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Shawn Scott, RVA President, CEO
Shawn Scott, President and CEO of RVA

Shawn Scott, RVA President, CEO
Shawn Scott, President and CEO of RVA

ES&E Magazine spoke with Shawn Scott, President and CEO of R.V. Anderson Associates (RVA), to talk about the company’s new look, and opportunities for consulting engineering in Canada.
By Peter Davey, Managing Editor, ES&E Magazine

RVA recently announced a new logo and identity. What made the company decide on this new look?

With the retirement of Ken Morrison, our past-president, and a number of senior directors in the firm, RVA has gone through a generational change in the company. To refocus the company, we embarked on a strategic planning exercise with the intent of refreshing our vision and establishing new goals for the firm.

As part of our new vision, it seemed fitting to rebrand the firm, and that we tie the new direction of the company with a new look.

RVA logoIt’s worth mentioning that our new logo maintains the tie to the iconic “double-A” which was developed by our founder Roderick Anderson and was synonymous with us being referred to as “Anderson’s Associates”. It was important to come up with a logo that maintained the history of the company, and one that our clients could readily identify with.

How does growth fit into your strategic plan?

One of our strategic goals targeted growing the company. We have increased our staffing by almost 15% over the last year and a half, and we’re continuing to focus on organic growth and ultimately branching out and expanding into new geographical areas.

Tying into the human capital needs of the firm moving forward, we asked: “What are the things that we need to do to become a great place to work?” We have introduced changes such as health and wellness programs, a corporate gym membership and improved vacation benefits.

Consulting engineering companies are often announcing mergers and acquisitions. What is your outlook on this and does it fit into RVA’s plans?

It’s interesting that we have seen acquisitions come full circle to some degree. The larger firms continue to buy up the smaller firms, but now we have started to see the spin-off firms start up, as the senior partners of acquired firms leave to branch out and start smaller companies.

In terms of RVA, our shareholders were unanimous in maintaining our employee-owned structure. We are certainly exploring strategic acquisition opportunities to find a firm that shares the same culture and values that we do, and shares our growth strategy.

Water, wastewater and transportation are your primary business areas. What challenges and opportunities do you see in the future for these sectors in Canada?

The challenges are many. We are starting to see the effects of growth, demographic changes and climate change on our infrastructure. The recent flooding in Quebec and New Brunswick is one example of the impact climate change is having on our systems. With an increase in the frequency and intensity of storm events, our infrastructure is being put under more and more pressure.

From my perspective, there are many opportunities with infrastructure renewal. We’re just starting to see the pressure on the systems, and the need for municipalities to keep up with their current and developing strategies. RVA is well positioned to aid our clients with these changes.

Are there any areas of growth that you see when it comes to infrastructure projects?

Certainty, asset management and facility management have become a larger part of our business as our clients continue to focus on prioritizing their capital projects and needs. I think the pressure on our infrastructure is going to lead to a focus on alternative delivery models, such as design-build and  Private-Public-Partnerships, to be able to deliver projects in a timely fashion. We are certainly starting to be more involved in the alternative delivery market.

How do the coming years look for consulting engineering in Canada?

I would say that I’m bullish on the outlook. We see a lot of opportunities in the infrastructure marketplace and certainly with our current clients. From our perspective, there are many opportunities in 2017 and we’re looking at that continuing well into 2018 and 2019.

This article appears in ES&E Magazine’s June 2017 issue.

Figure-11---Finished-Tank---Final
By Mark Bruder

In October 2014, a 90-year-old reservoir at the Peterborough water treatment plant experienced a leak event. A detailed summary of the condition assessment and short-term structural repair efforts was published by Environmental Science & Engineering Magazine in the July/August 2015 issue.

This article is an overview of the long-term rehabilitation follow-up work to help further extend the service life of the reservoir.

Scope, schedule, budget

At the end of 2015, Peterborough Utilities Commission (PUC) retained R.V. Anderson Associates Limited (RVA) to provide consulting engineering services for the long-term rehabilitation of its 90-year-old reservoir. This allowed for continuity from the initial short-term repair efforts through to commissioning of the fully rehabilitated reservoir. The scope of RVA’s services included design, tendering, contract administration, and site inspection during construction.

The general project scope included temporarily decommissioning the 50 m2 by 5 m deep buried concrete reservoir, jacketing several concrete columns inside the reservoir, providing for structural and process removals and modifications, pressure washing and rehabilitating concrete surfaces, and pouring a new concrete floor topping.

Consulting engineering services commenced in January 2016 and construction started in June. This quick turnaround was essential to ensure that PUC had sufficient water storage capacity. Work was completed on schedule and on budget.

The construction budget was $2,900,000. This is roughly a third of the cost of an alternative solution to demolish the existing tank and build a new one in its place. The fully rehabilitated reservoir is likely to remain operable for another full life cycle. Therefore, the rehabilitation solution provided high value for the cost.

 

Condition prior to project kick-off

Peterborough’s 90-year-old reservoir had serviced the City well beyond its expected life span. Prior to the long-term rehabilitation project, the reservoir had undergone short-term repair efforts. This included performing a potable water dive, sealing over 360 m of floor cracks with polyurethane, and concrete pressure grouting over 11 m3 of voids that were present underneath the floor slab of chlorine contact tank #1 (CCT#1) and clear well #3 (CW#3). At that time, only CCT#1 and CW#3 were accessible because of the reservoir bypass operation. After project kick-off, when the reservoir was fully decommissioned, it was possible to perform a visual condition assessment inside the chambers.

In the influent chamber, across all concrete surfaces, heavy deterioration had led to fully exposed aggregates. This left the walls vulnerable to further, and faster, deterioration of the concrete and steel reinforcement. The highest chlorine dosage in the reservoir occurs in the influent chamber, which corresponds to the type and extent of the deterioration.

In the effluent chamber, across all concrete surfaces, a thin layer of alum residue was present. This is consistent with other portions of the reservoir prior to the short-term repair efforts. It appeared that the alum residue had protected the concrete surfaces from further deterioration. However, the residue was undesirable for operations.

Of the 70 concrete columns throughout CCT#1 and CW#3, 10 were heavily deteriorated across their full height. In some instances, steel reinforcement was exposed and showed signs of corrosion. Curiously, most of these 10 columns were located sequentially along the same reservoir grid line. It was suspected that they had been poured with a different concrete mix design that was unintentionally susceptible to chlorine attack.

The tender documents included a provisional allowance for 10 additional column jackets in case previously unknown heavy deterioration was uncovered after pressure washing.

In general, some minor cracks were identified in the slabs and walls, and all concrete surfaces having previously been in contact with chlorinated water had mild surficial deterioration of about 5 mm. Neither the cracks nor the deterioration were structural in nature. Therefore, it was important to rehabilitate the 10 heavily deteriorated columns before addressing the serviceability issues.

Concrete column jackets

The heavily deteriorated columns required more than simple surficial repairs. The chosen structural design included full-height, 175 mm thick, steel-reinforced concrete “jackets” that encapsulated the existing columns. The jackets were keyed into the existing floor below but terminated at the upper column capital thickening.

