membarane technic in ro

7/23/2019 Membarane Technic in RO

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A&M A&M University

Texas

Environmental Challenges: OverviewFacing Industry

Dr. Pedro Medellín Milán

Universidad Autónoma d

eSan Luis Potosí

Dr. Mahmoud M. El-Halwagi

e!as A"M Universit#

Monserrat $haire% Llamas

(Part III)

Pro&ess 'ntegration (or Environmental $ontrol in Engineering &urri&ula



A&M A&M University

Texas

Let’s consider a typicalre ning industry with anaverage !""#""" $$l%day

capacity as the one presentedin gure ! on the ne&t slide'

In this process# the largestsource o pollutants such asphenol# ammonia and sul deresults rom the catalyticcrac ing unit' Considera$leamounts o thesecomponents and# high levelso *O+ and CO+ are oundedin the oily sour water coming

out o the ractionators in thedistillation units'

P+, LEMS A EME

PA+AME E+ /AS E 0UA ' 'ES A DL,ADS )l1s2da#*

,ater !- -./ -""

*O+ 0 !1 """

CO+ /. """

2uspended 2olids / .""

Phenols .""

2ul de 1 -""

34 / 53 ! 6""

Oil 0 /""

7he wastewater produced in thosesections o the process are loaded toa primary treatment unit (8PI

separator)# and the resulting streamshows the ollowing characteristicsgiven 7a$le/'!:



A&M A&M University

Texas

A t m o s p

h e r i c

d i s t i l l a t i o n

Vacuumdistillation

Coking

CatalyticCracking

Hydrocracking

HydrogenProduction A

m i n e

Desulfurization

Treating

Desulfurization CatalyticReforming

AlkylationGas plant

Amineplant

B l e n

d i n g

Treating

Gasoline

Jet Fuel

Kerosene

Heating oil

Gas

Naphtha

Lubricating oil

Grease

Wax

Coke

Industrial Fuel

Asphalt

NaphthaGas

Fuel Gas

ButaneGasoline

Naphtha

L G ! Light

gases

NaphthaGas

NH "

H#$

H#

NH "

H#$

H#$

C% #

&iddle 'istillates

NH "

H#$

Gas %ilsNH "( H#$

NH "

H#$

C% #H#

H#

HCNH#$



A&M A&M University

Texas

7he primary e9uent is then carried to secondary treatment#where the levels o *O+ 0# CO+# oil and suspended solids arediminished and can $e neglected or this open ended pro$lem'enerally# sul ur compounds are di;cult to remove# hence wewill not deal with sul de treatment and only consider thecomposition o secondary e9uent as shown in 7a$le /'1:

$om3ound 4low )l12hr* Mass4ra&tion

,ater -<0 !0" "'<<<.-.1

34 / 53 0.'// "'""""./<

Phenol //'// "'""""6=<



A&M A&M University

Texas

7he re nery has to ul ll the e9uent limitation guidelinesdictated $y the Code o Federal >egulations (6" CF> 6!<'11)#stated $elow:

*O+ 0

722

CO+

Oil and grease

Phenolic compounds

8mmonia as 3

2ul de

7otal chromium

4e&avalent chromium

p4

1.'1 !<'0

1!"'"

.'6

"'1!

!.'.

"'!.

"'6/

"'"/0

(?1?)

!0'-

!1'-

!"<

6'0

"'!"

.'0"'".1

"'10

"'"!-

(?1?)

Ma!imum (or an# 5da#

Average o( dail#Ma!imum values (or67 &onse&utive da#s

shall not e!&eed

Pollutant or3ollutant 3ro3ert#

Metric units (kilograms per 1,000 m 3 offeedstock)



A&M A&M University

Texas

In order to reach the CF> re@uirements# the secondary e9uentwill $e carried to the tertiary treatment and the consideredoptions or this are:

7o diminish the content o phenol and ammonia $y SteamStri33ing

7o remove phenol $y +everse ,smosis

For the last case we will suppose that there is no ammonia in thestream# so that the only pollutant to $e removed is phenol:

$om3ound 4low )l12hr* Mass 4ra&tion

,ater -<0 !0" "'<<<<01!

Phenol //'// "'""""6=<

7O78L -<0 !./'// !



A&M A&M University

Texas

0UES ', S8 Is the level o separation achieved with each o these tertiary

treatment methods good enough to satis y the limits imposed in theCF>A

Could the target concentration $e reached $y modi ying someoperating conditionsA I so# how would these modi cations aBect thecostsA

8ccording to the nal separation and the cost analysis# which isthe most suita$le technologyA

,hich method would you recommend or secondary wastewatertreatment ta ing into account *O+ 0# CO+# suspended solids and oilamounts i secondary e9uent have to $e low enough to meet theCF> regulationsA

Is any o the two proposed tertiary methods convenient oradditional removal o *O+# CO+# suspended solids or oilA



A&M A&M University

Texas

For the >everse Osmosis calculation the ollowing data is

re@uired:

Fi$er length# l: "'=0" mFi$er seal length# l s: "'"=0 mOuter radius o $er# r o: 61 & !" 5- mInner radius o $er# r i: 1! & !" 5- mem$rane area# 2 m : !." m 1

EO E7>IC8L +878

I3PD7 +878

a&imum ow rate per module: "'6-" g%s

inimum ow rate per module: "'1!" g%sa&imum eed pressure: 10'0. & !" 0

Pressure drop per module: "'6"0 & !" 0

Pure water permea$ility# 8: !'1" & !" 5!"

2olute transport parameter: 1'6/ & !" 56



A&M A&M University

Texas

Industrial ,astes 7he characteristics o industrial wastewaters# their composition# ow and volume diBer considera$lyamong industries depending on the speci c process carried on'

8s seen in section 1'/# wastewater rompetrochemical and petroleum re ning industrycontains ha ardous chemicals as hydrocar$ons#phenols# ammoniacal nitrogen# hydrogen sul de#sul uric acid# etc'

7hus# the environmental impact o thesewastewaters depend# $esides their collectivecharacteristics such as $iochemical o&ygen demand(*O+)# chemical o&ygen demand (CO+) andsuspended solids (22)# on their content o speci cinorganic and organic compounds' 7his su$stanceswill dictate the most suita$le treatment method'



A&M A&M University

Texas

EP8Gs program to control wastes is$ased on the ollowing hierarchy:

8voidance>e5use

>e5cycling>ecovery o energy

7reatment

Containment+isposal 7he treating o wastewaters canta e place at diBerent points in theprocess'

Options for controlling industrial wastewaters

,astewater can $e:

H Pretreated or discharge tomunicipal treatment sources'

H 7reated completely at the plantand reused or discharged directlyinto receiving waters'

H 7reated at the point o generation'



