中试规模反渗透出炼厂废水-技术经济和可持续评价

Pilotscalereverseosmosisrefinerywastewatertreatment-a

techno-economicalandsustainabilityassessment

中试规模反渗透出炼厂废水一技术经济和可持续评价

PedroD.A.Bastosctal.DOI:10.1039/d0cw00936a.Environ.Sci.:WaterRes.Tcchnol.

Publishedon27January2021.

Technologiesforwastewaterreclamationandwaterreusewithinoilrefinerieshavebeen

gainingparticularattentionoverthepastdecadeduetolegislativepressuresassociatedwiththe

efficientuseofwaterresourcesandwastewaterdischarge.Havingtoconstantlyrelyonaccessto

greatamountsofwater,theoilandgasindustryhasbeenseekingopportunitiestoreclaimwater

usingsustainableandefficientmanagementprocedures.Inthepresentstudy,anon-sitepilot

planttreatmentstudyonrealrefinerystrippedsourwaterusingreverseosmosiswasconducted

withthegoalofremovingthemainpollutantblockingthepossibilityforwaterreuseinthe

refinerycoolingtower,phenols.Atechnicalandenergyevaluationwasperformedwhere90%of

theinitialwastewaterwasrecoveredwithoutlossofpermeatequalitywith98%rejectionof

phenols.Theinstallationofanenergyrecoverydevicewiththereverseosmosisplantcoulddrop

theenergyinputdemandto1.2kW.hmallowingtheoperatingcoststodecreasefrom1.37€

perm3to0.41€perm3.Treatmentonanindustrialscalewouldallowtherefinerytosaveupto

about375000m3peryearinwateranduptoapproximately417000m3peryearinwastewater

volumedischarged,translatingintonetsavingsofupto286000€peryearandapaybackperiod

ofdownto4years.Thecurrenttreatmentproposedshowedlowcarbonfootprintandnegligible

wastegeneration,basedongreenmetrictools;howevercarefillconsiderationshouldbetakenin

themanagementandtreatmentoftheconcentratestream.

过去十年，由于与有效利用水资源和废水排放相关的立法压力，炼油厂中的废水回收

和水再利用技术受到特别的重视。由于必须始终是来取得大量的水，石油和天然气行业一

直在寻找机会，采用可持续和高效的管理方法回收水。在本研究中，采用反渗透，进行了

实际炼油厂汽提后酸性水的现场中试终止处理研究，目标是去除影响在炼油厂冷却塔中水

回用可能性的污染物苯酚c进行技术和能源评估，其中回收了90%的初始废水，而不影响

渗透液水质，去除98%的苯酚。反渗透装置上安装能量回收装置，可将能量输入需求降至

1.2kW.hm3,从而使影响成本从1.37€7m3降至工业规模处理可是炼油厂每年节

省多达375000m3水，每年可减少多达417000m3的废水量，换算为每年净节省高达

2860006,投资回收期减少到4年。基于绿色度量工具，目前提出的处理方法显示出低碳

足迹和可忽略的废物产生；但是，需要慎重考虑浓水的管理和处置。

Waterimpact水影响

Thepresentpilot-scalestudyfocusesonreverseosmosistotreatwastewaterfromthe

catalyticcrackingcomplexatthelargestPortugueseoilrefinery.A90%recoverywith98%

rejectionofphenolswasachieved,makingihesavingofasignificantamountoffreshindustrial

waterpossible,encouragingsustainablemanagementproceduresfbrindustriesthatconstantly

relyonsubstantialamountsofwaterresources.

本中试规模研究重点是处理葡萄牙最大炼油厂催化裂化装置产生的废水的反渗透。

达到了90%的回收率和98%的苯酚去除率，可以节约大量的工业用新鲜水，促进依靠大

量水资源行业的可持续的管理程序。

1.Introduction引言

Oilrefineryeffluentsareaqueousformsofwastegeneratedfromcrudeoilrefining

processes.Beingcomposedofadiverserangeoftoxiccompounds,suchasoilandgrease,

phenols,sulphidesandammonia,suchfbnnsofwastewaterareamajorsourceofaquatic

pollution.1,2Moreover,oilrefineriesarcconsideredahighlywaterdemandingindustry,relying

onaconstantamountofindustrialwaterthroughouttheyear.Therefore,environmental

regulations,aswellasstrictwastewaterdischargelimitshaveencouragedmanyindustriesto

adoptefficientstrategiesfbreffluenttreatmentandwaterreuse,aimingattheminimizationof

environmentalimpact.Apromisingopportunityfbrwaterreclamationaimsatreusingwaterfbr

coolingtowers,sincetheyareamongthelargestwaterdemandingunitsinthepetroleumindustry.

