Activated carbon injection (ACI) has been an effective approach for reducing mercury emissions in various industries. The US power industry, for example, began implementation of ACI around 2014 with the onset of the Mercury Air Toxic Standards (MATS) which regulate the emissions of mercury and acid gases from coal-fired power plants. The lessons learnt from the power sector provide useful reading for the cement industry. By Erica Gonzaga, Carbonxt Group Ltd, USA.
As with any new environmental compliance regulation, the power industry’s focus for the first wave of powdered activated carbon (PAC) contracts was to achieve compliance. More recently, this focus has shifted towards optimisation and lowering overall costs. Several years of operational experience with ACI has now allowed plants to forecast PAC usage, understand seasonal spikes, assess plant balance impacts and determine the most cost-effective sorbent through long-term testing programmes.
