Oklahoma State University decommissioned its central utility plant, built in 1948, and built a new one to serve its growing thermal utility loads on campus. Our team provided mechanical, electrical, plumbing, structural and civil design for the utility distribution system connecting the plant to the campus. We were also the owner’s engineer reviewing the new plant design and provided commissioning (Cx) services for the project.
The plant provides the campus with 12,000 tons of chilled water capacity via three variable speed electric centrifugal chillers and 220,000 pounds per hour of steam capacity via four dual-fuel water tube boilers. The distribution system includes 36-inch chilled water mains, 18-inch steam mains and condensate return.
Our design and analysis included the evaluation of using direct buried versus tunnel installation of distribution piping, as well as coordination with existing site utilities. As part of the decommissioning of the old plant, we designed the removal of portions of existing utility tunnels that were deteriorated beyond repair.
We designed new valve vaults to allow for service and access to the underground valves that would have been previously located in a walkable steam tunnel. To properly account for the expansion and contraction inherent in a steam distribution system, our team developed a full stress analysis model to determine the expected thermal expansion. The results of this model were used to specify the expansion compensation provisions, which consisted of buried anchors and expansion joints.
Our team provided full commissioning services beginning in the early design phase through the warranty phase. The Cx scope included: developing the commissioning plan and specifications; conducting reviews of the design documents; leading commissioning effort throughout construction, site visits functional testing and integrated systems testing; logging and tracking issues; reviewing contractor startup reports and turnover documentation; and developing a final Cx report and systems manual. Systems commissioned were HVAC, electrical, plumbing, building automation and TAB (testing, adjusting and balancing), and building enclosure.