Legislativepressurestogotheextramilehaveeveninvolvedalong-termgoaloftotal

abolishmentofanyformofwastedischargetowaterreceivingbodiesthroughaconcept

describedaszeroliquiddischarge(ZLD).3

炼油厂废水是原油炼制工艺产生的水形态废物。含各种有毒化合物组成，如油和脂、

苯酚、硫化物和氨，这种形态的废水是水生污染的主要来源。另外，认为炼油厂是高度需

水的行业，全年依靠恒定量的工业用水。因此，环境法规以及严格的废水排放限制促进很

多行业采取有效策略，除了金额回用废水，目的是最大程度地减少环境影响。由于是石油

工业的最大用水设备之一，水再生水的具有前景的机会的目标是会回用于冷却塔。进一步

的立法压力甚至涉及一个长期目标，即通过描述为零液体排放(ZLD)的概念，彻底消除

任何形态的废物排入受纳水体。

Amongtheseveralpollutantsthatarccontrolledinthewastewatergeneratedatthelargest

Portugueseoilrefinery,locatedinSines,phenolshaverecentlybeengivenmoreattention.The

presenceofaheavyorganicloadofphenoliccompoundsatitsmajorsourceoforigininthe

refinery,strippedsourwaterfromthecrackingcomplex,iscurrentlyblockingtheopportunityfbr

waterreuseinthecoolingtowers,andlimitsitsuseaswashwaterfordesalters,tominimize

phenolicimpactintherefinery'spre-treatmentwastewatercircuit.Phenolsplayakeyrolein

environmentalimpact,beingamongthemajorhazardouspollutantsinindustrialwastewater

resultingfromtheirpoorbiodegradability,hightoxiciiyandsignificantcontributiontohigh

chemicaloxygendemands.4-6Phenolshavebeenreportedinrefinerywastewaterinawide

rangeofconcentrations(6-500mgL')5andspecificallyinstrippedsourwater(190-537ppm)

fromcrackingcomplexes.7-9Mostrefineriesreusestrippedsourwateraswashwaterfbr

desalters,usingawell-knownandreportedprocedure,?wheremostofthephenolsareadsorbed

intothecrudephase,redirectingthembackintotherefiningprocess,andthus,loweringtheir

contentinthewastewater.Althoughthisformofreusehasprovedtobeastraightforward,

costcffcctivcandrelativelyefficientwayofovercomingphenolicimpactintheeffluent,it

doesn'ttakeintoaccountpossiblefluctuationsinthetypeoramountofphenolsthatareformed

incatalyticcrackingprocessesandthatarenotremovedfromsourwaterstrippingunits.10,11

Moreover,desaltereffluenttreatmentfbrrecyclinginvolveschallengesonitsownalready,with

itsgeneralapproachfocusingmoreonde-oilingandde-mineralizing.12,13

在受控的葡萄牙最大的炼油厂(位于Sines)产生废水的几种污染物中，最近更加重视

苯酚。在炼油厂主要来源，酚类化合物有机物有机负荷高，裂化装置中的汽提后酸性水目

前阻碍冷却塔中水回用的机会，限制其作为脱盐器的冲洗水利用，需要最大程度降低苯酚

对炼油厂预-处理废水回路的影响。苯酚具有重要的环境影响作用，是工艺废水中主要的有

害污染物，这是由于其生物降解性差、毒性强和造成高化学需氧量。报告了炼油废水中不

同浓度范围的苯酚(6-500mgL-1),特别是裂化装置的汽提后酸性水(190-537ppm)。多

数炼油厂采用众所周知和摆个的程序，将汽提后酸性作为脱盐器冲洗水再利用，其中大多

数酚由原油相吸收，回到炼油工艺，从而降低废水中含量。尽管已经证明这种再利用形式

是克服废水中酚类影响的直接、成本效率高且较为有效的方法，但是，未考虑催化裂化过

程中形成的不能由酸性水汽提装置去除的苯酚种类或数量的可能波动。另外，脱盐废水回

收利用处理本身已面临挑战，常用的方法重点是除油和除盐。

Manytechnologieshavebeenreviewedforphenolremovalfromdifferenttypesof

wastewateroverthepastfewyears.5,6,14,15Membraneseparationtechnologieshavebeen

highlightedduetolowenergyconsumption,andeasyscaleupbymembranemodules,leadingto

convenientoperationprocedures.16,17Reverseosmosis(RO),fbrexample,hasbeenfrequently