A&M A&M University

Texas

Classification of Wastewater Treatment Methods

iologi&al nitrogenremoval

ioaugmentation

A&tivated sludge

E!tended aerationAnaero1i& 3ro&esses

+otating 1iologi&al&onta&tors

Se9uen&ing 1at&hrea&tors and tri&:ling

;lters

$ar1on adsor3tion

Distillation

4iltration

Steam Stri33ing

,il and greases:imming

,il2water se3aration

Sedimentation

Mem1ranete&hnologies

$hemi&al ,!idation

$hemi&alPre&i3itation

$oagulation

Dissolved air <otation

Ele&tro&hemi&alo!idation

4lo&&ulation

H#drol#sis

eutrali%ation

Solvent E!tra&tion

'on E!&hange

C4E IC8L P4 2IC8L *IOLO IC8

L

!D"#TR A$ %A#T&%AT&R TR&AT'&!T '&TH(D#



A&M A&M University

Texas

Classification of Wastewater Treatment Methods

iologi&al nitrogenremoval

ioaugmentation

A&tivated sludge

E!tended aerationAnaero1i& 3ro&esses

+otating 1iologi&al&onta&tors

Se9uen&ing 1at&hrea&tors and tri&:ling

;lters

$ar1on adsor3tion

Distillation

4iltration

Steam Stri33ing

,il and greases:imming

,il2water se3aration

Sedimentation

Mem1ranete&hnologies

$hemi&al ,!idation

$hemi&alPre&i3itation

$oagulation

Dissolved air <otation

Ele&tro&hemi&alo!idation

4lo&&ulation

H#drol#sis

eutrali%ation

Solvent E!tra&tion

'on E!&hange

C4E IC8L P4 2IC8L *IOLO IC8

L

!D"#TR A$ %A#T&%AT&R TR&AT'&!T '&TH(D#

Physical%Chemical processes i

chemical agentsas coagulating

agents areadded'



A&M A&M University

Texas

Con)entional*reat+ent

High,-ualit.*reat+ent

Waste/atertreat+entprocess

It’s a com$inationo physical#

chemical# and$iologicalprocesses

P+EL'M' A+=+EA ME

P+'MA+=+EA ME

SE$, DA+=+EA ME

AD>A $ED+EA ME

4eedwastewater

stream

o dis&harge

orreuse2re&#&ling



A&M A&M University

Texas

>emoval o grit# de$ris ande&cessive amounts o oils or

greases'

%aste)ater pretreatment plant*




P+EL'M' A+=+EA ME

P+'MA+=+EA ME

SE$, DA+=+EA ME

AD>A $ED+EA ME

4eedwastewater

stream

o dis&harge

orreuse2re&#&ling



A&M A&M University

Texas




P+EL'M' A+=+EA ME

P+'MA+=+EA ME

SE$, DA+=+EA ME

AD>A $ED+EA ME

4eedwastewater

stream

o dis&harge

orreuse2re&#&ling

>emoves near to 0"5="J o22# 1050"J o *O+ 0 and -0J

o oil and grease'

$lari;er



A&M A&M University

Texas




P+EL'M' A+=+EA ME

P+'MA+=+EA ME

SE$, DA+=+EA ME

AD>A $ED+EA ME

4eedwastewater

stream

o dis&harge

orreuse2re&#&ling

7he reached removal is up to.05<0J o *O+ and 22 and

-0J o CO+'



A&M A&M University

Texas




P+EL'M' A+=+EA ME

P+'MA+=+EA ME

SE$, DA+=+EA ME

AD>A $ED+EA ME

4eedwastewater

stream

o dis&harge

orreuse2re&#&ling

>emoval o :H8dditional organic andsuspended solids'H3itrogenous O&ygen +emand(3O+)H3utrientsH 7o&ic materials

Mem1ranese3aration

8lso called? ertiar#reatment

@



A&M A&M University

Texas

P+EL'M' A+=+EA ME

Objective: 7o separate su$stances which can causepro$lems to puri cation plant e@uipment' 4eavyinorganic solids such as sand# gravel# metal orglass are removed' 7he collected de$ris is usuallydisposed oB in a land ll'

Used processes: ainly sedimentation andltration'

Used e uipment : *ar screens# comminutors andgrit cham$ers' enerally the wastewater enters a$ar screen rst to remove large si e solids andthen passes to a grit cham$er'

Grit Chamber

P+'MA+= +EA ME

Objective: >emoval o organic and inorganic suspendedsolids# oils and greases' 8lso removed are some organicphosphorus# organic nitrogen# and heavy metals associatedwith solids' Colloidal and dissolved constituents are notaBected'

Used processes: 2edimentation# otation and oil%waterseparation'

Used e uipment : Clari ers and settling tan s or suspendedsolids removal and 8PI separators or oil%water and solid

Clarifier at the 'ain %aste)aterTreatment Plant in (akland



A&M A&M University

Texas

2uspended lm systems: icroorganisms are suspended in wastewater and once theya$sor$ nutrients# reproduce and then are settled out as a sludge' 8 portion o the sludge ispumped $ac into the incoming wastewater as Kseed microorganisms while the other part issent to sludge treatment' E&amples o such systems are e&tended aeration# activated sludge#se@uential $atch reactor systems and o&idation ditch'

Used processes: 7hree approaches are used to accomplishsecondary treatment Fi&ed lm systems: icroorganisms grow on su$strates (roc s#

plastic# sand) over which the wastewater is spread over' 7he lm omicroorganisms grows and thic ens while the nutrients area$sor$ed' 2ome e&amples are rotating $iological contactors (>*C)#tric ling lters and sand lters'

SE$, DA+=

+EA MEObjective: +ecomposition o dissolved organic matter $y means o using $iologicallyactive sludge' Consist o the $iological treatment o the e9uent rom primary treatmentto remove the residual organics# suspended# colloidal and dissolved solids'

Lagoon systems: 8re shallow ponds designed to hold wastewater orseveral months while is treated through a com$ination o physical# $iologicaland chemical processes' 2ome aeration devices can $e added to rise thesystem e;ciency' 7he most common types o lagoons are:

8naero$ic lagoons 3aturally aero$ic lagoons 8erated lagoons

Treatment process )ith a RBChttp+,,)))*oleau*fr,

http://www.oleau.fr/

http://www.oleau.fr/



A&M A&M University

Texas

!e"nition: 8ny process applied a ter secondary treatment designed to produce ane9uent o higher @uality to protect the receiving waters or to provide reusa$le wateror its urther domestic and%or industrial recycling (cooling water supplies)' 7histechnology encompasses all unit operations not commonly ound in the typicalwastewater treatment'

#lassi"cation of advanced $aste$ater treatment process:

