This document provides information about computer modeling of electrostatic precipitators (ESPs). It begins with an introduction to ESPs, describing how they work to separate particles from gas streams. It then discusses different ESP types (dry and wet), installation, charging mechanisms, particle mobility, resistivity factors, and software used to model and control air pollution using ESPs. The document also includes C programming code examples for modeling parallel plate and cylindrical ESP designs.

1. COMPUTER APPLICATION OF
ELECTROSTATIC PRECIPITATOR
PRESENTED BY
VIKAS KUMAR VERMA
M . T E C H 1 ST Y R ( E N . N O - 1 1 5 1 9 0 1 6 )
ENVIRONMENTAL ENGINEERING
SUBMITTED TO
PROF. - U.B. CHITRANSHI
DEPARTMENT OF CIVIL ENGINEERING
INDIAN INSTITUTE OF TECHNOLOGY ROORKEE
11/10/2011

2. What is an Electrostatic Precipitator
 A device which separates particles from a gas stream by
passing the carrier
 gas between pairs of electrodes across which a
unidirectional, high-voltage
 potential is placed. The particles are charged before
passing through the
 field and migrate to an oppositely charged electrode.
These devices are
 very efficient collectors of small particles, and their use in
removing
 particles from power plant plumes and in other industrial
applications is
 widespread.
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3. INTRODUCTION
 Historically , the practice of collecting and treating waste
water is a relatively recent undertaking
 In India there was this inhuman practice of carrying solid
waste by a certain section section of society since time
immemorial which not only had a debilitating effect on their
health but also harmed the social fabric of our country.
 The first “modern” sewerage system for waste water collection
was built in Hamburg,Germany,in 1842 by Lindley.
 Since then a lot of improvements and innovations have been
applied to make the collection system more efficient and
useful.
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4. A Precipitator is a device that
captures particulates from a gas
stream
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7. Types of ESPs(Dry or Wet Electrostatic Precipitator)
 Dry electrostatic precipitator ( ESP ) devices are
employed on hot process exhausts (250 - 850 deg. F)
that operate above the dew point of the gas stream.
Dry electrostatic precipitator devices typically collect dry dust
particles such as wood ash, incinerator ash, or coal ash from
boiler or incinerator applications. Additional dry electrostatic
precipitator applications include carbon anode ovens, cement
kilns, and petroleum cat crackers. Dry electrostatic
precipitator devices are attractive due to their ability to collect
and transport the dust in a dry condition. This eliminates the
use of water and the concerns of pollution, corrosion and
dewatering efforts associated with scrubbers. If the dust
particles can be collected and handled in a dry condition it is
always more advantageous to employ a Dry ESP.
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8. Dry Electrostatic Precipitator
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9. Wet electrostatic precipitator ( ESP )
 This is old technology originally designed in the 1920's to collect sulfuric acid
mist using lead collection tubes. Today, ESP devices are employed on gas
streams that include oily and sticky particulates or gas streams that must be
cooled to saturation in order to condense aerosols that were formerly in the gas
phase. Due to the different characteristics of the collected precipitate, the
mechanical removal systems (rappers and vibrators) in Dry electrostatic
precipitator devices are not effective. Consequently, the Wet electrostatic
precipitator uses a water flushing system to remove the particles from the
collecting surface. The gas stream is either saturated before entering the
collection area or the collecting surface is continually wetted to prevent
agglomerations from forming. Some mist aerosols simply gravity flow down the
collecting surfaces. These devices are effective on acid mist, oil and tar based
condensed aerosols or applications where dry dust particles combine with
condensables to form paste like residues. Due to the wet environment of wet
electrostatic precipitator devices, they are typically fabricated out of corrosion
resistant materials such as stainless steel or special alloys.