usedaiwaterreclamationplantsfbrcaseswherehighpuritywaterisrequired,suchasinboiler

feedwatersystems,reportedtoremove99%ofthedissolvedminerals18andupto95%phenols

fromwastewater.19,20ROhasalsobeenrecentlystudiedfbrwaterreuseincoalseamgas

associatedwater,focusingontheimprovementoftheeconomicsinvolved.21Despitethe

advancesinimprovingpumpefficienciesandenergycosts,highenergydemandremainsa

drawbackinROprocesses,withelectricityaccountingfbratleast35%ofthetotaloperating

costsinseawaterdesalinationsystems.22Therefore,determiningtheenergyconsumedinany

ROtreatmentisofmajorimportance,includingrefinerywastewatertreatment,toensureaproper

insightregardingitseconomicfeasibility.Thelastpublishedstudyofrefinerystrippedsour

treatmentthroughROfbeusedontheremovalofaparticularlyrelevantpollutantattherefinery

athand,selenium,withsomepre-treatmentstepsbeinginvolved.9Thepresentstudyfbcuscson

theremovalofphenols,apollutantwhichhasbeenthereasonbehindtheblockingofthereuseof

strippedsourwaterwithinrefineriesthatcontaincatalyticcrackingcomplexes,themainemitter

ofphenols.Atechnicalandenergyevaluationwasperformedfbron-sitestrippedsourwater

treatmentthroughstand-aloneRO,atapilotscale.Thepilotplantresultswerethebasisofan

economicandsustainabilityevaluationintheprojectiontoanindustrialscaleandthepotentialto

recoverenergywasevaluatedbasedonreportedenergyrecoveringmethodsandthespecific

physico-chemicalnatureoftheeffluentstudied.

过去儿年，综述了很多去除不同类型废水中苯酚的技术。由于能耗低且易于通过膜模

块件放大，使得操作程序便利，膜分离技术先显得突出。例如，在需要高纯水是，在锅炉

给水系统中，水回收利用装置经常采用反渗透(RO),报告了去除废水中99%的溶解矿物、

高达95%的酚。最近也研究煤层气伴生水中水再利用RO,重点是提高相应的经济性。尽

管取得改进泵效和能源成本的进展，但是，能源需求高仍然是反渗透工艺的一个缺是，电

力至少占海水淡化系统总运行成本的35%。因此，为保证正确认识经济可行性，确定任何

RO处理的能耗特别重要，包括炼油厂废水处理。最近发表的通过通过RO处理炼厂汽提

后酸性水研究的重点是去除现有特别关注污染物碎，采用一些预处理步骤。本研究的重点

是去除一种污染物苯酚，是影响汽提后选择水在包括催化裂化装置的炼油厂再利用的原因,

催化裂化装置是苯酚的主要排放源。通过中试规模的独立RO现场处理汽提后酸性水，进

行了技术和能源评估。中试装置的结果作为工业规模预测中经济性和可持续性评估的基础,

也根据报告的能量回收方法和研究废水的特定理化性质，评估了回收能量的潜力。

2.Materialsandmethods材料和方法

2.1Pilotscaleexperimentalsetup中试规模实验装置

ToassessthetechnicalperformanceoftheROmembraneatapilotscalefbrrefinery

strippedsourwatertreatment,amembranefiltrationexperimentwassetupasshowninFig.1.