AD>A $ED /AS E/A E+ +EA ME

%&'% '* %'& M&+%

#OM +&!O-O. # -/ *2 # -/# &M # -

%'& %M&+%

*2 #O# &M # - %'& %M&+%

By the type ofprocess flo)

scheme utilized

K7reatment processin which unit

operations areadded to theconventional

secondarytreatment'

K7reatment processin which $iological

and physical5chemical processes

are intermi&ed toachieve the desired

e9uent'

Com$ination o$iological and

physicochemicaltreatments'



A&M A&M University

Texas

H0$IC%CH1&ICAL2%C1$$

BI%L%GICAL2%C1$$

not er $a4 to classif4 advanced $aste$ater treatment is to di5erentiate according tot e desired treatment goals6 2ome e7amples are presented ne7t6


'

+,

E

+EM,>AL

Al:aline air stri33ing

'on e!&hange : ,astewateris passed through a porous$ed o organic resin wherecationic and anionic ione&changers react with cationsand anions# respectively# orremoval or recovery'

rea:3oint &hlorination

Consist o two phases:3itri cation or rst phase: Occurs in an aero$icenvironment and a than similar to that or the activesludge is used to o&idi e the ammonia to nitrate'2econd phase: Occurs in an ano&ic (without K ree o&ygen#i'e'# O 1) environment where the nitrates are denitri ed tomolecular nitrogen $y means o diBerent genus o $acteriausing the nitrates as o&idi ing compound in place oo&ygen'

///3+ech,che+3co+4 about4/.+an3ht+l

http://www.mech-chem.com/about/wyman.html





A&M A&M University

Texas

CH1&ICAL2%C1$$

BI%L%GICAL2%C1$$


PH,SPH,+US

+E

M,>AL

# &hemi&al 3re&i3itationusing multivalent metalions as iron salts oraluminum &om3ounds su&has (erri& &hloride or alum)aluminum sul(ate*

Phos3horus removal is done 1# en&ouraging PA,Bs)3hos3horus a&&umulating organisms* to grow and&onsume 3hos3horus 1# using an anaero1i& tan:3la&ed ahead o( an a&tivated sludge aeration tan:.

Alum treatment at #-ui.. $ake/ $a)rence0ille/ !1 http544///3alliedbiological3co+4treat+ent63ht+l

Anaero.icreactor

Aero.icreactor

Clarifier

#econdaryeffluent

P cleaneffluent

,aste activatedsludge with Prich $acteria

8s these methods convertdissolved phosphorus into

particulate orm it is common touse sand lters as nal stage'

http://www.alliedbiological.com/treatment1.html

http://www.alliedbiological.com/treatment1.html



A&M A&M University

Texas


,

HE+

+E

ME

ME

H,DS

Adsor3tion with a&tivated &ar1on. It is appliedas advanced treatment or the removal o non5$iodegrada$le dissolved organics or as a secondarytreatment replacing conventional $iological treatment'2ome molecules as methanol# ormic acid# and sugars

are not remova$le $y t his method'

Polishing 3onds. Dsed to o$tainadditional suspendedsolids removal'

7reatment can $eaero$ic or acultative(a com$ination oaero$ic and anaero$ic$iological activity)'

Mi&rostraining ' ethod used or removalo additional suspended solids andassociated $iochemical o&ygen demand' 7heprocess involves the passing o an e9uentthrough a hori ontal rotating drum with altering a$ric &ed $y a porous screen'

Post-aeration ' ethod used tomaintain certain dissolved o&ygenlevel' 7his is accomplished $y

mechanical aeration# diBusedaeration or cascade aeration'

4iltration. Dsed or additional elimination o suspended solids and $iochemical o&ygendemand' 7hese processes include sand ltration# constructed wetlands and mem$raneltration'



A&M A&M University

Texas

7he most common e&amples used in wastewater treatments are presented in the

ne&t ta$le:

http544nett#63gec37p4CC*8'A*A4WA*124IN*2%'9C*I%N4ht+l4Water,::63ht+l



A&M A&M University

Texas

#3i&al Petroleum

+e;ner# ECuentreatment Plant

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Activated SludgeProcess

*his e;;luent is thentreated in a central

;acilit. called <end,o;pipe< treat+ent as it isnor+all. i+ple+entedas the last stage o; theprocess be;ore the

It is co++on in +ost re;ineriesto collect all process

/aste/aters and to co+binethe+ into a single /aste/ater3

strea+ is disposedo; or deli)ered3 *he

end,o;,pipe

treat+enttechnolog.

includes biologicaland che+ical

s.ste+s3

8dapted rom K8n IntegratedE&pert 2ystem orOperating a Petroleum>e nery

8ctivated 2ludge Process,ei$o uan# ichael M'

2tenstrom # 3aci 4' O gur#

+avid O rent



A&M A&M University

Texas

#3i&al Petroleum


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The American Petroleum nstitute 2AP 3 separator is a long rectangular tank that

operates on the principle o; strokes la/ /hichde;ines the rise )elocit. o; an oil particle based

on its densit. and si=e3



A&M A&M University

Texas

#3i&al Petroleum


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2elati)el. ine;;icient

2e-uires largea+ount o; space

Accept a /ide)ariet. and proportions

o; oil and solidsincluding )iscous( stick.

or /ax. oil3http544///3+onroeen)iron+ental3co+4api8clari;iers3ht+

AP #eparator



A&M A&M University

Texas

#3i&al Petroleum


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*he Dissol0ed Air4lotation 2DA43 unitconsist o; t/o sections

First( in the > flocculatorcha+ber? the in;luent is

+ixed /ith coagulantde+ulsi;iers that cause the

agglo+eration o; oildroplets and solids3

*hen the oil./aste ;lo/s into

the flotationsection ( in /hichrising air bubblesadhere to these

particles causingthe+ to rise3



A&M A&M University

Texas

#3i&al Petroleum


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Finall.( in thesur;ace the scu+is re+o)ed b. aski++er and the

settled sludge;ro+ the botto+ is

displaced b.gra)it. orpu+ping3

http544///3h.dro;lotech3co+4site8+ap3ht+



A&M A&M University

Texas

#3i&al Petroleum


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&-ualization Basin *hese are tanks or lined ponds3 According to the

'epart+ent o; 1n)iron+ent ! Natural 2esourceso; $outh 'akota( e-uali=ation basins ha)e t/oob7ecti)es5

///3ba.cod/s3org48about4process3ht+l



A&M A&M University

Texas

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>*he secondar. ob7ecti)e isto da+pen the strength o;

/aste/ater constituents b.blending the /aste/ater in

the e-uali=ation basin to+aintain a degree o;

reliabilit. and operationalcontrol?3

Genesee County ARTP&-ualization Basin

*he pri+ar. ob7ecti)e is toda+pen the )ariationscaused b. in;lo/4in;iltration and the diurnal ;lo/)ariation( to achie)e anearl. constant ;lo/ ratethrough the do/nstrea+treat+ent processes3



