FACULTY OF EXACT AND NATURAL SCIENCES
ENVIRONMENTAL PROBLEMS THAT COULD BECOME AN ALTERNATIVE SOURCE OF ENERGY
While traditional power systems based on technical progress provide many benefits, they have an extremely negative impact on the environment and have resulted in the current global climate change. The temperature will rise for the following decade, and though it might only be by 2 degrees it will cause drastic changes to natural processes on earth. Hence, the quest for non-traditional energy sources is extremely significant for the energy industry and the household sector.
Today renewable energy technologies including solar, wind, hydrogen, hydroelectric, biomass and bio-fuels are being introduced in many areas of human activity. Hydrogen energy is among the most important alternative energy sources, and could solve the most acute environmental problems in large cities such as air pollution.
“Searching for sources of raw materials and obtaining hydrogen or electricity from raw materials is a pressing task’’, said Dr. Tamaz Marsagishvili, Doctor of Physics and Mathematics and Head of the Theoretical Studies Laboratory at TSU’s R. Agladze Institute of Inorganic Chemistry and Electrochemistry.
Working on renewable energy is the laboratory’s number one priority at this time. The essential precondition of turning to hydrogen energy is the creation of reliable, economical and ecological fuel elements that function on hydrogen or hydrogen-containing raw materials. Among these, hydrogen sulphide is significant. The Black Sea is at the centre of the researchers’ attention because its deep waters contain large amounts of hydrogen sulphide, hydrosulphide and sulphide ions (roughly estimated amount: 4.6-80 billion tons).Their sources are gas emissions from seabed volcanoes and geological cracks, organic substances washed down by rivers and decayed micro-organisms.
Extracting and using the beneficial components from the sea waters and seabed (e.g. H2S, K+, Mn, NH4+, CH4, etc.) are essential for dealing with ecological problems of the sea ecosystem, to decrease greenhouse gas emissions, and for obtaining renewable and non-traditional energy sources. This is why tackling the severe environmental problems of the Black Sea is an urgent task. The Black Sea not only poses a serious ecological threat but it could become a potential source of hydrogen energy. Studies show estimates of obtaining a potential of 100 billion kilowatt hours of electricity every year by processing hydrogen sulphide. Hydrogen sulphide can be used for fuel and energy, petrochemical synthesis and producing mineral fertilizers. Thus decreasing hydrogen sulphide in the Black Sea deep waters and oceans will mean reversing serious ecological risks naturally while providing clean energy sources.
Renewable energy ensures safe and continuing supplies with only moderate price fluctuations. Such sources of energy reduce air pollution and entail less reliance on natural gas. By promoting socio-economic well-being in developed countries and providing electricity for developing countries, it is easy to see why projects focused on these resources are being encouraged today. One such international grant project, BS-ERA.NET (Networking on Science and Technology in the Black Sea Region) entitled “Obtaining hydrogen from the Black Sea through using sulphide fuel elements” is a good example. The Theoretical Studies Laboratory research team includes T. Marsagishvili, G. Tatishvili, N. Ananiashvili, M. Machavariani, M. Kikabidze, J. Metreveli, E. Tskhakaia and R. Khositashvili, who are working with foreign partners from Romania and Bulgaria.
Many processes (adsorption, absorption, the Claus process, etc) have been developed to obtain hydrogen sulphide, however processing is too costly. Due to the low commercial value of the end product it is necessary to develop more economical and ecological methods to obtain it. This is essential for extracting hydrogen from hydrogen-sulphide in fuel elements. Over the last decade, there has been an increased demand for fuel from hydrogen sulphate, yet the current method of hydrogen sulphate extraction makes the process significantly complicated and costly.
Much research has been devoted to various options for obtaining hydrogen sulphate, but all of them include corroding gaseous hydrogen sulphate with costly catalysers and composed materials at high temperatures (800-1000C0), which is not commercially viable. However, the Black Sea has H2S dissolved in water. Although there are no published scientific results suggesting that fuel elements can be generated from hydrogen sulphate dissolved in water, the aim of the research is to create a type of fuel element that can be generated from the these raw materials.
One of the most noteworthy benefits of this product is that it does not have any negative impact on the environment. Obtaining hydrogen sulphate does not affect the sea in any way; it does not alter its salinity, acidity or Ph balance – and does not create waste. Thus the research being carried out is vital from scientific, technological and innovative points of view as well as for economic, ecological and social purposes.
Within the framework of the project, in order to provide more hydrogen sulphate in the sea, the researchers are considering possibilities for capturing sulphide-ion by natural and modified zeolites and synthetic cations. It has been proven that these materials are characterized by a high adsorption capacity, so they could be used as hydrogen sulphide adsorbents from natural sulphur waters. The team has studied non-adiabatic ion exchange processes in zeolite channels, and have made constant velocity calculations for the ion exchange process in porous channels during which one adsorbent particle is replaced by another. Analytic expressions for the characteristic parameters include environment reorganization energy, transition probabilities, and the speed constant of the processes. The project implementers also succeeded in creating a fuel element laboratory and large-scale laboratory models. As a result of the experimental research, they chose a non-expensive electrode material that is resistant to hydrogen sulphide and its corrosion, which – in addition to having the purpose of an electrode purpose, acts as a catalyst – and an ionic membrane, which has been determined to produce energy-generating properties from hydrogen sulphide during catalytic corrosion with sulphide oxygen in a fuel element. The end product can be used to produce carbon-free energy in the form of hydrogen.
With their Bulgarian and Romanian counterparts, the research team has confirmed their findings in the Black Sea deep waters. Studies carried on the research vessel, Academik, from the Institute of Oceanography of the Bulgarian Academy of Sciences, have led to the publication of several articles in Bulgaria. The aim of the expedition was to undertake large-scale laboratory experiments in real conditions and to determine how long the device can operate. Most importantly, the researchers obtained electromotive force (EMF) in the heat element from various depths of the Black Sea waters containing hydrogen sulphide.
A number of articles have appeared on these studies in local and international scientific publications, and significantly, the project implementers have succeeded in presenting a patent.