Plastic bags and nuclear waste

Plastic bags, invented around 1960s have become indispensable in our lives for shopping, groceries, organizing home items, garbage collection. The low production cost and convenience brought to us by the plastic bags do come with environmental concerns that as a kind of litter they can last centuries to degrade and improper disposal can lead to land/water pollution. The more sensible use of plastic bag of course is to reuse it multiple times before final disposal, or have good recycling scheme, both reducing the demand of producing new plastic bags and their waste volume/mass.

If we replace the words ‘plastic bags’ with ‘nuclear fuel’ in the above paragraph (and a few other words of applications), we can clearly draw analogies between the two. Nuclear energy is seen as a relatively cheap and clean source of energy. Yet it does cause environmental concerns as its spent fuels last thousands of years. It is however little known to the public that, nuclear spent fuel recycling technologies do exist and methods to ‘burn off’ long-lived radioisotopes can reduce the toxicity of nuclear wastes to hundreds of years.

Nuclear energy though technically more complex, is just another invention by our society to increase our standards of living, like plastic bags have done. The intention is good yet the consequences of our actions weren’t entirely known from the beginning. Only by first recognizing and admitting the problems (long-lived and toxic nuclear wastes), then we can properly tackle them and show that nuclear energy can be safe and sustainable, and play a key role in giving an energy boost to propel our society forward into the future.

Advertisements

About Canada’s Oil Sands

Notes taken from the booklet produced by the Canadian Association of Petroleum Producers (CAPP) and current as of June 2011.Image

  1. The world’s 3rd largest oil reserves are found in Canada.
  2. Oil sands constitute 97% of these reserves in Canada.
  3. Oil sands = a natural mixture of sand, water, clay and bitumen.
  4. Bitumen is oil that is too heavy or thick to flow or be pumped without being diluted or heated.
  5. At 50F, bitumen is as hard as a hockey puck.
  6. Three oil sands deposits are in Athabasca (Alberta/Saskatchewan), Peace River (Alberta) and Cold lake (Alberta). See: http://goo.gl/maps/hU2IM
  7. Two methods to recover the oil are: 80% Drilling (in situ): steam assisted gravity drainage drilling and cyclic steam stimulation drilling. 20% Mining: dig, crush, extract, recycle tailings.
  8. In 1980, Canada production in barrels/day: 0.1M oil sands; 1.5M crude oil including oil sands
  9. In 2010, Canada production in barrels/day: 1.5M oil sands; 2.8M crude oil including oil sands
  10. In 2009, 97% of Canada’s energy exports went to US markets.
  11. Canada produces 2% of global greenhouse gas emissions with a 0.5% of world’s population.
  12. GHG by countries: China (24%), US (18%), OECD EU (17%), Non-OECD Europe & Eurasia (9%), India (5%), Japan (4%)
  13. In 2009, oil sands’ total GHG emission were 45 M tonnes, accounting for 6.5% of Canada’s GHG emission.
  14. Current carbon price in Alberta is $15/tonne. Oil sands producers are required to pay into a technology fund if they do not meet the emission reduction targets.
  15. CCS =carbon capture and storage
  16. The Wood Buffalo Environmental Association monitors the air in oil sands region 24/365.
  17. Alberta government allocates 7% of water allocation to oil sands, and 11% to municipal and 44% to irrigation/agriculture.
  18. Drilling (in situ) requires on average 0.5 barrels of fresh water for every barrel of oil produced.
  19. Mining requires 2 to 4 barrels of fresh water for every barrel of oil produced.
  20. Oil sands producers recycle 80 – 95% of water used.
  21. Tailings = leftover mixture of water, sand, clay and residual oil after oil is separated from sand.
  22. Tailing points are large engineered dam and dyke systems designed to store tailings.
  23. Seepage such as ditches around tailings to pump water back into the tailings ponds.
  24. Fine tailings is the middle layer in the tailing ponds (below water, above coarse sand) and a combination of water and clay. Separation and dry out of fine tailings can take up to 30 years without acceleration technology.
  25. Residual oil can be found floating on the surface of most tailing ponds and poses a threat to birds that land on the ponds.
  26. Active mining footprint = 260 sq miles, about the city area of Austin, Texas.
  27. Alberta law requires all lands disturbed by oil sands operations be reclaimed. All companies are required to develop a reclamation plan that spans the life of the project.
  28. Go to www.oilsandstoday.ca for more information

can we all accept nuclear?