The jackets required a high-performance concrete mix due to constructability challenges and the inherent chemical environment in the reservoir. The mix type was Agilia self-consolidating concrete by Lafarge. This allowed for pumping through the bottom and mid-level of the formwork without having to vibrate the concrete. The concrete exposure class was C-XL to help resist future chemical attack. The compressive strength was 50 MPa at 56 days, which is the minimum strength available for the chosen mix and exposure class.

Continuous wet curing was specified for seven days. Upon formwork removal, the concrete surface was exceptionally smooth and exhibited no shrinkage cracks.

Removals and modifications

A variety of structural and process work was completed to facilitate rehabilitation efforts and upgrade operations.

A flow meter chamber was constructed adjacent to the reservoir. Replacement of chemical lines occurred within CCT#1, CW#3, and the small influent and effluent chambers. The existing reservoir was retrofitted to connect to the new nearby reservoir with a 1200 mm diameter concrete pressure pipe, complete with an isolation sluice gate. New baffle curtains were installed in a different layout to improve the baffle factor and reduce stagnation zones. Finally, all existing metal gates and valves that were leaking were refurbished or replaced.

A small, unused chamber connected to the existing reservoir was abandoned by filling it with cellular grout. This was to permanently seal it from the rest of the reservoir, thus preventing water from leaking in, becoming stagnant, and affecting the overall water quality.

The suspended aeration steps were removed, as they were no longer necessary for operations. Portions of the roof slab were removed to either create new access hatches or to seal existing openings. Some deteriorated areas of the floor slab were removed, as shallow patching would have been insufficient to prevent leakage through the floor. Ultimately, removals and modifications amounted to a low percentage of the project cost.

Cementitious parging and waterproofing

It was necessary to re-establish concrete surfaces that had deteriorated from contact with the chlorinated water. For heavy deterioration greater than 40 mm, pourable concrete and formwork was used. For shallow deterioration between 10 and 40 mm, the chosen built-up patching material was SikaTop 123 PLUS by Sika. Regardless of the depth of deterioration, all concrete surfaces were coated with a thin, cementitious, chemical-resistant parging (surface coating) layer. All rehabilitation products were NSF 61 certified for potable water use.

The surface was prepared via 7,000 psi pressure washing. The 90-year-old concrete was easily able to withstand this pressure at close range, even with a millimetre-thin nozzle applied to heavily deteriorated areas. Sand-blasting was not an option, as concrete surfaces must be clean of debris for rehabilitation products to properly adhere. The minimum specified surface roughness was CSP-3 as per the International Concrete Repair Institute. The maximum allowable depth of concrete removal was 10 mm. During tendering, these and other performance criteria were helpful to the bidders in establishing a base scope of work.

The project specified that a 2 m³ mock-up be developed with the concrete rehabilitation products. This was to increase PUC’s confidence in the performance of the approved applicators and the chosen products. A strict contractual condition was that no products could be applied to the remainder of the reservoir until RVA and the product manufacturer had approved the quality of the mock-up. Ultimately, the column and wall mock-ups were completed successfully.

For the columns, the finishing parging layer was SikaTop 123 PLUS, complete with a steel trowel application and smooth steel float finish. Waterproofing was not required for the columns, as the parging layer was sufficient to protect the base concrete from further deterioration. A smooth finish is desirable for a water reservoir, as less surface area equals less potential bacteria accumulation.

For the walls, the underlying parging layer was CEM-KOTE CW PLUS extended with masonry sand. Although this product has its own crystalline waterproofing properties, a finishing waterproofing layer of CEM-KOTE FLEX ST was also used. Both of these products are by W. R. Meadows. To help reduce leaks out of the reservoir, both products were applied to the positive pressure (inside) face of all perimeter walls.

The parging application sequence was as follows: 1) thin brushed slurry primer coat of CW PLUS; 2) thick trowelled coat of CW PLUS; and 3) sprayed then brushed double coating of FLEX ST.

A notable benefit of the wall parging material was the ability to embed between built-up layers a reinforcing polymeric fabric that could bridge small cracks. This was used to further mitigate leaks out of the reservoir.

For this rehabilitation work, the cost to pressure wash, parge, and waterproof the walls was roughly $275 to $325 per square metre. A rough production rate was 1 to 3 square metres per hour.

Fibre reinforced concrete floor topping

Through the previous short-term repair efforts, polyurethane was injected into hundreds of linear metres of floor cracks. However, polyurethane is not intended to provide a long-term waterproofing solution. Typically, polyurethane is ineffective beyond five years of service. Therefore, a cost-benefit analysis was undertaken to determine the best waterproofing solution for long-term performance of the existing floor slab.

Two options were considered: 1) pour a topping slab on the existing floor: and 2) demolish the existing floor and pour a new one in place. The first option was superior in cost and schedule, and PUC accepted the minor reduction in storage volume.

A standard concrete mix was used with a C-1 exposure class and 35 MPa compressive strength after 56 days. Preventing leakage through the existing floor slab was a major priority for PUC. Therefore, the topping thickness was a robust 200 mm, as thinner unreinforced toppings can delaminate and crack. The topping was dosed with 35 kg/m³ of macro steel fibre reinforcement by Bekaert. This dosage, for the specific type of selected steel fibre, is equivalent to minimum conventional steel reinforcement, and was designed to provide superior crack control.

Alternative reinforcement types were considered, including poly-synthetic fibres, welded wire mesh, and conventional steel reinforcement. The latter two were rejected because of cost, schedule, and constructability, as there were significant access limitations into CCT#1 and CW#3. PUC rejected the synthetic fibres, as they lacked NSF 61 certification and could be exposed at the topping surface.

Weeks ahead of the first topping pour, a trial pour was completed off-site. The intention was to validate that the concrete mix design, fibre dosage, and placing/finishing techniques would meet the high-performance standards outlined in the specifications. The test was successful and yielded valuable insight into how small adjustments to the mix and execution can lead to significant improvements in performance.

The fibres were dosed at the concrete batching plant rather than on site. This allowed for the concrete supplier to maintain tight quality control. On site, the concrete was loaded from the mixing truck into a concrete pump. The concrete was then transported into the below-ground reservoir via a conventional flexible “elephant trunk” hose. Ahead of concrete placement, the existing floor slab was pressure washed and then prepared with a wet binding mix of cement and water.

At times, the fibres formed “icebergs” within the mixing truck, pump, and hose. This was corrected in two ways: 1) by adding superplasticizer at the concrete batching plant; and 2) by vigorously spinning the concrete mixer immediately ahead of pumping.

To help reduce shrinkage cracks, the topping was poured in a checkerboard pattern. Construction joints, complete with PVC waterstops, were used in between sequential panel pours. A continuous, hydrophilic bentonite waterstop was used along the perimeter of the wall/slab interface. Steel reinforcing dowels were used to anchor the topping to the existing walls and overtop cracks in the floor slab that had previously been injected with polyurethane.