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10. Wet Electrostatic Precipitator
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11. Installation of ESP
Insulator
Compartment
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12. How A Dry Electrostatic Precipitator Works
• Electrical migration
• Electrical mobility
• Corona discharge
• ESP theory
• Charging mechanisms
• Ash resistivity
• Flue gas conditioning
• Power consumption
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13. Electrical Migration
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17. Electrostatic Precipitator
Turbulent Flow with Lateral Mixing Model
1 2 3
1 2 3
(20) (12) (8)
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18. • Turbulent flow: uniformly mixing
• Perfect Collection
• The fraction of the particles removed in
unit time = the ratio of the area traveled
by drift velocity in unit time to the total
cross-section
 Deutsch-Anderson
Equation
dN 2 RVTE dt 2VTE dt
N R2 R
N (t ) 2VTE t
exp( )
N0 R
VTE Ac
1 P 1 exp Ac/Q: Specific Collection Area (SCA)
Q
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19. Charging Mechanism: Diffusion Charging
 Random collisions between
ions and particles
The total number of charges on a particle
d p kT d p ci e 2 N i t
n ln 1 (ci ~ 2.4 104 cm/s)
2e 2 2kT
Use esu, not SI units.
The total charges on a particle
q ne
Q: Does q depend on time?
Does q depend on dp?
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21. ELectrical Mobility vs dp
10 Diffusion charging
Field Charging
Combined Charging
Z (stC.s/g)
1
Typical fly ash
size distribution
0.1
0.01 0.1 1 10
dp (um)
Q: If the ESP is used to collect the
fly ash, how will the particle size
distribution at ESP outlet look like?
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22. Resistivity/Conductivity
 Impact of particles’ resistivity on ESP’s
performance: is desired
109 - 1010 ohm-cm
 Factors: temperature, composition
 Flue gas conditioning
Q: How does resistivity affect an ESP’s performance?
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23. Effects of sulfur content and temperature on resistivity
Q: Is S in coal good or bad? 11/10/2011

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25. Effective drift velocity as a function of resistivity by measurement
Use the same Deutsch-Anderson Equation with new we.
Q: Estimate the total collection area required for a 95% efficient fly-ash ESP
that treats 8000 m3/min. The ash resistivity is 1.6 1010 ohm-cm.
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26. Good for moderate
collection efficiency
(90% ~ 95%)
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27. High Efficiency ESP (>95%)
Q: In designing a high
efficiency ESP, a smaller
drift velocity is to be used.
Why?
Matts-Ohnfeldt Equation
k
AC
1 exp we
Q
Use k = 1 for fly ash
k = 0.5 or 0.6 for
industrial category
Rule of Thumb
• Below 95%, use Deutsch-Anderson Equation
• Above 99%, use Matts-Ohnfeldt Equation
• Between them, use an average
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28. Power Consumption
 Corona power
PC ICVavg
 Drift velocity
kPC
we
AC
 Efficiency vs. Corona Power
Power density ~ 1-2 W/ft2
kPC
1 exp
Q
k = 0.55 for Pc/Q in W/cfs up to 98.5%
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30. Computer Model Structure of ESP
INPUT DATA: Operator experience
METEROLOGY EMISSIONS RECEPTORS
Model does calculations
Model Output: Estimates of Concentrations
at Receptors
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31. Atmospheric
Chemistry
Emissions Numerical Pollutant
Inputs Routines Distributions
Meteorologic
Emissions al Fields Effects
Modeling
Visualization
Meteorologic
Inputs:
Population al Modeling
Economics
Roads Inputs:
Land Use Topography Controls
Industry Observed
Meteorology Meteorology
Solar
insolation
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32. Softwares using To Control Air Pollution By
ESP
ADAM
By US Environmental Protection Agency, Office of Air Quality
Planning and Standards (OAQPS). Air Force Dispersion Assessment
Model (ADAM) is a modified box and Gaussian dispersion model
AERMAP
By USEPA, Office of Air Quality Planning and Standards (OAQPS). A
terrain preprocessor for AERMOD. AERMAP processes commercially
available Digital Elevation Data and creates a file suitable for use
within an AERMOD control file
AERMOD Modeling System
By USEPA, Office of Air Quality Planning and Standards (OAQPS). A
steady-state plume model that incorporates air dispersion based on
planetary boundary layer turbulence structure and scaling
concepts, including treatment of both surface and elevated
sources, and both simple and complex terrain.
