IECM 12.0 beta User Manual > Modules Included with the IECM > Pulverized Coal (PC) Plant > SET PARAMETERS > Mercury >

Carbon Injection

Inputs for activated carbon and water injected into the flue gas are entered on the Carbon Injection parameter screen. Water can be optionally added to reduce the flue gas temperature and enhance the effect of the carbon on removing mercury. Note that the actual removal of the carbon and mercury are accomplished in particulate and flue gas desulfurization control technologies downstream.

The following parameters are available:

•Activated Carbon Injection: Injection of water to reduce the flue gas temperature and activated carbon to enhance mercury removal are the only control technologies presently incorporated into the IECM.

•Carbon Injection Rate: The flue gas temperature, the mercury removal efficiency in the particulate device, the coal rank, and the mercury removal efficiency without control, determines the injection rate of activated carbon into the flue gas. Mercury removal due to the ash removed in a cold-side ESP or fabric filter in the absence of enhanced mercury control methods is specified in the input screen. The default value is most sensitive to the flue gas temperature and the mercury removal efficiency without control. Note that overriding the calculated value does not change the removal efficiencies on the previous screen.

•Carbon Injection Power Requirement: The power required for the water and carbon injection system is a function of carbon injection rate, the water injection rate, and the flue gas flow rate. This assumes the addition of a fan in the flue gas to balance the pressure drop. The default value is calculated as the ratio of the actual energy consumption by the gross electrical output of the power plant.