At 35,000 acres, the Denver International Airport (DIA) is the largest airport site in North America — and the second largest in the world, with more than 53 million passengers traveling through the airport annually. With volume like that, it’s easy to understand why the airport’s HVAC filtration system is so important.

Yet, by 2009 the system had become an inefficient patchwork of solutions that required frequent attention from the maintenance department. In addition to needing its more than 3,000 filters changed out approximately eight times per year, which works out to about 24,000 filters annually, the existing system also demanded a lot of energy to operate.

So, the DIA put out a call for a standardized HVAC filtration solution that could help it reduce its labor costs as well as the material waste generated by such frequent filter changes. The facility staff also hoped to reduce the energy consumption of its HVAC system while at the same time improving or maintaining the particle capture efficiency of its filters.

Time to Upgrade

Byron Gustafson, HVAC supervisor at the DIA, said he came up with the idea to change over to the current filtration system while working on his own home.

“I was due to change some filters in my house and found this 3M product,” he said. “I thought, why aren’t we looking into this new technology out here instead of using the technology we’ve been using, which is what was recommended for us 18 years ago?”

In addition to looking for a solution that would improve the airport’s air filtration system while cutting down on labor and energy costs, Gustafson had another prerequisite.

“I was really trying to see if there was new technology out there,” he said. “My biggest thing was, is it an American product? Is it made here in the U.S.?”

Based on the airport’s requests, experts from 3M Purification proposed a solution that could meet each of the facility’s needs by replacing more than 75 percent of the airport’s total filtration system with a standardized MERV 14 high-efficiency 3M filtration system.

3M’s solution standardized the DIA’s filtration system in every concourse and achieved the desired air quality while also substantially reducing energy consumption, labor, and waste disposal. While many areas in the DIA had been using a two-stage filtration system, compounding the labor required for changing the filters, 3M Purification suggested a single-stage system that would standardize applications to MERV 14 particle-capture efficiency and reduce energy consumption. 3M’s longer filter life would also dramatically reduce labor and disposal costs.

The new standardized filtration system resulted in a decrease to the overall pressure drop by approximately 50 percent in addition to a reduction of filter changes by approximately 75 percent per year.

But First, a Test Run

Before implementing a new filtration system, airport staff underwent a lot of research and development. “We have 287 different air handlers out here, so we had to do our due diligence in making sure this product was going to work,” Gustafson said.

Gustafson and 3M Purification began a series of on-site trials that lasted 3 ½ years, with each trial building upon the results of the previous test. Staff used handheld instruments and data-logging equipment to measure the performance of the filters and air handlers, including capturing information on pressure drop, velocity, and particle counts. The final trial saw the installation of sensors that gave the team readouts every 15 minutes for six different air handlers in the concourses.

Once complete, this trial yielded more than 200,000 data points, which showed that 3M’s solution performed well within the DIA’s specifications for pressure drops and would result in significant energy savings for the facility. In addition, the project’s goal of reducing filter changes to every six months was exceeded, and the higher particle capture and unique integrated gasketing of 3M Purification’s filters helped keep the HVAC coils cleaner, which reduced energy costs by improving thermal transfer efficiency.

“With this solution, the DIA has largely standardized its applications,” said Joe Dardis, regional sales manager, 3M Purification. “They’ve gone from using a multitude of different types of filters changed out frequently to a simpler solution using 3M filtration. The standardization has led to the maintenance staff managing filtration replacements based on performance and not a predetermined schedule. This gives them the flexibility to more-efficiently manage the operational and energy costs associated with filtration.”

Recognizing Success

The airport’s achievement was recently recognized by the National Air Filtration Association (NAFA), which included the project in its 2013 Clean Air awards. The awards, which recognize the use of high-efficiency filtration products and good maintenance practices, are presented to organizations and facilities that make outstanding efforts in maintaining a clean and healthy indoor work environment while reducing overall operating costs.

“Denver International Airport is one of the most environmentally friendly airports in the world, and this project helps further decrease the airport’s environmental footprint,” said Dave LaPorte, deputy manager of aviation for airport infrastructure management, DIA. “This new air filtration system not only improved our indoor air quality, but it’s also more efficient, uses less energy, produces less solid waste, and reduces the labor costs associated with maintaining our heating and air system.”

In continuing its mission of promoting sustainability, Julie Smith, media relations director at the DIA, said the airport is committed to finding ways to stand out above other airports.

“We’re always trying to improve the way we do business and use our labor,” she said. “The main thing is being innovative, being that world-class airport. We want to be in front of everybody else, where people want to come to us to get our ideas, and that’s what we’re all about. Investing in sustainability and finding more efficient ways to do things is a primary focus of this airport.”

Legislation Editor Jen Anesi contributed to this article. Information courtesy of 3M Purification.

Publication date: 3/10/2014

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