Can Electricity Really be Produced from Sulphur?  

Consider the following list: hydroelectric dam; nuclear power station; coal; fields of windmills, and sulphur. You are probably thinking that it is a list of methods used to produce electricity and that sulphur does not belong on the list. Well, you are mistaken, and Dr. Peter Clark will make you see things differently by maintaining that sulphur can now be considered as a source for electricity production. This renowned professor of chemistry at the University of Calgary will even go so far as to say that by using sulphur energy, it would be possible to supply 25 % of the electricity required in the entire province of Alberta.

Dr. Clark, who is Director of Research at Alberta Sulphur Research Ltd. (ASR), has recently revealed the results of his research. He shows that sulphur can be used as a source of fuel to produce enough energy in the form of water vapour to feed turbines that would produce electricity. Let’s take a closer look at the process and the chemical reactions that make this project possible. 

Alberta’s subsurface contains a number of primary resources such as coal, petroleum, tar sands and natural gases. The natural gases include sweet gas reserves containing methane (CH₄) (commercial gas) for the most part, and sour gas reserves containing carbon dioxide (CO₂), hydrogen sulphide (H₂S), and methane (CH₄). Sour gases are usually processed to recover the methane, the CO₂ escapes into the air, while the H₂S is made to react to obtain pure sulphur S₈ that is stored in huge outdoor containers. What Dr. Clark is proposing, and what has already been proven in the laboratory, is that the reservoirs of sour gas can be used more profitably. As usual, the methane is first removed, but the H₂S and CO₂ are retained. These two gases are subsequently brought into a pressurized chamber where they are burned. The products stemming from this combustion are sulphur dioxide (SO₂), water vapour and the remainder of the CO₂. The energy released from this reaction in the form of water vapour is so powerful that it will be able to make turbines turn to produce electricity. By way of comparison, coal combustion (the primary source of electricity in Alberta) produces 8000 BTU/pound, whereas hydrogen sulphide combustion produces 6000 BTU/lb. But that is not all! The resulting CO₂ and SO₂ will be redirected to the sour gas reservoirs. At that point, the following reaction will take place:

SO_2(g) + 2 H₂S_(g)       S₈₍₁₎ + 2 H₂O(g)

This means that the SO₂, a highly polluting substance, is recovered in the form of sulphur, and the CO₂ is never released into the air but rather kept in internal circulation. In addition, the liquid sulphur thus formed can also be passed into a combustion chamber to form SO₂ while releasing energy of 4500 BTU/lb. Once the H₂S reserves are exhausted, the underground reservoir will contain only liquid sulphur, to which the sulpfursurplus from tar sands petroleum refineries can be added for safer storage.  

This sulphur reserve will represent very little risk for the environment compared with outside storage. In addition, this buried sulphur can be available for future generations. Currently, the sulphur is used primarily as a fertilizer, as well as in various synthetic products such as elastomers and others. However, production far exceeds the demand, and the accumulation has become a considerable problem.

In short, as well as supplying a considerable amount of energy and electrical potential, this new chemical technology is very ecological for it prevents the emission of polluting gases such as SO₂ and CO₂.

A number of additional chemical engineers and others will join Dr. Clark’s team, and with the help of industrial partnerships, they will shortly begin erection of a test plant to be used as a prototype for a first commercial plant in 2004.