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What’s in a name? That which we call a rose by any other name would smell as sweet.

William Shakespeare

The best and most innovative ideas often evolve from combining two or more disparate technologies together to create a whole new solution. This is a story of exactly this sort of inventive approach to a classic municipal problem.

Anyone who lives near a waste water treatment plant or even has driven past one, knows very well how bad they can smell. The odors permeating from these plants can be rather putrid and are certainly off-putting. Generally speaking, foul odors at treatment plants originate from the anaerobic decomposition of organic compounds. Yuck. The joyous smells of rotting waste. Due to its low solubility in wastewater, it is released into the atmosphere, producing an offensive odor. Amines and mercaptans are two other odor-causing offenders at treatment plants.

Controlling odors is one of the most important – and yet most challenging – aspects of waste water treatment. Foul odors are often a source of complaints, igniting objections from plant workers and neighbors alike.

Although many odors are contained within the proximity of the plant, some odors naturally drift to surrounding areas. They waft into public parks and subdivisions that have been built around the plant over the years. Understandably, communities are not tolerant of these nuisance odors, causing people to complain. Depending on the severity of the odors, citizens will often call the plant to pressure management to find a solution, or they will reach out to politicians and the media. Odor complaints that become borderline political and/or receive negative media attention risk damaging the plant’s – and the brand’s – reputation.

Uncontrolled odors can also impact the overall job satisfaction of plant workers. Treatment plants value their employees and should make efforts to improve their working environment by better controlling odors.

Not all odors are created equal; they vary in intensity. Some are faint, while others are much more pungent. This is why, when people complain about odors, plant workers will typically ask what time they detected the odor, what it smelled like, and how intense it was.

Weather conditions can intensify odors. Temperature inversions, wind velocity, and wind direction contribute to how far odor emissions drift. Odors are typically worse at higher temperatures. Factor in increased summer activity, and it is not a surprise that plant management usually receives more odor complaints during the warmer months of the year. Plant maintenance – either planned or unplanned – and/or upgrades to treatment processes are other aspects that can affect the severity of odors.

The first step in solving any odor problem is identifying the source. Odors could be coming from raw wastewater exposed to air at the influent pump station and primary clarifier stage. Unfortunately, the odors could also be coming from nearly any other step along the treatment train. Since the culprit could be a number of different things, or some combination thereof, it’s best to pinpoint the source of odors with the help of a professional consultant.

There are many odor control technologies in the marketplace and no single, universally ideal solution exists. Some plants use deodorizing misting systems to target volatilized odor compounds in the air. Others choose to add chemicals directly to the water that react with odor-causing compounds. Fine-tuning the treatment process itself is another odor control tactic, albeit a more complex one.

Often the simplest approach to odor control is quite literally covering the problem. Many wastewater treatment plants choose to seal the source of odors – whether that is a tank, basin, or lagoon – with an industrial-grade cover, thereby preventing the diffusion of odor vapors.

“Capture and treat” technology is an even more powerful odor control solution. This involves capturing odors by containing them with a cover, and then withdrawing and treating the collected foul air. Once the air is conveyed in a ductwork system, it can be treated by a variety of technologies such as a biofilter, wet scrubber, carbon filter, proprietary media, etc.

We now have some interesting new tools available to detect odors better. These tools include artificial intelligence, internet of things, sensors, edge computing, and more. Add into this mix the need to position these IoT sensors with drones at exactly the right spot and then dynamically map it all in real-time for visualization. By taking all of these technologies and mixing them into a pot, some fascinating innovation can result.

Now, some very brilliant inventors resulting from a collaboration between the Institute for Bioengineering of Catalonia (IBEC) and the company DAM, a new way is being opened to detect and treat these odors.

According to the researchers, “the results obtained in the SNIFFDRONE project (Odor monitoring by drones for environmental purposes) are very positive and represent a significant advance in the field of odor management in the waste water treatment plants. The new system will help to take appropriate control actions and therefore improve the management of the plant compared to current practices”.

