A manufacturer of light bulbs experienced a real savings of $120,000 per year on a capital investment of $11,000, achieving full payback in just 33 days.
Every light bulb in your home or office is most likely manufactured at the same glass plant located in central Kentucky. Nearly 10 percent of all the glass used to supply the world’s incandescent light bulb needs is manufactured at this one location. In addition to these bulbs, the plant makes borosilicate hard glass for spotlight lenses and reflectors, as well as lead glass parts used in the manufacture of fluorescent tubes.
Sand from a Tennessee mine is the main raw ingredient used at the facility. Furnaces must reach temperatures in excess of 4,000 F to melt the sand. Other additives, such as sodium oxide, dolomitic limestone, lead, and boron, are added to this molten silica to produce the three specific types of glass used at this location.
Process Difficulty
Glass plants use enormous amounts of water in their processes. This facility had tried recycling water in the past, but ran into great difficulties. Heat exchangers would plug, cooling jackets would clog with debris, and instruments used to detect the level of molten glass in furnaces would overheat when cooling water lines choked off. Production decreased, wastage increased, and costly labor ran rampant.
As a result, the facility was forced to release potable water to the environment through a permitted discharge after just one pass through the manufacturing process. However, when this route was taken, purchased water consumption immediately doubled. Nearly a quarter of a million dollars a year was being spent on water alone.
Finding a Solution
Resident engineers began focusing on the problem. After evaluating a number of alternatives, Tom Broderick, the plant’s maintenance manager, decided to install automatic self-cleaning screen filters in the pump house to remove sediments and suspended solids from the detention pond near the offsite discharge. This filtered recycle water was then sent back to the plant at flowrates varying from 800 to 1,800 GPM for use in cooling vacuum pumps and other on-site uses.
Because the two vertical turbine pumps took up so much space in the pump house, and forklift access was required to periodically pull the pumps, most filters could not fit into the available space. Ultimately, Broderick chose two Orival Model ORG-060-LS automatic filters for the job. His main reasons for selecting the ORIVAL units were the vertical orientation and the low flow requirement for the self-cleaning process.
"I couldn’t believe that the filters were an in-stock item," says Mr. Broderick. "The vice president of Orival personally inspected the installation, making a few efficiency adjustments to the controls. Our water bill has decreased by $10,000 per month since installing the Orival filters," Broderick says.
John Wynd, engineer for glass operations at the facility, says he is so impressed with the performance of the filters that he plans to install additional units to support another application to further reduce municipal water consumption.
For more information on Orival’s automatic filters, visit www.orival.com.