A&M A&M University

Texas

#3i&al Petroleum


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*he Acti0ated #ludge Process is one o; the +ost

co++on secondar. treat+ent processes3 *his processuses $aproph.tic bacteria to re+o)e suspended solidsand dissol)ed B%'3

According to Acti)ated $ludge( &anual o; ractice @Water 1n)iron+ent Association( 6 DE( the acti)ated,

sludge process contains ;i)e essential interrelatede-uip+ent co+ponents3



A&M A&M University

Texas

#3i&al Petroleum


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63 An aeration tank in /hich air or ox.gen is

introduced into the s.ste+ to create an aerobicen)iron+ent3 At least se)en +odi;ications in theshape and nu+ber o; tanks exist to produce)ariations in the pattern o; ;lo/3



A&M A&M University

Texas

#3i&al Petroleum


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#3 An aeration source that can be pro)ided b.

pure ox.gen( co+pressed air or +echanicalaeration3

Pi&ture o( adi user usedto su33l# theair needed (orthemi&roorganisms.



A&M A&M University

Texas

#3i&al Petroleum


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"3 Clari;iers3 Acti)ated sludge,solidsare separated ;ro+ thesurrounding /aste/ater b.;locculation and gra)it.sedi+entation3 *hen a thickenedsludge ;locs and ter+ed returnacti)ated sludge or 2A$E is;ounded in the botto+s /hile inthe upper portion o; the clari;ierthe /aste/ater /ith lo/ le)el o;acti)ated,sludge solids insuspension is ;or+ed3



A&M A&M University

Texas

#3i&al Petroleum


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3 *he return acti)ated sludge 2A$E;ro+ the secondar. clari;iers ispu+ped back to the aeration tank toensure the replenishing o; the+icroorganis+s3



A&M A&M University

Texas

#3i&al Petroleum


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3 Finall.( acti)ated sludge containing an

o)erabundance o; +icroorganis+s +ust bere+o)ed( or /asted /aste acti)ated sludge(or WA$E( ;ro+ the s.ste+3

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http://www.water-technology.net/projects/chicago/index.html






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Membrane Separation Techniques em$rane separation ( 2) techni@ues

have e&perienced high growth in recentyears and are widely $eing applied in theindustry today as they are intended to

ul ll the ollowing necessities:'e+and ;or higher -ualit. productsIncreased regulator. pressures*he rising interest in preser)ing naturalresources1n)iron+ental and econo+ic sustainabilit.3



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Among its many strengths, some of the reasons for the increased applicabilityof membrane separation processes are:

Appreciable energ. sa)ings5 Lo/ energ. consu+ption becausethese s.ste+s operate near roo+ te+perature3Clean technolog. /ith operational ease3Co+pact and +odular design using less space than cu+berso+etraditional +ethodsE3roduce high,-ualit. products due to the high selecti)it. o; the+e+branes3

Allo/ the reco)er. o; salable b.,products ;ro+ /aste strea+s(/hich increases their pro;itabilit.3Greater ;lexibilit. in designing s.ste+s31as. incorporation to presentl. existing industrial plants3

ncreasing applicability



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Membrane separation techniquesH 7he $asic o$Nective o mem$rane separation processes is the selective permeation o one or

more species through a mem$rane# there$y achieving separation'

H 8ccording to IDP8C# a mem1rane is a Kstructure# having lateral dimensions much greaterthan its thic ness# through which mass trans er may occur under a variety o driving orces '

H 2ince mem$ranes avoid the ow o li@uid# the transport through the mem$rane is $y:2orption: It re ers either to adsorption or a$sorption o the particles in the mem$rane'+iBusion: 7he movement o particles rom areas o high concentration to areas o lowconcentration' For diBusion to occur# the mem$rane must $e permea$le to molecules

H 7he 3ermea1ilit# descri$es the rate o transport o particles through mem$ranes'

$che+atic representation o; a +e+brane separation unit3

4eed

u+p

Retentate

'em.rane

Permeate

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by-product

Final Product

residueFeed stream 1

Feed stream 2

"p5stream processsection

n5course processsection

Do)n5stream processsection

PR(C&##

Fluid preparation Fluid regeneration( production uri;ication( production reco)er.(e;;luent re)alori=ation

B y-product for sale

K em$rane separation techni@ues can$e applied in diBerent sections o theprocess '

! Membrane Separation "rocesses can differ from one another in the type and configuration ofthe membrane, the mechanism of trans#membrane transport for $arious water solutioncomponents and, the nature of the process dri$ing force%



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(* Mem1rane 3a&:ing densit#8 It de nes the eBective mem$ranearea installed per volume o a module and is the main indicator orthe degree o pretreatment necessary or the diBerent modules inorder to achieve a sa e and trou$le5 ree long term operation'

,here C is the molar concentration o the solute# > is theuniversal gas constant and 7 is the a$solute temperature'

CRT =π

In the case o dilute solutions#

osmotic pressure can $e predictedwith

an’t 4oB’s e@uation:

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em$ranes*he +axi+u+ separation reached in +e+brane processes depends on theper+eabilit. o; the +e+brane ;or the ;eed solution co+ponents3

A permea.le mem.rane allo/s the passage o; all dissol)ed substances and thesol)ent3

A semipermea.le mem.rane is capable o; transporting di;;erent +olecular speciesat di;;erent rates under identical conditions3 *he ideal se+iper+eable +e+brane in+e+brane processes is per+eable to the sol)ent onl. but i+per+eable to allsolutes3&e+brane separation processes depend strongl. on the che+ical nature o; the+e+brane +aterials and the ph.sical structure o; the +e+branes3

*he ;ollo/ing are so+e desirable characteristics o;+e+branes5

Good per+eabilit.High selecti)it.&echanical stabilit.*e+perature stabilit.

Abilit. to /ithstand large pressure di;;erences across+e+brane thickness

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MEM +A E$LASS'4'$A ',

%2IGIN

&A*12IAL

&%2 H%L%G04$*29C*921

MEM +A E

$.nthetic *iological

$olidLi-uid

%rganic Inorganic

Non,porous orous

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%2IGIN

&A*12IAL

&%2 H%L%G04$*29C*921

MEM +A E


$olidLi-uid

%rganic Inorganic

Non,porous orous

!iscriminationaccording to

c emical a8nities

bet$een componentsand membranematerials6

!iscriminationaccording to si9e of

particles or molecules6% e mec anism on$ ic separation isbased is sieving or

"ltrating6 gradient in

4draulic pressure actsas t e driving force6

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%2IGIN

&A*12IAL

&%2 H%L%G04$*29C*921

MEM +A E


$olidLi-uid

%rganic Inorganic

Non,porous orous

Mass transport t roug t ese membranes isdescribed b4 t e solution/di5usion model; asfollo$s:

•2orption of a component out of t e feedmi7ture and solution in t e membrane material6

•%ransport t roug t e membrane along a potential gradient6

•!esorption on t e second side of t emembrane6

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S=MME +'$)H,M, E ,US

*

#onstructed b4 a single material and becauseof t is reason, t e membrane is uniform indensit4 and pore structure t roug out t e

cross/section6

AS=MME +'$

May be either homogeneous orheterogeneous and are characterized by adensity change givenby the membrane material across the cross

sectional area.

