The use of natural gas reduced SO2
and particulate emissions in direct proportion
to the gas heat input. GR-LNB
had only a minor impact on the boiler.
Boiler efficiency decreased by about
1% during gas reburning because of
the increased moisture in the flue gas
View of low-NOx burners after installation.
resulting from natural gas combustion.
There was no measurable tube erosion,
and only small amounts of slagging
occurred. There was no reduction in
the efficiency of flyash collection at
the baghouse. After completion of the
GR-LNB project, the host site has continued
to operate the LNB system. The
gas reburn system has been retained
by the host utility but is not operated
at present because current NOx emissions
requirements can be met using
LNBs alone. Gas reburning can be used
in the future if needed to meet more
stringent regulations, although at somewhat
higher operating cost.