Plant Upgrades Optimized by Efficient Whole Plant Evaluations

The Oak Lodge Wastewater Treatment Plant (WWTP) uses a conventional activated sludge process and requires significant rehabilitation and upgrades to address its aging infrastructure and growing service population. Along with variations of activated sludge processes, various process options were developed aimed at maximum utilization of existing facilities and innovative treatment of wet weather flows. These included chemically enhanced primary treatment, Cannibal solids reduction process, split-treatment with membrane bioreactors, and integrated fixed-film activated sludge alternatives. A whole-plant evaluation approach that coupled process simulations with conceptual cost estimates allowed for efficient consideration of the plant upgrade options. Operational carbon footprints were estimated to assess the environmental impacts of various alternatives. Evaluation results indicate that Cannibal solids reduction technique integrated with the activated sludge process requires lowest construction and operational costs, without generating a carbon footprint substantially larger than other alternatives.