AIR POLLUTION
INDUSTRIAL NOx REMOVAL
What is Air Pollution?
The Importance Of Air
 Other planets have sunlight, but the Earth is the only planet we know that
has air and water. Without air and water, the Earth would be unable to
sustain life.
 A diverse community of plant and animal life has thrived on this planet for
millions of years, sustained by the sun and supported by the soil, water and
air.
Definition Of Air Pollution
 Air pollution occurs when the air contains gases, dust, fumes or odour in
harmful amounts. That is, amounts which could be harmful to the health or
comfort of humans and animals or which could cause damage to plants and
materials.
 The substances that cause air pollution are called pollutants. Pollutants that
are pumped into our atmosphere and directly pollute the air are called
primary pollutants. Primary pollutant examples include carbon monoxide
from car exhausts and sulfur dioxide from the combustion of coal.
 Further pollution can arise if primary pollutants in the atmosphere
undergo chemical reactions. The resulting compounds are called secondary
pollutants. Photochemical smog is an example of this.
The NO molecule;
The NO molecule was first discovered by Joseph Priestley in 1772, the same person
who previously had discovered the oxygen molecule . Under atmospheric
conditions, NO appears as a clear, colourless gas. NO is present in the atmosphere as
a result of human activities such as the emission of waste gas from combustion
processes using fossil fuels, burning biomass, but also from natural sources like soil
emissions. NO plays an important role in the formation of photochemical smog
and acid rain.
NO is not only a dangerous pollutant, but it is also an essential molecule for living
species. NO is produced in nature by animal and plant cells from the amino acid, Larginine
In 1992, NO was named molecule of the year by the journal Science and
in 1998, the Nobel Prize in Medicine was awarded for the discovery of the effects of
NO in living organisms. Due to its small dimensions, the molecule is able to pass
through cell membranes and it can serve as a signalling agent .For example, in
mammals, NO helps to maintain blood pressure within certain limits by dilating blood
vessels and it plays a role in the regulation of the immune system. It also plays a role
in controlling the penile erection, by taking part in the enzymatic pathway responsible
for the relaxation of blood vessels.As a matter of fact,Viagra® amplifies the NO
effect in this process .Inside the brain, NO can contribute to the formation of
memory and it plays a role in the communication between neurones. Recently, it
has been discovered that NO is able to block a protein involved in Parkinson.s disease
providing new pathways for treatment methodologies.
NOx sources
Natural Sources - Lighting Bolts:
A natural source of nitrogen oxides occurs from a lightning stroke. The very
high temperature in the vicinity of a lightning bolt causes the gases oxygen and
nitrogen in the air to react to form nitric oxide.
N2 + O2 --> NO
The nitric oxide very quickly reacts with more oxygen to form nitrogen dioxide.
NO + O2 --> NO2
Both of the nitrogen compounds are known collectively as nitrogen oxides or NOx.
 Human Sources of Nitrogen Oxides:
At normal temperatures the oxygen and nitrogen gases do not react
together. In the presence of very high temperatures nitrogen and oxygen do react
together to form nitric oxide.
These conditions are found in the combustion of coal and oil at electric
power plants, and also during the combustion of gasoline in automobiles. Both
of these sources contribute about equally to the formation of nitrogen oxides.
In areas of high automobile traffic, such as in large cities, the amount of
nitrogen oxides emitted into the atmosphere can be quite significant. In the Los
Angeles area, the main source of acid rain is from automobiles.
In certain national parks such as Yosemite and Sequoia, automobile traffic is
banned to limit the amount of air pollution damage to the trees and plants. This also
has the effect of reducing the visual smog in the air.

WHY SHOULD WE CONTROL NOx?
NOx represent a family of seven
compounds.
Actually,
EPA
regulates only nitrogen dioxide
(NO2) as a surrogate for this
family of compounds because it
is the most prevalent form of
Nox in the atmosphere that is
generated by anthropogenic
(human) activities. NO2 is not
only an important air pollutant
by itself, but also reacts in the
atmosphere to form ozone
(O3) and acid rain. It is
important to note that the
ozone that we want to minimize
is tropospheric ozone; that is,
ozone in the ambient air that
we breathe. We are not talking
about stratospheric ozone in
the upper atmosphere that we
cannot breathe. Stratospheric
ozone protects us and the
troposphere
from
ionizing
radiation coming from the sun.
AQAST research highlights
NASA Aura Ozone Monitoring Instrument shows
decreasing NO2 between 2005 and 2010
by Bryan Duncan
1.
Yeniköy
2.
Yeni Kaptan
3.
İzmit-Anıtpark
4.
Köseköy
5.