My personal introduction to nuclear engineering is pretty much by chance. Before taking a 4th year undergraduate engineering course in nuclear, I never really thought much about this type of energy. I was also guilty of knowing only very little about the atomic bomb. The course I took was divided into two parts. First on the types of radioactive decay, radiation dose, calculations of energy produced per kg mass of Uranium, etc. The second part was more on neutron transport theory, the multiplication factor and reactivity effects.  And just after one course, I was convinced by the robust understanding of physics and marvelous engineering principles that nuclear power is run on and that it will be able to support humanity’s endeavour to survive, flourish and sustain in the centuries to come. In retrospect, a single university course has made me steer the next three years of my life into the direction of nuclear energy and I do not regret my choice at all.

In the midst of all the debates about whether nuclear energy is really right for mankind, or is a purely evil creation that will leave our planet earth inhabitable for our future generations, I who is studying nuclear energy believe the latter is avoidable and wonder if science and facts can really change ANYone’s opinion about nuclear energy. There is no lack of clear information made available by authoritative sources such as:

Often we’re told to trust the experts and we’re given the facts and explanations. But I suspect, only certain types of people are able to absorb these facts and science, no longer uninformed will accept that nuclear energy is safe and crucial in providing enough energy for our expanding appetite and demand of electricity. The rest of the population, no matter how many accurate facts and cost/benefits analyses are given to them, simply cannot be convinced. As summarized nicely in this blog post on Brave New Climate: http://bravenewclimate.com/2011/04/15/who-has-changed-their-mind/, it is interesting to see who’s been “converted” to pro-nuclear or neutral from anti-nuclear. In theory, all these people could receive the same facts and figures about nuclear and the anti-nuclear group could raise issues that prevent them from accepting nuclear, while the pro-nuclear group could answer those issues that convinced them of a nuclear future. If it was all and only about facts and educating the public,  the pro-nuclear power group would prevail. But this hasn’t been the case.

The answer to “how to increase public acceptance of nuclear power” may not simply lie in providing accurate facts any more. When I ask myself why I am drawn to nuclear power, I attribute my affinity to nuclear to a bit of my personality and life philosophy. I’m practical and I take risks in life. Though I have visions and dreams, I’m realistic and not an idealist. If I apply my approach to life to nuclear power, I think it’s why I can accept that there are risks in running nuclear power plants, but they are acceptable risks. I hope for a future where the last quarter of the world’s population will have electricity, but realistically it will not be generated by solar panels or wind farms which have not consistent outputs and require large amount of lands. As for the nuclear wastes, I think a bit of land reserved for their disposal is insignificant, in comparison to the much greater impact  on geological areas lost due to rising sea level or climate abnormalities. Finally, the threat of an atomic war is present but nuclear power cannot be blamed; forbidding nuclear energy production will not make the threat disappear either. The root causes of many conflicts bury deeply in the lack of resource and energy security, more than religious differences. Why should nuclear be the scapegoat when it can actually provide energy security and independence?

The solution to making nuclear power more acceptable is not to aim for full acceptance. Aim for 50% of the population, in which influential individuals or groups of individuals who think in similar ways as people who already support nuclear.  Give them the facts and they can be “converted” more easily from anti- or neutral to pro-nuclear. Once we have over 50% of the public, the support is enough to keep nuclear going. In case that we cannot find more that 50% of the public, our planet will only have to run on solar panels and wind farms (if not coal, oil and gas). If we could still prevent climate change without nuclear and continue to have technological advances, we could wait for the day that our intergalactic transport vehicles were powered by fusion energy or anti-matter.

Matter of hope or trust in the days to come in nuclear age

Can you imagine we might live to see the day of a nuclear weapon testing in this century? The unmistakable mushroom cloud engulfing the vast sky and the sense of death permeating in non-stoppable speed. It is to me, unthinkable that any nation would want to commit something so destructive and have that engraved in its history forever.

Therefore, I was extremely pleased to read that:

Iran, facing growing international pressure over its nuclear program, called for more talks with the UN nuclear watchdog on Tuesday and condemned production of atomic weapons as a “great sin.” –  28.02.2012, National Post

Do I believe the words of the Iranian politicians? It’s my wish that they speak their mind and true belief.  I support the peaceful utilization of atomic energy in terms of electricity production. But nuclear bomb as a weapon of mass destruction is condemned unconditionally.

