam in terms of cushioning the placement of ware, the manufacturer has raised the flashpoint of Clean Set to be several hundred degrees higher than standard Styrofoam. The released volatiles oxidize more fully at this higher temperature, and condensate buildup is reduced or eliminated.

Does it work? At least one of Wes-Co's customers certainly thinks so, and has reported the same. If it works as the company claims, Clean Set may solve an age-old problem and reduce a significant loss category.

Coatings

Refractory coatings have been used in the ceramic industry for quite some time in applications as diverse as parting agents (to eliminate product sticking to supports during firing) and cleanliness (to prevent dirt from the kiln refractories from falling on the ware). When I query my customers about these coatings, I hear mixed results, ranging from "a waste of money" to "a really great product-at least until it fell off of the lining."

Enter Wessex, Inc., a company that has developed a product called Emisshield®. The basis for this material was developed and patented by NASA as a high-emissivity material to be used as a component in heat shields for the X-33 and X-34 supersonic craft. Wessex obtained an exclusive license from NASA to use the material and then continued development for commercial applications.

Initial trial data has been well beyond encouraging with regard to energy savings, which ranges from 10-25%. The company has also solved the adherence problem by using nanotechnology. The system achieves very high emissivity (.93+) from an ultra-thin coating, which Wessex claims does not flake or wear off. The fuel saving comes from a combination of high emissivity and porosity reduction of the hot face lining.

Does it work? A certified trial is planned shortly, with accurate energy measurement before and after the coating is applied. Stay tuned, because yours truly will be running the trial and collecting the data. This product may give manufacturers some much-needed relief from energy costs.

For additional information about these products, e-mail jhagerty@wes-co.com at Wes-Co Enterprises or kelsi@wessexinc.com.

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