This is how the technicians from the DAM R & D department express themselves, when assessing the work carried out in this European research that ended on October 31st. Specifically, a drone has been developed capable of predicting “the odor concentration from the readings of chemical sensors and providing measurements that help to locate the sources of origin”, indicate from DAM.

The study, carried out together with the IBEC, starts from the reality that current odor evaluation methodologies use measurements infrequent olfactometric measurements that do not allow a precise characterization, so an effective monitoring of the plant cannot be carried out.

“The system provides odor concentration maps that help to take appropriate control actions and therefore improve plant management compared to current practices,” explain the researchers from DAM.

The drone is configured with an electronic nose made up of 21 chemical sensors, plus temperature, humidity and pressure sensors, in a miniature sensor chamber. It also contains a sampling system, GPS positioning, and connects to a base station for signal processing and data analysis in real time.

“The system has been calibrated and validated in real operating conditions through several measurement campaigns at the Molina de Segura WWTP (Murcia). The results obtained allow us to obtain a prototype capable of predicting the intensity of the odor of ambient air samples in real time and simultaneously collecting samples for analysis in the laboratory after the flight, which allows us to calibrate and validate the operation of the system ” , stand out from the Valencian water purification company.

“The developed drone allows, thanks to a combination of chemical sensors and artificial intelligence, to quickly assess the intensity of the odor emitted by a waste management plant in large areas that are sometimes difficult to access. This information is relevant for the plant operators with the ultimate goal of minimizing the impact on neighboring communities “, declares Santi Marco, Head of the Group of Signal and Information Processing for Sensing Systems at IBEC and Professor at the University of Barcelona.

For all these reasons, the DAM Innovation department technicians consider that the results of SNIFFDRONE represent a significant advance in the field of odor management in waste water treatment plants, since until now “the odor detection robots had been tested with Single-odor chemical sources in relatively simple controlled scenarios and in most cases using ground-based robots”, they conclude.

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Burgués J, Esclapez MD, Doñate S, Pastor L, Marco S. Aerial Mapping of Odorous Gases in a Wastewater Treatment Plant Using a Small Drone. Remote Sensing. 2021;13(9):1757. doi:10.3390/rs13091757

Howe, B. (2021). Odors at Wastewater Treatment Plants. WaterWorld. Endeavour Business Media. Retrieved on June 9, 2021 from,

Unknown. (2021). Drones Help Waste Treatment Plants Get to Grips With Bad Smells. Retrieved on June 9, 2021 from,

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About the Author:

Michael Martin is the Vice President of Technology with Metercor Inc., a Smart Meter, IoT, and Smart City systems integrator based in Canada. He has more than 35 years of experience in systems design for applications that use broadband networks, optical fibre, wireless, and digital communications technologies. He is a business and technology consultant. He was senior executive consultant for 15 years with IBM, where he has worked in the GBS Global Center of Competency for Energy and Utilities and the GTS Global Center of Excellence for Energy and Utilities. He is a founding partner and President of MICAN Communications and before that was President of Comlink Systems Limited and Ensat Broadcast Services, Inc., both divisions of Cygnal Technologies Corporation (CYN: TSX). Martin currently serves on the Board of Directors for TeraGo Inc (TGO: TSX) and previously served on the Board of Directors for Avante Logixx Inc. (XX: TSX.V).  He has served as a Member, SCC ISO-IEC JTC 1/SC-41 – Internet of Things and related technologies, ISO – International Organization for Standardization, and as a member of the NIST SP 500-325 Fog Computing Conceptual Model, National Institute of Standards and Technology. He served on the Board of Governors of the University of Ontario Institute of Technology (UOIT) [now OntarioTech University] and on the Board of Advisers of five different Colleges in Ontario.  For 16 years he served on the Board of the Society of Motion Picture and Television Engineers (SMPTE), Toronto Section.  He holds three master’s degrees, in business (MBA), communication (MA), and education (MEd). As well, he has three undergraduate diplomas and five certifications in business, computer programming, internetworking, project management, media, photography, and communication technology. He has earned 20 badges in next generation MOOC continuous education in IoT, Cloud, AI and Cognitive systems, Blockchain, Agile, Big Data, Design Thinking, Security, and more.