The topping was finished first with a wooden bull float and then a magnesium steel trowel to prevent sticking. A continuous wet cure was specified for 10 days. Because of the nature of this particular below-grade reservoir, optimal curing conditions were present, including a consistent temperature, high moisture level, and protection from the wind. This yielded a superior, smooth concrete finish with virtually no shrinkage cracks. Any cracks that were found in the topping were short and less than a few millimetres in depth.

Lessons learned in reservoir project

Overall, this project was a success for all stakeholders. Due to the comprehensive long-term rehabilitation work that was completed, coupled with PUC’s effective asset management approach, this reservoir should remain in serviceable condition for another life cycle.

There are many benefits to maintaining existing infrastructure and extracting maximum value from available assets.

If a deteriorated, leaking, 90-year-old reservoir can be rehabilitated to working conditions, then perhaps other facilities can recuperate significant value from their assets.

Mark Bruder, P.Eng., is with R.V. Anderson Associates Limited. This article appears in ES&E Magazine’s June 2017 issue.

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Cartwright Springs Brewery installs MBBR system.
Installing Premier Tech Aqua's Ecoprocess™ Moving Bed Biofilm Reactor (MBBR) System.

In recent years, the number of small craft breweries has greatly increased and so has the wastewater generated by brewers. As for all other food and beverage sectors, effluents from microbreweries are regulated and required to meet wastewater discharge regulations.

In terms of treatment efficiency, footprint and cost, very few wastewater treatment technologies prove to be up to the challenge, which in part explains why most microbreweries discharge raw effluent to a municipal wastewater treatment plant, instead of having a dedicated on-site treatment system.

Challenges

In April 2015, the Cartwright Springs Brewery, together with its representative Fieldstone Engineering, was looking for a solution for treating wastewater generated by its newly constructed microbrewery, located in Pakenham, Ontario, west of Ottawa. The brewery production capacity was limited to 2,000 L/week, which suggested that wastewater generation would be approximately 10,000 L/week. The wastewater to be treated was a combination of all the streams: the yeast dump and mash dump (i.e., high strength, low pH), wash water (i.e., low strength, high pH), and domestic wastewater from the pub (950 L/day). The combined flow after seven days of equalization was estimated to be 2,380 L/day.

MBBR Solution

After an extensive sampling campaign performed by the engineering firm on similar installations, the EcoprocessTM Moving Bed Biofilm Reactor (MBBR) from Premier Tech Aqua was selected. The objective-based design was for the combined streams to be pretreated to primary domestic effluent (i.e., BOD: 100 mg/L to 180 mg/L) and then discharged by gravity to a leaching bed. Treatment included a balancing tank, septic tank, MBBR units (two stages), final clarifier with sludge management, and leaching bed. To benefit from lower electricity rates, the treatment unit integrated a smart control strategy that made operating mainly at night possible, whenever the incoming wastewater flow was lower than the one set for the design.

Results

The system was put into operation in July 2015 and has performed extremely well since then. BOD concentration at the inlet varies between 1,500 mg/L and 2,500 mg/L, and laboratory results show a steady removal rate of 99%.

The moving bed biofilm reactor is a compact and high-performance treatment system available as a ready-to-use solution or in a cast-on-site concrete basin. It applies to a host of commercial, institutional and municipal projects, including those to increase the performance of aerated lagoons.

This article appears in ES&E Magazine’s June 2017 issue.

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Peter Laughton
Peter Laughton addressing an annual luncheon of the Select Society of Sanitary Sludge Shovelers.
By Peter J. Laughton

In June 1997, I delivered a convocation address to engineering graduates of all disciplines at Ryerson Polytechnic University (now Ryerson University), titled: Towards Engineering Excellence in the 21st Century.

Given that some 20 years have passed, I took this anniversary as an opportunity to review and reflect on the relevance of the convocation address in today’s setting. I concluded that I would deliver a similar address today to young graduating engineers, with text reference to the current millennium. However, in doing so, the following would be included:

  • Expand, emphasize and stress today’s environmental issues before us.
  • Expand, emphasize and stress the need for sustainability.
  • Stress the need to hone analytical skills to meet the challenges of complex problem solving.
  • Address the issue of climate change and the necessity for graduates to participate in this area. They need to bring about a concrete resolution, with foreseeable tangible results. Thus, they will leave a constructive legacy for our time and for future millennia.
  • Emphasize the need to actively support and become involved in associations and societies related to one’s engineering discipline.

For those of you who are in the early throes of your engineering careers and for those who are mentoring young engineers, I would like to share the following excerpts from my 1997 address, which I believe are still sound and relevant today:

“Some qualities may never be part of future course work material and may not be the subject of direct examination grade as you move on in life. I am speaking about dedication, integrity and hard work. These are the basic ingredients for your professional reputation, and hence, your status in the engineering community.

“As you enter the business world, the immediate challenge will be to apply your acquired skills. However, it must be recognized that the next millennium will belong to those engineers who are willing to embrace and accept rapid change, who know where they are going, who are extremely competent and knowledgeable in their area of expertise, and, as well, to those who strive for a high standard of excellence.

“As a leader and a strategic thinker, you must be a team player in multi-disciplined situations and you must be able to demonstrate a high level of understanding of social, economic and environmental issues.

“Your success as an engineer will also be tied directly to your communication skills. This skillset must be honed to the same degree as your technical and business skills.

“The aforementioned attributes will not be an option but an absolute necessity – they are inextricably linked.

“In an increasingly complex and demanding world, you must be flexible and prepared to rethink and readjust your goals. We are living in an era of dramatic changes that are taking place in all aspects of society. The sweeping changes in the marketplace are global and they are affecting the everyday lives of us all. The economies of the world are undergoing major transformations.

“Canada and Canadians must compete in the global economy to prosper. As we rapidly undergo this shift to globalization, it will be necessary for engineers, in the coming century, to further expand the societal dimensions of their work and to resolve challenges through holistic approaches.

“During a recent trip, I was browsing through a copy of a prominent airline inflight magazine and came across the following statement which I think addresses the importance of remaining on this cutting edge: ‘Technology is reshaping our lives, and those who miss even one step are in danger of never catching up.’

“A commitment to keeping pace with advances in technology will be a prerequisite requirement for success in the next century. It has been said that the best preparation for good work tomorrow is to do good work today.

“In order to see us through this global transformation and to maintain our country as one of the best places in the world to live, it will be your responsibility, in the next century, not to just identify problems and solutions but to bring about concrete results. You must follow up on ‘work of conviction’ to bring about tangible results and in doing so leave a legacy of constructive change.

“You and other members of your generation will inherit and have entrusted to you a key role in the stewardship of our society. I would urge you to demonstrate leadership and initiative now and establish realistic and achievable goals that will lead to a sustainable society, thus ensuring a sustainable future for all Canadians. There will be continued concern for the environment on the local, national and global level, which will extend well into the next century.

“In closing, I would like to stress the need to share a common direction and sense of community with those around us. An author once wrote and if I may paraphrase: When you see geese heading south for the winter flying along in a ‘V’ formation, it has been learned that as each bird flaps its wings, it creates uplift for the bird immediately following. By flying in a ‘V’ formation, the whole flock adds greater flying range than if each bird flew on its own.

