Download - Air Pollution Control: Chapter 1, Intro

8/13/2019 Air Pollution Control: Chapter 1, Intro

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n ~ c h

CO 'JVER 10'1 FACTORS '

1 rt o.lO.tX m = 12 tn - mile 52XO - nautical mllc/6076= km f.I2X I

1 111 2X I It 19.17 tn km 1000 - 100 em - 1000 mmn11cron . = 106 JW l - 1011 nm - 1010 A

I Ibm ~ \ i l ) J short tonf20 X l long ton/2240 = 16 01 (a v.)

Font:

Vulunu.:

.. t . q ~ y

14.5X ot (troy) metnc ton (tonnc)/2204 .6 3 = 7000 grain .>lug 12.2

1 kJ : 2 2046 lhm = I000 g (metric ton or tonne or Mg)/ I 000

1 lbf 4.44X2 N 12.2 Ibm It/'> = 12.2 po undal =0 .4536 J g lIN kg / - . = I O d y n kgf/9.X I 0 224H lbf

I ft 1 0.02X1 1 m 1 2 U l l i tcrs= 7 .4 X U.S. gallons6.2' Impe rial ga llo ns= acre ft / 4 3 560

I U.S. gallon 21 1 in .1 - barrel (petrolc um) / 4 2 = 4 U.S. qua rtsX U.S. pints 3.7X5 lit e rs - 0 .003785 m1

I m 1 1000 liter '>- 15.29 ft 1

I Blu 105'i J 1.055 J w s - 2.93 x I0 4 J wh = 252 cal9 ~ fl lbf - J.93 X \ () 4 hp h

I .J m W ., v o lt coulomb = 9 .4 H x 10 4 Btu- 0.239 cal 10- erg - 6.24 x 101H e lec tron vo lts

I e M ~ \,tluc' . u ~ mmtl) rounded rhc rc arc sC\c ra l dchnlli Oil \ fo r \omc of thc>c (jUantlli cs. e.g . theBtu .md the


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1 hp ~ ~ 0 It lbf/'> = :n lXXl t lbf/rmn 2)4 c Btu/h 0 ~ 4 h \\'I W J/'> m/-. = \Oit ampac I '4 x 10 1 hp 0 ~ ~ l l l < l l . >

9 49 x 10 Btu/ -.l1rt \ \Ur t :

I utm IOI.HPa 1.013 bar 14 .696lhf/in . \ \ X91t lll 11att:r29.92 rocheCO lity:

I C> 0.01 o k e 0.0 I cm' ; , 10 11 m'/-. I cp/( g nn 1l

l'emp erature:K

I OX x 10 ft1/ . cp/(CJ2.4 1hm/lt 1

C + 27115 = R I.Xr +4'i9.67 = I.X K

( oncentrutlon (ppm ):I X ( '

In the arr pollutron IHcraturc and 111 th \ b o o ~ ppm .tpplu.:tl to a : "' ,d\1-.t\..,mean' pan' per mrllron h} 1olumc or b) mol l'hc'>C arc ttkntK.d lor .m tdcal ga ...nd practit.ally tdcnl cal for mo'>t ga'e ' ol atr pollutrnn Hllcrc'>l at I atm prc .. ,urc.:Ppm apphed to a hqutd or \oltd mean' pan' per mtllwn ~ m,,,,

For perfec t ga\e'> at I atm and 2 i C I ppm (40 X7 molcctil.tr llctghl)1g/m1Common l nit


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IRPOLLUTIONONTROL

ENGINEERING~ t o m h inton


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oHr oto A catalytic converter for a small trucJ.., sec chapter 13. Those fixautos arc smaller. normally havi ng only one or two honeycomb catalyst u n i t ~ inplace of the three -.h1mn here. The )\ygen sensor is inse rted in the in let pipePhoto courtesy of I n111ctt n a on mental l ech Co.John J Mooney and Carl D. Keith ~ h r c d the 2002 National Medal of Technology awaad from the U.S. go crnmcnt for tiH.: ir deve lopment of th is type of catalys t \vhalc worJ..ang I.Jr l: ngclhard. I he mil lions of these de vices on autos andlluc have grca tl> 11nprovcd the air quality in the large c ities of thc United l e ~.tnatmg about 19XI and many other coun tries sinee then. Iryo u li ve in such a cityyour peNHllll hl. alth presumably imprO\ ed beca use o f th ese dev ices.


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IRPOLLUTIONONTROLENGINEERING

econd Edition

oel de eversniversity of tuh

WAVElAND

PRESS INC.Lon).l orovt. lllnlOI


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I IH tntormation abou t this book, co ntac t:\\u\ eland Press. Inc.41 XO II Route XJ. Sui te I 0 I1 011 (iroH:. 11 60047-95


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BOUTTH UTHOR

Noel de Never received a B . from Ianford U n i v e r ~ i t y in 1954. and M.S. andPh .D. degrees from the University of Michigan in 1956 and 1959 all in chemicalengineering .

Hew rked for the research arms of what is now called the Chevron Oil om pany from 1958 to 1963 in the areas of chemical proces:-. development. chemicaland refin ry pr cess design. and secondary recovery of petroleum. lit.: has been onthe faculty of the University of tah from 1963 to the present in the I cpartment ofChemical and uel s ngineering.

He has w rked for the National Reactor Testing , ite. Idaho ~ a i l s Idaho. onnucl ar pr blems; for the U. . Army I larry Diamond Laboratory. W a ~ h i n DC.on weap ns; and for the ffice of Air Programs of the . . . EPA in Durham. NC. onair polluti n.H was a ulbright student of hemi a l Engineering at the Technical Univer

~ i t y of Karlsruhe, West ermany. in 195 1955 ;a fulbrightlectureron Air Pollutionat the niver idad del Valle, in ali. Colombia, in the :-.ummer of 1974; and th enat the niver. idad de Ia Republica . Montevideo, ruguay. and at the Univer:-.idadaciona l Mar del Plata , Argentina , in autumn 1996.

lie was a member of the tah Air onservation 'ommi ttcc (t he state ' '. airpoll uti n ntr I b ard) fr m 1972 to 19R4 and its chair in 19 0 19H4 . lie 'oervedon the tah overnor's itiL.en Advisory Task Force on the Protection of Vi-,ibi1-6, the tah Legislature s Hat.ardous Waste a ~ k Force in 19HH the Utah

r's lean Air ommission in 19R9 1990. and the We stern Governor 's onrand anyon Visibility Transpo rt ommission iti;en\ Advisory Board,6.area of re earch and publication arc in nuid mechanic '., t h e r m o d y n a m i c ~ .

atr polluti n. techn logy and soci ty, energy and energy policy. and exp losions andhre


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i ABOlff TilE AUTHOR

In 993 he received the Corcoran Award from the Chemical EngineeringDivi ion of the American Society for Engineering Education for the best paper( 'Pr duct in the Way ' Processes ) that year in hemical Engineering Education

ln addition to hi erious work he has three de Nevers's Laws in theMurphy ' Law s compilation, and won the title Poet Laureate of Jell-0 Salad atthe La t Annual Jell-0 Salad Festival in Salt Lake City in 1983.


