Power generation is the main source of air pollution in Hong
Kong and both the Hong Kong Electric Company Ltd. (HEC) and CLP
Power Hong Kong Ltd. (CLP) have been acting to reduce emissions.
One solution is to switch from coal to natural gas for
electricity generation. Natural gas combustion emits 90 per cent
less sulphur dioxide (SO2) and respirable suspended
particulates than coal, and 80 per cent less nitrogen oxides (NOx).
CLP introduced its first gas-fired generating unit in 1996 and
currently operates eight gas-fired units at the Black Point
Power Station. HEC commissioned its first gas-fired unit in
mid-2006 and will convert an existing oil-fired unit to gas
firing in 2008.
Another way to cut emissions is to use ultra low sulphur coal
and adopt control technology to reduce pollutants from burning
coal. Flue gas desulphurisation (FGD), for example, is an
effective means of reducing SO2. It acts by
"scrubbing" the flue gas with limestone slurry, which reacts
with the SO2 and removes it from emissions. Low NOx
burners modify the mix of air and fuel to retard conversion of
fuel-bound nitrogen to NOx and the formation of
thermal NOx. HEC will retrofit two more coal-fired
units with FGD and low NOx burners between 2009 and
2010. In addition to the retrofitting with FGD, CLP will also
install selective catalytic reduction systems, which further
reduce NOx, in its four coal-fired units between 2009
and 2011. |
 |
|
Gas-fired power plant at Lamma Power Station Extension. |
 |
|
Gas-fired power plant at Black Point. |
|