Thephenomenaoffluiddynamicscontrolplayamajorroleinaspiral-woundmodule

configuration,whichmatchtheconditionsatanindustrialscale.Thepilotunitwasequipped

withapermeateandfeedtank,ahigh-pressurediaphragmpump(Hydra-Cell,Wanner

Engineering,Inc.)andavalvetoregulatepressure.Thepilotassayswereperformedin

concentrationmodewheretheconcentratestreamwasrecirculatedbacktothefeedtank,while

penneatingthetreatedwaterintoacleantank.Inordertocalculatetheenergyconsumptionof

thepilotinstallation,a324PlusTrueRMSClampMeter(FLUKECORPORATION)wasusedto

measurethevoltageandcurrentduringthefiltration,allowinginstantaneousandaccumulated

measurements.Theelectricalreadingswerethenconvertedtopumppower(kW)andtranslated

intoenergyconsumption(kW.h)

consideringthetotaldurationof

eachassay.23Thedataobtained

wereusedtoestimatetheaverage

energyconsumptionintreating1

m3ofstrippedsourwater.

Fig.1Schematicrepresentationofthereverseosmosispilotunitcoupledtoanenergy

measuringdevice.配有能量测■设备的反渗透中试装置示意图

为了评估中试规模R0膜处理炼厂汽提后酸性水的技术性能，进行了膜过滤实验，如

图1所示。流体动力学控制现象在螺旋缠绕组件配置中起到重要作用，配置符合工业规模

条件。中试装置配有•渗透液和进液罐、高压隔膜泵和压力调节阀。中试评估以浓缩模式进

行,其中浓缩流再循环回到进液罐,处理后的水渗透到净化罐中°为了计算中试装置的能

耗，使用了324PlusTrueRMSClamp表测量过滤过程中的电压和电流，可进行瞬时和累积

测量。然后将电读数转换为泵功率(kW),考虑到每一种评估的总持续时间，转换为能耗

(kW.h)o取得的数据用计算处理1n?汽提后酸性水的平均能耗。

2.2Membraneandchemicals膜和化学药剂

Apolyamidethin-filmcompositespiral-woundFILMTECSW30-2540reverseosmosis

membraneelementwasusedforthefiltrationassays.Themembranehasanactiveareaof2.8m2,

astabilizedsaltrejectionof99.4%,amaximumoperatingtemperatureandpressureof45℃and

69bar,respectivelyandapHrangeof2-11.P3-ultrasil®73(Ecolab,Lenntech)wasusedfbr

membranechemicalcleaningafterthereverseosmosisfiltrationexperiments.Thismembrane

integratesthefeaturesthatprovedtobethemostappropriateandefficientfbrphenolretention

fbrthewastewaterstudied,asconcludedfrompreliminarylaboratorystudies.24Although

brackishwatermembranesmayleadtohigherpermeatefluxes,thelaboratorystudies,wherea

BW30reverseosmosismembranewasused,showedan80%phenolrejection,generating

penneatesunsuitabletobereused,basedonthewaterreusequalitystandards.

过滤评估采用聚酰胺薄膜复合螺旋缠绕FILMTECSW30-2540反渗透膜元件。膜的有

效面积为2.8m2,稳定的脱盐率为99.4%,最高工作温度和最高压力分别为45℃和69bar,

pH范围为271。在反渗透过滤实验后，采用P3-ultrasil®73化学清洗膜。初步实验室研究

得出的结论，证明这种膜具有综合了最适合和最有效地去除研究废水苯酚的特征。尽管咸

水膜可能达到更高的渗透通量，但是，采用BW30反渗透的实验室研究表明，笨酚去除率

为80%,根据水再利用水质标准，产生的渗透液不适合再利用。

2.3Refinerywastewaterandreverseosmosispilotassays

Twobatchesofstrippedsourwaterwereconsecutivelycollectedfromtheeffluentofthe

sourwaterstrippingunitofthecrackingcomplex,attheSinesrefinery.Whilethelaboratory

studics24allowedtheassessmentofmembranetreatmentperformanceovera6-month

representativeoperationalperiod,thepilotscalestudiesinvolvedanenergyconsumption

evaluationuponoperatingaidifferenttransmembranepressures.Therefore,toavoidfeedquality

variations,thebatchesweresuccessivelywithdrawnandprocessedfbrtreatment.