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2

ONTENTS

r face xviN tati n xv iiilntr du ti n to Air P llution ontrol11 me of the His tory of Air Pollution ontrol in th e nitedtales of America1 2 Wh y the uddcn Rise in Interest in 1969- 1970?I. Dirty Air Remova l or mi ss ion ont ro l?1.4 ne Problem or a amit y of Prob lem s?1.5 mi ss ions Transport,1.6 nits and tandards1.7 The Plan of This BookI. umm ary

ir llution Effec ts2. 1 ffec t of Air Pollution on I uman llea lth

2. 1.1 Animal Ex periments2. 1 2 hort-Term xpos ure of Iuman Volunt rs2. 1. Epidemiology2. 1.4 Reg ul ations to Pro tect Iuman ll ca lth2.2 Air Pollution Effec ts on Property2. Air P llution Effec ts on Vis ibi lity

2.4 umm ary

355791II

1313182 12 12627335

v


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viii NTENTSAir Pollution Control Laws and RegulationsAir Pollution Control Philosophies 403.1 U S. Air Pollutio n Laws and Regulations 403.2 Air Pollution Control Philosophies 423.3 The Fo ur Philo ophies 433.3.1 The Emi ss ion Standard Philosophy 433 3 .2 The Air Quality Standard Philosophy 493 3 3 Emi ss ion Tax Philosophy 523 3 4 Cos t-Be ne fit Philosophy 553.4 Marke t Contro l and Emi ssion Rights 58.5 Pri ncipal U. . Air Pollution Laws 593.6 um mary 60

4 Air Pollution Measurements, Emission Estimates 634.1 A Representative Sample 644.2 Ge ttin g the Re pres entative Sample to the Detector 684.3 once ntrati o n Determination 6H4.4 Ave rag ing 694 5 tand ard Ana ly ti ca l Methods 7 14.6 Determining Po llutant Flow Rates 724.7 lso kinetic Sampling 734.8 miss ion Fac to rs 744.9 Visible Emiss io ns 774.10 umm ary 7X

5 Meteorol ogy for Air Pollution Control Engineers 8]5.1 The Atm osphere ~5.2 Horizo ntal Atmosphe ri c Motion H5.2.1 Eq uatoria l Heating, Polar Cooling H5.2.2 Th e ffec t of the Earths Rotation H65.2 3 Th e Influence of the Ground and the Sea H95.3 Vertica l Mo ti o n in the Atmosphere 905 3 .1 Air De nsity hange with Temperature and Humidity 905.3 2 Ai r De nsity hange with Pressure 9 15 3 Atmosphe ri lability 955 3 .4 Mi xing He ight 1005 3 .5 M is ture 1025.4 Winds 1065 4 .1 Veloc ities 1065.4.2 Win d Direc ti on 1075.5 Temperature Inversions l5. umiga tions, tagnati ons 2.7 Meteo rological Forecas ts 45. umm ary 4


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404424343495255585960

63646868697 1727374777X

8]8388868990909 195100102106

106107l l

11 2(1 411 4

7

ir P llut nt oncentrati n Model 6.16.6.

6.4au sian Plume erivatio nme Modifi ation f the Baste tan Plume quuuon

6.5 Long-Tenn Average ses f aussiun Plume Mooeb6.6 P llutnnt rea tion and.7 Multiple ell Mod IRe ept r- riented and ur e- riented Air Pollution Model\ther T pi s6 I Building Wakes. .2 Aerodyn ami D wnwa h6.9.3 Transport Distances6 .4 Initial Dispersion6 5 EPA -Re ommended Models.10 ummary

r Idea in Air P lluti n ontrol7 I Alt ernatives

7.I. I Improve Dispers ion7. 1. 2 Redu e Emi ss ions by Process hangc, Po llut iO n Preve ntion7 I. Usc a Down stream P llution ontrol Device7.2 Re urce Recovery7. The Ultimate Fate f P llutants7.4 Designin g Air Pollution ntrol ys tcms and Eq uipment7.4 .1 Air Pollution ontro l quipmcnt os ts7.5 uid Yeloc itic in Air Pollution ontrol Equi pment7. Minimi zing Volumetric Flow Rate und r c ~ s Drop7.7 ffi iency, Penetration . Nin s7. H m ge ne us and Nonhomoge n Pollu tant \7. Ba ing al ulation s on lnen Flowratc\7.10 mbu Lion7 I 0.1 What Burn s?7.10.2 Hea t of ombusti on

7. 10.3 xplosive or ombustible imits7 I0.4 Equilibrium in ombustion Reac ti ons7.10 .5 ombusti n Kinetics. Burning Rate >7.10.6 Mixing in ombu s tion Reactions7.10.7 Flame Temperature7.10.8 ombu tion Time7.10.9 Th e Volume and ompos it ion of n Products7.11 hanging Volumetric I w Rates

I I I11912012612612I 7t-n14l14414614814914914915015015 1152

16016016016 i16616616716H16817017 117117517617717 l17 l17 lIH182ll318418819 1194


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X CONTENTS

7.12 Acid Dew Point7.13 Catalys ts for Air Pollution Control7. 14 Summary

8 The Nature of Particulate Pollutants

9

10

8.1 Primary and Secondary Particulates8.2 Sett ling Velocity and Drag Forces

8.2. 1 Stokes Law8.2.2 Particles Too Large for Stokes Law8.2.3 Par ticles Too Small for Stokes Law8.2.4 Stokes Stopping Distance8.2.5 Aerodynamic Particle Diameter8.2.6 Diffusion of Particles8.3 Particle Size Distribution Functions8.3. 1 A Very Simple Example: The Population of the United

