A Pilot Scale Study of Low Dissolved Oxygen Nutrient Removal Supplemented with Ammonia-Based Aeration Controls

dissolved oxygen;nutrient removal;wastewater

Chambers, Evan D.Noguera, Daniel ;

University of Wisconsin

关键词: dissolved oxygen;    nutrient removal;    wastewater;   

Others  :  https://minds.wisconsin.edu/bitstream/handle/1793/78594/MS_Thesis_Chambers_Evan.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: University of Wisconsin

【 摘 要 】

In order to refine a previously acclimated pilot to low dissolved oxygen (DO) conditions fornutrient removal, ammonia-based aeration control was introduced in an effort to successfullyremove ammonia throughout an entire year. Historical operations of the low DO pilot, operated ata fixed DO setpoint of 0.5 mg/L, allowed for efficient nutrient removal until water temperaturesdecreased with drastic seasonal changes present in at the Nine Springs Wastewater Treatment Plantin Madison, WI. By implementing ammonia-based aeration controls in the secondary treatmentprocess, triggered by operator adjustable ammonia setpoints, the pilot was allowed to operatebetween high and low DO modes to call for additional oxygen when ammonia loads increased,and call for less oxygen, as an energy saver, when an ammonia setpoint is achieved. In addition,data from the ammonia probe was compiled and summarized which provides an enhancedunderstanding of the process that was previously not possible to obtain. This shows the daily, andeven hourly, variability that the pilot experiences in response to influent loadings and seasonaltransitions. In comparing the first iteration of ammonia-based controls with the previous years offixed DO operation, recommendations and enhancements are provided to optimize the process forfuture work. The study provided insight into the various physical configurations to be consideredwith the control strategy and also evaluates the side effects, both positive and negative, that comewith implementing ammonia-based controls on a low DO pilot reactor.