环境工程专业外语

Electrocoagulation as a tertiary treatment for paper mill wastewater:Removal of non-biodegradable organic pollution and arsenic

Salim Zodi a ,Jean-No?l Louvet a ,Clémence Michon b ,Olivier Potier a ,Marie-No?lle Pons a ,?,Fran?ois Lapicque a ,Jean-Pierre Leclerc a

a Laboratoire Réactions et Génie des Procédés (LRGP),UPR 3349CNRS Nancy Université,ENSIC,1rue Grandville,BP 20451,54001Nancy Cedex,France b

Norske Skog Golbey SAS,Route Jean Charles Pellerin,88190Golbey,France

a r t i c l e i n f o Article history:

Received 13March 2011

Received in revised form 26June 2011Accepted 1July 2011

Available online 22July 2011Keywords:Arsenic

Electrocoagulation Fluorescence

Organic pollution Paper mill ef?uent

a b s t r a c t

The tertiary treatment of paper mill wastewaters was investigated by testing the effect of batch electro-coagulation for 90min with two parallel iron or aluminum plates at two values of the current density (100and 150A/m 2).Dissolved organic carbon removal ranged between 24%and 46%,and chemical oxy-gen demand removal ranged between 32%and 68%.UV–visible spectroscopy showed a reduction of the aromaticity of the treated ef?uent.The process was also very ef?cient for the removal of lignin-based pol-lution,characterized by the ?uorescence of humic substances.Arsenic was selected as an example of a non-organic micropollutant and was also satisfactorily removed (from 4to 0.5l g/L).The settling charac-teristics of the sludge obtained after the electrocoagulation treatment were also evaluated.The sludge aptitude to settling is better with Fe electrodes than with Al electrodes.The experimental results obtained in the present study indicate that electrocoagulation treatment can be very effective and was capable of improving the paper mill wastewaters’quality downstream of the biological treatment.

ó2011Elsevier B.V.All rights reserved.

1.Introduction

Paper mills produce wastewaters that are the source of impor-tant pollution problems that need an urgent solution [1,2].Each pulp and paper mill consumes a large amount of water ranging from 5to 300m 3per ton of pulp products,while the average sized mill generates ef?uents of about 2000m 3per day.Among the var-ious operations in the pulp and paper industry,the most signi?cant sources of pollution are wood preparation,pulping,pulp washing,bleaching and paper machine operations.Paper mill ef?uents are characterized by high levels of chemical oxygen demand (COD)and total organic carbon (TOC).They also contain various micro-pollutants including organic substances (phenols,chloro-organics,optical brighteners,dyestuffs),heavy metals (cadmium,zinc,etc.)and metalloids (arsenic)in addition to bleaching agents [3–6].According to the French National Registry of Industrial Pollutants [7]30%of the industrial pollution discharged to surface water in France is from the wood,pulp and paper industries.These indus-tries contribute 13%,10%and 4%of the manganese,cadmium and arsenic discharged respectively (average values for the 2003–2008period).If the wastewater is not treated before direct disposal into the river,the resulting effects on the environment are slime growth,thermal impact,scum formation and color prob-lems that can kill ?sh [8],as well as profoundly affect the overall ecosystem.

Wastewater discharged from the pulping,bleaching and chem-ical recovery sections contains lignin,and its derivatives that are the main source of the ef?uent color [9,10].These wastewater components cannot be degraded easily by natural processes be-cause of the strong covalent bonds in their molecular structures [11].Thus,the presence of strongly toxic species,e.g.,heavy metals and metalloids,or dif?cult to degrade species,e.g.,lignin,affects not only the wastewaters’COD levels but renders their disposal very problematic.

