Biochemical Oxygen Demand (BOD/CBOD) Automated Analyzer

The City of St. Petersburg is seeking quotes from qualified vendors to provide instrumentation and technology for the Water Resources Department to operate an automated Biochemical Oxygen Demand (BOD/CBOD) analytical system for use in environmental laboratory operations. The system will support continuous compliance testing required for Florida Department of Environmental Protection (DEP) permitting of Water Reclamation Facilities (WRFs), as well as Industrial Pretreatment Program (IPP) and SWAMP requirements. The Water Resources Department is currently running laboratory operations and analyzing the recorded data in-house, manually.

Biochemical Oxygen Demand (BOD) analysis is a multi-step analytical procedure involving the preparation of individual samples, aliquoting into analysis containers for appropriate dilutions, addition of reagents and dilution water, and measurement of initial Dissolved Oxygen (DO). Following preparation and initial DO determination, samples are incubated for a period of five days under controlled conditions. Upon completion of the incubation period, final DO measurements are obtained, and the oxygen demand is calculated. The initial setup phase typically requires several hours and involves the processing and measurement of approximately 30 to 60 samples per analytical batch.

Currently, the analyst manually performs all sample preparation activities, including pipetting sample aliquots and preparing the required dilutions. Reagents are subsequently added by hand, and each bottle is analyzed for initial Dissolved Oxygen (DO) prior to placement in the incubator. As one batch is placed into incubation, a corresponding batch that has completed the five-day incubation period is removed for final DO measurement. The analyst then calculates the oxygen demand for each aliquot and records the results in the Laboratory Information Management System (LIMS). This analysis is conducted seven days per week, 365 days per year, and requires approximately six hours per batch for setup and completion of readings.

The proposed system would automatically record all dilutions, reagent additions, and analytical measurements, perform all required calculations, and transmit results directly to the Laboratory Information Management System (LIMS). Implementation of an automated analysis platform would eliminate repetitive and labor-intensive sample handling steps, reduce manual intervention, and decrease total setup and reading time to two hours or less. In addition, automation would enhance data integrity by minimizing the potential for errors associated with manual calculations and data entry.