AC25 Water Reuse & Advanced Water Treatment Track Bundle

CWEA Member: $150.00
Non-Member: $195.00

3.0 contact hours towards CWEA's AWT certifications.
This series includes the following 50 minute sessions. 

Session 1: Inevitable Role of Secondary Treatment in Direct Potable Reuse Facilities
California DPR Regulations require ozone and biological active carbon (BAC) filtration ahead of full advanced treatment consisting of reverse osmosis (RO) and advanced oxidation process (AOP). The main purpose of ozone and BAC is to address low molecular weight organic compounds some of which such as acetone, formaldehyde cannot be effectively removed by the full advanced treatment. The other purpose of ozone-BAC is to provide an additional barrier for chemical peak “averaging”. While Ozone-BAC can provide an effective barrier for low molecular weight compounds that are poorly removed by full advanced treatment, the capabilities of ozone-BAC is limited to relatively small chemical peaking based on North City chemical spike studies. However, one critical area has not come to closer attention of State Water Board. That is the secondary treatment. In this presentation, we will explain inevitable role of secondary treatment in a DPR train. First, an activated sludge based secondary treatment can provide excellent removal for slowly biodegradable organic compounds such as acetone, formaldehyde and all other low molecular alcohols and ketones that are poorly removed by full advanced treatment. Second, a secondary treatment can provide nitrogen control which is critical to meet nitrite and nitrate nitrogen primary MCLs of 1 and 10 mg/L, respectively. These limits may not be reliably met in RO-based full advanced treatment if no nitrogen control is provided in the upstream wastewater treatment plant (e.g., Hyperion WRP). Third, a good nitrogen control is essential to minimize secondary effluent nitrite concentration which creates very high ozone demand during ozonation. Last but not least, a well-designed and operated secondary treatment can provide a high-quality effluent with reduced suspended solids, phosphate and metals which can create operational challenges at downstream advanced water purification facility (AWPF).

In summary, how a robust secondary treatment along with performance requirements make DPR possible and case study examples will be presented to demonstrate how secondary process performance affects & defines AWPF design, performance & operation in a DPR train. It will provide an unmatched value for public and regulatory agencies to explore how secondary treatment that makes DPR projects more robust and resilient.

Learning Objectives:
To understand capabilities and limitations of ozone and BAC for chemical control in DPR projects
To understand role and superior benefits of activated sludge based secondary treatment in DPR
To understand how we can configure secondary treatment to make DPR projects more robust and resilient

Session 2: Secondary Effluent Quality, Potable Reuse, and Nitrogen Removal: Considerations for Multi-Benefit Projects
Water reclamation facilities are facing a variety of new challenges, including the move toward potable reuse and new regulations to limit nitrogen discharges. This presentation explores the interactions between secondary effluent quality, potable reuse, and nitrogen removal.

Successful potable reuse requires high-quality, consistent secondary effluent. The first part of this presentation will discuss typical advanced treatment trains for potable reuse and identify the critical design parameters impacted by the secondary treatment processes. Key differences between secondary treatment types will be quantified. The evaluation documents higher concentrations and higher variability in non-nitrifying facilities for several key parameters for potable reuse design, including total organic carbon (TOC), ammonia, and nitrite. For non-nitrifying plants, average TOCs ranged from 14 to 27 mg-N/L; nitrifying plants averaged 10 mg-N/L or less. Some non-nitrifying plants routinely reported nitrite concentrations above 2 mg-N/L, and even the fully nitrified facilities occasionally reported nitrite concentrations above 1 mg-N/L and ammonia concentrations above 2 mg-N/L. Plants considering potable reuse should begin monitoring TOC and nitrite to provide data for advanced treatment design. Optimization or upgrades to secondary treatment may be necessary, depending on the advanced treatment goals and requirements. The presentation will help planners and designers understand the suitability and challenges of their secondary effluent for potable reuse.

