TY - JOUR AU - Garnham, B.L. AU - Langerman, K.E. PY - 2016/12/03 Y2 - 2024/03/28 TI - Mercury emissions from South Africa’s coal-fired power stations JF - Clean Air Journal JA - Clean Air J. VL - 26 IS - 2 SE - Research Article DO - 10.17159/2410-972X/2016/v26n2a8 UR - https://cleanairjournal.org.za/article/view/7004 SP - 14-20 AB - <p><em>Mercury is a persistent and toxic substance that can be bio-accumulated in the food chain. Natural and anthropogenic sources contribute&nbsp;to the mercury emitted in the atmosphere. Eskom’s coal-fired power stations in South Africa contributed just under 93% of the&nbsp;total electricity produced in 2015 (Eskom 2016). Trace amounts of mercury can be found in coal, mostly combined with sulphur, and&nbsp;can be released into the atmosphere upon combustion. Coal-fired electricity generation plants are the highest contributors to mercury&nbsp;emissions in South Africa. A major factor affecting the amount of mercury emitted into the atmosphere is the type and efficiency&nbsp;of emission abatement equipment at a power station. Eskom employs particulate emission control technology at all its coal-fired&nbsp;power stations, and new power stations will also have sulphur dioxide abatement technology. A co-beneficial reduction of mercury&nbsp;emissions exists as a result of emission control technology. The amount of mercury emitted from each of Eskom’s coal-fired power&nbsp;stations is calculated, based on the amount of coal burnt and the mercury content in the coal. Emission Reduction Factors (ERF’s)&nbsp;from two sources are taken into consideration to reflect the co-benefit received from the emission control technologies at the stations.&nbsp;Between 17 and 23 tons of mercury is calculated to have been emitted from Eskom’s coal-fired power stations in 2015. On completion&nbsp;of Eskom’s emission reduction plan, which includes fabric filter plant retrofits at two and a half stations and a flue gas desulphurisation&nbsp;retrofit at one power station, total mercury emissions from the fleet will potentially be reduced by 6-13% by 2026 relative to the&nbsp;baseline. Mercury emission reduction is perhaps currently not the most pressing air quality problem in South Africa. While the focus&nbsp;should then be on reducing emissions of other pollutants which have a greater impact on human health, mercury emission reduction&nbsp;can be achieved as a co-benefit of installing other emission abatement technologies. At the very least, more accurate calculations&nbsp;of mercury emissions per power station should be obtained by measuring the mercury content of more recent coal samples, and&nbsp;developing power station-specific ERF’s before mercury emission regulations are established or an investment into targeted mercury&nbsp;emission reduction technology is made.</em></p> ER -