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33. AFTOX
By USEPAgency, Office of Air Quality Planning and Standards
(OAQPS). A Gaussian dispersion model that will handle
continuous or instantaneous liquid or gas elevated or surface
releases from point or area sources.
AP-42: Compilation of Air Pollutant Emission Factors (Mobile
Sources)
By USEPAgency of Mobile Sources. "Compilation of Air
Pollutant Emission Factors, Volume II: Mobile Sources"
(commonly referred to as "AP-42") has two sections, I -
Highway Vehicles and II - Nonroad Mobile Sources.
ASPEN
USEPAgency of Air Quality Planning and Standards (OAQPS).
The Assessment System for Population Exposure Nationwide
(ASPEN) consists of a dispersion and a mapping module.
BLP
By US E P Agency, Office of Air Quality Planning and Standards
(OAQPS). A Gaussian plume dispersion model designed to
handle unique modeling problems associated with aluminum
reduction plants, and other industrial sources where plume rise
and downwash effects from stationary line sources are
important.
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34. BlueSky
By US Department of Agriculture, Forest Service. A modeling
framework designed to predict cumulative impacts of smoke
from forest, agricultural, and range fires. The BlueSky smoke
modeling framework combines emissions, meteorology, and
dispersion models to generate predictions of smoke impacts
across the landscape.
CALINE4 (California LINE Source Dispersion Model)
By California Department of Transportation. A modeling
program to assess air quality impacts near transportation
facilities. It is based on the Gaussian diffusion equation and
employs a mixing zone concept to characterize pollutant
dispersion over the roadway
CAMEO
By US Environmental Protection Agency and National Oceanic
and Atmospheric Administration. CAMEO (Computer-Aided
Management of Emergency Operations) is a software suite of
applications that includes: CAMEO, ALOHA, and MARPLOT. It
supports government and industry chemical emergency
management with chemical safety and emergency response
data, digitized mapping, and air dispersion modeling.
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35. DEGADIS
By USEPA, Office of Air Quality Planning and Standards (OAQPS).
Simulates the atmospheric dispersion at ground-level of area source
dense gas (or aerosol) clouds released with zero momentum into the
atmospheric boundary layer over flat, level terrain. The model
describes the dispersion processes which accompany the ensuing
gravity-driven flow and entrainment of the gas into the boundary
layer.
Industrial Waste Air Model (IWAIR)
By USEPA, Office of Solid Waste. Evaluates inhalation risk and
estimates whether specific wastes and management practices may
pose an unacceptable risk to human health.
Internet Geographical Exposure Modeling System (IGEMS)
By USEPA, Office of Pollution Prevention and Toxics (OPPT). IGEMS
is a modernization of OPPT's older GEMS and PCGEMS tools. IGEMS
brings together in one system several EPA environmental fate and
transport models and some of the environmental data needed to run
them. IGEMS includes models and data for ambient air, surface
water, soil, and ground water, and makes the models much easier to
use than their stand-alone counterparts. IGEMS will have graphics
and (GIS) capabilities for displaying environmental modeling results.
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36. OBODM
Intended for use in evaluating the potential air quality impacts
of the open burning and detonation (OB/OD) of obsolete
munitions and solid propellants.
OZIPR
A one-dimensional photochemical box model that is an
alternative version of the OZIP model that deals with air toxic
pollutants.
PLUVUEII
A model used for estimating visual range reduction and
atmospheric discoloration caused by plumes resulting from the
emissions of particles, nitrogen oxides, and sulfur oxides from a
single source. The model predicts the
transport, dispersion, chemical reactions, optical effects and
surface deposition of point or area source emissions.