“The translation explained was that people who share a common direction and sense of community can get where they are going quicker and easier because they are travelling on the thrust of one another.”

Peter J. Laughton, M.Eng., B.A., Ph.D. (Honoris Causa), P.Eng., BCEE, FCSCE, is a retired consulting engineer, a past president of the Water Environment Association of Ontario and long time member of ES&E Magazine’s Editorial Advisory Board. This article appears in ES&E Magazine’s June 2017 issue.

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World Water Day poster
WWD 2017 poster (click to enlarge)
By Connie Zehr

Have you heard of the “Sludge to Energy “plant in Xiangyang, China, the restoration of the Balkans “Lake of Apples”, or water pollution controls in Bangladesh’s textile industry? If you’d like to broaden your awareness of global issues, take just a little time to browse through one of the United Nations World Water Day websites, hosted by the UN Water Group. World Water Day is an annual awareness project, officially celebrated on March 22, but worthy of our attention all year round.

The United Nations has generated global Sustainable Development Goals, also called Seventeen Goals to Transform our World, first widely publicized in 2015.

Goal 6 (Clean Water and Sanitation for All) is an ambitious target to provide everyone on Earth with access to safe water by 2030. This is a challenge considering that, at present, about one-third of the world’s population cannot claim this basic right. Contaminated water affects the health of millions, who may contract polio, typhoid, dysentery and cholera, or spend hours a day managing their water supply.

In addition to the perennial need for sustainable drinking water treatment and sanitation, the UN reminds us that water scarcity looms on the horizon for many global citizens as the climate changes.

As professionals in environmental engineering and ecology, we are well aware of the scope and extent of these important challenges but don’t always get to celebrate progress toward improvements. Every year UN-Water publishes resources and success stories from around the world on specific subtopics related to Goal 6. Recent clean water and sanitation themes have included Water and Energy (2014), Water and Sustainable Development (2015), and Water and Jobs (2016).

The 2017 theme is Wastewater and the website has useful background documents written for the general public. Several projects are profiled, including the St. Petersburg, Florida, dual distribution system for reclaimed water, the on-site wastewater treatment at Schiphol Airport in Amsterdam (functionally equivalent to a city of 45,000 people) or the use of desalination technology to reclaim mining wastewater in South Africa. Other links are for specialists and lead to technical sites (Antimicrobial Resistance), research agencies (Isotope Hydrology), or projects like the training of water chemists in Bihar, India.

TV Ontario’s “Down in the Sewer” flushables video and the position paper on energy and water sponsored by AWWA and WEF are both included in this year’s theme. Others involve tropical issues like irrigation water concerns, Brazil’s wastewater challenges, or the dry lake in Colombia that was recovered with recycled water.

Here are a few suggestions to inspire your own learning or enliven events with clients, coworkers, tour groups or presentation audiences, during World Water Day or year-round:

  • Jazz up a bulletin board with a downloadable poster. There are sharp infographics and colourful images in a variety of languages.
  • Use the Instagram and Facebook links for a quick electronic visit to a new location. www.instagram.com/un_water/
  • Across the globe, how much wastewater flows back to nature untreated? Spend 50 seconds with colourful video on the topic. https://youtu.be/UrJhsH0Sz_o
  • Try the new wastewater calculation app or add an animation to a presentation. www.worldwaterday.org/the-wastewater-calculator/
  • How many of the glamourous celebrities (other than Shania Twain) for safe water do you recognize? www.worldwaterday.org/5414-2/
  • Notice or celebrate World Toilet Day (Nov 19).

Connie Zehr is with the School of Engineering and Applied Science at Centennial College in Toronto. This article appears in ES&E Magazine’s June 2017 issue.

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Nereda aerobic granular sludge plant, Epe, Netherlands
The Nereda aerobic granular sludge plant in Epe, Netherlands.

The AquaNereda® aerobic granular sludge system (AGS) from Aqua-Aerobic Systems, Inc. is an innovative biological wastewater treatment technology that provides advanced nutrient removal, significantly smaller footprint, and up to 50% less energy, using the unique features of aerobic granular biomass.

One of the defining characteristics of the AquaNereda aerobic granule is rapid settling which in turn allows for a significant increase in biomass concentration. Granules are comprised entirely of true biomass and therefore do not require carriers. The layered microbial community that forms the granule is able to achieve enhanced biological nutrient removal, including simultaneous nitrification/denitrification and phosphorus reduction.

Enhanced settling properties

In an AGS system, bacteria are present as large dense granules, as opposed to fluffy suspended flocs. The density of these aerobic granules increases settling up to 15 times greater compared to conventional activated sludge systems. By overcoming settling limitations seen in conventional activated sludge systems, the mixed liquor can be increased significantly, which allows for a greater treatment capacity. Sludge volume index decreases to values of 30 ml/g – 50 ml/g, which allows the bioreactor to operate at mixed liquor suspended solids concentrations of 8,000 mg/l or higher.

Reduced footprint

Footprint is reduced up to 75% due to the full nutrient removal process taking place in a single reactor. Supplemental tanks such as primary clarifiers, selector basins, separate anoxic and aerobic compartments, and secondary clarifiers are not required. Also, the biomass operates at a higher concentration, allowing for increased treatment capacity within a single tank.

Energy savings

Reduction of air requirements in the bioreactor tank allows for substantial energy savings. The substrate and oxygen utilization rates in the aerobic granular system lower the specific energy and airflow. Based on the operation in a single reactor, the equipment required for the aerobic granular sludge process is significantly reduced, when compared to conventional activated sludge systems. Also, sludge recycling pumps are not needed. The combination of reduced aeration and mechanical components results in an energy savings of up to 50%.

Low life cycle cost

The reduction in mechanical equipment necessary to achieve enhanced biological nutrient removal requirements lowers construction, operating and maintenance costs. In addition, chemical consumption is reduced due to the high bio-P uptake in the aerobic granular biomass. These savings in operation and maintenance, as well as the lower construction costs, result in attractive whole life cycle costs.

How it works

Aerobic granular sludge combines the technical advantages of biofilm systems, including compactness and high metabolic rates, with those of activated sludge. This includes the ability to achieve full biological nutrient removal in one mixed biomass population, without the need for biofilm carriers. Aerobic, anoxic, and anaerobic biological processes take place simultaneously in the granular biomass.

Liquid solid separation in a flocculant sludge system occurs by using sedimentation in clarifiers. Due to the fact that flocs have low density, the settling time is much greater than a denser granular biomass, which will achieve full settling in five minutes.

As a result, a conventional plant is designed at 2,500 mg/l – 5,000 mg/l of mixed liquor, compared to an aerobic granular sludge plant at 8,000 mg/l or higher. Aerobic granular sludge displays a greater concentration of specialized micro organisms that are layered. Different types of microorganisms will grow in the granule that can result in a typical particle size of 1.2 mm – 1.5 mm in diameter. Nitrifiers reside on the outer layer of the granule and denitrifying bacteria are present in the deeper layers.

During aeration, oxygen can penetrate about 100 – 200 microns into the granule before it is depleted. This results in the inner part of the granule, nearest the core, being an anaerobic zone and the outside layers being aerobic and anoxic zones. Both the oxygen and substrate are transported into the granule via diffusion.

Phosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs) are present throughout the biomass and have the ability to form extracellular polymeric substance (EPS) that is the building block for granular formation.

Extracellular polymeric substance

Due to its robust structure, the granule has the ability to withstand upset conditions. The extracellular polymeric substance serves as the backbone of the granule and enables the system to withstand fluctuations in chemicals, loading, salinity, pH, toxic shocks, etc. This chemical backbone makes it difficult to interfere with the enhanced settling and stable process characteristics. Process stability, along with settling properties, result in a reliable and robust granular system that is easy to operate.

Granule formation

In an AquaNereda aerobic granular sludge system, selection mechanisms are applied to create dense granules from flocculant biomass. As an alternate, a plant can be seeded with granules from another site. Conventional biomass flocs are selectively wasted by increasing sedimentation stress. The stress continues to increase, thus enlarging the size and density of the flocs, which causes them to settle faster and evolve into granules. Only the bacteria that can adapt due to the selection mechanisms are able to survive in a granule form.

Aqua Nereda cycleCycle structure

Within a single tank, the AGS system creates proper conditions to reliably maintain a stable granule, without the need of a carrier. Due to the layered microbial community within the granule structure, simultaneous processes take place in the granular biomass, including enhanced biological phosphorus reduction, and simultaneous nitrification/denitrification.

Based on the unique characteristics of granular biomass, the AquaNereda system uses an optimized batch cycle structure. There are three main cycles of the process to meet advanced wastewater treatment objectives. Phase durations will be based upon the specific waste characteristics, the flow and the effluent objectives:

Fill/draw. The first phase of the cycle structure is fill/draw, where the influent flow first enters the reactor. The anoxic and anaerobic conditions provide biomass conditioning and phosphorus release. At the same time, treated water is displaced towards the effluent at the top of the AquaNereda AGS reactor.

React. Influent flow is terminated in the second phase of the cycle structure known as the react (aeration) phase. In this phase the biomass is subjected to aerobic and anoxic conditions. The granules perform simultaneous nitrification/denitrification. Concurrently, nitrate is transported by diffusion between outer aerated and inner anoxic layers of the granule, eliminating the need for pumping large recycle flows in the plant. Within the bioreactor, luxury uptake of phosphorus is promoted. The automated control of the process allows energy savings and process optimization.

Settling. Upon completion of the aeration phase, the system proceeds into a settle phase. Here, the influent flow still does not enter the reactor. The granular biomass is separated from the treated water during a very short settling period. Excess sludge is wasted in order to maintain the desired amount of biomass. Finally, the system is ready for a new cycle and influent enters the reactor while the treated water is discharged.

Process and cycle structures are optimized through the use of automated controls. While wastewater flows, loadings and temperatures fluctuate, the process parameters will be adjusted for efficient performance.

Applications

Typical applications for an aerobic granular sludge system include: retrofit of existing tanks, increasing treatment capacity, upgrade of existing treatment systems to meet more stringent effluent requirement, or greenfield sites, and enhanced biological nutrient removal.

Nereda aerobic granular sludge plant in Epe, Netherlands

Epe is the location of the first Nereda Aerobic Granular Sludge full-scale municipal system and has been in operation since 2009. It treats an average design flow of 2.1 MGD and a peak hour flow of 9.5 MGD using a three reactor design. Granulation occurred over the winter months, at temperatures below 10°C . The Nereda reactors are followed by tertiary filters, achieving 0.34 gm/l total phosphorus. Overall, the conversion to Nereda AGS reduced energy consumption by 40%. Currently, over 30 full-scale Nereda plants are operational or under construction.

Aqua-Aerobic Systems is currently building a full-scale system at the Rock River Water Reclamation District in Rockford, Illinois, which will demonstrate the system in North America.

Exclusive representation of the AquaNereda system in Canada is through ACG – Envirocan (Eastern Canada) and Waste n’ Watertech (Western Canada).

This article appears in ES&E Magazine’s June 2017 issue.

Strathcona County SCADA software system
All graphics were designed based on ISA High Performance Graphics Standards.
By Trihedral Engineering and MPE Engineering

In 2016, Strathcona County, Alberta, decided to replace its aging SCADA software system that was no longer supported by the vendor. Inconsistent tag naming made it frustrating to develop and the lack of continuity in the displays made it confusing to operate. Access to historical data was time-consuming and remote access was limited. Most critically, the system had no backup, should its single server fail.

The County is comprised of several thriving communities with over 98,000 residents within the Edmonton Metropolitan Area. Their utilities department is responsible for the operations and maintenance of the water and wastewater systems located within Sherwood Park and in various rural hamlets throughout the County.

The County selected MPE Engineering Ltd. to design and deploy a new SCADA application which complies with industry standards such as High Performance Graphics and the ISA 18.2 Alarms.

SCADA architecture

VTScada now monitors 53 remote sites, consisting of the water pump house, water pressure reducing valves, lift stations and wastewater lagoons. VTScada uses an integrated driver library to directly communicate with the utility’s monitoring and control hardware, which includes GE 90-30 PLCs, GE-Rx3i PLCs, Siemens S7-1200 PLCs, and SCADAPack remote terminal units (RTUs).

The MPE team configured three networked SCADA servers to provide redundancy and flexible workstation access. Since VTScada’s architecture is integrated, each of these servers contains a complete copy of all historical and configuration data synchronized up to the second.

The new servers improve system access both in the office and in the field. There is now a dedicated engineering workstation with a four-monitor setup and two operator workstations, one quad monitor and one dual monitor. A replicated workstation in a demilitarized zone (DMZ) allows remote third-party access to VTScada historical data from a non-production machine.

A fourth operator workstation was configured on an internet facing network and allows operators to access VTScada or other SCADA systems over the internet. VTScada’s integrated Thin Clients allow operators to remotely access their process via mobile devices such as tablets and smart phones.

Consistent tag design

Tags were standardized using ISA 5.1 naming conventions. The old system used Modbus addresses for all tag names and had no descriptions in the tags. The client provided an extensive list of tag names and descriptors. MPE Engineering managed the creation of tags using VTScada Context Tags.

“These parent tags represent devices with multiple child tags representing device attributes such as statuses, values and alarms,” says Zane Spencer, Project Manager and Controls Programmer with MPE.

High performance graphics

All graphics were designed based on ISA High Performance Graphics Standards. This design methodology uses simple greyscale graphics to represent a system operating normally. Colour begins to emerge as values approach tolerances or alarms are tripped. This approach allows operators to instantly see emerging problems. VTScada’s extensive library of greyscale images and symbols can change colour and appearance based on tag values.

“High performance graphics were client driven, which was nice because we did not have to sell this to the operators; the client took care of that,” says Spencer. “Operators did not love the greyscale graphics at first, but once the benefits and added contextual information was explained to them, they warmed to the idea and now, after a few months, truly enjoy the benefits associated with the new graphics.”

