Xylem-MixingBestPractices
Authors Posts by Peter Davey

Peter Davey

312 POSTS 3 COMMENTS

0
Cigdem Eskicioglu is a professor of engineering at UBC's Okanagan Campus. Photo credit: UBC Okanagan.

Researchers from University of British Columbia’s Okanagan (UBC) campus say they have developed a new way of making wastewater treatment dramatically safer and better smelling by using common and inexpensive chemicals.

Cigdem Eskicioglu, an associate professor with UBC Okanagan’s School of Engineering, says anaerobic digestion, used by many wastewater treatment plants, produces toxic, corrosive and extremely odourous sulfuric gases, like hydrogen sulfide. This prevents some communities from adopting beneficial anaerobic treatment methods.

“There are strong arguments for wastewater treatment facilities to use anaerobic digestion, but the equipment required to control odour and to make the biogas safe has been an expensive barrier,” said Eskicioglu, co-author on the study. “We’ve discovered a formula that seems to solve that problem.”

Eskicioglu, postdoctoral research fellow Deniz Akgul, and PhD student Timothy Abbott tested novel combinations and doses of common commercial chemicals, called metal salts, during the fermentation process to see if the offensive smells could be controlled. According to UBC, the results were dramatic.

“Not only were we able to reduce the production of sulfuric gases by 93%, to the point that they became nearly imperceptible, but we unexpectedly discovered that pathogenic fecal coliforms in the digested sludge were reduced by 83%,” says Abbott. “Digestion performance and biogas production remained completely intact and the leftover material was much safer for eventual use in applications such as agricultural fertilizers.”

The researchers also discovered that adding metal salts significantly improved their ability to remove water from the digested sludge, which is a necessary step for final disposal.

Abbot said that, while metal salts have long been used in wastewater treatment to control smell, it’s their unique doses and point of addition during the fermentation process that seems to be particularly effective in controlling odour and pathogens. He also points out that the cost of adopting their technique is minimal.

“We estimate that a medium-sized treatment facility, like the one in Kelowna, BC, would need to spend only $10,000 annually on chemicals,” he explains. “With such a low-cost and effective means of controlling sulfuric gases and pathogens, wastewater managers could realize all the benefits of anaerobic digestion without the considerable costs of installing and maintaining traditional biogas sulfur scrubbing equipment.”

The study was published in Science of The Total Environment. To read the original news release, click here.

0
Aerial view of a small lake near the city of Clear Lake, Iowa, which represents typical landscapes surrounding the lakes in this study. The study authors hypothesize that very high nitrogen levels, often >10 mg/L, suppress high chlorophyll (algae) concentrations.

Lakes in agricultural areas surrounded by fields often appear green in colour due to nitrogen and phosphorus in fertilizers. Excess fertilizer that runs into lakes helps fuel the growth of algae and cyanobacteria, which can turn lakes the color of pea soup.

Yet, when scientists looked at 13 years of data from 139 lakes in intensively agricultural areas of Iowa they saw lakes that were surprisingly clear despite extremely high nutrient concentrations.

In a study published on October 9, 2017 in the journal Inland Waters, scientists from the University of Minnesota Duluth and Minnesota Sea Grant report that some lakes were so excessively fertilized that most of that algae and cyanobacteria containing the green pigment chlorophyll were killed.

“One of the dangers here is mistaking increased water clarity for improved water quality,” said Chris Filstrup, lead author of the study and a research associate with the UMD Large Lakes Observatory and Minnesota Sea Grant. “In fact, the water quality in these instances is worse than in lakes that have more algae, yet lower levels of nutrients.”

According to Minnesota Sea Grant, regulatory agencies have often used water clarity as an indicator of water quality. The results of this study suggest that approach may not necessarily work in all regions and defies the generalization that even extreme concentrations of phosphorus and nitrogen continue to fuel algae growth.

“In some of the Iowa lakes in our study we noted phosphorus levels 10 times what we’d expect to see in a northern Minnesota lake,” said Filstrup. “We were astonished to see that the nitrogen levels were more than 30 times higher.”

Such extreme nutrient levels appear to destroy existing algae and cyanobacteria, resulting in an increase in water clarity. The concept is similar to the way applying too much fertilizer on land can damage, if not kill, plants and render soil barren.

“We thought that the low appearance of algae at high nitrogen concentrations might be due to imbalances of other nutrients, or too much shade for algae to grow, or that some algae are less green or that zooplankton eat more algae when there’s a lot of nitrogen,” said co-author John A. Downing, director of Minnesota Sea Grant, a scientist at the UMD Large Lakes Observatory and a professor in the UMD Department of Biology. “But none of those hypotheses panned out. The only explanation that makes sense, so far, is that high nitrogen is bad for algae.”