Arsenic contamination of water occurs by natural processes and from industrial discharge [12].Arsenic (As)is widely encountered in the earth’s crust with valency values of à3(arsenide),0,+3(As(III)or arsenite)and +5(As(V)or arsenate).In free-?owing water,it is mostly present as arsenate,but in anaerobic conditions,arsenite can be predominant.Arsenic is a poisonous substance which is usually present in natural waters at concentrations less than 1–2l g/L [13].But in many countries such Bangladesh [14],India [15]or USA [16–18]higher concentrations are observed.The World Health Organization has set a guideline value for drink-ing water production of 10l g/L [13].In regions such as the Vosges mountains near Nancy,the discharge of arsenic by industrial activ-ities (mining,pulp and paper)can increase the risk of arsenic con-tamination.This is the case in the upper part of the Moselle watershed where surface water is used for production of drinking

1383-5866/$-see front matter ó2011Elsevier B.V.All rights reserved.doi:10.1016/j.seppur.2011.07.002

Corresponding author.Tel.:+33(0)383175277;fax:+33(0)383322975.

E-mail address:Marie-Noelle.Pons@ensic.inpl-nancy.fr (M.-N.Pons).

water for several communities[19].The arsenic contained in pulp and paper mill ef?uents comes from the wood and the recycled pa-per used as raw materials and from groundwater/surface water used largely in the pulping processes[20].

Several methods have been considered for the removal of pollu-tion and color from the pulp and paper mill ef?uents.The main treatment processes are primary clari?cation by sedimentation or ?otation and secondary treatment by activated sludge or anaerobic digestion[21].However,the complex components of pulp and pa-per mill ef?uent are not signi?cantly reduced by biological pro-cesses and make the process very slow.Lignin is dif?cult to degrade by microorganisms.Therefore,the ef?uent from current treatment systems,which are mainly biological processes,still contains high levels of color,TOC and COD and signi?cant lignin concentrations.Thus,several chemical processes for treatment of paper mill ef?uents in tertiary processes have been studied exten-sively,including rapid?ltration through soil,ultra and nano ?ltration,ion-exchange,adsorption on activated carbon[21,22]. Electrocoagulation is a process known for its effectiveness in treat-ing charged ef?uents.In recent years,electrocoagulation(EC)has been successfully tested to treat various charged wastewaters.It can be used for many purposes such as removal of heavy metals [23],treatment of textile ef?uents[24,25]or aircraft industry ef?u-ent[26]and has been widely tested to treat pulp and paper mill ef?uents[4–6,11,27,28].

Electrocoagulation(EC)is an electrolytic process consisting in the dissolution of sacri?cial anodes made out of iron or aluminum upon application of a current between two electrodes for treat-ment of liquid wastewater containing inorganic or organic matter. As a matter of fact,Al3+or Fe2+/Fe3+ions generated by the dissolu-tion form neutral hydroxide complexes which act as coagulating agents for the suspended pollutants[24].The dissolution of the aluminium anode produces cationic species such as Al3+and AleOHTt

2

at low pH,which at pH near the neutrality are trans-formed into Al(OH)3and then polymerized to Al n(OH)3n[29]. According to the predominant zone diagram for aluminium hydroxide[30],the trivalent aluminium ion combines with OHàions to form aluminium hydroxides depending on pH,and the neu-tral and,insoluble form Al(OH)3predominates for pH close to7. With an iron anode,Fe(OH)n with n=2or3is formed.Two mech-anisms have been suggested for this production[31]:either Fe(OH)2is formed at the anode,while hydrogen is produced at the cathode from water,or Fe(OH)3is formed at the anode while hydrogen is produced at the cathode from H+ions.It is often con-sidered that the cationic charges produced by the dissolution neu-tralize the suspended impurities which are negatively charged for pH>3:the neutral entities formed are destabilized and can coa-lesce to larger and separable agglomerates.

In general,EC is directly applied to the paper mill ef?uent [28,32].However,in the present study,the ef?ciency of EC as a ter-tiary treatment was tested for the polishing of an industrial paper mill ef?uent.This ef?uent is subject to very strict discharge limits by local authorities(DREAL1):the limits have been set to470mg/L for COD and20l g/L for arsenic,but they can be lowered in case of low river water?ow rate.The performance of this process on mildly charged wastewaters has not been studied well.Thus,this work was aimed at experimentally investigating the ef?ciency of an EC step followed by sludge settling.

