Budd Inlet Wastewater Treatment Plant Cogeneration Facility
HDR provided permitting support, alternative funding support, design engineering and construction support services for a 335 kW digester-gas fueled congeneration system at the Budd Inlet wastewater treatment plant for the LOTT Alliance (cities of Lacey, Olympia and Tumwater, and Thurston County).
Using the Design-Build alternative delivery method, the project was installed in just under a year, meeting a deadline for significant funding from Puget Sound Energy which provided 70 percent of project costs, and minimizing disruptions at the plant.
The first phase of the project included analysis of digester gas production rates and gas quality, plant heat needs and electrical demands, and development of conceptual plans to support the Guaranteed Maximum Price. Gas production was carefully calculated, including storage capacity of the existing floating cover digesters to optimize engine sizing, thereby reducing life-cycle costs.
To satisfy plant needs while meeting fuel treatment performance requirements, workshops were held with plant staff to discuss the pros and cons of different gas treatment technologies, including sessions with technology vendors.
The second phase involved finalizing equipment selection and construction document preparation to provide a new digester gas treatment system, 335 kW reciprocating engine-generator, heat recovery systems for the engine package, two hot water boilers, associated piping, valving, and controls.
The Design-Build of the new cogeneration facility was a critical component to the mechanical systems of a new administration building and its ability to achieve LEED status due to heating and energy from a renewable resource. Construction was completed in November 2009.