The reduction in algae is likely the result of the interplay of phosphorus, nitrogen, the landscape and sunlight, which, when combined, causes the excessive nitrate particles in the water column to form reactive oxygen species that damage or kill algae by bursting their cell walls and membranes, say Filstrup and Downing.

“You might think of it like hydrogen peroxide,” said Filstrup. “Pouring hydrogen peroxide on a cut causes bacteria to burst. That’s why it fizzes. In lakes, the reactive oxygen species that can form from nitrate don’t fizz but they can destroy organic matter, potentially including phytoplankton.”

As demand for agricultural products continues to grow and with that an increased use of fertilizers, the authors hope this study will serve as an instructive example for other agricultural regions that are experiencing or are at risk of extreme nutrient loading.

This article was modified and reprinted with permission from Minnesota Sea Grant and the University of Minnesota Duluth. To read the original article, click here.

0
news icon

SUEZ announces that, together with Caisse de dépôt et placement du Québec, it has completed the acquisition of GE Water & Process Technologies (GE Water) for $4.72 billion enterprise value in an all‐cash transaction, effective as of September 30, 2017.

Former President and CEO of GE Water, Heiner Markhoff, will lead the new “Water Technologies & Solutions” business unit created in connection with the acquisition. This unit combines the former GE Water business with SUEZ’s industrial service activities.

SUEZ also announced new contracts across various industries as well as new product lines. These were:

  • A 600,000 litre per day wastewater treatment system for BP’s Tangguh Liquefied Natural Gas (LNG) plant in West Papua, Province of Indonesia. The system will process high salinity water and use a flotation clarification process and activated carbon filter to remove free and emulsified oil, chemical oxygen demand, biochemical oxygen demand and non-dissolved solids.
  • The design and supply of wastewater treatment systems for Louisville Gas and Electric Company and Kentucky Utilities at their coal-fired power stations near Louisville, Kentucky. These systems will treat flue gas desulfurization wastewater produced by the power stations.

Product news included:

  • The launch of a next generation ozone system for water treatment, the ozonia® M;
  • A compressible media filter called FiltraFast™ solution; and
  • A new laboratory TOC analyzer to optimize organic carbon detection.

To learn more, visit: www.suez.com/en/News

0
drinking water picture

The Chief Drinking Water Inspector’s Annual Report provides information about the performance of Ontario’s regulated drinking water systems and laboratories, drinking water test results, and enforcement activities and programs.

The 2016-2017 annual report, released on October 6, 2017, highlighted results for Ontario’s regulated drinking water systems, including:

  • 99.8% of drinking water tests from municipal residential drinking water systems met Ontario’s drinking water standards. These municipal residential drinking water systems serve more than 80% of Ontario’s population.
  • 99.4% of municipal residential drinking water systems received an inspection rating greater than 80%, with 70% receiving an inspection rating of 100%. Inspection ratings show how well the systems are operating and meeting regulations.
  • 98% of flushed test samples from schools and child care centres met the province’s standard for lead in drinking water.

According to the Ministry of Environment and Climate Change (MOECC), Ontario uses a multi-barrier approach to protect drinking water through legislation, health-based standards, and regular testing, trained operators, regular inspections, source water protection program and transparent reporting.

The 2016-17 Report at a glance
  • The Inspector’s report states that over the past five years, Ontario has seen progressively positive results, including a steady decline in the proportion of high-risk systems (11.59% in 2016-17 down from 16.65% in 2012-13). As of March 31, 2017, 75.42% of small drinking water systems are now categorized as low risk.
  • A decline of 20.60% in total number of adverse water quality incidents was observed between 2012-13 (1,471) and 2016-17 (1,168). The number of small drinking water systems that reported an adverse water quality incident for the same period also declined by 18.24% from 1,173 in 2012-13 to 959 in 2016-17.
  • 97% of over 99,000 drinking water samples submitted from small drinking water systems during the reporting year have consistently met Ontario Drinking Water Quality Standards.
  • As of March 31, 2017, 18,942 risk assessments have been completed for the approximately 10,000 small drinking water systems.
  • Over 88% of systems are categorized as low/moderate risk and subject to regular re-assessment every four years, while the remaining systems, categorized as high risk, are re-assessed every two years.

According to the MOECC, Ontario has approximately 10,000 small drinking water systems regulated under the Health Protection and Promotion Act. These systems are located across the province in semi-rural to remote communities and provide drinking water where there is no municipal water supply.

Click here to read the Inspector’s 2016-2017 annual report.

0

The Water Environment & Reuse Foundation (WE&RF) and Water Research Foundation (WRF) announced that their respective boards voted unanimously to integrate the two organizations into one research foundation on October 10, 2017.