从炼厂酸性是汽提装置出水连续收集了两批汽提后酸水。6个月代表性运行阶段的实

验室研究可评估膜处理性能，中试规模研究要评估以不同跨膜压力下运行的能耗。因此，

为避免进水水质变化，依次抽出不同批次的水，进行处理。

Samplesfromtheinitialwastewaterandpermeatesobtainedafterreverseosmosiswere

analysedbystandardmethodsfbroilandgreaseandphenolsconcentration(SMEWW5520C/F

andSMEWW5530D,respectively).CODwasanalysedusingtheLCI500cuvettekit(Hach,

Germany)inagreementv/ithISO15705.Ammoniumandsulphidesconcentrationwere

determinedusingtheLCK304andLCK653cuvettetest,respectively(Hach,Germany).Total

dissolvedsolids(TDS)andconductivitymeasurementswereobtainedbymeansofaWTW

portableconductivitymeter.Table1showsthephysico-chemicalcharacterizationofihefeed

batch.

采用标准方法，分析初始废水和反渗透后取得的渗透液水样的油和脂、苯酚浓度。采

用LCI500比色皿试剂盒,分析COD,与ISO15705一致。分别采用LCK304和LCK653

比色皿检测，检测铉和硫化物浓度。总溶解固体(TDS)和电导率检测值采用WTW便携

式电导率仪取得。表1显示进液批次的理化性质。

Table1Refinerywastewatercharacterizationforpilotscaletreatment中试规模储量炼油

厂废水分析

Strippedsourwatercharacterization汽提后酸性水分析

Parameter参数

pH7.2

TDS(ppm)74

Conductivity电导率(piScm」)122.1

COD(mg0?perL)1179

Phenols苯酚(ppm)257

Polar极性O&G(ppm)38

Non-polar非极性O&G(ppm)179

Total总O&G(ppm)217

Ammonium铉(ppm)23

Sulphides硫化物(ppm)0.18

Beforetheexperiment,themembranewasrinsedandcompactedwithtapwaterat51±1bar

fbrabout2huntilconstantpermeabilitywasachieved.Thehydraulicpermeabilityofthespiral

woundreverseosmosismembranewasmeasuredbeforethefiltrationassayataround21℃.

实验之前，膜采用51±1bar的自来水冲洗和压实约2h,直到达到恒定的渗透率。在

约21。(2下的过滤平均之间，测量螺旋缠绕式反渗透膜的水力渗透率。

Theperformanceofthereverseosmosisfiltrationwasdeterminedbymeasuringthe

permeatefluxthroughoutthefiltrationtimeandcollectinginstantpermeatesamplesatdifferent

volumeconcentrationfactors,fbrchemicalanalysis.Thewastewaterwasconcentrateduntilthe

instantaneouspenneatesstartedtolosechemicalqualityregardingwaterreusestandards.The

firstandsecondfiltrationassayswereperformedinconcentrationmodeataconstant

transmembranepressureof50±lbarand35±1bar,respectively,andafeedflowrateofaround

420Lh1.Forpilotplantstudies,operationunderconcentrationmodeisapracticalalternativeto

continuousoperationwithadefinedrecoveryrate,withtheadvantageofrequiringlowerfeed

volumes.Avolumereductionfactorof10correspondstoa90%permeaterecovery,whichis

consideredaratherambitioustargetandusuallyrequiresmultiplestagestoachieveratherthanin

asinglestep.Sometemperaturevariationsoccurredthroughouttheassays,astheywerecarried

outoutdoors.Thetemperatureofthefeedwascontinuouslymeasuredovertimeuntiltheendof

theexperiment.Thepermeatefluxescalculatedfbrbothassayswerecorrectedforareference

temperatureof22℃.ApparentrejectionsofphenolsandCODwerecalculatedusingcqn(1),

通过测量整个过滤时间的渗透通量，收集不同体积浓度倍数的瞬时渗透液水样化学分

析，确定反渗透过滤的性能。废水浓缩到瞬时渗透液化学质量开始降低的不符合水再利用

标准。第一次和第二次过潴评价以浓缩模式进行，跨膜压力分别为50±1bar和35土1bar,

进液流量约为420LhL中试装置研究以浓缩模式运行可连续运行的可行替代方案，具有

明确的回收率，具有所需进液量低的优点。10倍的体积削减锈对应90%的渗透液回收率

回收，认为是一个相当激进的目标，通常需要多个阶段实现，而不是一个步骤。由于在室

外进行，整个评价过程中出现一些温度变化。在实验结束之前，连续检测不同时间的进液

温度。两种评价的计算渗透通量均修正在22%：的基准温度。采用式(1)计算苯酚和COD

的表观去除率，

Apparentrejection(%)=(1-匐TOO(1)

whereCpandCfaretheconcentrationofthepollutantinthepermeateandfeed,

respectively.

