- Seal Air Upgrade Study
We provided engineering services for a seal air upgrades study, including preliminary engineering and a Class 3 cost estimate to define and size booster fans for a dedicated seal air system for the coal mills serving Unit 15 at Rollin M. Schahfer Generating Station.
NIPSCO provides seal air to its six coal mills at RMSGS from the tempered air system. The seal air system is required to be 25 inches wc higher than the air inside the mills. Since the tempered air system is used to convey pulverized coal dust to the boiler, this means the tempered air dampers to each mill are left 5 percent to 10 percent open to achieve the required pressure drop. However, this condition does not allow for significant variability in air flow to the boiler, limiting the ability of RMSGS to adjust capacity to match demand.
Our team performed preliminary engineering to evaluate the impacts of providing dedicated booster fans to provide seal air to the mills. This system would still take seal air from the tempered air system, limiting the impact on the existing installation. To appropriately estimate total installed cost for the project, we developed a detailed duct routing to fully evaluate system parameters and cost. A Class 3 estimate was furnished, incorporating project and owner costs needed for internal budget approval.
This project required thorough assessment of the current installation and proposed design of the system upgrades. Frequent collaboration with NIPSCO increased the accuracy of the estimate, which helped to minimize the recommended contingency.
- Engineering and design
- System analysis and modeling
- Fan sizing
- Limited installation footprint and restrictive area for duct routing