Körfez-Tüpraş
6.
Körfez-İgsaş
7.
Körfez-Petkim
8.
Değirmendere
9.
Sopalı
10.
Yuvam
Removal Techniques
prevention of NOx formation during the combustion
process;
 removal of NOx in the flue gas (end-of-pipe)

1) Nitrogen Oxide Removal During Combustion
 Staged Combustion
 Fludized Bed Combustion
2) Nitrogen Oxide Removal After Combustion
 NOx prevention
 End of pipe NOx removal technologies: SCR and SNCR
 NO removal using micro-organisms
 NO removal using wet absorption with metal chelates
Staged Combustion
Fludized Bed Combustion
1) NOx Prevention
2) Schematic representation of the SCR process. NH3 liquid
is vaporized before being mixed with the flue gas
3) NO Removal Using Micro-Organisms
4) NO Removal Using Wet Absorption with
Metal Chelates
Çimento, Kireç veMagnezyum Oksit İmalat Sanayilerinde
Mevcut En İyi Teknikler Referans Dokümanı
Mayıs 2010
http://www.tcma.org.tr/images/file/IPPC.pdf
BEST AVAILABLE TECHNIQUES (BAT)
FOR NOx FOR EXISTING BASELOAD UK
COAL UNITS >300MW
http://www.environmentagency.gov.uk/static/documents/Business/UKTWG13_Final_NOx_baseload_coa
l.pdf
Improvement Options NOx
http://www.environmentagency.gov.uk/static/documents/Business/UKTWG13_Final_NOx_baseload
_coal.pdf
Limit değerler, değerlendirme ve uyarı eşikleri
The Emission Values of Solid Fuel
www.mevzuat.gov.tr
The Emission Values of Liquid Fuel
www.mevzuat.gov.tr
The Emission Values of Gas Fuel
www.mevzuat.gov.tr
EPA has established National Ambient Air Quality Standards (NAAQS) for NO2
and tropospheric ozone. The NAAQS define levels of air quality that are necessary,
with a reasonable margin of safety, to protect public health (primary standard) and
public welfare (secondary standard) from any known or anticipated adverse effects of
pollution. The primary and secondary standard for NO2 is 0.053 parts per million
(ppm) (100 micrograms per cubic meter), annual arithmetic mean concentration.
Tropospheric ozone has been and continues to be a significant air pollution
problem in the United States and is the primary constituent of smog. Large portions of
the country do not meet the ozone NAAQS and thereby expose large segments of
the population to unhealthy levels of ozone in the air. NO2 reacts in the presence of
air and ultraviolet light (UV) in sunlight to form ozone and nitric oxide (NO). The NO
then reacts with free radicals in the atmosphere, which are also created by the UV
acting on volatile organic compounds (VOC). The free radicals then recycle NO to
NO2. In this way, each molecule of NO can produce ozone multiple times.40 This will
continue until the VOC are reduced to short chains of carbon compounds that cease
to be photo reactive (a reaction caused by light). A VOC molecule can usually do this
about 5 times.
In addition to the NO2 and Ozone NAAQS concerns, NOx and sulfur oxides
(SOx) in the2 atmosphere are captured by moisture to form acid rain. Acid rain, along
with cloud and dry deposition, severely affects certain ecosystems and directly affects
some segments of our economy. All of these facts indicate an obvious need to reduce
NOx emissions. However, to successfully do so, we must understand the generation
and control of the NOx family of air pollutants.
The technique which SANTA uses
REFERENCES
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www.mevzuat.gov.tr/Metin.Aspx?MevzuatKod=7.5.14027&MevzuatIliski
=0&sourceXmlSearch=b%C3%BCy%C3%BCk%20yakma%20tesisleri
http://www.mevzuat.gov.tr/Metin.Aspx?MevzuatKod=7.5.12188&Mevzu
atIliski=0&sourceXmlSearch=hava kalitesi
http://www.santa.com.tr/YONERGE/NOx-emisyonu.pdf
http://www.epa.gov/ttncatc1/dir1/fnoxdoc.pdf
http://www.environmentagency.gov.uk/static/documents/Business/UKTWG13_Final_NOx_base
load_coal.pdf
http://www.environmentagency.gov.uk/static/documents/Business/UKTWG6_Final_NOx_midm
erit.pdf
http://www.tcma.org.tr/images/file/IPPC.pdf
http://web.deu.edu.tr/fmd/s18/18-08.pdf
http://www.oecd.org/environment/indicators-modellingoutlooks/31558547.pdf
Thanks for Listening
Zeynep AKTOSUN
21024334
Bağdat İlkay İLOĞLU
21024683