The EC ef?ciency was investigated at two values of current den-sity and with aluminum or iron electrodes in terms of removal of DOC(Dissolved Organic Carbon),COD,fulvic acids and arsenic (as an example of a non-organic micropollutant)and sludge production.

2.Materials and methods

2.1.Sampling of the paper mill wastewater

The wastewater used in this study was sampled at the outlet of the wastewater treatment plant(WWTP)of a pulp and paper mill located in Lorraine,France.The WWTP treatment includes a grid for solid removal,a primary settling treatment,and a secondary biological treatment by activated sludge.The wastewater was col-lected at the outlet of the clari?er located downstream of the bio-logical treatment and kept at4°C until use.Prior to testing in laboratory,the collected wastewater was thoroughly mixed in the storage tank for homogeneity.Each test required 2.5L of wastewater that was brought back to20°C.The typical character-istics of the wastewater are presented in Table1.

2.2.Experimental set-up

Treatment was carried out in a batch system with two alumi-num or iron electrodes,under liquid phase recycle.The experimen-tal set-up did not include any settler,and settling tests were conducted separately after the EC treatment.

The EC cell was composed of two identical polymethacrylate halves(20cm long,10cm wide and5cm thick).Metal plates with an area of15?7cm2acted as electrodes and were imbedded in the polymeric halves,as described previously[25,33].The effective area of each electrode used for electrolysis was105cm2.The an-ode-to-cathode gap was maintained at2cm,corresponding to an inner cell volume of0.21L.The electrodes were connected to a DC power supply(AFX2930SB)providing current density ranging from50to200A/m2.The current was kept constant for90min for each run.The solution to be treated(volume=2.5L)was placed into a magnetically stirred tank from which was continuously circulated in the?ow circuit by means of a peristaltic pump at 0.300L/min.

At the end of the experiment,the mixture was poured into a glass column(46cm high and7.8cm in diameter)for a settling test.The height of the liquid/sludge interface was recorded at reg-ular intervals,and the data were used for the determination of the settling parameters.The overall process(EC and settling)was done in triplicate for each experimental conditions set.

2.3.Analytical methods

Samples(40mL)were collected in the reservoir every10min. Conductivity and pH were measured with a multi-parameter instru-ment(Consort C931,Turnhout,Belgium).Turbidity(NTU)was mea-sured at890nm using a Hanna Instruments(Ann Arbor,Michigan) LP2000spectrophotometer.The suspended concentration(SS)

Table1

Characteristics of the paper mill ef?uent used in the experiments.

Parameter Paper mill wastewater

pH7.7

Turbidity(NTU)35

COD(mg O2/L)285

DOC(mg/L)75

Arsenic(l g/L) 3.8

Conductivity(ms/cm) 1.22

Temperature(°C)20

Color Brown

1DREAL=Direction régionale de l’Environnement,de l’Aménagement et du

Logement

S.Zodi et al./Separation and Puri?cation Technology81(2011)62–6863

was determined by drying10mL of the suspension for12h at105°C in a crucible.

For arsenic analysis,an aliquot of each sample was allowed to settle for at least two hours.The supernatant was digested in concentrated nitric acid using a START D(Milestone,Sorisole,Italy) microwave digestion system.Total arsenic concentration was then measured in triplicate with an inductively coupled plasma mass spectrometry(ICP-MS,Series X.7Thermo Scienti?c,Illkirch, France)instrument equipped with a collision/reaction cell(C/RC) and a CETAC autosampler.A gas mixture of helium(93%)and hydrogen(7%)was used for the C/RC.

