Program Item Details
TITLE: Dr. Peter Clark, Professor of Chemistry, University of Calgary, and Director and CEO, Alberta Sulphur Research Ltd.
SUBJECT: #11 Using Sulphur to Make Electricity
SYNOPSIS: Sulphur is a byproduct of oil and gas production. Mountains of sulphur are stockpiled in Alberta and markets are already diminished because of a global glut of the yellow powder. Expansion of the oilsands will produce even more sulphur. What are we going to do with the stuff?
One person looking at alternative uses for sulphur is Dr. Peter Clark of the University of Calgary. Preliminary research suggests sulphur could be used to generate electricity, supplying as much as 20 percent of Alberta's power needs. The process Peter is developing also involves the sequestering of carbon dioxide, a major climate change concern.
AUDIO: Download Audio (mp3 format)
TRANSCRIPT:
Intro: Dr. Peter Clark of the Alberta Sulphur Research Institute offers a two for one solution to a couple of problems facing the province. How to get rid of our huge stockpiles of sulphur and how to put more electricity on the grid.
As the crisis over the supply and rising cost of electricity grips Alberta and the rest of North America, people are desperate to get more power to the grid. Suddenly, solar power, wind power, even coal look pretty attractive. But has anyone ever thought of sulphur? That’s one thing Alberta has lots of. Sulphur is a byproduct of oil and gas production. And Dr. Peter Clark is researching new technology that would not only get rid of our mountains of sulphur, it would generate a tremendous amount of electricity. Peter teaches chemistry at the University of Calgary and he’s the Director of Alberta Sulphur Research Ltd.
Dr. Peter Clark
PC: Well the major interest is that when we produce natural gas there is usually hydrogen sulphide associated with the gas and, of course, since that’s a very poisonous compound, we can’t just emit that to the atmosphere. So a whole range of chemical processes really initiating in about 1955 have been invented and used in Alberta to try and, of course, mitigate the problems of dealing with H2S. In addition, the oilsands contain lots of sulphur which is there in a chemically combined form and too that has to be removed before we can then sell the oil products which we can derive from oilsands as an economic product.
CC: WELL WE CERTAINLY HAVE MORE SULPHUR THAN WE HAVE MARKETS, DON’T WE?
PC: That’s a major problem. Years ago sulphur was, in fact, in short supply but because of increased environmental awareness of emission of sulphur compounds to the atmosphere, we’ve produced more and more sulphur not just in Alberta but also throughout the world particularly in the Middle East, in France, in Germany, in China, in Russia, and therefore this sulphur has flooded the world market and, in fact, it’s displaced some Canadian sulphur such that we can no longer market it into the world market.
CC: WELL IN TERMS OF STOCKPILES, HOW MUCH ARE WE TALKING ABOUT?
PC: Well at the present time we have approximately fifteen million tonnes of elemental sulphur in storage. I’m sure some of your listeners have seen these huge yellow blocks around the province. These continue to grow at a rate of about two million tonnes per year. And we project into the future that, in fact, much, much more will go into storage. We calculate that up to a billion tonnes of sulphur will be produced in the next hundred years and this far exceeds anything that we’ve got in storage at the moment. The real problem is that the sulphur produced in the Middle East and also elsewhere will completely displace Canadian sulphur from the world market. And so if we don’t want to have that one billion tonnes sit there on the ground, then we have to come up with some alternate ways of using it.
CC: SINCE THERE’S SO MUCH EXPANSION OF THE OILSANDS RIGHT NOW, HOW MUCH OF A PROBLEM IS THIS GOING TO BE?
PC: Well the real problem for these plants is, in fact, sulphur production. One plant alone could produce enough sulphur in the next hundred years to cover about fifteen square kilometers of land area so this represents a very significant problem. This fifteen square kilometers of solid sulphur are described as just that which is associated with one plant. We envisage over the next hundred years perhaps another ten of these plants and so you can see that the problem will quickly magnify out of all proportion so we really do need to consider some alternate technologies to deal with sulphur from the oilsands developments.
CC: WELL THAT’S SOMETHING YOU’VE CERTAINLY BEEN LOOKING AT IS ALTERNATE WAYS OF USING THE SULPHUR AND ONE OF THOSE DEALS WITH PRODUCING ELECTRICITY. WHERE DOES THAT IDEA COME FROM?
PC: Well it originates from basic chemistry in that when we really examine all of our potential energy sources on earth, we find that there are only two types of materials you can burn to produce heat energy directly. Most people are familiar with carbon compounds such as methane and of course, oil products. The other compounds relate to sulphur compounds and in particular hydrogen sulphide and elemental sulphur. As yet these materials have never been used to really get energy. The major problem being is what to do with the SO2 emission has never really been studied in any detail so we’ve initiated some projects to try and examine how we might utilize that sulphur dioxide and at the same time get the energy from combustion of either sulphur or hydrogen sulphide.
