Cruise Ship Air Quality

An interesting news story about the measurement of air quality on cruise ships appeared recently.  Specifically, it dealt with the concentration of ultrafine particulate (UFP) matter in the air on four cruise ships, measured by a researcher from Johns Hopkins University.  UFP is invisible matter with diameters of around 100 nanometres (nm), which is about  1,000 times smaller than a human hair, and it is implicated in airway inflammation and effects on other organs in the human body.  Being interested in air quality, I looked up the actual study report which you can also read here.  Here is my take on the work and meaning… Continue reading

Ontario’s Refundable Fee Plan

The Ontario government recently announced a 10% tuition discount, as I mentioned earlier.  Along with that, they also announced that many fees will have to be made refundable for any student that doesn’t want to pay them.  The theory is that it will give “students more choice over the fees they pay” and save students money on top of their 10% discount.  It’s quite unusual for governments to start micro-managing university fees, many of which were set up to address local conditions and concerns with student support via a referendum.  There is an exception in the announcement however, and fees that “fund major, campus-wide services and facilities or fees which contribute to the health and safety of students are deemed mandatory”.  These mandatory fees include walksafe programs, health and counselling, athletics and recreation and academic support.  So, I was interested in how this affects engineering students at Waterloo, and compiled a list of fees (to the best of my ability).  It’s complicated but here they are with some comments and observations. Continue reading

Cannabis Air Emissions



With recent moves to permit sales of cannabis in Canada and some U.S. states, commercial operations are popping up in various locations.  Whenever new industries emerge, there are often new environmental impacts to consider and air pollution seems to be an increasingly common problem with cannabis too.  Not from smoking, but rather from the greenhouse operations where it is grown under lights in high-density conditions to save space.  It turns out that these intensive grow operations can have vented air emissions that are rather smelly, as this one news item describes.

Like all plants, cannabis emits volatile chemical compounds at various stages in its growth.  Some work has been reported in research literature, identifying over 200 chemicals in the air, although I suspect that paper missed a lot of odorous sulfur compounds that are often associated with “skunky” smells.  A lot of the odor compounds are terpenes or their relatives (e.g. limonene, pinene, linalool), and the paper mentions cymene, benzaldehyde, nonanal, and decanol as key odor chemicals.  None of these compounds are particularly hazardous (at least at the normally low concentrations found around plants).  None of them are specific to cannabis either.  Lots of them are produced by various plants, in varying amounts and combinations.  A lot of plant-based essential oils that you can buy contain similar chemicals.

The environmental issue arises if the odor interferes with the neighbouring property and their ability to use and enjoy their property.  The Ontario government website has some information about odors and property-owner rights .  Under Ontario’s Environmental Protection Act (Section 14) odor-emitting industries can get into legal trouble because they are emitting a “contaminant” that causes an “adverse effect”.

From an engineering point of view, the control of odorous emissions like this is not unlike many other industries with odour concerns, like sewage treatment plants, rendering plants, some food manufacturers, and some chemical manufacturers.  The first step is containment, so that odor emissions are not just leaking out of the buildings from a multitude of locations.  If everything can be efficiently captured in one or two well-controlled ventilation systems, then emissions controls can be applied to those vent streams before they discharge into the environment.

It’s not clear at this point what type of emission controls are best for both efficiency and cost points of view.  Usually there are several possible solutions, so engineers have to figure out which one is the most cost-effective.  Standard approaches to odor control run a range of technologies from wet scrubbing to activated carbon capture, to biofiltration and possibly photochemical oxidation.  High temperature thermal oxidation is another option, but probably overkill and too expensive for this application.  One solution may not fit all commercial operations either.  Each location would need a thorough engineering analysis and assessment for a good recommendation, which is something done by chemical and environmental engineers (and some mechanical engineers too).  Companies that rushed into production without doing these assessments may get stuck with expensive retro-fits once the Ministry of Environment comes knocking.

So, with every new “industry” there are issues that come up that may or may not have been anticipated by the business people.  Those issues will keep regulators and engineering consultants busy for a while.

Ontario’s New Climate Change Plan

The new Ontario government recently released their plan to tackle carbon emissions and climate change.  This comes after scrapping the previous government’s relatively new cap-and-trade scheme that was set up in collaboration with Quebec and California.  Below I’ll give a detailed analysis of various parts of the plan, but here is my high level overview.  There are some promising bits and pieces (without knowing a lot of details yet), but it is relatively unambitious and somewhat odd in its approach.  This new government has generally focused on reducing regulation and taxpayer-funded spending, but this plan implements additional regulations and uses tax money to subsidize industry.  This seems inconsistent.  If you want to see the plan and comment, here is the link.  Now for my detailed analysis… Continue reading

Ontario Climate Change Plan Input

The new Ontario government quickly trashed the beginnings of an approach to reducing carbon emissions and climate change, i.e. a “cap and trade” system in collaboration with California and other provinces and states.

Now the government is looking for input into their promised new and improved approach, which you can provide at .   It’s open until November 16 2018.

A recent report has re-confirmed that we only have until about the year 2030 to substantially reduce carbon dioxide emissions, before the goal of keeping the global average temperature increase to less than 1.5 degrees Celsius becomes physically impossible.  (This is actually not surprising news since it’s been known for many years in the scientific literature, while the world at large continues to do nothing substantial).

Young people, and parents or grandparents of young people, should be commenting because these are the ones who will be inheriting the problem and all of its consequences over the next few decades.

Ignore the Rankings

A group affiliated with the Stanford University Graduate School of Education has put out an interesting analysis and report “A ‘Fit’ Over Rankings:  Why College Engagement Matters More Than Selectivity”.   Basically it says that college rankings are not a useful indicator for quality or outcomes from a student’s perspective.  Students and parents would be better off ignoring rankings when choosing a college or university.  “Selectivity” (how hard it is to get an offer) is not a reliable indicator either.

What is important is “engagement” inside and outside the classroom.  Opportunities for internships (or co-op), mentors, long-term projects (maybe like student design teams?) are all examples of “engagement” that they cite in the report.  There are lots of other interesting details and observations, so I highly recommend having a look at it if you’re thinking about applying to university.

AIChE Fellow Frances Arnold Is One of Three Winners of 2018 Nobel Prize in Chemistry | AIChE

Nice to see a Chemical Engineer receive a Nobel prize, for work on random mutagenesis for industrial enzyme selection and improvements.  My PhD work was in enzyme applications, though not this particular area.

Dr. Arnold’s research has produced methods now routinely used to create new catalysts. Her work has led to new enzymes for pharmaceuticals, sustainable biofuels, and other environmentally friendly products.

Source: AIChE Fellow Frances Arnold Is One of Three Winners of 2018 Nobel Prize in Chemistry | AIChE

Life extending technology |

A story at the link below about a company started by one of our nanotechnology engineering graduates (and a Masters in Mechanical Engineering, according to his LinkedIn page).  The technology is based on SPR, or Surface Plasmon Resonance, and interesting material property that appears at the nanoscale.  Some of my research work is based on this phenomenon, and this seems like a nice piece of equipment.

Kitchener startup’s ‘life extending’ technology helps researchers study disease and develop new medicines

KITCHENER — Ryan Denomme pursues cutting edge science from inside an old factory building where his grandmother used to work.

Denomme is the co-founder and chief executive officer of Nicoya Lifesciences, which recently launched the second version of its desktop device that measures interactions between some of the most important building blocks in the human body — proteins.

Source: Life extending technology |

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