$,MP,S' E)HE E+, E ,U

S*

#onstituted b4 di5erent ( eterogeneous)materials, t e membranes ave a t in, densela4er t at serves as t e "ltration barrier6 ut,unlike skinned membranes,

is made of di5erent material t an t e poroussubstructure onto $ ic it is cast6

Skinned type: consist o a dense

s inned layer used as primary ltration$arrier and# a thic and more porousunderstructure that serves as supportstructure'

Graded density type : the porousstructure gradually decreases in

density rom the eed to the ltrateside o the mem$rane'

According tothe PhysicalStructure

(“trans-wallsymmetry”)

7his @ualitydescri$es the level

o uni ormitythroughout the

cross5section o themem$rane'

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MEM +A E PE+4,+MA $E A D

MA' E A $E 7he per ormance o a mem$rane depends on:

7he characteristics o the mem$rane

7he eed solution $eing treated

7he operating conditions

7he ollowing are some parameters used to measure mem$raneper ormance:

+e&over#4a&tor

&''co$(e = Feed

permeate

Q

Qery

< ere = permeate and = >eed are t e permeate ?o$ rate and t e feed ?o$ rate

respectivel46

easures how mucho the eed is

recovered aspermeate'

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+e e&tion or+etention

&'')* −

= Feed

Permeate Feed

C C C

R

< ere # >eed is t e concentration of a particular species in t e feed and # permeate is t e concentration of t e same specie in t e puri"ed stream6

ransmission Percentage o solutethat is not retained $y

the mem$rane'

easure o the ractiono solute that isretained or the

mem$rane'

&''= Feed

permeate

C

C T RT −=&''or

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$on&entration4a&tor

Feed

tentate

C

C CF (e=

ig #>@s are desirable but, t e4 are limited because it results in a igosmotic

pressure ('O, +>) or cake buildup (M>, U>), $ ic leads to t e cost raise6

De&ontamination 4a&tor

Permeate

Feed

C C

DF =

Dse ul to evaluate theper ormance o wastetreatment processes'

easure o the degree oincreasing the

concentration o acomponent'

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em$rane Per ormance can $e aBected or the ollowing phenomena:

Membrane compaction: Is the decrease in mem$rane permea$ilitycaused or the compression o the mem$rane structure under thetransmem$rane pressure'Concentration polarization: is characteri ed or the accumulation oretained species at the mem$rane sur ace' 8s conse@uence# themem$rane sur ace is su$Nected to a eed concentration that is higherthan the concentration o the $ul eed stream which leads to thedevelopment o high osmotic pressures in reverse osmosis andnano ltration' 7he thic ness o this $oundary layer can $e controlledpartially $y the velocity and tur$ulence o the li@uid pumped over themem$rane during the mentioned cross5 ow operation'

8lthough this phenomenon isreversi$le# the ouling it

causes may not $e'

s detrimentalbecause:

It decreases u& and retention and increases the potential

or ouling through $acterial growth or chemical reactionssuch as precipitation'

It causes stagnant and irreversi$ly $ound ca e ormation inmicro ltration'

In ultra ltration# it causes arising osmotic pressure $uild upand possi$le gel ormation'

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ouling: Is the deposition o su$5micrometre particles (smaller than !m) on the mem$rane sur ace and%or its pores' It occurs whenreNected solids are not transported rom the sur ace o the mem$rane$ac to the $ul stream'

In general# there are our maNor types o ouling:

$om3arison o( 4ouled and $lean Mem1rane

.enerall4, t edi5erent t4pes of

fouling occursimultaneousl46

!issolved solids

2uspended solids

+on/biological organics

iological organisms

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+ri$ing orces for TransportH In general# our diBerent driving orces are possi$le in mem$rane transport:

H Each o the driving orces have a counter in uence on the other u&es in addition to their primary eBect' Fore&ample# the pressure gradient can cause a u& o current called the streaming current# $esides the u& o solvent'

D+'>' 4,+$E P+'MA+= E44E$

Pressure Flu& o solvent

Concentration Flu& o solute

Electrical Potential Flu& o electrical current

7emperature Flu& o thermal energy

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According to the Driving Forces for transport ( +e+brane processes

can be classi;ied as ;ollo/s5Pressure Gradient 2P3+

2e)erse os+osis

9ltra;iltration

&icro;iltration

Nano;iltration

apor per+eationGas per+eation

er)aporation

&lectrical potential Gradient 2&3+

1lectrodial.sis

&e+brane electrol.sis

1lectrosorption

1lectro;iltration

1lectroche+ical ion exchange

Concentration gradient 2C3+

'ial.sis

&e+brane extraction$upported li-uid +e+brane $L&E

1+ulsion li-uid +e+brane 1L&E

Non,dispersi)e sol)ent extraction /ithhollo/ ;iber contactors3

Temperature gradient 2T3+

&e+brane distillation

*her+o,os+osis

Pro&esses with &om1ined driving(or&es81lectro,os+o;iltration 1E

1lectro,os+otic concentration 1 CE

Gas separation CE

ie=odial.sis CE

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E&amples o applications and separation processes which

compete with the respective mem$rane separation process'Pro&ess A33li&ations Alternative

Pro&esses

icro ltration 2eparation o $acteria and cells romsolutions

2edimentation#Centri ugation

Dltra ltration 2eparation o proteins and virus#concentration o oil5in5water emulsions Centri ugation

3ano ltration 2eparation o dye and sugar#water so tening

+istillation#Evaporation

>everse Osmosis +esalination o sea and $rac ish water#process water puri cation

+istillation#Evaporation#

+ialysis

+ialysis Puri cation o $lood (arti cial idney) >everseosmosis

Electrodialysis 2eparation o electrolytes romnonelectrolytes Crystalli ation#Precipitation

Pervaporation +ehydration o ethanol and organicsolvents +istillation

as Permeation4ydrogen recovery rom process gas

streams#dehydration and separation o air

8$sorption#8dsorption#

Condensation

em$rane+istillation ,ater puri cation and desalination +istillationPerryGs Chemical EngineersG 4and$oo # =th edition# pages 115/= to 115-<'

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Pressure +riven em$rane

ProcessesPressure driven processes are mature technologies with alarge num$er o success ul applications in industrial water andwastewater treatment'

7heir e&i$ility in process con gurations can optimi e

per ormance' 7hey are suita$le or system integration with conventionaltreatment steps'

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P+,$ESS P,+E S'FE 4LUG)L2m h*

P+ESSU+E)3si*

F "'! to 1 mm !"" Q !"""!0 5 -"DF "'""0 to "'!

mm/" Q /"" !" Q !""