One year to Fukushima and future of nuclear power

Today our research group was visited by a Scientific Advisory Committee. As for the students, we were also seated down with the chair of this committee to talk about our experiences at the research group this year. Let me tell you first that, the group of attended students consisted of 2 PhD candidates (I’m one of the 2) and 3 Master’s students. The meeting went on for more than an hour and I really enjoyed listening to and discussing various topics. I brought up the Fukushima accident which happened almost one year ago. Around this time last year, I was in the process of finishing my Master’s thesis, preparing for the defense. I still remember, soon after accepting the offer from the RI, I was almost glued to the computer screen for every piece of news about Fukushima, from the first explosion, to the next one. Then I found out Switzerland politicians were considering a phase-out of nuclear. That did not deter me from coming here. However, I have to admit that, since my arrival, several research staffs already left and in comparison, there is fewer people coming to replace those positions. I reported my feeling of uncertainties to the Chair and we shared further opinions of how we evaluated Fukushima in terms of our future career prospects.

This led to another topic that I was interested in hearing the opinion from the meeting participants. As Switzerland, Germany are phasing out nuclear, Japan is planning to reduce dependence on nuclear power, we cannot ignore the more and more political support and activities in countries such as Iran, China, UAE, Turkey [WNA] . I have concerns that while nuclear energy is considered to provide energy independence for countries which obviously need it, they might not actually have enough of trained nuclear engineers, scientists, and advanced technological capabilities to accomplish the complex tasks of constructing and running, maintaining nuclear power plants.

Let’s be honest, will skilled engineers be willing to relocate from Switzerland or Germany to Iran, China, Vietnam, Jordan for more abundant jobs after their own countries decided to shut down their reactors?  If not, where will those nuclear-growing countries get the  expertise? They could of course develop themselves or buy from others (which seems to be the only commercial activities left for nuclear engineers in German). Well, take China for example. It buys and builds all types of NPP and from them, it tries to learn of the technological know-how. However, from every Chinese nuclear engineer I met, I was told that the nuclear activities in China are disorganized and the actual knowledge of nuclear power is immature. That’s the situation in the most “promising” nuclear-thirsty nation in the world. Not an assuring thought, is it? And don’t let me start on the situation in Iran!

I guess what I’m really worried is that, the safety of nuclear technology may not be adequately secured in countries that are (too) fast developing. On the other hand, the number of competent nuclear engineers are going to be smaller and smaller in countries that have a long history of nuclear presence after the decision of phase-out. Switzerland, Germany should have stayed unswayed and showed to the world that their nuclear power plants are safe and they have the competent nuclear engineers to make them safer.

Risky situations

April 9th 2010 was Apollo 13’s 40th anniversary (4 + 9 =13!!!)  I have seen the movie about this famous but unsuccessful lunar mission.  One memorable scene in the movie is when a team of engineers on the ground (maybe with some scientists) had to construct a device (historic image) out of materials available and accessible on the spacecraft from scratch. Otherwise the trapped astronauts would die from CO2 poisoning. I felt that particular scene truly portraits the problem solving skills of engineers.

When we are commemorating the safe-return of Apollo 13 and its crew, we reflect on the failures of the mission as well. The unexpected ignition of the hydrogen-oxygen mixture due to unexpected exposed electrical wires, leading to the loss of oxygen supply in the service module, consequently the shut-down of the command module, forced the abortion of the 4.4 billion mission as well as jeopardizing the lives of three crew members.

Even though a potential disastrous event was prevented at the end of the day, what kind of lessons we can learn from it? Perhaps the first thought is:  Expected the unexpected.

What that means is that, in order to prevent a grand failure, all possible routes leading to it must be considered and there must exist solutions and procedures (aka. backup plans) to ensure the failing of failure. In my opinion, crew member fatality would have been the grand failure, while others can choose their own definition of failures.

However, this approach is almost like an exhaustive search. If the “Butterfly Effect is also included, maybe that would give us the safest mission – which is taking forever to analyze all the possibilities of failures and the shuttle never gets to be launched!

