The Baltimore Sun is the major daily newspaper for the greater Baltimore metropolitan area, boasting a circulation of more than 400,000. Housed in a 250,000-sq-ft facility known as Sun Park, the newspaper maintains its industrial packaging machinery and four enormous printing presses. Conveniently located near I-95, just south of Camden Yards, the facility prints, packages, and distributes both the daily and the Sunday editions. The Baltimore Sun's main editorial offices are located in downtown Baltimore on Calvert Street.

Humidification is Key

Proper humidification is critical to the success of any printing operation. Therefore, humidity control on the pressroom floor plays an important role in the overall quality of the newspaper product. In order to maintain proper humidification for The Baltimore Sun, Herrmidifier¨ (Sanford, NC) was asked to redesign and install an integrated humidification system - one that could handle the plant's immense space.

When officials at Sun Park first began seeking an effective humidification system, they looked for a system that would provide the best conditioned air for their product. The responsibility of finding such a system was not an easy task. Vincent J. Rose, engineering supervisor at Sun Park, worked with system engineers and several air conditioning specialists to determine the best possible solution.

The number-one issue for Sun Park's humidification system was reliability. First, the facility maintains an enormous space, with the pressroom alone housing four Goss Color Liner presses. Each press can hold 12 press units for a total of 48 units. Next, the humidification design needed to accommodate an air circulation system handling approximately 500,000 cfm in the pressroom and an additional 120,000 cfm in the packaging room. This translated into a humidification load of 5,600 lbs/hr.

Overall, the most critical requirement of the humidification system was the ability to maintain an average rh of 50% in all of the printing press areas. If conditions in the pressroom are too dry, newsprint has a propensity to stick together when feeding through the press. Many problems such a web break, running breaks, and paster breaks can result if proper humidity is not maintained at all times. In addition, the humidification units need to control static electricity during all press runs and work seamlessly with the air circulation system. Effective filtration of the interior air for ink particles and paper dust is critical for proper air circulation.

Phasing in the Changes

When Sun Park became operational in 1991, the humidification system development was divided into three phases, each phase leading to a more comprehensive and efficient humidification system. In phase one, a competitive company had been contracted for The Baltimore Sun by a third-party vendor. Officials at Sun Park soon realized this system was not meeting the precise demands that the press load required. It simply could not supply the correct amount of moisture. Vince Rose witnessed its failure firsthand.

"The quality of the product could not accommodate our demands," said Rose. "The system didn't modulate correctly or perform up to its own specifications. It became increasingly clear that we needed another, more reliable system."

As phase two of the humidification process approached, Rose and officials at Sun Park began seeking other vendors for alternative solutions as well as possible extensions to their current supplier's product line. They eventually selected Herrmidifier, a company known for the Herrmidicoolª system, a unique, in-duct, air-water atomization technology.

Designed to be energy efficient and easy-to-install, Herrmidicool systems incorporate a control technique that monitors humidity and supply-duct conditions for accurate modulation in even the most precise environments.

The technology utilizes an automatic, fully modulating control system that permits the self-cleaning and self-sealing atomizing spray head to operate within a 30-to-1 turndown ratio. These features give Herrmidicool systems the ability to provide control over interior atmospheric conditions in a variety of manufacturing, laboratory, and commercial building applications. Sun Park is a prime example of the system's manufacturing application capabilities.

Hot Off the Press: Great Results

After the first season of operation, Herrmidicool's system performance was found to be outstanding by the administration as well as the maintenance staff. When phase three began, The Baltimore Sun decided to decommission its old humidification system in favor of another Herrmidifier Herrmidicool system. With a total of eight air handlers, each maintaining 60,000 cfm, Herrmidicool is now the sole humidification system at Sun Park.

"From startup," says Rose, "this system exceeded our expectations. The structure and makeup of the product line even allowed us to change some of the initial system parameters. It allowed us to experiment with different settings for other modes of operation and has provided a major cost savings for us."

Today, Sun Park maintains its humidity output at the very limit of its space capacity. By doing so, they are able to gain five additional degrees of cooling throughout the plant. On moderate days in the early spring or late fall, Sun Park actually saves money on its mechanical cooling costs during short to moderate production runs.