Design and Construction of a Semi-Automated and Automated Oxygen Transfer Efficiency Instrument for Optimizing Aeration in Activated Sludge Plants

The lack of user friendliness of present Offgas Transfer Efficiency (OTE) measurement equipment has been a great impediment to many of the operating activated sludge plants in establishing an aeration-basin diffuser maintenance program. Commercially available OTE instruments are large, cumbersome, fragile, and staff resource intensive. The basic principle of the existing OTE equipment is to bring an offgas stream released by the basin to an oxygen meter under controlled conditions throughout the measuring event to capture raw data. Several of the mechanisms used to sustain controlled conditions can be replaced with modern and smaller components to fabricate a more user-friendly system. Thus, recent technological advances have presented the opportunity for a smaller and more manageable new design that retains the same reliability as its predecessor. The resulting modified semi-automated OTE equipment and the subsequent testing will be presented in this paper. Plans for design and construction of a fully automated OTE instrument will be discussed.