3. Smoke
⢠Smoke is a collection of airborne solid and liquid particulates and
gases emitted when a material undergoes combustion or pyrolysis.
⢠Smoke is an aerosol (or mist) of solid particles and liquid droplets that
are close to the ideal range of sizes for scattering of visible light.
⢠A smoke particle has a diameter of 1 - 10 microns
⢠It is commonly an unwanted by-product of fires.
⢠Smoke is also a component of internal combustion engine exhaust gas,
particularly diesel exhaust.
4. Composition
⢠The composition of smoke depends on the nature of the burning fuel
and the conditions of combustion.
⢠The naked eye detects particle sizes greater than 7 ¾m
(micrometres). Visible particles emitted from a fire are referred to as
smoke. Invisible particles are generally referred to as gas or fumes.
5. Composition
⢠Primarily it is composed of
⢠Nitrogen oxides
⢠Sulphur Dioxides
⢠Hydrogen Sulphide
⢠Carbon Dioxide
⢠Carbon Monoxide
⢠Hydrogen Cyanides
⢠Ammonia
⢠Aromatic components like benzene
6. Effects of smoke
Effect on Environment
⢠Smoke can damage the ability of plants to store food and water that also
damages the reproduction and plant growth.
⢠Smoke can create acid deposits in the form of acid rain. These acidic
deposits and acidic rain end up on soil and water that can hurt plants and
animals.
⢠It can cause water pollution.
⢠Heavy smoke can result in a smoke cloud that can reduce visibility by 70
percent.
7. Effects of smoke
Effect on Health
⢠It can cause breathing problems.
⢠It can be lethal for elder people and can increase the incidence of asthma in
children.
⢠Particles of toxic chemicals in smoke are easily inhaled through lungs and
can cause serious problems for health.
⢠Thus, heavy smoke results in a low production of vitamin D leading to cases
of rickets among people.
⢠It can cause severe eye problems, including burning of eyes.
8. Smoke meters
For measuring smoke density Smoke Meters are generally used.
⢠Smoke meters, also referred to as opacity meters, detect and measure
the amount of light blocked in smoke emitted by diesel engines from
cars, trucks, ships, buses, motorcycles, locomotives and large stacks
from industrial operations.
⢠The smoke meter readout displays the smoke density giving a measure
of the efficiency of combustion.
This makes the smoke meter an excellent diagnostic tool to ensure
proper maintenance of diesel engines for improved fuel economy and
protection of the environment.
9. Smoke density
⢠Smoke density is a term usually associated with opacity
measurements. The optical measurement relationships follow the
BeerâLambert exponential laws.
⢠The Bee-Lambert Law is usually expressed as
T=e-KL
where T is transmittance
K is the smoke density factor in units of inverse length
L is path length of the measured smoke sample column.
Conceptually , the smoke density terms represents the exponential light
loss sensitive per unit length of the smoke column.
10. Smoke density
⢠Smoke density in air is measured, like fog and smog, by having a
beam of light of known intensity a given distance away and measuring
how much light gets through. This can be done by having the light out
there or by having the light next to the measuring head and a retro-
reflector (one that returns a beam along its own path) out there.
11. How to measure Smoke Density?
In smoke density measurement generally following terms are used:-
⢠Smoke number is a term relating the output of smoke meters
(aethalometers) that measure optical properties of smoke on a filter
âpaperâ substrate.
A variety of smoke number scales have been developed to relate
different instrument measurements to the assumed amount of soot being
measured.
Common reporting scales include Hartridge Smoke Units (HSU), Bosch
Smoke Unit (BSU), Filter Smoke Number (FSN), etc.
12. Smoke Measurement
⢠Smoke measurement broadly classified into two groups:
1) Comparison Method
2) Obscuration Method
13. Comparison Method
Ringlemann Chart is used in this process. The chart shows five shades
of grey from pure white to an all-black section.
In use, the chart is set up at eye level line with the stack at such distance
that the sections appear to be different degrees of uniform grey shades.
Ringlemann number ranging from 0( no smoke) to No. 5(dense black
smoke).