Beginning on January 1, 2018, the new organization will be led by a single board of directors comprised of the directors from the two organizations with co-chairs Chuck Murray and Kevin Shafer and co-CEOs Melissa Meeker and Rob Renner. The new organization will be called “The Water Research Foundation” and will have approximately 1,200 subscribers, 2,300 research studies, and a $700M portfolio.

According to the WRF, the main benefits of integration are:

  1. Provide the water community with access to an expanded collection of water research;
  2. Leverage funding more successfully;
  3. Share a greater knowledge base; and
  4. More effectively communicate new results and research needs with federal and state regulators.

“The decision to integrate these two organizations is a great victory for the water community,” said Rob Renner, CEO of WRF. “The new organization will leverage resources and funding to solve the water sector’s research needs in new and exciting ways.”

“Harnessing the collective passion of our staffs, volunteers and supporters to focus on research which meets the needs of all water professionals will provide an outstanding benefit for our subscribers,” said Melissa Meeker, CEO of WE&RF. “We are looking forward to the challenge.”

Additional information is available at www.werf.org and www.waterrf.org.

0
news icon

Teck Coal Limited pleaded guilty on October 5, 2017, to three counts of contravening the Fisheries Act. The Provincial Court of British Columbia ordered the company to pay a penalty of $1,425,000, which will be directed to the federal Environmental Damages Fund. Additionally, Teck Resources will post information regarding this conviction on its website.

According to Environment and Climate Change Canada (ECCC), Teck Coal’s Line Creek Operations is located 25 kilometres north of Sparwood in southeastern British Columbia. On October 17, 2014, ECCC enforcement officers launched an investigation following a report that fish had been found dead in ponds connected to Line Creek.

During the investigation, ECCC said its enforcement officers found that the effluent from the water treatment facility going into Line Creek was deleterious to fish. Numerous dead fish were found in the Line Creek watershed as a result of this discharge, including Bull trout. Bull trout are identified as a species of special concern in this area of British Columbia.

Line Creek is identified by the Government of British Columbia as part of a “Classified Water” system. This provincial classification means that the water system is seen to have a high fisheries value and it requires special fishing licenses.

To read the original press release, visit: www.ec.gc.ca

0
news icon

Sherritt International Corporation (Sherritt) pleaded guilty in the Provincial Court of Alberta on October 3, 2017, to three counts of contravening the Fisheries Act. Sherritt was sentenced to pay $1,050,000, of which $995,000 will be directed to the Environmental Damages Fund. As a result of this conviction, the company’s name will be added to the Environmental Offenders Registry.

According to Environment and Climate Change Canada (ECCC), the Coal Valley Mine, which was owned by Sherritt from 2001 to 2014, is an open-pit coal mine located 90 km south of Edson, Alberta. On August 3, 2012, ECCC enforcement officers visited the mine in response to a spill report, and they determined that effluent being deposited from a wastewater pond was deleterious to fish.

The wastewater ponds at the Coal Valley Mine collected surface water that was treated with a chemical flocculant to remove suspended sediment before being discharged. Both suspended sediment and an excess of flocculant can be toxic to fish.

Enforcement officers subsequently issued a direction under the Fisheries Act, which resulted in the deposit being stopped. Further investigation by ECCC determined that there were two previous releases of deleterious effluent from wastewater ponds, on July 27, 2011.

The releases went into tributaries of the Athabasca River, including the Erith River portions, which are identified by the Government of Alberta as “ecologically significant habitat” for Athabasca rainbow trout, a species at risk.

To read the original press release, visit: www.ec.gc.ca

0
Canada and Germany. Adobe Stock, Aleksandar Mijatovic.

The Public Infrastructure Engineering Vulnerability Committee (PIEVC) Protocol will be used in 14 new countries to assess climate risks and vulnerabilities across a wide range of infrastructure systems, thanks to a new Canadian-German partnership.

Engineers Canada and the German International Development Agency (GIZ) announced they have partnered on a 32-month project that will see Engineers Canada’s PIEVC Protocol used to conduct climate vulnerability assessments on infrastructure in three GIZ partner countries—Brazil, Costa Rica, and Vietnam—as well as in the Nile Basin Initiative, a consortium of 11 East African countries.

According to Engineers Canada, the PIEVC Protocol facilitates initiatives that provide clear guidance to professional engineers and geoscientists to support the design, construction, maintenance and regulation of safe, reliable and financially sustainable public infrastructure to address the risks of a changing climate.

Throughout the Engineers Canada-GIZ  project, the PIEVC assessments, conducted as case studies, will engage local engineers and other disciplines working as a team. These case studies will build capacity through a “learn-by-doing approach” that will integrate the Protocol into climate services and infrastructure planning in those countries.