CC: HOW FAR ALONG ARE YOU IN YOUR RESEARCH AT THIS POINT?
PC: Well, we’re not doing too badly. We’ve done a lot of work in the laboratory and we’re working with some companies in Calgary and also in Europe to take the technology into the field. Really we’ve established that the next thing that we need to do is to do a field trial so we’ve already got as much data as we need from our laboratory work. The next phase will be to construct a pilot plant and try and demonstrate the concept in the field.
CC: SO HOW WOULD YOU GO ABOUT THAT?
PC: Well the whole issue relates on combustion of either hydrogen sulphide or sulphur and then recompression of the waste gases back into a deep sour gas formation. Once the sulphur dioxide which originates from the combustion is in the formation, it will react with hydrogen sulphide which is there to produce sulphur and water in the formation. We know that this type of chemistry goes very well from our laboratory work but the key issue is to establish what happens in the formation. All of the chemistry points to really no real problem but, of course, we need to demonstrate that we can, in fact, inject SO2 into a reservoir. And so the next phase of the project will be to essentially combust some sulphur and then take that SO2 and inject it into the formation and study what happens in the reservoir itself.
CC: ARE THERE ANY ENVIRONMENTAL CONCERNS ASSOCIATED WITH THAT?
PC: Well there are always some concerns. We have to be careful how we handle sulphur dioxide. One of the key aspects of the project will be to liquify it and put it in lines and then compress it into the formation. So really the only environmental aspect that we need to be careful of is that we select the correct metallurgy such that we never have a rupture of one of these lines. Once the material is in the formation, because we will put the SO2 back down into the reservoir, then as I said earlier it will react with hydrogen sulphide and will form sulphur and water which will essentially remain in the reservoir and this should have no environmental impact since we know that there is already sulphur and water in these reservoirs. So that’s a very nice feature of the process.
In addition, we could have the added environmental benefit of taking any carbon dioxide that was originally produced with the sour gas and then reinject the carbon dioxide with the sulphur dioxide directly into the formation so we really have a means of getting rid of both SO2 and carbon dioxide and at the same time utilizing the energy of the combustion of the sulphur compounds to drive the whole process. This is somewhat different to standard reinjection technologies because there the energy of compression is obtained by burning methane or another fuel.
And so that direct combustion of the methane then, of course, produces more CO2 which is never captured. So this technology to utilize sulphur represents both a means of controlling CO2 emissions as well as getting the heat energy from either sulphur or hydrogen sulphide.
CC: SO HOW DO YOU ACTUALLY TURN THAT INTO ELECTRICITY? PC: Well, when you burn sulphur in a furnace, it generates a great deal of heat and that heat is captured as high pressure steam and the steam is used to drive a turbine pretty much as was being done since really the beginning of the steam age. So that kind of technology is already known but, in fact, we could enhance the efficiency of this process considerably if we can develop the materials to operate a sulphur dioxide turbine. I won’t go into the ins and outs of the firm dynamics of this system but if indeed we could do that then the efficiency of power generation would exceed any system which yet exists. But, I think, we are some way away from generating a sulphur dioxide turbine.
CC: WHEN YOU LOOK AT THE OVERALL NEEDS FOR ELECTRICITY IN ALBERTA, HOW MUCH WOULD THIS CONTRIBUTE TOWARDS THAT?
PC: Well, at the present time Alberta produces about eight million tonnes per year of sulphur and we can calculate the heat content of that sulphur and we arrive at the conclusion that it would count for practically 20% of the energy requirement, the electricity requirement for the current needs within Alberta. So about 1/5 of the power that we utilize could be produced by burning sulphur and its compound H2S.
CC: HAVE YOU BEEN GETTING MUCH INTEREST IN THIS?
PC: Well a significant amount of interest from some of the major oil and gas companies. We’re working with one company in Calgary at the moment and they’ve chosen a reservoir in which to conduct a pilot plant. We’re doing some fine tuning in the laboratory and once we have all of those data, then the next step will be for them to make a decision as to whether or not to proceed with this. So there is a very significant interest and also we have interest from companies in the United Kingdom, also in the Netherlands, and in Saudi Arabia.
CC: WOULD IT BE POSSIBLE THEN TO USE UP ALL OF THE EXCESS SULPHUR GOING THROUGH THIS PROCESS?
PC: We believe it would be. We’re in the position at the moment where we can sell perhaps six million tonnes of the eight million tonnes that we produce each year but year by year we sell less and less but we do calculate that we have the type of reservoirs that we need which could, in fact, get rid of all of the sulphur produced in Alberta.
CC: THANK YOU VERY MUCH
PC: You’re welcome
Dr. Peter Clark is a professor in the Chemistry Department at the University of Calgary and he’s the Director of Alberta Sulphur Research Ltd.