States8.3.2 The Gaussian, or Normal, Distribution8.3.3 The Log-Normal Distribution8.3.4 Distributions by Weight and by Number

8.4 Behavior of Particles in the AtmosphereK.5 Summary

ontrol of Primary Particulates9.1 Wall o llec tion Devices

9 . I . I Gravity Settlers9. 1.2 e ntrifugal Separators9 . 1.3 Elec tros tatic Prec ipitators (ESP)92 Dividing o llec tion Devices9.2. 1 ur face Filters9 .2.2 Depth Filters9.2 .3 Fi lter Medi a9.2.4 Scrubbers for Particulate Control9 1 Choosing a o llector

l 4 Summary

ontrol of Volatile Organic Compounds (VOCs)I0.1 Vapor Pressure. Eq uilibrium Vapor Content Evapo t10 2 YO s ra1onI 0

104

Control by PreventionI0 .3. 1 Subst itutionIO.l .2 Process Modification10.3.3 Leakage ControlControl by Concentration and Recovery10.4. I Condensation

20920921621721922222)2 262 26227

24l)2.J


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l l

(horpuonb'orpuon ( \:ruhh111g J105 1dauon'ombu,uon (lnwJc:ratton 1

Bwloglcul Oxldiltton tHiohltr.l ton)106 The Mobtle ourc.:e Problem10 7 h -.1ng u ontrol T c : d 1 n o l o ~10 ummury

ntrol f ulfur i d e ~11.1 Elementury 0 1dntton Reduction Chenmtry ol SulfurttrogenII 2 cr 1ew of the Sullur ProolcrnII Th Rem val of Reduced Sulfur Compouml\ from Pcttokun1

and uturul Gu-. Stream'II I The \es and Lnuttatton' of Ab,orher' and Stnpperfor A1r Pollutton Control11 32 ulfur Removal from I lydnx:nroon'.4 Removul of 0 2 from Rtch Wa,tc Ga c

11 5 R m val of from Lean Wa,tc (J; c'11 5 1 orced Oxtdatton Llntc,tonc Wet Sc.:ruhhcr'11 52 thcr Approad1c'

11 6 It mauve to "Burn and Then Scn1b"11 6 1 hangc to .t Lower Sultu1 Content htcl11 62 Remove Sullur from thl h1cl11 6 Mod1fy the Comhu't1on I HX:C\\11 6 4 Don ' t Burn ut All

II 7 ummary

12 ntr I f Nitro en Oxides12 An vcrv1cw of the N1trogcn 0 1dc l'rohkn1

12 11 'ompun,onwlthSulfurO 1dc'1212 Rcactl\lll\ 111 the Atmo,phcrt1213 and N0 1 Fqutl1hnum121 4 Thcmlttl, Prompt. .tnd h1cl 0

122 Th rmal122 1 The Zcldov1d1 Ktnt'tl l of lhcrm .tl 0 h1r111.1tton1222 l lcating and Cooling f'11ne'

12J 012 412 5 on ombu,tton Source' of ltroj. Cil 0 tdc'12 ntrol of 1trogcn Oxtdc hnl\\1011'

12 I 1trogcn Ox1dc Control hv Comhu't1on M4-lX4 X

1.m

II> I41>241>4


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15.4 Indoor Air Pollution15.4.1 Indoor and Outdoor15 .4.2 Models15.4.3 Control of In door Air Quality15.5 The Radon Problem

15 .6 ummary

App ndixeU eful ValueA. l Value of the Uni versal Gas o n ~ t n tA.2 Vapor Pre sure Equations

B Table of AcronymsC Fuel

. I Where Fuels Come From How They Burn

.2 Natural Gas

.3 Liquid Petroleum Gas Propane and ButaneC.4 Liquid Fuels

.5 Solid Fuels.6 omparing Fuel Prices and m o

D Elementary Chemistry of Ozone ProductionE Ad orber Breakthrough TimeF An wers to Selected Prob lems

Index

CO I TIXTS x

54:254254454 755055 :

558558558558

560562562563564565566569

57 1574580582


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~ P ~ R ~ E m F A E

1ht ' b


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1'1111-.t I \ '

h all the.: prohh:m,, to >t:t: \\here more complc.:\ .mu complc.:tc1 tm nl\ re eith r d -.cnhc.:d or rekrrcd 10 In man; p act'' 111 the t>ooJ.. there arc1 re liOn not dir tl appllcahlc to atr pollutton and prohh:m' not d t r e ~ t l ; rdatcd

1 tr polluti n. m of thc.: c.: an: there hc.:cau c : the.:} >hll\\ lntc:re,llng r c : l < ~ t e t l t e c hnt al ues that do not appl dm:ctly to a1r pollutwn o t H m l luH:Iude tht >t t>c.:cau >cI thtnJ.. th y help stud nt-. hutld mental hndgc.:-. to other part\ olther (XT >OrHtl expc.:n o .The more the >ludent-. an: ahh: llllnl grate the ne11 111lonnatron 111 tim h o o ~iot 1 th tr i ~ t i n g knowledge ha >e hy >Uch o c t t o n the more IIJ..cl; the) .tre to

1 10 it und able to u' 11.I will be very grateful to reader' \\ho fXltnt out to me typo raph11. error,,10 rre 1equa tion numh r >, incorrect figure number,, or ' npl; error' ol any ~ t n dU herr rswillb Orr Cletlt11 lntheWlOildttllllllll

lhav triedtoupdal t h o ~ c pat1' that change wllh tune (e g . regulation, , atnw,phenctrend , c ntroltcchn lo y) I have added a few more exampb und J11llhkm' l hen.:1 m r rgan ilution of o p i c ~ . in rc.:,pon >c to r ad r uggc.,llon > . I thanJ.. all thetutl ots, fa ulty, and other\ who have po1111ed out e1 ro ot po01 explanatlllll'> 111 the

h r ~ diti n. Thos who cri ticitc you111 a >Oil v o ~ 111 p11va1e ate yo lnemkOt / cit 1 \ t f\


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mbol

AAA

II .A I

I I C A'',.