Plants with new nitrogen limits are considering multi-benefit solutions incorporating recycled water and potable reuse to reduce nitrogen discharges. The second part of this presentation will discuss the impact of potable reuse on nitrogen discharges. A variety of upgrade scenarios for a conventional BOD-removal only plant upgrading to potable reuse will be considered, and the impact on nitrogen removal will be quantified. Scenarios considered include different secondary treatment types (conventional BOD-removal like trickling filter solids contact and nitrification/denitrification in activated sludge), different management of reverse osmosis concentrate (discharge of concentrate, return of concentrate to the plant influent, and separate treatment of concentrate), and a range of potable reuse flows. Although each plant situation is unique, the results will help planners and designers understand the feasibility of using potable reuse to reduce nitrogen discharges and the key factors that impact nitrogen discharges.

Learning Objectives:
Upon completion, participants will be able to list three secondary effluent quality parameters key to potable reuse design.
Upon completion, participants will be able to describe the suitability and challenges of their secondary effluent for potable reuse.
Upon completion, participants will be able to understand the key potable reuse design decisions that impact nitrogen discharges.

Session 3: Assessment of Virus Removal and Infectivity During Municipal Wastewater Treatment: Implications for Safe Reuse
Pathogen control and monitoring in water reuse applications is critical to public health protection and gaining public trust. As more utilities and water agencies consider implementing water reuse programs, obtaining credit for log reduction values (LRV) achieved through secondary and tertiary wastewater treatment processes will be an important consideration. While many utilities exploring reuse options are currently focused on membrane processes to achieve additional virus log removal credits, questions remain regarding LRV achieved through various conventional treatment trains. In addition, while molecular assays exist for the detection of viruses, the majority of these methods provide no information on culturability or infectivity thus making extrapolation of end-user exposure risk and identification of suitable applications challenging.

The objective of this study was to assess the removal of human infective viruses throughout the stages of wastewater treatment in a full-scale, tertiary municipal wastewater treatment plant in Canada. The plant resells 20% of its secondary effluent to an industrial partner after additional treatment by membrane filtration and chlorination. The remaining 80% of the secondary effluent undergoes UV disinfection prior to release into the environment. The partnership between the plant and the industrial partner produces 15 million liters of high-quality water for processing each day, which are used in the refinery cooling tower, boiler and hydrogen plant. Virus concentrations and infectivity were analysed using real-time quantitative PCR (qPCR) and integrated cell culture (ICC) to identify infective human viruses. Seven viruses including Norovirus (NoV), Rotavirus (RV), Sapovirus (SaV), Astrovirus (AsV), Adenovirus (AdV), Enterovirus (EV) and JC virus (JCV) were detected in 16 primary effluent samples in which infective viruses were present. Different treatment steps showed various efficiencies in infective virus removal, with membrane filtration exhibiting the highest at 4.6–7.0 log reductions.

The overall treatment virus LRV ranged from 1.1 (RV) to 2.8 (EV) for UV-treated final effluent and from 4.6 (EV) to 7.0 (AdV) when membrane filtration and chlorination were applied. The LRV for the six viruses (except for EV) by membrane filtration were significantly greater than that obtained by UV. EV had the highest inactivation by UV but the lowest by membrane filtration.

Learning Objectives:
After the presentation, participants will be able to articulate the benefits and limitations of different viral testing methods and the potential value that coliphage testing might add.
After the presentation, participants will be able to compare the removal of viruses after various treatment steps.
After the presentation, participants will have more data to highlight the value and potential virus log removal credits that can be achieved by ultrafiltration (6–7 LRV).

Registrants who view the live webinar to see the slides and hear the audio and then enter the correct attention check code (directions below) will receive 3.0 contact hours towards CWEA's certification:AWT

To receive your contact hours for viewing the recording, you will need to view each video in the series. Upon completion of the last video in the series, the system will automatically unlock the attention check code for you view. The two (2) different attention check codes that will be displayed, and you will need to enter these codes as 1st attention check code – 2nd attention check code (XXXX-XXXX) in the Attention Check Code component under the "Contents" tab.  

Please note, all user activity of CWEA certification holders on the Online Wastewater Education Network is subject to the CWEA Code of Ethics standards for professional conduct and ethics. Certification holders should receive credit for a training only once within the same contact hour period. Any attempt to undermine the certification process may be subject to ethics procedures and possible sanctions. It is not possible to receive contact hours for both attending the live webinar and viewing the recording.  

Once you have entered the correct attendance check codes, you will be able to create and download an electronic certificate of completion under the "Contents" tab.