其中Cp和Cf分别是渗透液和进液中污染物浓度。

2.4Economicstudyevaluation经济研究评估

Anaverageof50m3h",ofstrippedsourwaterfromthecrackingcomplexattheSines

refineryisgeneratedandsentaswashwatertothedesalters.Thestreamthenundergoesaseries

ofpre-treatmentstepsuntilafinalaccumulatedeffluent,averaging350m3h_1basedon2017-

2019data,isdischargedtotheexternalwastewatertreatmentplant(WWTP).Thismeansthatthe

key-eflluentofthisprojectrepresentsabout14%ofthetotalwastewaterdischarged.Therefore,

aneconomicevaluationwhichfocusesonvolumereductionaswellasthereductionoffresh

make-upwaterdemandforthecoolingtowerisessentialtodeterminetheeconomicfeasibilityof

thetechnologyproposed.

Sines炼油厂的裂化装置平均产生50n?h/汽提后酸性水，作为冲洗水进入脱盐器。

之后水流经过一系列预处理步骤，根据2017〜2019年数据，最终废水平均为350m3hl排

入外部废水处理厂(WWTP)。这意味着这一项目的主要废水约占废水排放总量的14%。

因此，经济评估的重点是水矿削减和冷却塔新鲜补充水需求减少，这对于确定提出技术的

经济可行性至关重要。

Aneconomicevaluationoftreating1200m3perday(50n?h24hperday)ofstripped

sourwaterbyreverseosmosiswasperformed.Thecalculationswerebasedonadirectprojection

ofthepilotplantdataobtainedontoanindustrialROtreatmentunit,consideringanoverall90%

recoveryrate,thereforegenerating1080m3perdayofpermeate.Bearinginmindthatenergy

consumptioninROistypicallythemajorcontributorofoperatingcosts,differentscenarioswere

studied,extrapolatingdifTerentenergydemandsbasedonthepossibleenergyrecoveredthrough

anenergyrecoverydevice(ERD)andtherealdataobtainedinthepilotplantassays.Recent

studiesgointodetailregardingtechnicalefficienciesofERDsinlargedesalinationplants,from

turbinestopressureexchangerswhichhavereportedyieldsofupto90%,reducingspecific

energyconsumptionsdownto3-4kW.hm3.25-27Aselectricitygenerallyaccountsfbrthe

largestportionoftheoperatingcostsofaROplant,difTerentenergyrecoveryscenariosallowa

sensitivityanalysisregardingtotaloperatingexpensesasanaddedinsightforeconomic

evaluation.AsensitivityanalysisrelatedtothefrequencyoftheROunitshutdownsfbr

membranecleaningandmaintenancewasalsoconducted,whichallowsanoverviewofthe

economicassessmentfbrcaseswherechangesintherefiningprocessupstreammightleadto

wastewaterfeedvariations.Thefinaloperatingandcapitalcostsweredirectlycomparedwiththe

savingsinfreshwaterandthereductionofthevolumedischargedperyear,inordertoevaluate

theeconomicfeasibilityofthetreatment.Finally,anenvironmentalandsustainabilityassessment

wasconductedthroughanalysisofrelevantparameters,suchasglobalwarmingpotential,

ecotoxicitypotentialandimpactofwatersaving.