(

J( .I

[l/

nr po

rief descriptioncoa l ash con ten tareaurea of city I.

n ~ a n t n Anto in e eq uationcon\lant in Arrhenius equa ti on

(some times cu lled freq uencyfactor )

t ~ o t u n t n unningh m correc onfactoraccclcru tion

leng th parumc tcrmo translcr urea per unit volumechcnucnl species in reac ti on rateequationsuJr-fucl ratJourbltrury co nstantschara ctcnstJc d mensionspolynonuol coefficient sbackground conce ntrationtlll1C parameterconstants m Antome eq ua tionca rbon content of fue lunnmghnm correct Jon factordrug coe ffic1ent

heat cnpac y at co nstant pressureheat ca pacit y at co nstunt volumeconcentrationdJffusJvltyd1ameter or panJcle dwmeteraerodynamic d1ameter. or aerodynamic

diameter of a drop or panicle

NOT TION

UnitsEnglish

1/s

ft/s21/ftft2/f t3

Ibm/Ibmvarious

variousnot used1/ hORwt

Btu/(lbm or lbmol) . FBtu/(lbmol or Ibm) - F(Ibm or lbmol)/ft3ft2/sftnot used

SI

1/s

rnls 21/mm2/m3

kg/kgvariousvariousJJ.g/m31/sCor Kwt

J/(kg or mol) . ocJ/(kg or mol) - oc(kg or mol)/m3m2/smJJ.(g/cm3)o .s


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~ U T A T I O ' l xv ii

D dr meter of bamer It mur cut drame1er.'' the drnmetcr at h r ~ h fl m

the efficrency =50 lDo droplet drameter ft mDm phu c

ga molar ve loc it y lbm uli lt 2 nml/m) 'gas mu ss vcloCIIy lbi fl 2 . ' kgi rn1 'II accclera1on of gravit y fl/\ 1 mlf effeclive slack height II I llH he1gh11n lhc vert1cnl d1rcc trnn. or II I l l

the direction in wh1 c h pnrt1clc nrccollCCied

I f l lenry s luw conslant ulmo,phcrc l uII humidity. Ibm wat er/Ibm d ry arrI I hydrogen content o f fu el wl l WtI I mixing height It mh enthalpy or molar enthalp y ll lu/( lbm or lb mo l ) J/(kg or mo l )h hcighl above floo r a grav rl y \C III cr flh hcrgh of slil fl mh phys ica l stack he1gh1 flh plume ri se fl m

Jm ma s tran sfer fac1orK coeffi cient in pressure d rop cquat 0 'K constant in Lan gmurr equ ati On 1 atm 1 PaK equilibrium cons tant nouli Vllfi U\K turbulent dispcrsron coeffic ient ft1/, m11K mas transfer coc ffi crcnt lhmoV ft 2 ' moVrn1 'Kp equrlibrium constant w1th acti VIllC\ rn v noui vanous

atm


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i i i (11'AnB 1t1mann con\Uint - RIAvogadro's not used 1.38 x lo -

23kg m21K s2numberA fit ienttn modahed Deutsch-

Ande n equ uonA ;an rate con\tant various variousA permeabalaty rt2 m2k ratao of . pe ahc heat' ( pi vA re taon vclocaty cono,tant 1/s 1/sA,.s.. furw I ll nd b kw rd rencta n rate various variousc n t nt1k m tran,fer coefficaent lbmol ft2 s mollm

2 s, length ft mI . len th f caty an downwind direction ft m(an box m o d e l ~

len th of collector an flow direction ft mlen th of P"ton .,troke in. mmaxm hcaght (Fag. 6.9 on ly) not used mmol r flow of nontrunsferrcd lbmolls mollscomponent an laquad phase

I hquad 111011 vclocaty lblfl2 . s kglm2 sI Vi Ulal r ngc COn\tUnt not used km 1Lglm

3I mnlc,ulnr weaght lbm/lbmol glmol

na m\\ Ibm kg; mn" flow rute lbm/s kglsnllrogcn content of fuel wt % wtnumber of punacles, or of people. orof tum' an a cy lone separator

N number. number of transfer unitsI I rll of drop let flow numberls numberlsN ~ c p o r n t o n number = chara teristi cdim 11\1(\IIIStokcs slopp ing number

lit Sec . 21exponent an rutc equation andflrcundhch cquau n

age year yeardi\Utn can darecuon of in terest in ft m

ll ann plume derivation ( hapter 6)II exponent an 1enc' expansionII number of mols lbmo l mol

mol r flow rotc lbmol/s molls) oxyacn content of fuel wt % wt %

pll ncgauvc losao of the H activity( on entrnlaon) expressed inmol/later

I g a ~ pres..urc psi a or atmospheres Pa or mbPo power ft lbfls o r hp kWr pcnctrnuon - co llectioncfhcacncyr vapor preS\urc psi a Pap. ater vapor prcs,urc of laquad water psia Paor mbQ cma saon rntc lbm/sQ volumctnc fl w rate = V . A glsft31s m31sQ(, 3


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o r ~ T I < xixL llqutd volumetnc flow mte ft 1 \ Ill,,,q harge on a panicle c c

q emi ton rate per umt areu lbm/hr rnl gh m;R Reyn Ids numbern Reyn Ids number for parttcle'RH Relative humtdityHumidity

aturation hum1d1tyR umversal gas constant P 1 1/lbmol R m/mnl K(see Append1x A)radius It I l l

r reacuon rate v o u ~ - ~ l r l U U \ulfur content of fuel wt'\ IA.t '\c chmidt numberstandard deviation Vi\ri U\ vnnouT absolute temperature ' R Kquench Lone th1ckne Il l I l l

thi kness It I l lI timelt jl half-life \u verall heat trunsfer cocfftcu:nt lltu/h ' f' . It 2 Wllu1 Ku wind speed ftl> 11\/\u internal energy or molur 1ntcrnul Btu/(lbm or lhmol) J / ( k ~ m mol)

energyv voltage (or potent lUI v vv v lum e It mv vel lty ft/, nt/\v average gas velocity ftj I l l \v, particle or gas ve locity on a crctdur ftf, 11\/\path

n dr p velocity It/' rn.n < dr p vel ity rclutive to hx d Ill> I l l \coordinatesVc ga velocity It/' 11\/\v . relative velocity ftf, I l l \v sta k gas velocity It/' mJv superficial vcloc ty It/' n1f,v termmal velocity ftf, I l l \w mru.. of so lrdv(volumc of gn'

x cake density)w wtdlh of a colic tmg dcvtcc ft mw width of c1ty It I l lw drift velocity (in electro,tuttc It/' n1f,precipitators)

weight fractionw weight of a panicle sample lhm kltw equilibnum amount ad,orbcd lh1nllhm k l f k ~I I acuvity or concentration of compound not U\ed atm . or mollcm1XX m lar hum1d1ty of all.m I water/mol dry ntr

amount emitted ' Lagrangmn lb k ~ tauss1an plume cquat1 n\


23/36

' . v\. \

ATIO.

