Predicting Hg Removals with Activated Carbon Injection in Utility Gas Cleaning Systems

摘要

This paper validates the predicted Hg removals from NEA's MercuRator? package for cases in the Phase II NETL Hg field test database with activated carbon injection (ACI).Datasets from six full-scale sites characterized ACI with Darco Hg into one hot-side electrostatic precipitator/fabric filter (HESP+FF) combination (Toxecon?-I),four cold-side ESPs (CESPs),and one into the plate banks in a CESP (Toxecon?-II).The measured Hg removals varied from 7 to 95 %,yet the predictions were uniformly accurate to within the measurement uncertainty across the domain of test conditions,and depicted the test-to-test variations at all but one of the sites.Hg removals were predicted within 12.6 % (std.dev.),excluding the evaluation with the data from Conesville,which had large systematic discrepancies.MercuRator?'s satisfactory performance does not rest upon parameter adjustments.In fact,none of the parameters in the Hg/Cl in-flight reaction mechanism were changed from the values set in NEA's interpretation of the Phase I NETL database.Hence,MercuRator? should now be recognized as a truly comprehensive mechanistic framework for Hg transformations throughout the complete domain of utility gas cleaning conditions