When dealing with mercury emissions there is often no requirement for a dedicated mercury removal system although several choices are available. The potential for controlling mercury emissions is largely dependent on the fraction of oxidised mercury in the flue gas. Within the boiler and certain parts of the AQCS train, mercury can undergo transformation from its elemental form to an oxidised or particle-bound form. Mercury oxidisation and subsequent capture are therefore reliant on the types of NOx, SOx and particulate removal technologies in use. Because mercury control is dependent on many factors, each circumstance must be considered individually and a thorough understanding is required of all aspects of the flue gas stream, from the fuel fired through to the stack. Boiler design experience is a must.

In cases where insufficient mercury capture is likely to be achieved by the AQCS equipment installed to control other emissions, there are proven technologies available to further reduce mercury emissions. At Doosan Babcock we are thoroughly familiar with all these issues and can select from a number of techniques that have the capability of capturing much of the remaining mercury. Our emissions reduction specialists work closely with our customers to help them meet their mercury emissions targets.