\ \1 :y

trtr

tr

I )

< )

'11/AAAAl lI II

loqud oment of r n n ~ f c r r c d componen tdt t e1ndependent vanablm 1 racu n m the ltqutd phasem 1number of c rbon tn

hydroc rbon fuelm qu nttty an \cries expansionme n volu of mdependent variab ledt tan e tn x nd y dire tionstndt e tn hydrocarbon fom1ulae.

r lengthsm tton m g ts or vapormol number of hydrogen m

hydroc rbon fuelequtllbnum mol I uc ttonelevnuon or vet1 1 ul dtstnncenumber ol standard devintions

from mean , ( t tmcon)/ / D,.,.,11 )( n tn the logn mutl dl\tnbut ton .t o n d hoed hy Eq ( 12.17)

cu n,tnnttn Freundlich equationlllter mcdtum r e \ l ~ t a n c cdummy vunoblc tn llooding equationdummy vonuble tn lloodtng cqumiondt I In co n,tantporo ttypcnnttttvtty of Ire p u ecumu louvc dtslnhut ton fu n tioncqutvolcnce rat tolllttudelflct ncyIntent heat of vuponnlltonm n fr pothn nn lttcd A/F rntto

V\ ttyktn Ill lliCVI\CO\Ily Lfpd e n ~ tty or molar dens ttyltqutd tty ut nonnul boi ling poi ntv nun c)111

n ~ t a n l t n Gnu\\tun, or n rrnnl ,dl\tnbutmn fun t10ntcfnn Bohlmann constanth z nlnl dl\peNt n coefficient

v nt al dl\pc,.,ton cocflictentpccthC grnvlly Ill II tng CQUOltOnangular vcloctty

lbmolll bmolftvario us

variousft

ftlbmo lllbmol

fl

1/ smixedft

not used

dcgBtu/Ibmft(never usednot usedcPft 2/s(Ibm or lbmol)/ft3lbm/ft 3va ri o usva ri o us

Bt u/hr , ft2 , 0 R4not usednot usedradi ans/s

mol/molmvarious

v ousm

mmol/mol

m

I Smi xedm

8.8 5 x 10- 12 CIV mor 8.85 x 10 - 12 F/m

degJ/kgm

~ l l= I0- 6 mPa sm2/s(kg or mol)/m3kg/m3variousvarious

radi ans/s


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HAPTER

INTRODUCTION TOAIR POLLUTIONONTROL

Air pollution i the pre ence of undesirab le material in air, in quantities large enoughto produce hannful effect . This definition d cs not restri t air pollution to humancau e , alth ugh we normally only talk about these. The und sirable m t e r i l ~ maydamag human health, vegetation, human property, or the global environment aswell a create ae thetic insults in the form of brown or y uir or unpleasant smells.Pollutant are known that may do a ll of these things. Many of these harmful materiabenter the atrno phere from ources current ly beyond human ontrol. However. in themo tden ely inhabited parts of the globe, particularly in the industriali1ed countries,th principal ource of the e pollutants arc human activities. These c t i v i t i e ~ arcclo ely a iated with our material standard of living . To eliminall these activitie lwould cau e uch a dra tic decrease in the standard of living that this action is

ldom c n idered. The remedy pr po ed in most industrial countries i\ to continuethe and control the ir pollutant emission. from them.1 1 OM OF THE HISTORY OF AIR POLL Tl N ONTROL INTHE U ITED TATES O MERI AAlth ugh air pollution control action go back at least as far the thirteenth century[I], mo t of the major effort in thew rid has taken place since 1945 . Before then,other matter were higher on society's priority list (and are still higher in developing


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II< 1'01 1 l CO' rROI I M i l i I RING ) In the 1930s and 1940s a factory smokes tack iss uing a thick plume ofcoun tne'> . ' 1-,mo -c was c nsidered a ig n o f pro perity, and so m e gove rnment agencies me uded

11 10 their official symbol. . . .Before 1945 , industria l a ir pollution co ntrol effort s were i ~ e c t e ~ at controllinglarge -fac t ry emissi n of pollu tants th at had led to c ~ n f l i c t w1th neighbors of the

f a c t o r i e ~ Much of this did not involve governmenta l actiOn, but rather was a respon seto n u i ~ a n c e damage suits or the threat of such suits.B 'tween 1945 and 1969 , as awareness of a ir pollution problems graduallyincr a., d, me worthwhile lo al e fforts to con trol air pollution were initiated, notab in Pittsburgh, Los nge le , and St. Louis. Between 1963 and 1967_the federalgo ernm nt b gan to oversee and coordinate loca l and state air pollution controlcflorts .In 1969 and 1970 , the United States experie nced a great environmental awak-ening. Toc.lay's students may not realize how rapid or drastic a change that was.'om pur, ~ o r n e major newspapers from 1968 with the same papers from 1970. En

ironm '11la l matters were scarce ly mentioned in news papers in 1968, but the samen w..,pap rs had an environmental story every day in 1970. This period saw the passag of th National nvironme ntal Po licy Act and the Clean Air Act of 1970, bothof whi h have had sweeping e ffects and have grea tly changed our way of dealingwith a1r pollution . imilar changes took place throughout the industrial world atabout th ' .,arne tim e, with s imilar effects.

Th' sudd n and sweeping change in air pollution law brought about by the' I an ir t of 1970 came as a grea t surpri se to most major American industries.At hr'. t th I aders of the older smokestack" indus tries (steel, copper, some electric

pow r) fou >ht the new regu lations, in the courts, in the press, and in Congress.Tw nty five years later the ir successor mo stly have decided that the air pollutionr gulution > ar h re to stay and that their goa ls should be to influence the regulatorypr .. .. to mak' the regulations as c lea r and practical as possible and then to complywith th ' r gulations in as efficient and economi ca l a way as possible. The best ofth' industry I ad rs arc always looking at the nex t gene ration of regulations so th at

h n thos r ulations appear, they will be prepared for them and will not have tohan what th y did for today's generation of regulations. Most major industri estr to b m least as well informed (a nd if possible etter informed) on air pollutiont ' hnical matt rs as any of the other participants in th e regulatory process.