Engineers Canada said it will provide PIEVC and climate experts to support the local project teams and deliver several workshops in each location, as well as ongoing advice, support, and review as the local teams work through their respective case studies.

The intended outcome of the use of the PIEVC Protocol in this project is to enhance the capacity of local engineers to carry on this work as part of enhanced in-country engineering and climate services to support infrastructure investment decision-making.

Learn more about the Public Infrastructure Engineering Vulnerability Committee Protocol.

To read the original news release, visit: www.engineerscanada.ca

0
Atrazine is used extensively in Canada as a pre- and post-emergence weed control agent, primarily for corn but also for rapeseed. Photo: Adobe Stock, Faustasyan .

Atrazine is used extensively in Canada as a pre- and post-emergence weed control agent, primarily for corn but also for rapeseed. Photo: Adobe Stock, Faustasyan .
Atrazine is used extensively in Canada as a pre- and post-emergence weed control agent, primarily for corn but also for rapeseed. Photo: Adobe Stock, Faustasyan.

Atrazine, widely used as a weedkiller, is known to have harmful effects on aquatic wildlife and presents a risk to human health by altering the action of certain hormones. According to Health Canada, it (or its dealkylated metabolites) is one of the most frequently detected pesticides in surface and well water. Health Canada’s maximum acceptable concentration for atrazine in drinking water is 0.005 mg/L. Contamination has been reported in British Columbia, Nova Scotia, Prince Edward Island, Quebec, Ontario and Saskatchewan.

In a study published recently in Water Research, a team of researchers led by Institut national de recherche scientifique (INRS) professor Patrick Drogui compares various processes used to degrade atrazine. The team demonstrates that photo-electro-Fenton (PEF), a hybrid process, is particularly effective for removing low concentrations of atrazine and its byproducts in surface water sampled from agricultural areas. The study marks the first use of PEF in these conditions.

According to a press release, the researchers used a combination of electrochemical, photochemical, and photoelectrochemical processes together in a single reactor. The results were conclusive: over 99% of the atrazine was eliminated after 15 minutes of treatment. After 45 minutes of treatment, the byproducts were all in concentrations lower than the detection limit in synthetic samples. In surface water, anywhere from 96% to 100% of the byproducts were eliminated. The team was even able to observe each phase of degradation for the atrazine byproducts.

“These days, the challenge is to develop low cost industrial technologies that can be used to treat large volumes of water and simultaneously remove micropollutants like pesticides and their metabolites, which can be more toxic than the original compounds,” coauthor of this study Professor Patrick Drogui said.

Researchers say that although PEF is a clean, effective technology, it will take some more work to combine it with a biological treatment process in a water treatment plant and make it more energy efficient. Further research is needed to get a better understanding of how the atrazine degradation mechanisms identified in the study function in the presence of organic matter.

The study is published in Water Research under the title “Removal of atrazine and its byproducts from water using electrochemical advanced oxidation processes.

0
news icon

Environment and Climate Change Canada (ECC) made environmental enforcement announcements earlier this month relating to the Canadian Environmental Protection Act.

Industrial-supply company pleads guilty to contravening the Ozone-Depleting Substances Regulations, 1998

Fastenal Canada Ltd., of Kitchener, Ontario, was fined $265,000 after pleading guilty in the Ontario Court of Justice to two counts of contravening the Ozone-Depleting Substances Regulations, 1998 made pursuant to the Canadian Environmental Protection Act, 1999. According to ECC, the fine will be directed to the Environmental Damages Fund.

Enforcement officers from ECC investigated Fastenal Canada, revealing that, from November 2012 to January 2015, the company imported and sold aerosol products containing hydrochlorofluorocarbons, a regulated ozone-depleting substance.

As a result of this conviction, the company’s name will be added to the Environmental Offenders Registry.

For more information, visit: www.ec.gc.ca

Auto paint and supply company fined for environmental violations

Fine Auto Paints and Supplies Ltd. of Scarborough, Ontario, was fined $25,000, after pleading guilty in the Ontario Court of Justice on September 13, 2017 to one count of contravening the Volatile Organic Compound Concentration Limits for Automotive Refinishing Products Regulations, under the Canadian Environmental Protection Act, 1999. According to Environment and Climate Change Canada, the fine will be directed to the Environmental Damages Fund (EDF).

An investigation by ECC enforcement officers revealed that the company had sold automotive refinishing products that contained volatile organic compounds (VOCs) in excess of the allowable limit.

VOCs are primary precursors to the formation of ground level ozone and particulate matter which are the main ingredients of smog. Smog is known to have adverse effects on human health and the environment.

As a result of this conviction, the company’s name will be added to the Environmental Offenders Registry.

For more information, visit: www.ec.gc.ca