![]() Boosting development of the hydrogen economy through production from coal in the meantime is, in my book, not a terrible idea overall.Aisulu Aitbekova, left, and Matteo Cargnello in front of the reactor where Aitbekova performed much of the experiments for this project. It’s not there yet in terms of price or practicality, but it is certainly on its way. It can be made in a variety of ways through pure water splitting (including electrolysis, or through solar thermochemical and photoelectrochemical technologies, to name a few). I predict that hydrogen power will be zero-emission one day. However, depending on the end-use of the hydrogen, and subsequent transport processes, you might be better off in terms of energy output, or efficiency (and therefore carbon emissions), just straight-up burning the coal to make electricity.īut by using gasification of coal to make hydrogen, we can start building much-needed infrastructure and developing consumer markets (that is, hydrogen fuel cell vehicles) for a truly clean future fuel. Gasification processes that use hydrogen fuel cells on site can substantially increase their efficiency compared with traditional coal-fired power. How protons can power our future energy needs Road transport currently emits dangerous levels of pollutants in our cities every day. This is not possible on a small scale, such as hanging off the back of your car. Particulates, and potentially carbon dioxide, can be removed from the gas stream very efficiently. Producing hydrogen from coal in a large, central facility means pollution control can be put in place. This makes it a zero-emission clean fuel, at least at the point of use. When hydrogen is used as a fuel, it releases only water as a byproduct. Carbon dioxide is emitted through the combustion and thermal decomposition reactions, and is also a product of the reaction between carbon monoxide and water to make hydrogen and carbon dioxide. Hydrogen produced in this way is not a zero-emission fuel. Plus there is a small boost from the hydrogen that is already present in the coal. ![]() The main reason is that, because of the high oxygen content of this type of coal, it is less chemically stable and therefore easier to break apart during the gasification reaction. The hydrogen can then be run through an on-site fuel cell to generate high-efficiency electricity, although the plan at Loy Yang A is to pressurise the hydrogen and ship it off to Japan for their Olympic showcase.īrown coals are generally preferred for gasification over black coals for several reasons, which makes the brown coal of Victoria’s Latrobe Valley a good prospect for this process. No hydrogen yet.Ĭarbon monoxide in the gas stream is now further reacted with steam, generating hydrogen and carbon dioxide. The partial oxidation also makes its own gasification agent, carbon dioxide.Ĭarbon dioxide reacts with the rest of the carbon in the coal to form carbon monoxide (this is the endothermic gasification reaction, which needs heat input). Not enough is added, though, to completely burn the coal – only enough to make some heat for the gasification reaction. To produce hydrogen from coal, the process begins with partial oxidation, which means some air is added to the coal, which generates carbon dioxide gas through traditional combustion. Now we know the key concepts, let’s start again at the start. Because the resulting gas is not fully oxidised, that means it can itself be burned as a fuel. Quite the opposite, in fact – it needs heat input to progress. Gasification is endothermic, which means it doesn’t produce heat. Instead, the coal is reacted with a compound called a gasification agent. In gasification, however, the coal is not completely oxidised. ![]() Carbon dioxide itself cannot be further oxidised, and thus is the non-combustible end product of the burning process. Combustion, or burning, is the complete oxidation of a fuel such as coal, a process that produces heat and carbon dioxide. We can understand gasification by first understanding combustion. Over time, the oxygen and some hydrogen are gradually removed, leaving more and more carbon behind.īrown coal thus contains slightly more hydrogen than black coal, although the biggest difference between the two is in their carbon and oxygen contents. You can think of coal’s formation process as a progression from biomass (newly dead plant matter) to charcoal (almost pure carbon).
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