16. Obscuration Method
Divided into 3 types
1. Light Extinction type-Intensity of light beam is reduced by smoke
which is a measure of smoke intensity. Ex. Hartridge smoke meter.
Photoelectric cell Light Source
Exhaust
Indicating Meter
Light Extinction type Onscuration method
17. 2. Continuous Filtering Type-Measurement of smoke intensity is
achieved by continuously passing exhaust gas through a moving
strip of filter paper and collecting particles. Ex. Van Brand Smoke
meter.
Filter tape roll
Exhaust
Filter Blocks
Filter Tape Drive
Obscuration Method (ContinuedâŚ)
18. Obscuration Method (ContinuedâŚ)
3. Spot Filtering Type-A smoke strain obtained by filtering a given
quantity of exhaust gas through a fixed filter paper is used for the
measurement of smoke intensity. Ex. Bosch Smoke meter.
Exhaust
Filter Tapes
Pump
19. Case Study-I
Great smog of Delhi
⢠Dated: 1 to 9 November, 2016
⢠Air Quality of Delhi and National Capital Territory between
⢠Air Pollution at this time peaked on both PM 2.5 and PM 10 levels.
This is reported as one of the worst levels of Air Quality in Delhi since
1999.
⢠Primary sources of smoke being those from the burning of crop
stubbles, lit garbage and road dust. This period also coincided with the
Indian festival Diwali, which is celebrated by firing firecrackers.
20. Great smog of Delhi
⢠Air quality can be measured by the amount of PM 2.5 and PM
10 particulates suspended in air.
⢠The reported Smog in Delhi
On Nov 7th, 2016 the PM 2.5 levels shot up to 999, while recommended
is 60 micrograms.
At the same time PM 10 shot to 999, instead of the recommended limit
of 100
⢠Visibility had reduced to about 200 meters around Nov 7th, 2016
though the temperature in New Delhi during that period was between
19 to 21 ÂşC
21. Effects of Great Smoke of Delhi
Delhi government declared a health advisory
⢠Breathlessness
⢠Chest constriction
⢠Irritation in eyes
⢠Asthma
⢠Allergy
22. Short-Terms effects
⢠The Chief Minister of Delhi at that time, Arvind Kejriwal came out
with the below proposed action items to attempt reduce the air
pollution
⢠All Delhi schools will remain shut for the next 3 days.
⢠For the next 5 days, no construction and demolition work will take
place in Delhi.
⢠All diesel generator sets have been banned for the next 10 days, except
at hospitals and in emergencies.
⢠The Delhi government will supply power to unauthorized colonies
which use diesel generators.
23. Short-Terms effects
⢠The coal-based Badarpur power plant will be shut down for 10 days.
There will be no fly ash transportation from the power plant.
⢠The Environment department will launch an app to monitor the
burning of leaves.
⢠Vacuum cleaning of roads will start from November 10.
⢠Water sprinkling will start on all roads from tomorrow.
⢠People should stay at home as much as they can and they should try
working from home.
⢠If need be, the odd-even traffic scheme+ will be brought back for a
short while.
24. Long term effects
⢠On November 25, 2016, the Supreme Court of India banned the sale
of firecrackers in Delhi to alleviate pollution.
⢠In another measure, the Badarpur power plant will remain shut at least
until January 31, 2017. This power plant is very old and polluting, and
even before the Great Smog, environmentalists had advocated for its
permanent shutdown.
25. Case study- II
⢠Great Smog of London
⢠A period of cold weather, combined with an anticyclone and windless
conditions, collected airborne pollutants â mostly arising from the use
of coal â to form a thick layer of smog over the city.
⢠It lasted from Friday, 5 December to Tuesday, 9 December 1952 and
then dispersed quickly when the weather changed.
⢠Government medical reports in the following weeks, however,
estimated that up until 8 December, 4,000 people had died as a direct
result of the smog and 100,000 more were made ill by the smog's
effects on the human respiratory tract. More recent research suggests
that the total number of fatalities was considerably greater, about
12,000.
26. Some other cases
⢠1930 Meuse Valley fog
⢠1939 St. Louis smog
⢠1948 Donora smog
⢠1966 New York City smog
⢠2013 Harbin smog
⢠2013 Shanghai smog