Luckily, there already exist formal (and more practical) methods which determine the degree of safety and reliability long before Apollo 13 in 1970.  The idea came during World War II [1]. I’m guessing it was a major concern that the possibility of losing missiles before hitting the target or hitting the wrong target. Then the reliability and safety assessment method was extended to industries such as aircraft, space mission and nuclear reactors.

If we consider the exhaustive search above as infinite (and a continuous function f(x)) in the extreme case, by assigning weights (ie. probabilities) to the cases (value of f(x’)) that rarely occur (thanks to quality assurance) such that under certain weights, those cases are no longer worth considering. The weight values are basically probabilities of failures, which can come from statistical analysis of tests.  In simple terms, a reliable car, for example, implies it malfunctions less often than a less reliable car.

But probability/reliability alone cannot be the final indication of the degree of safety – just look at how unlikely (or even unanticipated) the ignition of oxygen-hydrogen tank was!  But it still led to the failure of the mission!

What we also need, is knowing the degree of consequences (the bad ones) associated with the probabilities! As I mentioned before, the direct consequence of the ignition was the loss of  oxygen supply in the service module. This loss itself is not the grand failure (fatality), but it is severe enough to result in an unsuccessful lunar mission. Therefore,  it is almost natural to express the combined effect of probability and consequence in a mathematical formula:

risk = frequency x consequence

where frequency can be calculated using the probability. A silly example to illustrate the equation above is that, suppose crew members got into a fight and there was fatality. This certainty would be a grand failure, hence represented by the largest (worst) consequence! But luckily the possibility (also, frequency) of such an event is absolutely zero (who would argue with that?), giving a zero risk scenario!

Now for  a more realistic example. A tragic airplane crash happened one day after Apollo 13’s 40th anniversary. Not only the Poland president and his wife were on board, but also the country’s top military, church elites were all killed in the crash. The consequence of the plane crash is more than the loss of  extraordinary lives. It also carries great social impacts in that the purpose of their visit to Russia was to commemorate a massacre that had divided Poland and Russia for decades.

If we apply our risk formula, the consequence of the plane crash is definitely the highest and the worst, while the frequency/probability of a plane crash is low but not close to zero. Unfortunately, had there been some risk assessment performed for this flight, it could have been easily determined that letting all Poland top officials and elites fly on the same plane is almost inappropriate. The weather condition and pilot’s misjudgment have been blamed for the accident. But I think it should be the organizers/planers of this flight who take the most responsibility.

Risk, reliability or safety assessment can be applied from multi-million-dollar space missions to a  couple hours of air travel. There are many risky situations in life too.  But before you decide to take the risk, remember to examine what the probability/frequency and consequences are!

[1] http://www.safetyassessment.com/

“Are nuclear reactors safe?”

Today I attended a workshop on networking skills, targeted to graduate level students and post-doc fellows. As a master student, who just started in last September, I felt like a freshman (f!rosh) again! I met many aspiring scientists and engineering students, but it struck me more when I was asked by one of the PhD students the question “are nuclear reactors safe”? (That was after we introduced ourselves and explained our areas of research)

Hmm….. why no one had asked about my opinion before?

I have to say that my experience with the nuclear industry is still very limited to an undergraduate course at University of Toronto, a 3-month summer internship at Chalk River with AECL, and three nuclear courses taken as part of my master degree at McMaster University.  So sometimes, I’d tell myself this:

I’m not doing crazy, dangerous or destructive science here because I’ve met so many intelligent nuclear scientists, engineers who are also parents, grandparents, friends, supervisors, etc. They are SANE people and I can trust that they know what they are doing, right?

Maybe I looked naive to that workshop participant who asked me the question (“Are nuclear reactors safe?”), because I was told once that I looked like 16 (2 years ago). He doesn’t know me other than my research field and he definitely knows little about nuclear energy!

But for people who (actually) know me, if I tell them “nuclear reactors are safe”, will they believe me without any doubts based on my character and education?

As a result of this simple question that I got today, I decided to open a blog, on which I will try my best to document and share my wonderful studies in nuclear engineering with people who know me or not. I can only gurrantee that the posts will represent my current personal opinions. I am not advocating that nuclear energy is the solution to Global Warming (for example). Neither am I trying to convince any of you to cast away your concern for the environment. After all,  I’m still learning about this controversial science and profession myself! But I am genuinely interested in how we (as a society) can utilize nuclear energy in the most constructive ways.