ISA 18.2 alarming

The ISA 18.2 Alarm Management Standard helps utilities to develop a consistent approach to alarm creation and acknowledgement. It also helps to reduce nuisance alarms which can obscure real issues. VTScada’s integrated Alarms Manager uses colour, symbols and sound to allow operators to easily scan the alarm list and see the status and priority of each alarm. Built-in reports help to identify “Bad Actor” alarms, trace “alarm floods”, and audit alarm priority distribution per ISA’s recommendations.

During scheduled hardware maintenance, staff can temporarily “shelve” associated alarms to avoid distractions.

Reporting

MPE used the native report generator to create the following reports which are all grouped by type and station:

  • Totalized flows from flow totalizers.
  • Daily runtime of all monitored hour meters.
  • Minimum, maximum and average chlorine levels.
  • Water pressure.
  • Motor amperages.
  • Reservoir levels.
  • Totalized water consumption flows for the Regional Water Customers Group.

Reports automatically run each day at midnight for the previous day. The system can automatically email reports to the appropriate people or send them to a printer. They can also encompass the daily reports into monthly and/or yearly reports. Staff can create custom reports based on tags, time frame, date, or other criteria.

The VTScada reporting system works directly with standard Excel reporting templates, which only required slight modification, eliminating the need for third-party middleware software.

Remote “Thin Client” access

Now, multiple operators, managers and engineers have secure remote access, using mobile phones and tablets. Using the VTScada Anywhere Client, paired with the unlimited Thin Client licenses, there are no concerns about users fighting for control of the system. The Anywhere Client provides a consistent operator experience using any HTML5 compliant browser.

Distributed local historians

The County was also concerned about the potential loss of data should the connection to remote sites be lost. In response, MPE configured the application to allow for use of VTScada as local human machine interfaces (HMIs) at all remote stations. If the station is cut off from the central application, the local HMI continues to provide local monitoring and control, while collecting alarm and historical data. When communications to the site are restored, all local alarm and historical data is backfilled into the central SCADA system.

This was completed for one of the major pump houses during this project. To implement this solution, MPE supplied and installed a local panel mount PC, replacing an existing HMI at the local station.

“It is running the same VTScada application as the centralized servers but using tag and alarm area filtering to reduce the license cost and present only relevant information to local operators,” says Spencer. “Using VTScada as a HMI replacement, and structuring the tag database appropriately, we have effectively implemented historical store-and-forward, allowing the County to eliminate data loss when communication links to the station are disrupted.”

An added benefit is the synchronization with the central system; all graphics, user accounts, alarm history, and alarm configurations are synchronized in real-time. The SCADA application is pre-structured to allow for this configuration at all remote sites. The County would like to implement VTScada as a local HMI for all stations in the future.

Installation

The replacement system was designed and tested in parallel with the existing system to eliminate downtime. The project was completed under budget with no disruption to operations or significant system failures during the switchover. As with anything, there were some glitches to work through during the testing and commissioning phases. However, due to the template-based tag database, large scale changes could be rapidly deployed and tested with minimal system impact.

Conclusions

“Do your research first, attend training if possible for multiple platforms, and select the one that you would like to work with for the next 20 years,” says Spencer. “Talk to sales personnel, but also talk to the management teams and tech support teams to get a sense of the support that you will receive after the initial purchase. Also, be specific when preparing request for proposal documents and select qualified consultants who have proven experience with the preferred software solution.”

This article appears in ES&E Magazine’s June 2017 issue.

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Fate of biogas chart. Click to enlarge.
The fate of biogas.
By Patrick Coleman

The biogas “universe” transcends municipal departments and has expanded beyond just the generation of heat and electricity. In the past, the answer to the question “how to best use biogas?” was either to produce hot water or to produce electricity. Today, the answer is much more complex because the demand for, and production of, biogas has increased.

Biogas is produced by the anaerobic bacterial degradation of organic material, such as sewage sludges, source-separated organics, food wastes, farm materials or industrial byproducts (e.g., glycerine). Biogas is produced at wastewater treatment plants, farms, solid waste facilities, landfills and industrial sites.

The carbon dioxide produced when burning natural gas is a greenhouse gas (GHG), while that when burning biogas is not. Biogas carbon is produced as part of the natural cycle, which includes the digestion of biologically based materials. This said, because methane is a greenhouse gas, a biogas end user will produce a GHG emission if unutilized methane is emitted to atmosphere.

The potential to produce biogas has not been fully realized in Canada. It is estimated that Ontario alone could produce 752 Mm3/year of renewable natural gas (i.e., upgraded biogas) from anaerobic digestion. This is less than 3% of Ontario’s year 2015 (fossil fuel) natural gas consumption. With gasification, this number increases to 17% of Ontario’s year 2015 natural gas consumption. Action 6.1 of Ontario’s Five Year Climate Action Plan is to lower the carbon content of natural gas in Ontario by sourcing gas from renewable sources. At the right price, biogas producers would be able to supply sufficient biogas to support a 2% mandatory renewable requirement.

The cost to produce and utilize biogas depends partly on the cost to prepare material for digestion, the cost to clean the biogas (i.e., condition), the cost to manage undigested material, and the cost to utilize the biogas.

The economic return of a biogas project is based on the savings accrued by using biogas rather than another form of energy, or based on the market value of the biogas product itself. Biogas can be used to produce thermal, electrical and motive energy. There may be enough savings realized by altering how a facility uses biogas to pay for the capital investment to make the change. Grants from governments are designed to bias this evaluation towards achieving a policy outcome (e.g., reduction in grid peak demand or reduction of GHG emissions).

However, a business case is most attractive when the sale of the biogas product generates a revenue stream that pays for the project. The viability of most biogas projects depends on savings obtained, incentives awarded, and profits realized.

Raw biogas is “wet”, 60% – 70% methane and “dirty”. Conditioned biogas is “clean” and “dry”. The end use of the biogas determines the degree of conditioning required. For example, a gas turbine requires cleaner biogas than a boiler. Contaminants in raw biogas that impact most end users are siloxanes, hydrogen sulfide, ammonia, oxygen, nitrogen and moisture.

Clean (conditioned) biogas can be used to direct drive blowers or pumps, exported as a fuel, or sold as a raw material (e.g., to produce bioplastics). On one recent project, a community housing entity offered to purchase all the conditioned biogas produced by a proposed wastewater treatment plant to reduce its GHG emissions.

A more common situation is to use biogas to produce heat. This is conveyed either directly as steam or hot water (e.g., steam injection into a reactor) or indirectly through heat exchangers (e.g., hot water circuit). The biogas can also be compressed and conveyed to provide heat directly (e.g., incinerator burners) or indirectly (e.g., heating of thermal oil. The value of this biogas is equal to the value of natural gas not purchased and greenhouse gas emissions not emitted.

Biogas is also used as fuel to generate electricity (and heat). This electricity can be exported to the grid or can be used “behind the meter” at the facility where it is generated. The common end users are internal combustion engines, combustion gas turbines, steam turbines and microturbines. The value of the electricity produced depends on incentives, electricity pricing, and the cost to supply the energy to an end user.

