Associated presents at Water Environment Association of Ontario Annual Conference

Associated Engineering is pleased to announce the following individuals will be presenting in various streams of the technical program next week in Toronto at 52nd WEAO Technical Symposium. We invite all delegates to hear from our speakers on April 17 and 18th!

April 17, 2023

4:15 PM - 4:45 PM | Maple West
Modelling the Impacts of Grey Water Reuse Implementation on Wastewater Treatment Plants | Ryan Thoren  

Grey water treatment systems collect, store and treat grey water to specified standards for reuse. Depending on the level of treatment, this enables the use of treated grey water for applications such as above-ground irrigation, laundry, and toilet flushing. In addition to reduced demands on drinking water distribution and wastewater collection systems, implementation of grey water reuse has the potential to impact WWTP operations. To assess the potential impacts on WWTPs, a model was developed to predict changes to WWTP influent flows, concentrations, and mass loadings as a result of grey water reuse implementation. Two scenarios were modeled to investigate different rates of grey water reuse uptake in newly constructed homes for a medium-sized municipality (population of 500,000 people). Results were determined up to the year 2051 using population and housing development projections. The impacts of reduced flows on sewage collection systems were also assessed at a high level.

4:15 PM - 4:45 PM | Willow East

Rooftop Solar Systems at Wastewater Collection and Treatment Facilities | Don Bai

Rooftop Solar Systems at Wastewater Collection and Treatment Facilities | Don Bai
Drivers and Key Considerations to designing and constructing rooftop solar systems at Wastewater treatment and collection system facilities. Followed up with a case study examination of a success deployment.

4:45 PM - 5:15 PM | Willow Centre
Feasibility of Advanced Digestion Options to Reduce Biosolids Volume | José Bicudo

This paper discusses the feasibility of biosolids management options based on variations and enhancement of anaerobic digestion, which might help address capacity concerns at a regional composting facility. Different options were analyzed for biosolids volume reduction, energy generation and use, life-cycle cost, including sensitivity to select input parameters. A structured decision-making process, using a simplified triple bottom line (TBL) approach, is also included to provide a comparative evaluation of the options and inform the City on a number of important corporate considerations.

April 18, 2023

10:30 AM - 11:00 AM | Maple West
Wiped Out? - Screens for Small Wastewater Treatment Plants | Amir Esmaeili    

Wastewater treatment plants (WWTPs) servicing small communities with rated average daily flows of less than 500 m3/d do not typically have screening units (fine screens). In the past, this was done as a cost-saving measure for these small communities and was deemed to not significantly impact the downstream treatment processes. Operational and maintenance problems associated with nuisance inorganic solids, such as flushable wipes, have become more prevalent in many sewage pumping stations and WWTPs. These problems include plugging of pumps and piping, material settling in quiescent areas of tanks and reduced quality of the biosolids. Implementing screen units in small WWTPs would mitigate the operational issues associated with flushable wipes clogging pumps and process piping. The objectives of this paper are to describe design criteria and considerations for implementing screen units in small WWTPs; present suitable screening technologies for small WWTPs; and discuss challenges with implementing screen units in existing facilities.

1:30 pm – 2:00 pm | Willow West
Investigating Plant-wide and Process-Specific Odour Emissions | Nico Carunungan 

In response to odour complaints made by residents living near the Kitchener and Hespeler Wastewater Treatment Plants in 2021 and 2022 respectively, we studied regional weather data, reviewed plant operating conditions, and measured odour emissions at both facilities to determine any causal relationships between treatment activities and the complaints received. It was determined that neither plant was generating odours that could have caused the nearby residential complaints over the durations of the study periods. A key point of interest to note is that we investigated the Kitchener WWTP on a plant-wide scale, while we put specific emphasis on the aerobic digestion process at the Hespeler WWTP as it had been recently upgraded to treat thickened waste activated sludge. Through both studies, we demonstrate that baseline profiling of odour emissions is essential to determining any causal relationships between wastewater treatment processes and sources of odours at treatment facilities.

2:30 PM – 3:00 PM  | Willow West
Managing Odours from Biosolids Storage and Processing - A Case Study from the Galt WWTP | Michael Blain

Biosolids processing facilities, particularly those including dewatered cake storage and truck loading bays, can produce a complex mixture of odours beyond the typical compounds such as H2S that are often the focus of odour treatment at wastewater treatment plants (WWTPs). At the Galt WWTP, there are two parallel carbon adsorption systems for building and process air treatment for the Biosolids Facility. This paper describes multiple rounds of odour sampling over the course of 8 years, and the presence of compounds including organic sulpur, ammonia, and volatile organic compounds that contribute to the odour mixture and require treatment. The paper also reviews technology options to treat this mixture including activated carbon, biofilter, and chemical scrubber, as well as constructability and life cycle cost considerations for this retrofit application.