进行了反渗透每天处理1200n?(50m^h1,每天24h)汽提后酸性水的经济评估。计

算是基于取得的中试追查数据直接用于工业反渗透处理装置的直接测算，考虑90%的总回

收率，相应的每天产渗透水为1080n?。考虑到RO中的能耗通常是运行成本的主要来源，

因此，研究了不同的方案，基于采用能量回收装置(ERD)可能回收的能量和中试装置评

估取得的实际数据，推算不同的能源需求。最近详细研究了大型脱机装置的ERD技术效

率，从涡轮机到压力交换器，报告了产率高达90%,单位能耗降低至3-4kW.hm-3。由于

电力通常占RO装置运行成本的最大部分，因此，不同的能源回收方案可用于总运行费用

的敏感性分析，从而更加深入认识经济评估。也分析了与膜清洗和维护关闭反渗透装置频

次相关的敏感性分析，从而可以对上游炼油工艺变化可能导致废水进水变化情况进行全面

经济评估。最终运行和投资成本直接与每年节省新鲜水和排放量减少对比，从而评估肿

着处理的经济可行性。最后，通过分析相关参数，如全球变暖势、生态毒性可能性和节水

的影响，进行了环境和可持续性评价。

3.Resultsanddiscussion结果和讨论

Strippedsourwaterfromthecrackingcomplex,attheSinesrefinery,iscurrentlysubjected

toasequenceofpre-treatmentsteps,todiminishthephenoliclevelsbeforethefinaleffluentis

senttoamunicipalWWTP(wastewatertreatmentplant).Fig.2showsthecurrentroutetakenby

thewastewaterstreamandanalternativeroutethroughmembranetreatment,atthesourceof

phenolicemission.Suchproposedtechnologyresultsfromthemotivationofbothreducingthe

volumedischargedtotheWWTPandsavingwaterthroughreclamationasmake-upwaterin

这种技术的动机是减少排入WWTP的水量和通过回收利用作为冷却塔充水节约用水。

Fig.2Schematicrepresentationofthewastewaterroutetakenbystrippedsourwaterfrom

thecrackingcomplexattheSinesrefinervandthealternativemembranetreatment.采用

的炼油厂裂解装置汽提后金性水废水路径和替代膜处理示意

3.1PerformanceofpilotscaleROfiltration-permeatefluxesandrejections中试规模RO

过滤的性能一渗透通量和去除率

Afirstbatchof600Lofstrippedsourwaterwasprocessedinconcentrationmode,

operatingatthehighestvolumeconcentrationfactorpossible.Thisallowsatechnicalevaluation

oftheprocess,whileavoidingthegenerationofalargevolumeofconcentrate,whichneedstobe

adequatelydisposed.Thewastewaterwasprocessedat50baruntilafinalconcentratevolumeof

52L,leadingtoanapproximatevolumeconcentrationfactorof11.5.Thesecondbatchof400L

wasidenticallyprocessed,butatatransmembranepressureof35bar.Thefinalconcentrate

volumewasapproximately95L,reachingavolumeconcentrationfactorof4.2.

以浓缩模式处理第一批600L汽提后酸性水，以可能的最高体积浓缩倍数运行。这样

可进行工艺技术评估，同时避免产生大量需要适当处置的浓缩液。废水在50bar下处理，

直到最终浓缩液体积为52L,导致大约11.5的体积浓缩倍数。同样处理第二批400L,但

跨膜压力为35bar。最终浓缩液体积约95L,达到4.2的体积浓缩倍数。

Fig.3showstheprofileofthenormalizedpermeatefluxesobtainedasafunctionofthe

volumeconcentrationfactor(VCF).Itispossibletoobservethatwhileoperatingat35bar,the

fluxdeclineissignificantlylowerthroughoutfiltrationthanthepermeatefluxintheexperiment

operatingatatransmembranepressure(TMP)of50bar.AtaVCFof2,anapproximate20%

dropfromtheinitialfluxwasfeltatTMP=50bar,whereasonlya5%dropwasfeltatTMP=35

bar.Thiscouldbegenerallyattributedtomembranefbukngbeinglesssevereatmilderoperating

pressures.Highertransmembranepressuresgenerategreaterpermeatefluxes,butalsopush

fbulantsstronglytowardsthemembranesurface,leadingtoamoreextensiveandfaster

adsorptiononthemembraneand,ultimately,tofluxdeclinethroughoutfiltration.Itcanalsobe