The cost to export electricity, or to export any form of energy, depends on the distance to the tie in point and the requirements to match the exported power to the power characteristics at the connection point. For electricity, the characteristic may be voltage; for renewable natural gas, pressure; and for hot water or steam, temperature.

The willingness to provide an incentive depends partly on the grid electricity GHG emission factor. The Canadian National Inventory Report estimates that the 2014 electricity emission factor for Manitoba is 3.9 g CO2e/kWh, Ontario is 50 g CO2e/kWh, and Saskatchewan is 820 g CO2e/kWh. An internal combustion cogeneration (cogen) unit produces electricity with an emission factor of about 95 g CO2e/kWh (assuming a 1% methane slip). The justification to pay a premium for biogas-generated electricity in Saskatchewan is stronger than it would be in Manitoba.

It may also be beneficial to supply a mix of natural gas and biogas to an engine where the emission factor of natural gas generated electricity is also cleaner than that from the grid. However, blending the two gasses requires sophisticated control because of their very different Wobbe indices. The Wobbe Index (WI) is a measure of the heating value of fuel gas arriving from the gas line to the orifice where a burner is located. Two gasses with similar Wobbe indices are interchangeable.

The economics improve if the facility already has biogas that can be used to produce electricity. It is not uncommon for an owner to generate their own electricity as a means to protect them from the volatility of the electricity market. The economics of producing electricity further improves if the heat generated is used year round by a heat sink (e.g., chiller, boiler). Dumping heat is a waste of resources.

On paper, some projects can be funded partly by peak shaving. For example, a Class A consumer in Ontario may save more money shaving peaks over 16 hours during the year than providing a steady supply throughout the year. Savings are realized because the consumer is assessed less for the non-consumption part of their bill (i.e., global adjustment).However, it is a risky proposition to base economics decisions over a 10 to 20-year window on something that can be changed by the stroke of a pen.

The biogas universe expanded dramatically when the value of upgraded biogas became divorced from the price of natural gas. A biogas upgrader strips carbon dioxide from biogas along with other remaining contaminants, leaving primarily only methane. Upgraded biogas, referred to as biomethane, is in many circumstances interchangeable with natural gas. Propane can be added to biomethane if the match with natural gas is not close enough for an end user’s application. The carbon dioxide can be stripped from biogas using a number of technologies, including pressure swing adsorption, selective membranes, water scrubbing, chemical scrubbing, physical absorption, and cryogenic separation.

There are now biogas upgrading facilities in Quebec, Ontario and British Columbia.

Biomethane, when injected into the gas grid, is referred to as renewable natural gas (RNG). The commericial value of RNG is no different than that of natural gas, unless the market places a value on RNG’s environmental attributes. The producer must establish a relationship with the gas distributor to convey the gas to a buyer. The producer would obtain a renewable identification number or equivalent for the RNG, inject the RNG into the grid while still retaining (or sharing) ownership, and then sell the RNG to another consumer.

In jurisdictions where there is a mandated renewable component for natural gas, the producer of the RNG could obtain a long-term supply contract similar to the electricity feed-in-tariff contracts. Low carbon economy initiatives such as cap and trade, carbon taxation or emission caps will continue to drive up the revenue from these types of contracts. The savings are more dramatic if the RNG offsets the purchase of diesel or gasoline than if it offsets the purchase of natural gas.

There are a number of standards for RNG, including the Quebec BNQ 3672-100 and Southern California Gas Company Rule Number 30. The tolerance for RNG quality variability decreases as the RNG accounts for a larger portion of the natural gas flowing past the grid injection point. The natural gas grid operates lines at different pressures, much in the same way as the electrical grid does with voltages.

An RNG project can become uneconomical if the injection point is far from the site or the pressure required to inject into the grid at the injection point is high. In cases where the injection point is on a portion of the grid that is dendritic, the consumers downstream of the injection point must consume sufficient natural gas year round to support year round injection.

In the past, biogas was flared, and natural gas was purchased for plant heating. Some plants used the biogas to generate electricity or to drive blowers or pumps. With a preferential rate for renewable electricity or a subsidy for behind the meter generation, many facilities installed combined heat and power engines. A step change occurred because the environmental characteristics of biogas have, in many jurisdictions, divorced the price of RNG from that of fossil fuel natural gas.

In the future, the end users who require a raw material derived from a renewable carbon source may transform biogas from fuel to a sought after raw material, increasing the biogas producer’s revenue even higher.

Patrick Coleman, P.Eng., is with Black & Veatch. This article appears in ES&E Magazine’s June 2017 issue.

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Dr. Jiangning Wu, Dr. Al jibouri, Dr. Konstantin Volchek
(Left to right) Dr. Jiangning Wu, Dr. Al jibouri, and Dr. Konstantin Volchek standing in front of equipment used in the continuous advanced oxidation process developed by Dr. Al jibouri as part of his PhD research. Photo credit: Dwayne Ford, Ryerson University
By Dwayne Ford

During his Masters of Science in Chemical Engineering, Dr. Al jibouri’s university was approached by Iraq’s environmental protection agency with a problem it could not solve. Namely, how to remove high levels of chloride and sulfate ion concentrations being discharged into the Tigris River from an industrial electroplating wastewater treatment plant.

Dr. Al jibouri led a team that designed, manufactured, and installed electrodes to control the addition of oxidizing and reducing agents in the industrial electroplating wastewater treatment plant. By doing so, his team was able to reduce concentrations of chloride and sulfate ions in the effluent to permissible levels.

When Dr. Al jibouri came to Canada and began a PhD at Ryerson University, it was natural for him to pursue his interest in industrial wastewater and he turned his attention to the problem of oil sands pollution in northern Alberta.

Canada’s oil sands occupy a 75,000 km2 area that has the potential for the extraction of up to 900 billion barrels of bitumen. The alkaline hot water extraction process used to remove bitumen from oil sands results in 4 m3 of wastewater per cubic metre of oil produced. Estimates are that, by 2025, extractions underway in the oil sands will lead to 1 billion cubic metres of wastewater. This byproduct is held in settling ponds but this cannot provide long-term protection against seepage into the groundwater and the resulting environmental damage.

The high levels of naphthenic acids in oil sands wastewater led the Alberta government to implement a zero-return policy that requires all wastewater to be stored in settling ponds rather than flowing back into the water supply. Recently, it also passed legislation requiring that all settling ponds be emptied within 10 years of the closure of a mine.

These regulations, which are critical for the protection of the environment, are accelerating the oil sands wastewater crisis. If a solution cannot be found, the oil sands industry could be shut down, which would have an enormous negative economic impact on Alberta and Canada.

The challenge with naphthenic acids is that their compounds are simply too large for microorganisms responsible for biodegradation to digest. So Dr. Al jibouri worked to discover a process that will break down the compounds in naphthenic acids to such a size that they can be biodegraded naturally.

Prior to beginning his research, it was widely known that ozone has the capacity to break down bio-recalcitrant pollutants through oxidation. The difficulty is that ozone-based processes have historically been very expensive. It has never been possible to develop a technique that would be cost-effective when applied at an industrial scale.

