Kleinfelder - Salt Lake Valley Solid Waste Management Facility

Salt Lake Valley Solid Waste Management Facility

Salt Lake City Corporation
Salt Lake City, Utah

Project Description:

Kleinfelder has been developing a landfill gas collection and control system (GCCS) to harness the energy of landfill gas, at least enough to power approximately 2,000 nearby homes starting this winter. Byline 2: Installation of 11 custom replacement gas condensate knockout units and other system enhancements will enable the Salt Lake Valley Solid Waste Management Facility to produce and sell energy from landfill gas starting this winter.

For 15 years Kleinfelder has provided ongoing environmental support services at the Salt Lake Valley Solid Waste Management Facility, the largest Class I municipal solid waste landfill in the Intermountain West. This region includes the area bordered by the Rocky Mountains, Sierra Nevada and Cascade mountains, southern Canada, and northern New Mexico and Arizona. The facility receives more than 2,300 tons of spent fruit, shoes and other municipal solid waste (MSW) per day, or about 700,000 tons per year.

The facility was the first in EPA Region 8 required to install gas emission controls to comply with federal New Source Performance Standards (NSPS) for landfills. The GCCS, with 38 vertical and horizontal gas extraction wells and piping, has nearly 40,000 linear feet of buried gas-extracting pipelines within the landfill. Although the GCCS was designed foremost for regulatory compliance, facility managers soon realized that a viable renewable energy project lurked in the trash.

In 2004, the facility’s managers requested Kleinfelder to design and install 11 replacement gas condensate knockout units on the main gas header pipeline to optimize the system for energy development. Benefits included the ability to better remove voluminous condensate from the gas stream for improved methane quality and flow consistency.

In conjunction with facility managers, DTE Biomass Energy, and Salt Lake City engineers, Kleinfelder developed a new design for the condensate knockout units and oversaw the custom fabrication and delivery of the units to the site. Kleinfelder technicians and earthwork contractors also installed the units.

Challenges for the project team included below-freezing wintry weather and regulatory obstacles, including restrictive air quality regulations that prohibited shutting down the existing collection system for more than five days. (If the five-day limit were exceeded, the facility would be in a compliance violation and related fines would have been levied.) But the team overcame this regulatory hurdle after researching state statutory law and finding little-used discretionary provisions that the environmental regulatory authority agreed to.

Following this agreement, Kleinfelder completed the retrofit in January 2005, dramatically increasing the GCCS operating efficiency. Methane quality of the gas rose from 40% to 50%, while the flow increased from approximately 750 cubic feet per minute to approximately 900. These numbers remained consistent and stable in the months that followed, giving landfill managers the confidence to execute a contract with a gas-to-energy vendor to develop the site.

Currently, three large engines are being installed on the site to burn landfill gas to generate electrical power. Uplinked into the electrical grid, the site will begin producing approximately 3 megawatts of electricity in late 2005, enough to power more than 2,000 area households.

“We now have a gas collection system that operates without interruption,” said Dan Bauer, associate director, Salt Lake Valley Solid Waste Management Facility. “Before, we had to worry about keeping the system up and running. Now we just keep an eye on the methane quality and total volume.Everyone here is pleased that the new knockouts have dramatically improved the viability of our as-to-energy project. The proof definitely is in the pudding!”

The benefits of this project are substantial to the end-users and the environment. Prior to the GCCS, methane-laden landfill gas simply migrated through the landfill cover into the atmosphere where, as a precursor to low-level ozone, it can create serious local health problems. In addition, methane is a potent greenhouse gas that contributes greatly to global warming.

By burning the gas to generate electricity, the project directly prevents more than 6,000 tons of methane per year from entering the atmosphere, and eliminates the need to generate electrical power elsewhere. According to EPA calculations, the emissions removed from the environment by this project will be equivalent to offsetting the use of 645 railcars full of coal, or removing the emissions from 25,200 automobiles.

Now that the gas is collected actively, and soon will be burned to create energy, a truly renewable energy resource will be utilized. And because the landfill is beyond 40 years from closure, it will provide a dependable, expanding source of gas for the landfill and the local electrical utility for the next several decades.