Wastewater Training, 2 of 3

The video script begins with a welcome message and an introduction to the second round of New Epic's wastewater training. Drew Youngs is moderating the session with Jim as the expert trainer. Drew outlines housekeeping items, reminding participants to mute their microphones to reduce background noise and use the chat function for questions. The training will be recorded for later access, and the focus of this session is on biological treatment processes, including microbiology and the role of single-celled bacteria in wastewater treatment.

The paragraph delves into the biological treatment process, emphasizing the importance of carbon, nitrogen, and phosphorus for the bacteria. It discusses the transformation of organic matter into bacteria and the necessity of oxygen for their survival. The script also touches on the different types of organisms found in wastewater and the significance of maintaining a balance of nutrients for effective treatment. Additionally, it highlights the role of dissolved oxygen and the use of a microscope for process control.

This section describes various types of microorganisms involved in the wastewater treatment process, including their shapes (rod, spiral, and spherical) and their roles in the ecosystem. It explains the life cycle and reproduction of these organisms, which are predominantly single-celled bacteria. The paragraph also discusses the significance of different types of bacteria, such as heterotrophs and autotrophs, in the treatment process and the importance of maintaining a proper balance of nutrients for their metabolism.

The script explains the importance of microscopic examination in the wastewater treatment process. It provides insights into the different types of organisms observed under a microscope, such as flagellates, ciliates, and filamentous bacteria, and how their presence can indicate the health of the treatment process. It also discusses the significance of sludge age and the need to remove old sludge to maintain the efficiency of the system.

This paragraph discusses the growth phases of microorganisms in the treatment process, including the lag phase, exponential growth, declining growth, and endogenous phase. It explains the concept of self-cannibalization among bacteria when food resources are scarce. The script also touches on different types of trickling filters, their functions, and the importance of recirculation in maintaining the health of the biological process.

The script addresses operational issues in wastewater treatment, such as maintaining the health of trickling filters, dealing with excess leaves in the fall, and managing high flows during rainstorms. It suggests solutions like increasing recirculation rates, physically clearing blocked areas, and the strategic use of recirculation to prevent filter fly issues. The paragraph also highlights the importance of keeping the system wet during low flow periods.

This section introduces rotating biological contactors (RBCs), which are used in smaller facilities and package plants. It explains the structure and operation of RBCs, which consist of a series of plastic discs that rotate through a tank of wastewater, providing a surface for bacteria to grow. The paragraph also discusses the advantages of RBCs, such as their large surface area for biomass support and their simple operation.

The script provides an overview of the activated sludge process, which offers more control over the biological treatment compared to trickling filters and RBCs. It discusses the importance of nitrogen and phosphorus supplementation in certain wastewater types and the need for aeration in the activated sludge system. The paragraph also explains the concept of mixed liquor suspended solids (MLSS) and mixed liquor volatile suspended solids (MLVSS) as key indicators of the process's health.

This paragraph describes various types of activated sludge processes, including conventional, complete mix, contact stabilization, step feed, extended aeration, oxidation ditches, and membrane bioreactors. It discusses the specific conditions, advantages, and applications of each process, such as their oxygen demand, retention times, and suitability for different types of communities and treatment needs.

The script explores the combination of fixed film and suspended growth processes to maximize treatment efficiency within a given tank volume. It discusses the challenges of wet weather and infiltration, leading to the need for retention systems. The paragraph also mentions the use of moving bed bioreactors (MBBRs) as a solution for limited space and the need for better containment of the biomedia used in the process.

This section discusses different methods of aeration in wastewater treatment, including mechanical surface aerators, diffused aeration, and positive displacement blowers. It emphasizes the importance of even oxygen distribution and the challenges of maintaining aeration in large tanks. The script also touches on energy efficiency measures, such as control loops and the use of high purity oxygen in certain facilities.

The paragraph addresses safety concerns related to high oxygen content areas and the complexities of operating high oxygen systems. It then explains various airflow measurement techniques, such as the use of an orifice plate and thermal mass air flow meters, which help regulate airflow and maintain optimal conditions within the treatment tanks.

The script details the secondary clarification process, where water from the reactor enters a clarifier tank and solids are allowed to settle. It discusses the importance of maintaining a sludge blanket, the design of clarifiers, and the challenges of managing light sludge materials. The paragraph also covers methods for sludge removal, the impact of mixed liquor concentration on settling, and the use of devices like sludge judges for measuring sludge blanket levels.

This section provides an overview of lagoon treatment systems, which are common in rural areas and require minimal technology. It explains the different types of lagoons, such as aerobic, anaerobic, and facultative, and their reliance on sunlight and biological processes for treatment. The script also discusses the maintenance challenges associated with lagoons, including the removal of accumulated solids and the control of vegetation and wildlife.

The final paragraph addresses queries from the audience about the functioning of secondary clarifiers and the energy demands of treatment plants. It also mentions the use of renewable energy sources like solar arrays and methane gas from anaerobic digestion to supplement energy requirements. The session concludes with a reminder about the availability of the training units online and an invitation for participants to reach out with further questions.