3F "'"""0 to"'""0mm

1" Q !0" 6" Q 1"" psig(<"

typically)

>O R "'0 nm !" 5 /0 1"" Q /""

% e follo$ing table s o$s t e most used ressure !riven ( !)Membrane processes and t eir t4pical operating values:

P+mem$raneprocessesprimarily$ased on

species si e

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"ressure +ri$en Membrane "rocesses

Features o; ressure,'ri)en &e+brane $.ste+s ;or 1n)iron+ental Applications3 21F

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Pressure driven mem$rane processes are specially use ul where a wide range o possi$lecontaminants have to $e removed over the entire removal spectrum i'e' macro particles toionic species' Mem1rane

Pore Si%e) µm*

Pressure)1ar*

2e)erse %s+osis 2%E

9ltra;iltration9FE

Nano;iltrationNFE

&icro;iltration&FE

":, :

#:, :

6,6:

6

6: , ,6: ,"

6: ," ,6: ,#

6: ,# ,6: ,6

6: ,6 ,6: 6

#uspended solids

Bacteria

Viruses

'ulti0alent ions

'ono0alent ions

%ater

Retentate2concentrate3

Permeate2filtrate3

4&&D

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4+ 4+

4+

4+

SP

S P

P

P P

4

M M

M

M

M

7here are several types o ows used in mem$rane5$asedseparations' 7he ollowing are some o them:

)a* &o-&urrent <ow

)d* $ross<ow

)e* Dead-end<ow

)1* $om3letel#-mi!ed <ow

)a* &ounter-&urrent <ow

S em$raneF S FeedP S Permeate> S >etentate2 S 2weep

stream

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n pressure driven processes separation is ac ieved eit er b4 dead/endor cross ?o$ mode:

Dead-end flow mode 8 7he eed ow is perpendicular tothe mem$rane and the only outlet or upstream uid isthrough the mem$rane' In this con guration the ow$om$ards the mem$rane sur ace' It is not a veryrecommended mode $ecause the particles accumulatedon the mem$rane sur ace could cause signi cantpressure drop as it $ecomes plugged or ouled'

Cross flow mode : In this mode the eed streammoves parallel to the mem$rane and the uid on thedownstream side o the mem$rane moves away romthe mem$rane in the direction normal to the mem$ranesur ace' 7his con guration reduces material $uildup onthe mem$ranes $y sweeping the material away rom thesur ace'

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Types of OsmosisThere are two types of Osmosis processes

as shown in ig &%&! Direct Osmosis (DO): +O uses low

pressure% The sol$ent passes through themembrane dri$en by the difference insolute concentrations on the two sides%-quilibrium is reached when sufficientwater has mo$ed to equali.e the soluteconcentration on both sides of themembrane%

! Reverse osmosis (RO): (O uses a high# pressure which is larger than O" on thehigh concentration side% So, the carrier is

preferentially permeated, while the

retentate contains the re/ected solute*contaminant)% Thus, the membranedi$ides the water from the contaminants%The main aim is to purify water and notdilute the contaminants%

!"#$%$&'$#M

π

,smoti&Pressure

7he solvent u& isstopped '

Puresolven

t Solution

Mem1rane

(SM(S$S2olvent passes

the mem$rane tothe solution side'

rom lowsolute

concentrationto high

concentration.

∆ P π

'!)!'S!(SM(S$S

7he u& isreversed when aP greater than π is

applied'

rom highsolute

concentrati on to low

concentrati on

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Permeate

eed

'e*ect

In >everse Osmosis a pump is used to raise the pressure and the eed isdistri$uted among a num$er# n # o modules' 7he reNect is collected and ta enor urther treatment# disposal or sale' 7he permeate is recovered andconstitute the clean stream'

>everse Osmosis can$e used in a legion oapplications' 2ome othem are: seawaterdesalting# treatmento cheese whey#metal nishingsolutions# $leach anddye plant e9uent andwaste water romsewage treatment

wor s'

+everse ,smosisPer(orman&e

ultra;ltration

eva3oration

+everseosmosis

eva3oration

lea&h3lant

eCuent

Sugars IJ)w2v* /ater

(orreuseSugars 7J)w2v*

Sugars K7J)w2v*

Lignosul(onates 67J )w2v*

Lignosul(onates K7J )w2v*

+everse ,smosis (or 3ul3ed 3a3er industr# waste

treatment.

+E>E+SE

,SM,S'S

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+E>E+SE ,SM,S'S

MEM +A E A DM,DULES

H,LL,/ 4' E+

4LA SHEE

U ULA+

According toGeometric

Shape ,membranes

can beclassified in

ollo$ >ibermodule

2piral$oundmodule

late and

>ramemodule

%ubularmodule

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)))*mtrinc*com, Pages,4A6,fa-s*html

S3iral-/ound Module8 Consist o twosemipermea$le mem$ranes placed $acto $ac and separated $y a woven a$ricthat unctions as a permeate carrier#designed to prevent the mem$rane rompenetrating into it and to minimi epermeate pressure drop' 7he threeedges o the mem$rane are sealed withadhesive# while the ourth one isattached to a per orated central tu$e',hen the pac age is rolled up# themem$rane layers are separated $y amesh that not only promotes tur$ulence#improving mass trans er $ut alsoreduces concentration polari ation' 7hespirally wound element is inserted into apressure vessel or module housing'

7hus# the pressuri ed eed water owsa&ially into only one ace o the cylinder'

7he permeate passes through themem$rane and down the permeatecarrier and into the per orated centraltu$e# where it is collected and removed'

7he reNect ows out o the other end othe spiral module'

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Plate and 4rame Module8 Consists o circularmem$ranes sealed to $othsides o a rigid plate(constructed o plastic#porous $erglass orrein orced porous paper)#which acts as mechanicalsupport and as permeatecarrier' 7hese units areplaced in a pressuri edvessel or use' Each platein the vessel is at lowpressure# so that permeatepasses through themem$rane and is collectedin the porous media'

u1ular Module8 Each mem$rane is heldin a porous tu$e' In practise# the eedstream is circulated through tu$es inseries or parallel' Permeate solutionpasses through the mem$rane# throughthe tu$e and drops oB into a receptacleor urther permeate removal'