In th' lat 1980s, a n w theme entered the a ir pollution arena: global air pol luti n . ntil 1980, rn st air p llution problems were perceived as local problem s.Th' pollutants of interest had sho11 lifetimes in th e atmosphere, or were emittedin .,uch '.ma ll ~ u a n that they were not perceived as a problem far beyond thepia ' from wh1ch they were emitted. Thus , it seemed logical to Jet local or statego mmcnts deal with th m. ( If a stinky factory provides jobs , the conflict betweentho.,' who njo_y the econ mi benefits of the factory and those offended by its sm e llcan be ".cttlcd 1n a I ca l election.) In the 1980s, three problems emerged involvinglnngcr- ltvcc.l p llutants and p llutants that are transported a long way before th eY


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1 in0u O.la, tub r ul os is, and typhoid fcvcr. the e f f e of' air pollut tOll Oil health , wh I hare t wand cumulative, were .cldom observed . A.., w have lea111ed to ptl'Vl'nt ortreat th e e di cases, we have doubled our average life ~ p a n . Mil vrvtng long enoughto di f I ng-term disea es su h as ar1 r i o s c l e r o ~ i ~ . heart mallunctton ... 'trokc.mphy ema, and cance r, all of which arc related to environm rita I fac tor,, ntcludtngir IIuti n. he sa me observati< n can be made about c tgar He o . , m o ~ r n g : bel or

'Alth ugh the environmental move ment wu' mo,tly an acttvtty of the upper nuddlc d.o e'. thl poor11ft m st ften c x p o ~ e d 10 more ~ e v e r e atr pollutton (and other en\lronlllenr.ilnwlt,ithnn .tre the n lhThe ht he t n entrations of air pollutnnt' arc found 111 thecentr.o llotoe'. "here poor people II\e. nor onuburb where wealthier people hve. The pncc ol home' on Ln i \ n ~ t c l c ' related tolox.ol .ur pollut.orllconcentra to ns, lh c ncar thebcache' or hgh on the foothill, , hcoc the .ur polhot.tnt u>ntentr.ttoo>n rclowe I, n nnall ycommand thehi ghc \1pncc' The ';omc ''true olmdu,tn.oil'')"("llre. onil f l < ~ r people1110rk J b woth ..cvcre cxpowre to potentially hannfulmatcnal' Th" " ,,),o true ol the l


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4 IR POU.liTI ( STROll Gl Ill Gtr at the c co ntagi u di ea es, smoking probably had l i t ~ l effect on

v r 11 li pc tan cy . N w that the e other causes of death are practically g o ~ eltv 1 ng en ugh that m king ha a real effec t on life expectancy. So also With

lluti n.t 1, u ful 1 c ntrast the air pollution situation , for which we have taken ac-ntly with water p Jlution, for which we have had active programs forr ntury. ' h w r t water problems were caused by c o n t m i ~ t i o n of r i n ~

10 w 1 r with human s wa c. This quickly spreads cholera, typhmd, a n ~ amoebictl . nt ry. h . r diseas s ar udden and dramatic in onset and often swiftly fatal.h 1r nn ti n with polluted water is easily demonstrated. Thus, we responded toth w l l r pollution problem much sooner and more vigorously than we have to thei polluti n problem . .

1 nc of th effects fair pollution on health (see Chapter 2) IS much lessc J 1m 1t1 than that for water p llution. One can se ldom point to a pile of corpses and.., 1 h y di d of air p lluti n, as one ca n after a cholera outbreak due to pollutedw t . h fC cts arc mor like those of smoking; we seldom say, He died of.. m k1n , but we know that m king has been shown to decrease the life expectancynf th m k r and t increase the incidence of certain well-defined illnesses in-.muk r > 1nd in those wh breathe econdh and smoke. The fact that so many peopleto tutlan du ated people- smoke demonstrates that this type of argument is not1-. rsutsi as the sight of the corpses after an epidemic spread by water pollution.M 10 p ,pi d not tak very . eriously the loss of life and health due to air pollution ,It\.. th t du to smoking, b cau e th ey believe it is only statistical.I h If ts of air polluti n and of smoking are also analogous in that many

opt ho hav livd in bad ly air-polluted e nvironments all of their lives have II nt lungs and h arts . imilarly, everyone knows someone who lived to be a

1 r u. and smok d igarcttes or cigars eve ry day. Those examples exist ; the unt r ampl s died younger. of diseases caused or aggravated by air pollution orm kan .

Publi awareness of air p llution developed at a period when the problem wasI .. .. er in many respects than it had been previously. Before the introductionf natural gas as the principal fuel in most U.S. cities, winter air was much dirti erWith al s >t than it is n w. Likewise, early in this century, the emissions of sulfur

til id fr m copper sm lting in ci ties such as Tacoma, Salt Lake City, El Paso, andna onda w rc much g reater than they are now. At those times there must have

h n dissatisfaction ab ut these sources of pollution, but presumably not at the levelha had in the past few year .Thi in rcase in awarencs is partly ex plained by the increased wealth of theuntry. a m ntioned before. We once thought these pollutants were necessary

n m ~ a n t s f a pro. per us economy; we now know otherwise. Similarly, wen hevcd that n thing c uld be done about such problems. Now that we havelearn d t re d the geneti c de and put people on the moon, it is harder to argue

~ h t w ann t air pollution . We can; th i s book explains the technical basesand s me f the details of how to do it.


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INTRODUCl iU N 10 tO 'ITRUl 51 DIRTY AIR REMOVAL R EMI 10 TR L?E mpl 1 1 The area of the Los Angeles basin i 40 3 quare mile\_The heavilypollu t d air layer i a umed t be 2 ft thick on average. ne soluti n to o.

ngel ' pr blem would be to pump thi s con taminated air away_ upposc that wewi h t pump out the Los An geles basin every day and that the air mu\t be pumped0mil t the de ert near Palm prings _ We assume the residents of Palm pring w n't omplain_) A ume also that the average ve locity in the pipe is 4 ft/s . stimatcthe req uired pipe diameter.Th flow rate required i

_ H _ 4083 mi2 2000 f t (5280 ft/mi) 2 _ 9 ft 1D.t - 24 h . 3600 s/h - 2.63 x 10 srn '

= 7 47 X 107nd th r quired pipe diameter is

= 4Q =y;v 4 X 2.63 X JO I ft 1/s = 915R ft = 2791mrr x 40 ft/s Thi i about ix times th height of the tallest man -made structure, and far

y nd ur urrent tructural engineerin g capabi lities. imilar calcula tions (Problem1.1) h w that the power required to drive the fl ow ex eeds the amount of electricalpow r generated in the Lo Angeles basin . We arc unlikely to solve our air pollutionp bl m by pumping away the polluted air. although th is solution is stil l frcqu ntlyp d. In tead , we mu st dea l with th ose problems by reducing emissions, theprincip I ubject of the rest of this book.

