carbon monoxide the silent killer

2. CARBON MONOXIDE
gas
tasteless
odorlesscolorless
Because it is impossible to see, taste or smell the
toxic fumes, CO can kill you before you are
aware it is in your home.

3. Effects of CO on plants
 No detrimental effects have been detected.
 Urban air : 50-60 ppm → no problem

4. Reduce
blood
capability
carry
o2
Effect

5. • No effects<10%
• Effect behavioral performance1-2%
• Central nervous system effects2-5
• Cardiac and pulmonary functional change.>5%
• Headachs,fatigue,death.10-80%
CoHb level% Demonstrated

6. Source COHb (%)
Endogenous (normal
heme catabolism)
0.4-0.7
Tobacco smokers:
1 pack per day 5-6
2-3 packs per day 7-9
Cigars Up to 20
Urban commuter 5
Methylene chloride (100
ppm for 8 hours)
3-5

7. Co
anthropogenic
natural

9. Indirect sources:
mud, bogs
►anaerob
conditions
►methane
formation from the
decay of organic
materials
The surface of oceans is
supersaturated in carbon
monoxide:
Algae and other biological
sources.
Decay of chlorophyll in the
soil

10. anthropogenic sources
0
20
40
60
80
100
120
1968 1970 1975 1977 1980
Emmission10^6tonne/y
y
Source from EPA
transportation
foul combustion
(power heating
industreal
solid wast disposal

12. Carbon monoxide is mainly produced as an
intermediary product of combustion
processes
in piston engines and boilers. The oxidation
of CO into CO2 requires a temperature of
minimum 990 K and a sufficient stationary
time into the combustion chamber. If the
combustion temperature is not high
enough or uniform inside the combustion
chamber,
when the exhaust gases are evacuated some
CO will not oxidize.
co o2 co2

14. Control of CO pollution
 Transportation is mainly responsible
Solutions:
 Perfect mixing of air and fuel. The maximum has been reached.
 Slow cooling of the exhaust gases. It is not possible
 Quick oxidation to CO2: catalytic transformation of carbon monoxide to
carbon dioxide
 Combustion of coal, oil, gas and biomass:
 The emission is restricted officially.
Emission limits for different fuels in Hungary [mg/Nm3]
Output range 140 kW-50 MW regulation number: 23/2001 KöM
Solid fuel Liquid fuel Gas fuel
Carbon monoxide 250 175 100

15. Catalytic Converter •
The main aim of
catalytic converter is to
convert the harmful
gases into the harmless
gases. • The catalytic
converter converts
harmful gases like
NOx, HC and CO into
compounds like N2, H2
and CO2. • Rhodium is
used as reducing
catalyst for converting
NOx in the exhaust has
into nitrogen and
oxygen. • Platinum and
Palladium are used as
oxidation catalyst
which changes HC and
CO into Water and
CO2.

17. Control of CO emission
Combustion devices, the CO depends on:
 Particle size of the fuel (greater the size, higher the CO
emission)
 Structure of the solid fuel (airy, loose structure eg. straw,
local oxygen deficiency in the bulk)
 Mixing of air and fuel (perfect mixing results in low CO
emission)
 Air excess ratio (lack of oxygen or low temperature and
residence time)
 Residence time at high temperature (longer residence
time at high temperature decreases the CO emission)

18. Control of CO emission: boilers
Thermal afterburner
Min. temp: 850 °C
Min. residence time: 2 sec
heat exchanger
flue gas with
high CO content
preheated
flue gas
afterburner
gas
burner

19. DETECTION
AND
ANALYSIS
methods
gravimetric
colorimetric
electrochemical
chemical

20. The quartz crystal microbalance (QCM) is the main source of inspiration
for gravimetric sensors
This sensor consists of a piezoelectric quartz plate, which is coated with a hygroscopic
material having resonance frequency in the MHz range, and it measures humidity due to
the change of frequency as shown in Figure
The change of frequency (Δf) can be calculated by the Sauerbrey Equation
Δf=−21Af02µρΔm where A represents the area of surface, μ is the shear modulus, f0 is the nominal frequency, ρ
is the density, Δm is the mass change due to absorption of moisture.
A general schematic of a gravimetric sensor based on frequency shift detection

21. Most are electrochemical
sensors with electrodes
(two or more) and
chemical mixture sealed in
a sensor housing.
The gases pass over the
sensor causing a chemical
reaction within the sensor.
Electrical charge is created
which causes a readout to
be displayed.

22. Flame ionization detector
 .
A flame ionization detector (FID) is a scientific
instrument that measures the concentration of organic
species in a gas stream. It is frequently used as a detector
in gas chromatography. Standalone FIDs can also be used in
applications such as landfill gas monitoring, fugitive
emissionsmonitoring and internal combustion
engine emissions measurement in stationary or portable
instruments.
The operation of the FID is based on the detection of ions
formed during combustion of organic compounds in
a hydrogen flame. The generation of these ions is
proportional to the concentration of organic species in the
sample gas stream