Guided by his supervisor, Dr. Jiangning Wu, Dr. Al jibouri undertook the development of a procedure that would allow for optimal control of ozone levels to find the minimum amount of ozone required to break down the bonds in naphthenic acids. They also set out to develop a continuous system for wastewater treatment rather than the batch and semi-batch methods that had been used before.

At the outset, Dr. Al jibouri faced a problem inherent in adopting a novel approach: starting from scratch. For example, there was nothing in the literature about the kinetics of naphthenic acids and ozone. This meant they knew next to nothing about the chemical reactions between them. Without this knowledge, it would not be possible to build an effective wastewater treatment procedure.

This absence of information meant that the first stage of the research involved the painstaking process of determining the minimum levels of ozone required to break down naphthenic acids.

Then, Dr. Al jibouri and Dr. Wu were able to build a procedure that would allow them to use both continuous ozonation processes, where only ozone is used, and continuous advanced oxidation processes in which a combination of ozone and hydrogen peroxide is utilized.

With the new mechanism and procedures established, they undertook the extensive optimal control studies required to discover if they could accurately adjust the amount of ozone used to break down the naphthenic acids.

Results

Pollution levels in wastewater are commonly measured using the ratio of biochemical oxygen demand (BOD) with chemical oxygen demand (COD). If the BOD/COD ratio is higher than 0.5, the water is “clean” enough to be treated like normal municipal wastewater.

With their continuous ozonation process, Dr. Al jibouri and Dr. Wu were able to treat wastewater so well that the outlet stream had a BOD/COD ratio of 0.52 and 93% of the toxicity was removed. With the continuous advanced oxidation process, the ratio was 0.71 and 95% of the toxicity was removed. Remarkably, it only took 2.7 minutes to reduce the toxicity of the wastewater to a level that allowed for it to be returned to the water supply.

Of even further value, Dr. Al jibouri and Dr. Wu discovered that this method can be applied in a wide range of wastewater contexts. They ran a parallel experiment with a fast-kinetic pollutant compound, methyl blue, which is a prevalent side effect of industrial dye and textile processes, and found that their procedure was equally effective. A further potential is to use the method for in situ applications such as remediating perfluorinated foam, which is used in fighting forest fires and causes groundwater pollution.

During their research, Dr. Al jibouri and Dr. Wu developed a novel approach to controlling parameters that reduced operating costs by 35% – 80%, depending on the kinetics of the compounds. These findings were so significant that they did not publish them in the dissertation and have instead applied for a patent.

As a result of their discovery, Dr. Konstantin Volchek of Environment Canada is actively engaged with Dr. Al jibouri and Dr. Wu about applying their technology to the hundreds of controlled sites across Canada where non-biodegradable pollutants need to be treated.

After conducting a two-stage evaluation process, Environment Canada has approved the advanced technology. As a result, Environment Canada has included it in the remediation technology matrix that will be presented to Natural Resources Canada, oil sands companies, and other stakeholders.

Dr. Volchek also plans to explore further collaboration with the other departments of Environment Canada to open channels to market the wastewater treatment process. Possible industrial sectors ideally suited to use Dr. Al jibouri’s water treatment process would be those which produce industrial, non-biodegradable pollutants, and engineering firms dealing with the treatment of industrial wastewaters.

Beyond its industrial applications, Dr. Al jibouri’s water treatment process could also be marketed to provincial and federal government agencies as a way to treat drinking water in some Canadian communities that are affected by non-biodegradable pollutants.

Dwayne Ford is with Ryerson University. This article appears in ES&E Magazine’s June 2017 issue.

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Saskatchewan siting guidelines' impact on wind energy
Saskatchewan's new Siting Guidelines have been designed to enhance environmental protection, provide certainty to future wind energy projects and promote responsible development of utility-scale wind energy. Photo and infographics courtesy of CanWEA.
By Jordyn Allan

Last September, the Saskatchewan Ministry of Environment refused to approve the development of a proposed wind energy project near the Village of Chaplin, Saskatchewan. Not coincidentally, the same day as the Chaplin Project permit was refused, the Wildlife Siting Guidelines for Saskatchewan Wind Energy Projects were released.

The Chaplin Project was Saskatchewan’s first Environmental Impact Assessment (as defined in the Environmental Assessment Act) for a utility-scale independent power producer wind energy project. Environmental concerns, predominantly the concern that the proposed location was too close to a migratory bird flight path, led to the Ministry refusing the project’s environmental permit.

Given that wind energy is relatively new, any guidance that may inform what constitutes the site of a viable wind energy project is beneficial to wind energy developers overall.

Implementation of the Siting Guidelines

The new Siting Guidelines have been designed to enhance environmental protection, provide certainty to future wind energy projects and promote responsible development of utility-scale wind energy in Saskatchewan.

Pursuant to the Siting Guidelines, all proposed wind energy projects must undergo the preliminary environmental assessment screening process to determine whether the project is a “development” under The Environmental Assessment Act. The Act defines a “development” as any project that may have prescribed significant effects on the environment or cause widespread public concern because of potential environmental changes.

If a project falls under the definition of a “development”, it may not proceed until the requisite ministerial approval has been received. A development must undergo an Environmental Impact Assessment intended to inform the Minister of Environment of the potential impacts of the development prior to making a decision.

The Siting Guidelines are a form of planning tool for wind energy developers that set out ministry standards, expectations and advice, to support siting locations in the hopes of fast tracking the Environmental Impact Assessment process. The new Siting Guidelines provide appropriate locations in Saskatchewan for wind energy projects. In doing so, they identify avoidance zones where the risk of ecological impacts or public concerns related to wind energy projects is high.

Pursuant to the Guidelines, a five kilometre buffer zone has been established around designated environmentally-sensitive avoidance areas such as national and provincial parks, ecological reserves, important bird areas, and key rivers and lakes. Areas outside of the avoidance zones are believed to be lower risk sites, better suited for wind energy development. Avoidance zones are also depicted in a map appended to the Siting Guidelines.

Impact for wind energy projects in Saskatchewan

The trial and error approach for wind energy development in Saskatchewan has been replaced with the new Siting Guidelines, which will provide wind energy developers some much needed clarity on how their proposed projects might fare in the environmental regulatory review process.

The Siting Guidelines place a great emphasis on the potential risks to wildlife, particularly bird and bat populations. Therefore, wind energy developers may wish to examine their proposed projects closely to evaluate the impact on migratory corridors or whether there are features of their projects that attract or disrupt flying species.

That being said, with the new Siting Guidelines comes more extensive pre-project planning, approval, and operational, environmental assessment and compliance costs, all borne by wind energy developers. Further, higher standards for low environmental impact sites will likely ensue, for which associated costs to implement such sites will also be absorbed by developers.

In practice, since the Siting Guidelines suggest where and how wind energy development should be done, they will likely become the criteria for regulatory permitting decisions. There is an inference that projects that are inconsistent with the Siting Guidelines will be rejected. Though potentially costly to wind energy developers, this information provided directly by the Minister of Environment, the deciding body itself, is a valuable asset for those parties.

Jordyn Allan is a Student-at-Law with Miller Thomson LLP. This article appears in ES&E Magazine’s June 2017 issue.