1 4 PROBLEM OR A FAMILY OF PROBLEMS?In T ble 1.1 we ee emi sion e timatcs for the major man-made pollutants for theUnited t te in 1997 . From this table, we sec the followin g:

ix individual pollutants listed. which arc the major regulated pollutantsnited tates. Th ere is a much longer list of other pollutants, emitted in

mu h le er quantitie and regul ated in a different way in the nited States (sech pt r and 15 ).

2. me f the p llutant come mostly from tran sportation (motor v e h i c l e ~ andthe c me mo tly from industri al sources_

. The re i n entry for General air pollution.The public think' in terms of gcneralir IIuti n and wonders if the problem is mostly indu,try (them )or auto > (us).


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6 IK POLL nO'I CONTROl l. 'GI ffKING

S z co NO, voc Pb0.7 1.4 67.0 11. 6 7.7 0.00052l'r,m,pnuuon 17 .3 4.8 10 .7 0.9 000050l'uel combu\ llon 1.1 6. 1 0.9 9.8 0.0029lndu,lnul pr C\\CS 1.3 1.70.0 9.6 0.3 0.8MI\CCIIII1 OU\

luJ,ll 3. 1 20.4 87.5 23.5 19.2 0 .00391970Jolal 65% 78% 116% 70% 1.7%

I' 1 pa n1cuhuc matter, 10 1or ,muller; ' hnpter 8. so , =a ll >ulfur ox ides, mos tly S02 ; see Chapter I I .,urt>un r n o n o ~ l l , e hapter 1 NO, all nurogen ox1de>, mostly NO and N 01 . The mass shown 1s based on a 0llapp ly limited so lutions to parts of the family of air pollution problems.

4. h o m 1970 to 97, th ' United States has mad e s ignificant progress in reducing m i ~ : i o n s of lead (mos tl y by taking lead out of gaso line) and modest progress

t 'du ing emissions of the other major pollutants. The air pollutant emission' 'tuation can he roughly approximated by

I . (economic activity)pu a ll on per person (pollutant emission .s )

per umt of economiCactivity( I . I )

in the environmental awakening of 1969- 1970, the population of the United t a t ~ has increased by about 30%, our econom ic activity per person by about 80%.and ur m tor vehicle usag' by about a factor of 4 . But the pollutant emissionsper unit of ccon mic activity have declined steadily becau e of stringent program s


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I IH.lltJl( 110 tO \IN. l Olll IIO dD,IW.Ol 7of ev r-m r -effe tive pollution control eqtupmcnt ha-. allowed u' to llllep' taken to date havee n i rand cheaper than th e ones we will have take in the fulllrc.

1 5 N TRANSPORT R EPTORSFigur 1 1 i a hematic of the air pollution proce''. ome '>Ourc..: ..: n11l\ pollutant\to th atm ph re . The pollutants arc tran-.portcd. diluted. and modified cht'llllca ll yor phy i lly in the atmosphere; and finally th ey rcat:h \01111. rcc..:ptor. \\hen: theyd mag health, property, or so me other part of the .:nvironment. Some ol th..: poilutan ts ar removed from the atmosphere by natural proce,-,e.., , -,o that the} lll'll'l findarc pt r.

In thi b k, in any dist:ussion of air pollution. or any > tudy of the regulatory\tru tur fair pollution control. one f i n d myriad detai ls. One aJ.,o hnd-. that what11 d n f r nc kind f source or one particular pollutant i .. diffcr..:nt from what i..,don f r n thcr . ourcc or pollutant. orne of c ~ c diller rK..:.., r..:..,ult frofll h1..,ton nccid'nt. and me result from the very difkr..:nt -,ourc..:.., and controltc < hnolo g1 ,lor th vari u major pollutants. Faced with thi-, di vcr..,ity of tkt;ul..,, lllll' would dowe ll t I k asionally at Fi g. 1. 1 to -.ee ho w that part1 cul;u dctad fit, rnto th..:ov rail air p lluti n sc hematic shown here.

In ig. 1.1we also sec a major r e ~ o n wh y air pollution ' dllklt"llt rom wa terpolluti n r indu strial hygiene . I f the ~ a m . . : fi gure were drawn lur wat


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IR POLLUTIO COI (fROL ENG IN tER I G

rkcr in fa toric and other workplaces, is often concerned with the same emis-n a i the air p llut ion control engineer, but the industrial hygienist normallya m r ea ily defined tran port path between emission and those affected, and

rar ly d al wi th econdary po llutant s.ev rat ft hc e idea are illustrated in Fig. 1.2 , where we see smoothed averageo ne ntration of four air po llu tants fo r one day in Los Angeles . CO and NO are

prim ry p llutants, emiued most ly by automobil es (Chapter 13) , as is hydrocarbonH ), n t . hown on this figure . T he peak co ncentra tions ofCO and NO occur duringth m min mmute period . N02 and 0 3are secondary pollutants formed in the

sph rc by a c mplcx set of reactions, summari zed (see Appendix D) asN + H + 0 2+ unlight - N02+ 0 3 (1.2)

} r r r r -... ---- 50

NO)40 40

l61 ) \0 E0 .30 0 .c S/

ciu._0/ 0c:0

J() ()bc:.20 .)c:0u

CliO 10

0100 0600 0900 1200 I500 1800 2100 2400Time of day

. mooth d vern c daily co nce ntra ti On\ f . e lected ll utant s in .4I r\ C th progr on N NO po . . Lo s An geles. Californi a. July 19 1965 [3d 2 l and the d1fferent beh f .P1 eh m1ca l rca lion m the a tm sphe re. av torCO. whtch does no t undergo


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l Q IR POU.UTION O ~ R O L I GI EfRI GPo= Q6 P 1.4)

T t the volumetric flow rate, 6. P the pressurewh r p i. the power requtremen , bl

inc.:r a acr the blower, and T the efficiency of the blower or of the m o t ~ r - ~ w e rcombinati n. Thi eq uation i. correct in any set of units. One regularly sees It wnttenQ6 P lp 33,000 1.5T

htch i > nly rr ct if the power is expressed in horsepo:-ver, the flow rate in ~ u b i cr. t r minut (cfm). and the pressure in lbflft2 . That ts an uncommon umt forpr .,.,ur , s ne is quite likely to misu e this equation. If we use the more commonlbf/in (psi). then thi s become

= QD P . = 0.00436 QD.P (1.6)Po T 33,000 Twhi hi-. nly correct for horsepower, cfm, and psi . . .