Tubular Module

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Hollow 4i1er Module )H4+,*8 Consist o a shell which houses avery large num$er o hollowmem$rane $ers' 7hemem$rane $ers are grouped ina $undle# evenly spaced a$out a

central eed distri$utor tu$e'One end o the $er is sealedand the other is open to theatmosphere' 7his $undle isinserted into a pressurecontainer or use'

+uring operation# pressuri edeed water is introduced throughthe distri$utor tu$e which owsaround the outer side o the$ers toward the shell perimeter'

7he permeate penetratesthrough the $er wall into the$are side and is removed at the

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AD>A A ES A D D'SAD>A A ES ,4 MEM +A EM,DULES

2PI>8L5,OD3+

4OLLO, FI*E>

7D*DL8>

PL87E 83+F>8 E

H Low manu acturing costH >elatively easy to clean $y $oth

chemical and hydraulic methods'H 4as a very $road range o

applicationsH 4igh pac ing density

H >elatively low manu acturingcost'

H CompactH 4igh pac ing densityH odes energy re@uirement

H Can $e operated on e&tremelytur$id eed waters'

H >elatively easy to clean eithermechanically or hydraulically'

H Can process high suspended solideed with minimal pretreatment'

H oderate mem$rane sur ace'H ,ell5developed e@uipment'

H It can not $e used on highly tur$ideed waters without e&tensivepretreatment'

H 2uscepti$le to plugging $yparticulates

HE&tremely suscepti$le to oulingdue to very small spacing $etween$ers'

H +i;cult to clean'H >e@uires e&tensive pretreatment'H Limited range o applications'H 4igh capital cost'H >elative high volume re@uired per

unit mem$rane area'

H E&pensive to operate or largescale'

H 2uscepti$le to plugging $yparticulates at ow stagnation

points'H Potentially di;cult to clean'

AD>A A ES D'SAD>A A ES

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+, $al&ulationsH In modeling an >O unit we should consider the ollowing aspects: T em$rane 7ransport: +escri$es the phenomena

ta ing place at the mem$rane sur ace ( waterpermeation# etc')

T 4ydrodynamic model: +escri$es the macroscopictransport# the momentum and energy o the species'H 7he 7wo5+ model# as e&plained $y +r' El54alwagi is used or >O

calculations in this section' 7he method captures the radial anda&ial ows in 4F>O model'

H >O calculations demand that we calculate the ollowing:

a) ,ater u&# 3 water$) 2olute u&# 3 solute

c) Permeate owrate# andd) Permeate Concentration'

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Schematic for 0 (O module

! Adopted from 1"ollution "re$ention Through "rocess ntegration Systematic +esign Tools,2 by +r%-l#0alwagi, fig&&%3, page 455%

2ealing >ing

Feeder

4eed

Permeate

L

1> 2

L2

1>

+e e&t

1r i

1r oA #3i&al

Hollow 4i1er

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Water6"henol Mi7tureH 8s seen earlier or a li@uid5 li@uid mi&ture >O is a good

choice' 7he common eed pressure range is !"5=" atmwith a porous to non5porous mem$rane'

H 7he e@uations used or calculations are as ollows:

+, (verall Material &alance 8

where @ F #@> #@P are volumetric owrates per module oeed# permeate and retentate respectively'

1) 7he volumetric -owrate per module is given $y:

nQ

q F F =

R P F qqq +=

,here UV F’ is the total eed volumetric owrate and U nM is the num$er

o modules'

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/) #omponent Material &alance on solute :

where# C F# CP and C > are the concentrations o solute in theeed# permeate and reNect respectively'

6) ater lu/ :

where#

∆P S Pressure diBerence , π S OP o eed# CF S solute concentration in the eed C 2 S average solute concentration in the shell side# and

8 S solvent permea$ility

γ π

−∆= S

F

F water C

C P A N

( ( "",, CqCqCq +=

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6a) 8nd γ is given $y:

89&''&33%&&5&

i

S o

r x LLr A η µ

η γ +=

θ θ

η tanh

=ii

o

r L

r x

r A 4

&

49&''&33%&

&5

= µ

θ

P R F P

P P P −

+=∆

4

4 R F

S C C

C +

=

,here#

6$) 8lso# the pressure di0erence across the mem$rane is :

where P F #P> #PP are pressures o eed# reNect and permeate'

and

or

6c) 7he concentration o solute in the shell is calculated asollows:

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0) Solute lu/ : 3 solute S solute transport parameter T C 2

-) Permeate lowrate :

where# 2 m is the hollow $er sur ace area per module'

=) Permeate Concentration :

S M

solute C K D

N

=

δ 4

water m P N S q =

water

solute P N

N C =

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H Com$ining these e@uations with e@uation 6) we get the ollowing:

R P F F F C qqC q )* −≈

H Considering most o the solute is retained in the reNect#

e@uation /) can $e simpli ed to:

4ence#

7he last e@uation is a @uadratic e@uation that can $e solved or C > 'Once this is done we can calculate e@uations 6) through =) too$taining the end permeate concentration' I this concentration doesnot satis y the target concentration# new values or parameters suchas n # PF or diBerent system con gurations has to $e proposed'

R F

R F m F F F C C

C P AS qC q

+−∆−= γ π

&4

'44

4 =−

−∆−+ F F R

F m F R

F

F m C qC P AS qC

C AS γ

π γ

π

alid or highly reNectingmem$ranes# when

F F P P C qC q <<

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$,S A AL=S'SA$ Annuali%ed ;!ed &ost o( modules Annuali%ed ;!ed &ost o(

3um3

nnuali9ed "7ed cost of pumps (AB4r)C

0601DEF?o$ rate t roug pump (kgBs)G pressure di5erence across pump

(+Bm H )I 06EJ

nnuali9ed "7ed cost of 'O modules (including annuali9ed installed cost,membrane replacements, labor and maintenance)C

yr ulemod:

!#!6"

Cost o electric powerS "'"- W% , hr

7he mechanical e;ciency o pumps and tur$ines was considered as -0J

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+ESULS ,4 H4+, $AL$ULA ',

VFS1<'1 g%sCFS6='< ppmn ma&S -/ >

P

>

P

>

P

VPS6'"/ g%sCPS/0'<< ppm

VFS10'!= g%sC>S00'-1 ppm8limentaciXn

VFS1<'1 g%sCFS6='< ppm


n ma&S -/


n ma&S -/

*y doing 4>FO calculations many diBerent solutions can $e o$tainded or this pro$lemdepending on the modules con guration and the cost analysis' 7he ollowing gure is onesolution# where the target composition is not achieved'

