Chemical Engineering Imagery

My department put together a nice short video about Chemical Engineering.  It shows some quick images of areas where chemical engineers work, such as alternative energy, pharmaceuticals, water, food processing, and others.  And there are more images about the laboratory research and teaching going on in our facilities.  Have a look and see what you think.

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.

New powder could reduce greenhouse gas emissions | Engineering | University of Waterloo

Some interesting results from my colleague’s research group.  I add some further context below the link…

Researchers at Waterloo Engineering have created a powder that could be used to reduce greenhouse gases at factories and power plants that burn fossil fuels. The advanced carbon powder, developed using a novel process in the lab of chemical engineering professor Zhongwei Chen, could filter and remove carbon dioxide (CO2) from emissions with almost twice the efficiency of conventional materials.

Source: New powder could reduce greenhouse gas emissions | Engineering | University of Waterloo

My Context/Analysis:   Some interesting work in materials science and chemistry.  From the published paper (sorry it’s behind a paywall, but I can read it through the university’s subscription), I can see that the amount of CO2 captured is about 1.6 mmole of CO2 per gram of powder, or about 70 mg/g, at flue gas conditions.  As the paper points out, this is pretty good for CO2 adsorption, but it is not a miracle cure for all of our problems.  To put it in context, in 2016 the U.S. electricity sector emitted something like 1,800,000,000,000 kg of CO2 (from the EPA website).  So, if the powder can capture 70 mg per g it would take about 26,000,000,000,000 kg of powder for one year of capture.  That’s a lot of powder!!  And that’s only for one sector in the U.S. alone (representing about 28% of U.S. CO2 emissions).  So, it’s important to continue doing research, find new things and look at potential applications in a wide range of fields.  But carbon emissions and climate change is a huge problem and there aren’t any easy answers.  Reducing CO2 emissions will generally be better than trying to capture them afterwards, like the three R’s hierarchy (reduce, reuse, recycle).

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

German Baking

Waterloo Region has a long history of German immigration and influence since its initial settlement, leading to place names like Berlin (now Kitchener), New Hamburg, Baden, and local events like Oktoberfest.  Around the area you can find various places with German-style cuisine and products including at the bakery featured in this local news video link:  https://kitchener.ctvnews.ca/video?clipId=1477166   From personal experience, their Christmas Stollen bread and chocolates are highly addictive.  But what does this have to do with chemical engineering? Continue reading

Garbage Research

Over the past month I’ve spent some time on research topics related to garbage.  Or more accurately, energy from waste, sustainable materials management, circular economy issues, reduction and recycling.  To the public, such things may not be as exciting as self-driving cars, but as landfills, oceans, and beaches fill with wastes they are becoming more noticeable and pressing issues.

First, I helped to organize our 5th annual Resource Recovery Partnerships Conference here at Waterloo in late June.  Over two days, we had lots of presentations and networking among academic, industrial and municipal government people discussing various issues related to waste reduction and management.  Shortly after that, I attended the Air & Waste Management Association’s annual conference, held in Hartford CT.  There, I saw a number of interesting presentations on “zero waste”, sustainability, and case studies of projects.  Between these two events I learned a few things that I can summarize below: Continue reading

Artificial Intelligence

Artificial intelligence, or AI, seems to be the popular topic in media these days, and I have had a number of questions about it from prospective students and families over the past year.  The short answer is yes, we do have AI in our Engineering programs.  In fact, we have an “Option in Artificial Intelligence”  available for students in any engineering program.  This is essentially like a “Minor” in the topic, a package of courses related to the field (at Waterloo our terminology is a bit different, so we don’t call it a “minor”).  If you complete the package of courses, you’ll have the designation on your transcript and diploma when you graduate.

Although AI seems new and exciting, the roots and development are actually fairly old, having a basis in  ancient philosophy and mathematics.  Even the more modern versions and applications of AI go back over 50 years to the initial developments in  computational machines.  One misunderstanding is that AI is all about programming, but it is actually highly mathematical at its core.  Programming is just a tool for implementing the math and various algorithms.

Some people may be surprised to know that the mathematical tools and foundations for AI are not even limited to computer science or computer engineering.  My colleagues in Chemical Engineering have been using them for decades for various purposes, and here are a few quick examples with links for further information.

Optimization methods are often a part of chemical plant design, scheduling, cost minimization, and various other things like this example on planning electricity generation.  The control of complex chemical plant processes has been researched using artificial neural networks, like this simpler example of crude oil desaltingBayesian inference methods are employed for dealing with the significant uncertainties in chemical processes, even by me many years agoKalman filter techniques are used to help us handle the noisy data coming from chemical processes, including this example from biotechnology.  And there are lots of other examples, just in Chemical Engineering alone, not even looking at Civil, Mechanical and others (where I know they also use these advanced mathematical techniques).

Just another example of how broad and diverse the engineering fields are, and how concepts and tools are spread and shared across all these disciplines.

Problem Lab

Research on Infection Control

A tragic statistic tells us that of all the people admitted to hospitals for various reasons, about 10% will get sick from an infection picked up in the hospital, something called a Healthcare Acquired Infection (HAI) or nosocomial infection.  Of these, about 5% will die from it, which corresponds to about 10,000 Canadian deaths per year.  The additional costs of treating these infections add up to between $4 and $5 billion in Canada.  The consequences are proportionately similar in other regions such as the U.S. and Europe.  The increases in antibiotic resistance in bacteria are adding to the problem.

Hospital infection control has traditionally focused on hand-washing, isolation, and cleaning and disinfection protocols to minimize the spread of “germs”.  However, there is a limit to how far these can go, since they rely on consistent human behaviour, which is naturally inconsistent.  Therefore in recent years there has been more focus on “engineered” approaches to infection control.  To this end, my research group and I have been working with the Coalition for Healthcare Acquired Infection Reduction (CHAIR) to help develop and test materials, processes and devices that may help in the fight against HAIs.

One project we finished tested the effects of an automated ultraviolet light (UV) disinfection device placed in patients’ bathrooms to control the background bacterial contamination between uses.  The paper can be read on this website.  The data indicated that it was possible to dramatically lower bacterial contamination levels with this device, which was nice to see.

In other work, we’ve been collaborating with Aereus Technologies to develop new antimicrobial materials and coatings for use on hospital “high-touch” surfaces and equipment.  This doesn’t eliminate the need for surface cleaning and disinfection, but it helps to kill the germs that land there between cleanings and thus reduce the chance for spread of infections.

In other more basic research, we’ve been collaborating with various other professors here at Waterloo to identify novel antimicrobial materials or detection methods for contaminants.  For example, with Prof. Michael Tam’s group we’ve published a couple of studies on antibacterial cellulose materials (abstracts are available here and here).  We recently published another paper on detection of bacterial contamination in water using an interesting combination of enzymology and nanotechnology.

If you’re wondering what this has to do with Chemical Engineering, well basically this is chemical engineering.  Working with production and characterization of materials, interactions of materials, life science and biochemistry…those are all part of chemical engineering education and possible career paths.

Hopefully over the next few years this HAI problem will begin to see some progress and we can continue to contribute to the solutions.