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TechDive9 Jul 2020
Flue Gas DesulphurisationWastewater TreatmentHKPC TechDive - Environmental Technology
9 Jul 2020
Billy CHEUNGSenior Consultant Green Living and Innovation DivisionHong Kong Productivity Council
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TechDive9 Jul 2020
Coal Energy is Cheap Reliable
Become a major power sources in many developing countries
Therefore,
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TechDive9 Jul 2020
Coal Fired Power Plant
Polluted Flue Gas
SO2
SO2
However…………
It produces polluted SO2 containing flue gas
which needs to install a flue gas Desulphurisation(FGD) plant to remove the pollutant SO2
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TechDive9 Jul 2020
Through the FGD plant, polluted flue gas is purified
SO2
SO2
But at the same time,Χ polluted FGD wastewater would
be generatedΧ FGD wastewater containing non
biodegradable nitrogenous compound, heavy metal, hardness, and others pollutants
FGD Wastewater
FGD Plant
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TechDive9 Jul 2020
Traditional wastewater treatment method is poor performance
Chemical Treatment
Biological Treatment
FGD wastewater
Hardness+
Heavy metal
Total Nitrogen
Poor Performance!
0
100
200
300
400
500
600
700
800
Day 0Day 1Day 2Day 3Day 4Day 5Day 6Day 7
Co
nce
ntr
atio
n o
f To
tal
Nit
roge
n (
mg
/L)
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TechDive9 Jul 2020
Chemical Precipitation
NS TreatmentBiological Treatment (Aerobic)
Biological Treatment
(Anoxic)
Biological Treatment (Aerobic)
FGD wastewater
Discharge/ Reuse
Hardness+
Heavy metalNS Compound Ammonia Nitrate + Nitrite Residual COD
NaOHSpecial chemicalAcid/Alkali Sugar
We adopt an innovative NS treatment method
The pollutant, total nitrogen content, is reduced and treated FGD wastewater meet the discharge level
Traditional Biological Treatment
Traditional Chemical Treatment
Our Innovative NS Treatment
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TechDive9 Jul 2020
CLP – Castle Peak Power Station
Pilot test has been performed in 2017
Detail design has been completed in 2019
Case Reference
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TechDive9 Jul 2020
Investigation of Change in Nitrogen Components along the Treatment Process
• Total nitrogen declines along the process
• Almost all NS components was removed after NS treatment process
Case Reference - Finding
0
200
400
600
800
1000
1200
T1 T5 T8 T10 T11 T12
Co
nce
ntr
atio
n o
f P
ollu
tan
ts (
mg/
L) Total Nitrogen
NS (Calculated)
Ammonia
Nitrate
Nitrite
ChemicalPrecipitation
NS Treatment
1st Aerobic Treatment
AnoxicTreatment
2nd AerobicTreatment
Change in Nitrogen Component along the
Treatment Process Determinant Raw Treated
Total Nitrogen 946 23.4