In this book all equatio ns arc of the type of Eq. ( 1.4), correct many consistent, t ,r units, except if th rc is an explicit statement to the contrary. Some of thepmbl ms ask the reader to co nvert from the universal form to practical forms like

( 1.5) and ( 1.6 .In th nited tatcs, a conce ntration expressed in parts per million (ppm) isa l m o ~ o t always ppm by volume or by mol if it is concentration in a gas, and ppmh muss or weight if it is conce ntration in a liquid o r solid. (For a liquid or a solidwith u sp ciflc gravi ty of 1.0, such as water or dilute solutions in water, ppm is the., 1m a-. mg/kg, which is a lso widely used. This mixed meaning for ppm continuesto b a sour of co nfu sion when both liquid or solid and gas concentrations appearin th sam problem. One ofte n sees this concentration written as ppmv, to remindth t ad r that f r gases it is most often ppm by volume. (The same is true of parts

r billi n; ppb =11.g/kg for as lid or liquid material with specific gravity of 1.0.)Wh n standard conditi n. for a gas are referred to, there seems to be only one

ch i f r pr ssur . the standard atmosphere whose values in a variety of systemsof units ar . hown inside the ba k cover. Unfortunately, there is no comparablea r m nt a. to which t mp rat urc should be used . Values of 0C, I8C, 20C, and25 ar us d. Thr ughoutthis book, unless stated otherwise, air and process gasesnr as.,um d t b at I standard atmo phere and 20C = 68F). The properties ofair and wnt rat thi s temp raturc and several others are shown inside the back covera-. w II. ( n ~ rtunatcly, many PA reg ulations are based on a standard temperatureo 25 = 77F.)1.7 TH PLA FTHI BOOK

h r ar many p ssiblc ways to arrange an Air Pollution book, no one of which\C . . to please all readers. Th plan of thi s book is first to discuss topics thatar comm n to all pollutants, and then to di scus individual pollutants. For each


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INTRODUCTION TO IR P O L L U T I O ~ ONTROL

pollutant, the c ntrol te hnol gy i adapted to the sour es and the phy ical andchemi In ture f that pollutant. hapter 1- 7 cover general t pies in air pollution.

hapter - 12 cover the four major air p llutants that have been and con tinue t bethe f u f m t f ociety's air p lluti n control efforts. hapter 13 covers m torvehic le , which play a uniqu e role in air pollution and contribute significantly tourban air p llution problems. hapter 14 discusses larger-scale problems. includingglobal nes. hapter 15 trea ts five additional specific air pollution topics briefly.

1 8 MMARYI Air p llution i. the pre ence of man-made harmful materials in the air, in 4uantitie large en ugh to produ e harmful effects.2 Publi interest in air pollution was low before 1969. About that time , it im:reascd

dramatically, and has remained high.3 We are unlikely to olve our air p llution problems by blowing the polluted airaway; we will have to so lve them by reducing pollutant emissions.4 There i not one a ir p llution problem but rather a family of related problems .

We are unlikely to find a cheap, easy way to so lve these problems. l n ~ t c a d . wewill have to make many sma ll steps to reach our air quality goab. and thc-.c willpr bably be more expensive th an the steps we have taken so far.

S The verall air pollution problem takes the following form : emissions tran.., port, dilution, and modification in th e atm osphere effects on people, property.and the environment. Although the details may differ from pollutant to pollutant.all fit thi pauern .

6. me fthe most important air pollutants arc secondary pollutants, formed in theatm phere from primary pollutant pre ursors .7. Ppm m an ppm by volume or mol when applied to g s c ~ and ppm hy rna....., or

weight when applied to liquids and solids.8. r all pr blems and examples in thi s text, unless stated otherwi-.e. the p r e ~ . u r cI atm and the tempera ture is 20 = 68oF (sec inside the back wver).PR LEMee mmon Unit and Values for Problems and Examples. inside the hack cover.1.1. In xamplc 1. 1:

(a) timate the pres . ure drop r quircd.(b) timate the pumping power requ1red.

ee any fluid mechanics textbook for m e t h o d ~ of makmg t h c ~ c c ~ t l m a t c o1.2. (a) In Table 1.1we see that 57 wt% of the li>tcd pollutant\ arc 0 Doco, t follow from that

table that 57 percent of the air pollution problem tn the n1tcd State' a CO problem?(b) The arne table shows that 57 wt % of alithe \ ted pollutant' come from tran\portation(m tly aut m biles) .Doc' it follow that 57 percent of our nauonal a1r pollut1on problem

i an automotive problem?(c) If the answer to these questions no. explain your answer.


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12 IR U.lrrl GINELRING

1.4 .1997

(b) h re on ble to make thi s compari son? Why or why not?I . n o ember 4, 199 . Jos Angel onche llo, the secretary of the second -larges t political

party in Me i o PAN), wrote to the mayor of Mexico City, proposing that four helicopterse t rth ity todi\perse the air pollutants. He sa id, Extraordinary situations require

lutions.... 1 refer 1 the use of the helicopters of the Federal District , as ifth y w re huge v e n t i l t o r ~ 1 cause turbulence and vertica l co lumns of contaminated a irto dtmtnt\h the poi\oning in the stree ts. [6 omment on th e practicality of this proposal.

k I h th ir now gcncrutcd by hovering helicopters.1.1\. 1 law f d i m i n i ~ h i n g returns is widely di cussed in economonics tex ts. The author'sI vuril ample is th ut the first h ur of cleaning a messy house produces a very visibletmp uv m nt in its appearance, but that the nex t hour of cleaning effort produces less visibleII 't, nd ~ u b s e q u nt on ~ e v e less. uggest other exam pl es from daily life of the law of

duntnishtng r tum . ugg st how it app lies to air pollution co ntrol.

II lhd , E A lllM oncal Revi w of Atmospheric Pollution , in World Health Organization M ono-/lrrlfllt Strit .\, No 46. cncvn. 1961 .2 Na11mwl ir Q11al11y01td m1


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