AMMONIA REMOVAL ALTERNATIVES EVALUATION: TREATING WASTEWATER TO BELOW DRINKING WATER STANDARDS

摘要

The South District Water Reclamation Plant (SDWRP) will be Miami-Dade County's first large scale alternative water supply project to be implemented in accordance with requirements of the County's Water Use Permit (WUP). This facility will use what is currently known as best available technology to treat effluent from the South District Wastewater Treatment Plant (SDWWTP) to drinking water standards, including the following main processes: membrane filtration (MF), reverse osmosis (RO), and ultraviolet advanced oxidation (UV-A). Early in project development, the need for nutrient control in the plant's effluent to very low levels became critical criteria for process design. Nutrient limits were established based on discussions with regulatory agencies, specifically ammonia and total phosphorus concentrations of 0.5 mg/L as nitrogen and Below Reporting Limit (BRL), respectively. Even though the processes proposed above are capable of removing/rejecting a large percentage of these two nutrients from the effluent stream, the project team identified additional processes to supplement the main SDWRP processes to obtain the effluent quality listed above. This paper documents the nutrient removal alternatives evaluated for ammonia control at the SDWRP, starting with the preliminary set of proposed alternatives, the initial screening process, the final alternatives development and evaluation, and selection of the final alternative.