observedthatthepermeatefluxremainedpracticallyconstantfromVCF=2toVCF=10,with

permeatefluxdeclinesrangingfrom2to6%.Anoverallfluxdeclineofaround47%wasfelt,at

aconcentrationfactorof10,Thismeansthatbythetimethefluxhaddroppedbyalmosthalf,90%

oftheinitialfeedwastewatervolumehadalreadybeenconvertedintocleanpermeate.Thisis

duetotherelativelyhighpermeatefluxesencountered(upto44Lh1m2),whichhasonlybeen

foundtobereportedinstudieswithalooserROmembraneandlowersaltrejections,afterUF

treatment,inasimilarphenolicindustrial

wastewater.19Aswasobservedinprevious

labstudies,24thelowosmoticpressureof

thefeedplaysthemostdecisiveroleinthe

highpermeatefluxobtainedinthepresent

pilotstudy,duetolowconductivityresultingfromthelackofsaltswithaveragereported

salinitiesmeasuringdownto113mgL1andconductivitiesnogreaterthan335gScm

Fig.3Normalizedpermeatefluxesatthepilotscaleasafunctionofthevolume

concentrationfactor.中试装置的归一位渗透通量随体积浓缩倍数的变化

图3表示取得归一化渗透通量随体积浓缩倍数（VCF）变化的曲线。可以看出，以35

bar的压力下运行，整个过滤过程中的通量下降要比以50bar跨膜压力下运行的实验运行

低得多。VCF为2时，TMP=50bar时比初始通量大约下降约20%,在TMPW5bar时只

有5%的下降。这通常可以归因于较低压力下运行的膜污染不那么严重。较高的跨膜压力

达到较大的渗透通量，也将污染强压到膜表面，从而导致膜上更全面、更快地吸附，最终

导致整个过滤过程中通量下降。也可以看出，从VCF=2到VCF=10,渗透通量实际上温度，

渗透通量下降范围为2%至6%。浓缩倍数为10时，总通量下降了约47%。这意味着这是

通量下降了近一半，90%的初始进水量已转化为净化的渗透液。这是由于出现了相对较高

的渗透通量（高达44Lh/m-2）,只是在类似的含酚工业废水的UF后采用松散RO膜和低

盐去除率的研窕中报告了这种情况。与之前实验室研究中观察到的一样，进液低渗透压对

本试验研究中取得的高渗透通量具有决定性的作用。这是由于低盐导致低电导率低的，报

告含盐量检测值低至113mgL/，电导率不大于3352cmL

Thegoaloftestingthesystematatransmembranepressureof35barwastoevaluatethe

impactonenergyconsumption,aslowerconsumptionswoulddecreaseoperationalcostsrelated

toelectricity,atanindustrialscale.AspreviouslymentionedintheMaterialsandmethods

section,thevoltagesandcurrentswerecontinuouslymeasuredthroughoutthefiltration.The

instantaneousandaccumulatedvaluesthatwererecordedwereactuallynotlowerthan

thoseobtainedwhileoperatingat50bar.Therefore,gainsrelatedtoenergysavingsceasedto

existwhenoperatingatthelowerTMPandthus,itwasdecidednottoconcentratethe

wastewateranyfurtherthanaVCFof4.2,matchingthetotalfiltrationtimesfbrbothassays.

由于工业规模的较低能耗将降低与电力相关的运行成本，35bar跨膜压力下试验系统

的目的是评估对能耗的影响。如同之前“材料和方法”部分所述，整个过滤过程中连续测量

电压和电流。实际上，记录的瞬时值和累积值实际上不低于以50bar下运行时取得的瞬时

值和累积值。因此，以较低的TMP下运行时，与节能相关的收益就不复存在了，因此,

决定浓缩废水VCF不超过4.2,这与两种测定的总过滤时间匹配。

Fig.4showsthemembraneperformanceregardingapparentrejectionofphenolsandCOD

fbrbothassays,alongwiththecorrespondingpermeatefluxesasafiinctionoftheVCF.High

rejectionsofphenolsandCODwereobtained(approximately97.5%and98%,respectively

ataVCFof3)withphenolrejectionsremaininghighthroughouttheentireassayuptoaVCFof

10(>92%).AslightlossofrejectionstartedtotakeplaceataVCFof6(2.5%dropinrejection)

anda4%dropataVCFof10.RegardingCOD,asimilarbehaviourwaswitnessedwithinstant

rejectionsremainingover94%evenafter90%ofthewastewaterwasfiltered.AtaVCFof10.3,

thepermeatestartedtolosequalityregardingCODvalues,accordingtothequalitystandardsfor

waterreuse(COD<75mgO2perL).3Regardingtherecoveryobtained,itcanbeseenthatthe

feedwasconcentrateduntilaVCFof10,whichcorrespondstoa90%permeaterecoveryrate