Demonstration of High Quality Drinking Water Production Using Multi-Stage Ozone-Biological Filtration (BAF): A Comparison of DPR with Existing IPR Practice
Project: 15-11
Type: Scientific Investigation
Scope of Work
Program: Tailored Collaboration
Budget: $922,718 (Cash: $100,000, In-kind cash and service: 822,718)
Background
National trends indicate increasing interest in providing sustainable water supply solutions that leverage advances in the science and engineering of water treatment for potable reuse practices. Currently, the operating direct potable reuse (DPR) projects in Texas rely on a modification of the full advanced treatment (FAT) model that has been the standard for planned IPR in California. The FAT train leverages advanced treatment technologies that are linked together and include microfiltration/ultrafiltration (MF/UF), reverse osmosis (RO), ultraviolet (UV) light disinfection, and advanced oxidation (AOP) to form a multi-barrier treatment process. While this model has been proven in terms of producing source water quality that is suitable for both IPR and DPR, the process has a very high capital cost and is energy intensive, particularly for inland facilities where RO concentrate disposal is complicated and expensive. When total dissolved solids reduction is not necessary from the source water, there are alternative treatment processes such as ozone biologically active filtration (BAF), following advanced wastewater treatment that can achieve high quality for drinking water supplies.
Goals and Objectives
The goals and objectives of this project are to
- Develop a process control strategy for BAF that can be applied to DPR
- Integrate the monitoring framework developed for Water Research Foundation Project 4508/WRRF Project 13-14 and provide an in-depth validation of these tools. This will provide data to allow rigorous analysis of the practicality and functionality of these monitoring parameters.
- Integrate the project with several concurrent research projects, allowing development of a robust dataset for comparison with both current drinking water quality produced by IPR and with data that has been previously collected at potable reuse pilots and full-scale FAT treatment train projects.
- Finally, there are lake-turnover events that impact the source water quality in Lake Lanier; this project will investigate the feasibility of utilizing DPR to overcome process challenges that Gwinnett County Department of Water Resources and many other municipalities face. This unique aspect of the project will provide additional data which may demonstrate that DPR using two-stage BAF could be a viable means of providing additional process resiliency to upset conditions.
Research Approach
- Task 1 – Literature and Pilot Test Plan: A focused literature review will be conducted to summarize the state of knowledge with respect to DPR treatment options and installation, water quality, and quality benchmark. This will be followed by a detailed plan for DPR pilot testing.
- Task 2 – Pilot Operations and Optimization: This will include up to 12 months of DPR pilot testing with four sequential phases: baseline operating conditions, testing of blending ratios, optimization, and robustness and contingency testing.
- Task 3 – Process Integration: The assessment of process integration potential will be developed by identifying the blending ratios and optimization strategies that demonstrate the most promise for full-scale implementation.
- Task 4 – Reporting: The results from the pilot testing and cost estimates will be synthesized into a practical report including detailed implementation plans.