TSCREEN
Toxics Screening Model (TSCREEN) is a Gaussian model that
implements the procedures to correctly analyze toxic emissions
and their subsequent dispersion from one of many different
types of possible releases for superfund sites. It contains 3
models: SCREEN3, PUFF, and RVD (Relief Valve Discharge).
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37. C Programs of Parallel Plate ESP,Cylindrical ESP
//Design of parallel plate ESP , cylindrical ESP//
#include<stdio.h>
#include<math.h>
#include<conio.h>
#define permi 8.85*pow(10,-12)
#define u 0.000018
void cylin (double vt1);
void main ()
{
int i;
float size ,field, con;
double vt, vt1;
clrscr ();
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38. // Calculation of Drift Velocity //
printf(“Enter the size of the particle in mn”);
scanf(“%f”,&size);
printf(“Enter the field strength in KV/mn”);
scanf(“%f”,&field);
field = field*1000;
con=0.75;
printf(“Permi %e”, permi);
vt=(size*permi*field*con);
vt1=(vt/u);
printf(“nThe drift velocity is %e m/s n”,vt1);
printf(“ESP CALCULATIONn”);
printf(“1. Parallel plate ESPn”);
printf(“2. Cylindrical ESPn”);
printf(“Enter your choicen”);
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39. scanf(“%d”, &i);
if(i==1)
parallel (vt1);
else if (i==2)
cylin(vt1);
else
exit ();
}
void parallel (double vt1)
{
float eff, rate, len, hgt, space, area, number;
float volume, A;
printf(“Enter the flue gas rate in cu.m/sn”);
scanf(“%f”, & rate);
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40. printf(“Enter the percent efficiency n”);
scanf(“%f”, &eff);
eff=eff/100;
printf(“Enter the length of plate in m n”);
scanf(“%f”, &len);
printf(“Enter the height of plate in m n”);
scanf(“%f” &hgt);
printf(“Enter the spacing of plate in m n”);
scanf(“%f”, &space);
A=(-rate/vt1);
area=len*hgt*space;
number=A/area;
printf(“The number of plates required is %fn”,number);
volume=number*len*space;
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41. printf(“The volume of the ESP in %f cu.mn”,volume);
getch();
}
void cylin(double vt1)
{
float len, dia, eff, A, number, area, rate;
printf(“Enter the present efficiency n”);
scanf(“%f”, &eff);
eff=eff/100;
printf(“Enter the length of plate in m n”);
scanf(“%f”, &len);
printf(“Enter the dia of plate in m n”);
scanf(“%f”, &dia);
A=(-rate/vt1);
area=len*dia*3.14;
number=A/area;
printf(The number of plates required is %fn”, number);
getch ();
}
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42. CONCLUSION
 Seeing the emerging pollution along with increasing power demands in
India, Government of India has decided to set up nuclear power plants in
India.Thus, installations of ESPs( Electro-Static-Precipitators) has been made a
compulsion for the manufacturers of power plant boilers and equipments.
 ESPs all over India, catering to a variety of customer needs and providing cost
effective solution for oil mist and dry smoke problems on various metalworking
(metal-cutting & metal-forming) and heat treatment processes / applications
 An Electrostatic Precipiptator applies separation forces directly to the particles to
be collected. This is much more efficient than trying to apply separation force to
the entire gas stream, as is the case for venturi scrubbers or bag houses. The
substantial savings in operating cost can pay for the equipment in only 2-3 years.
The precipitator can operate at temperatures up to 750 deg. F providing durable
advantages over fabric filters.
 In INDIA 99% of the Power Plant using ESPs. So its widely used process for dust
removal having 99.99% efficiency.
 Now-a-days we collecting only Dry Fly Ash it used in cement making it maintain
same quality of cement.
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43. Thank You !!!
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