In support of the Government of the Hong Kong Special Administrative
Region (HKSARG)’s regional air quality improvement initiative, the Castle Peak
Power Company Limited (CAPCO), a joint venture between CLP Power Hong Kong
Limited (CLP Power) and Exxon Mobil Energy Limited (EMEL), proposes to install
additional emissions control facilities on their Castle Peak Power Station “B”
Units (CPB) to further reduce air emissions from the operations of these units.
CPB units use pulverised coal
as the primary fuel. All CPB units
were commissioned during 1986 to 1990 with a unit size of 677 MW (gross).
It is CAPCO’s
objective to responsibly manage the environmental impact of their operations and
to meet HKSARG's environmental license requirements
while providing reliable electricity supply. Since its full commissioning, CPB has
been retrofitted with low nitrogen oxide (NOx) burners for the boilers, flue gas
conditioning systems, and upgrades of the electrostatic precipitators (ESPs) in addition to boiler optimisation improvements in
recent years for improved particulates and NOx
control. As a result of these
measures and together with the introduction of natural gas in the mid 1990s and
increased utilisation of ultra low sulphur coal, emissions of NOx, sulphur dioxide (SO2) and particulates from all CAPCO
facilities have already been reduced by 77%, 44% and 70% respectively over the 1990
to 2005 period when the total electricity demand has grown by about 80%.
Based on the CPB emissions
control project description included in CAPCO and CLP Power’s 2005 Financial
Plan which was accepted by HKSAR Government, the following additional emissions
control facilities are currently proposed for implementation at CPB:
·
Selective
Catalytic Reduction (SCR) for NOx
reduction; and
·
Limestone
Flue Gas Desulphurisation (LS FGD) for SO2 reduction.
While there are several other emission control technologies available for
NOx reduction, final NOx
control facility will be subject to design optimisation. For the purpose of this Environmental
Impact Assessment (EIA) Study, SCR has been selected as the most conservative
process with respect to environmental impact. This is due to the fact that the SCR
system encompasses the facilities and elements associated with the other
available NOx reduction technologies.
These
facilities are expected to result in significant emission reductions of NOx
and SO2. Further reduction in particulate emissions is also
anticipated as a result of the LS FGD process.
1.2
Objective and Scope of
the EIA
As defined under Section 9 (4) of the Environmental Impact Assessment Ordinance (EIAO)(Cap 499), the above-mentioned Emissions Control Project (the
Project) is a material change to an exempted designated project (DP), the
Castle Peak Power Station (CPPS) [Category D (Energy Supply), Item D.1 (Public
Utility Electricity Power Plant) of Schedule 2, Part I], as a result of the
changes introduced by the SCR and the LS FGD operations to the types and
quantities of wastes, emissions and effluents. The Project also includes elements which
will qualify as DPs in their own right under Schedule 2 of the EIAO.
The main objective of this EIA Study is to provide a detailed assessment
of the nature and extent of potential environmental benefits and impacts
arising from the construction and operation of the Project in relation to the
issues specified in the EIA Study Brief (No. ESB 134/2005), including air
quality, noise, water quality, waste management, ecology, land contamination
and landscape and visual impacts.
The assessments in this EIA Study are conducted using well-proven and
internationally accepted methods based on the worst-case conditions associated
with the construction and operation of the Project.