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>

P

VFS1<'1 g%s

CFS6='< ppmn ma&S -/VFS10'!= g%sC>S00'-1 ppm

>

P

>

P

>

VFS!1'". g%sC>S/0'<< ppm

VFS!'= g%sC>S1='"0 ppm

V>S!"'/. g%sC>S6!'.. ppm

8limentaciXnVFS.='0< g%sCFS6='<0ppm P

VPS6'"/ g%sCPS/0'<< ppm

+ESULS ,4 H4+, $AL$ULA ', 7he ollowing diagram shows another solution to our pro$lem# in this solution the targetcomposition is lower $ut as in the last case# the target composition is not achieved'

any con gurations were tried and no one o them gave satis actory results $ecause thecomposition o the permeate was not the desired'

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, SE+>A ', S A D

+E$,MME DA ', S 4,+ '( $AL$ULA ', S

7he permeate stream should meet two re@uirements:

!) 7he permeate owrate should $e no less than a given owrate:

1) 7he concentration o the undesira$le components in the permeateshould not e&ceed a certain limit generally settled $y an

environmental regulation'

min P P QQ ≥

ma7 P P C C ≤

7he owrate per module is typically $ounded $y manu acturer’sconstraints:

ma7min

F F F qqq ≤≤

7he oregoing e@uations assume that mem$rane per ormance is timeindependent# this means the eBects o reduction in permea$ility are notconsidered'

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PP is typically atmospheric'It is advisa$le to maintain moderate to low eed pressure to avoid theincrease o the costs'

8lso in order to reduce the 78C# the num$er o modules should $e minimumand to get that# the owrate per module must $e ma&imum'

In some cases it is use ul to recover energy rom the retentate (Nust when thevalue o recovered energy is higher that the cost o recovering it)# to do it isnecessary to eed this stream to a tur$ine' In those cases the annuali ed&ed cost o tur$ines must $e added to the 78C:

nnuali9ed "7ed cost of turbines (AB4r)C

06K1LHF?o$ rate t roug turbine (kgBs)G pressure di5erence across turbine(+Bm H )I 06KE

>eed 'eject

ermeate

= >

# >

>

= '

# '

'

=# '

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8mmonia and phenol contents are

high and cyanides which areanions o 8mmonia ma e some othe $iological treatments involvingnitri cation%denitri cationwaste ul 1 '

1 >' arr and ' Moucar# >ecovery o ammonia rom industrial wastewater' nt6 # em6 &ng6 66 /(!<</)# p' 6!-

S EAM S +'PP'

N/h# Steam Stri33ingO

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y

2team 2trippingH 8 wastewater stream is contacted with steam in

a pac ed or trayed tower' 7he com$ined eBectso the steam and heat causes pollutants (phenolsand ammonia) to trans er rom the li@uid to thevapor phase' 7he pollutants are carried out withthe vapour' 7he contacting continues down thetower# ma ing the wastewater leaner in theorganic material while the vapor phase richer inpollutants as it travels up the tower'

7he wastewater is ed at the top o the tower' 7he inNectedsteam at the $ottom o the tower provides the re@uired heatand vapor ow' Clean water leaves as $ottoms while thepollutants leave the top heavily laden with organic material'

7his steam%organic com$ination is condensed and processedlater' 7he principal eature o steam stripping is that acontaminated wastewater and steam are inNected into thetower which results in clean water as the end product'

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y

8spen >8+F>8C*he stea+ stripping processcul+inates to gi)e a clean /aterstrea+ /ith trace a+ounts o;a++onia and phenol strea+#E3 $trea+ contents high

le)els o; phenol and a++oniathat co+e along /ith around# o; the /ater a+ount instrea+ 63 In strea+ " there areno products since thecondenser has a distillation;raction o; =ero3

*he 2A'F2AC ;eature o; Aspenused ;or the si+ulation o;separation process is sho/n inthe ;igure to the right3

B6

6

#

"

F

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y

2team 2tripping with 8spen

#etup and operating specifications

for steam stripping using AspenRAD4RAC

um1er o( stages 67

$ondenser Par&ial->-L

+e1oiler ettle

Valid Phases >-L

em3erature 77 Q4

Pressure 5R. 3sia

Distillate to feed ratio(mole) 0.25

H 8spen simulation was usedor the steam strippingprocess' 7he con gurationor the setup are given inta$le !'!'

H Further# the temperature

used is 1""oF

near $oilingpoint o water and apressure o !6'= psia# closeto atmospheric pressure'

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>E2DL72H Dsing the setup shown in

gure!'! and running the 8spensimulations# resulted in the datarecorded in the ta$le to theright'

H 2tream !:7otal Feed S -<016!'-=l$%hr

H 2tream 1: ,ater S 01!6!/'-1 l$%hr(7race ammonia and Phenol)'H 2tream /: Condenser set to ero# no

condensation'H 2tream 6: ,ater S !=/.1.'! l$%hr

H 2tream 1 has mostly water andphenol concentration o "'!!=ppm complying with CF>regulations# while water5phenol5ammonia separation in stream6 can $e urthered using othersuita$le separation processes'

#TR&A' 7 8 9 :

*e+perature F #:: # #3 #D D ## 3" "

ressure psi 6 3D # 3# 6

apor Frac : : :

&ole Flo/ lb+ol4hr " :3 # #3 6 : D3 6D

&ass Flo/ lb4hr # 63 D #6 6"3 6 : 6D" # 36

olu+e Flo/ cu;t4hr 6#: 63# D # 3" : ": 3"

1nthalp. &&Btu4hr , 3: #D ," 3 "# ,66 3""

&ass Flo/ lb4hr

A&&%N,:6 3""""""" 3 1," : 3"""""

WA*12 6 : #6 6"3 : 6D"D" 3

H1N%,:6 ""3""""""" :3: 666 " : ""3#D##6

&ass Fraction A&&%N,:6 3" 1,: 63# 1," :3:::""

WA*12 :3 6 :3 :3 D"

H1N%,:6 3D 1,: 636D1,:D :3:::6 6

:366D pp+

+esults o( simulation (or water-3henol-ammonia 1# streamstri33ing

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Conclusions! The most suitable separation technique in according to the separation

achie$ed and the cost analysis was steam stripping% "henol is poorlyre/ected by (O membranes so the cost of applying this technique isnot /ustified%

! ;otwithstanding the foregoing, membrane techniques are a good

option since can reach high purity le$els which can be cheaper in longterm%! Some membrane techniques can be combined with con$entional

methods for the treatment of effluents *hybrid processes)%! Con$entional treatment methods as distillation and adsorption and

membrane techniques not studied in this tier as per$aporation or

membrane<based sol$ent e7traction can be used for the remo$al of phenol and ammonia% =u/aws>i and co#wor>ers studied se$eralseparation techniques with this purpose *(emo$al of phenol fromwastwater by different separation techniques)

membarane technic in ro

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