A sample aliquot was?ltered(?lter paper with a1.5l m pore size).The colorimetric micro-method(HACH(Loveland,Colorado) method8000)with an excess of hexavalent chromium and subse-quent measurement of the optical density using a HACH2400 spectrophotometer(Loveland,Colorado)was used for the soluble COD determination.Dissolved organic carbon(DOC)was deter-mined by a total organic carbon analyzer TOC-V CSH(Shimadzu) suitable for carbon levels in the range of4l g/L–25,000mg/L.With this device the sample is oxidized catalytically at680°C and the CO2produced by this combustion is measured by an infra-red detector.For COD and DOC measurements,the calibration curves were obtained using potassium hydrogeno-phtalate(Fluka,analyt-ical grade).

The UV–visible spectra of the?ltered samples were measured with an Anthelie Light(Secomam,Domont,France)spectropho-tometer;light absorbance was measured between200and 600nm using1-cm-path quartz cells.Synchronous?uorescence spectra were measured with a FL-2500spectro?uorimeter(Hitachi Corp.,Tokyo,Japan)in plastic cuvettes with using the difference between emission and excitation wavelengths of50nm.

3.Results and discussion

3.1.DOC and COD removal

The ef?ciency of DOC and COD abatement was monitored every ten minutes for90min(Fig.1).The average standard deviation be-tween triplicates is5%for DOC and4%for COD.The current density was?xed at100or150A/m2.The amount and the nature of hydro-lysis products formed by anodic dissolution depended on the cur-rent density and time.In experiments with Al electrodes,the Al3+ species generated formed monomeric and polymeric hydroxo com-plexes,depending on the pH range[34].Ionic forms are soluble; neutral hydroxides are solids.With iron electrodes,the generated Fe2+ions oxidize to Fe3+species in the form of monomeric ions and ferric hydroxo complexes with hydroxide ions and polymeric species,depending also on the pH[35].As seen in Fig.1a,after 90min of EC treatment,the DOC abatement obtained with Al elec-trodes was higher than with Fe electrodes.The maximum DOC re-moval at100and150A/m2was38%and46%,respectively,with Al electrodes,and24%and31%,respectively,with Fe electrodes.At the end of the runs,the COD abatement was47%and68%(for Al electrodes)and32%and41%(for Fe electrodes)at100and 150A/m2,respectively.Katal and Pahlavandazeh[28]obtained better results with Fe electrodes than with Al electrodes but they worked with raw paper mill ef?uents which had much higher COD and suspended solids contents than the ef?uent used in the present study.Both abatements increased with time,although they seemed to stabilize during the last30min of the experiment.Dis-solved organic substances are supposed to be the main component of DOC and COD.Generally,strong oxidizing agents such as hydro-gen peroxide are used to oxidize such substances.The removal of COD and DOC by EC could be attributed to the removal of sus-pended solids.Due to the slightly alkaline pH of the wastewater (7.7),Fe3+species formed after anode dissolution are in the insol-uble form Fe(OH)3.Aluminum anodes behave differently because both ionic and neutral forms of aluminum hydroxide can exist [34].The effect of pH was not investigated.In the pulp and paper mill the ef?uent pH varies between7and8,in agreement with the requirements for discharge to the river.Even if it is not optimal for EC,it was decided to keep it at its natural value,in order to avoid having to bring it back to a value in agreement with dis-charge limits.The non adjustment of pH was also advocated by Ka-tal and Pahlavanzadeh[28].The current density in?uences the performance of the EC process because it determines the dose of coagulant produced at the electrode.This is directly related to the higher amount of metals dissolved by the larger electrical charge and therefore to the higher coagulant dose[36].

3.2.Spectroscopic measurements

The organic matter derived from lignin and present in the liquid exhibited?uorescence emission properties with a peak at k ex=362nm and k em=412nm.UV–visible absorbance and syn-chronous?uorescence spectroscopy were two methods that were used to provide more detailed information about pollution removal during the EC treatment.

3.2.1.UV–visible spectroscopy

The EC treatment was particularly ef?cient at turbidity removal. In fact,turbidity was completely removed after60min with Al electrodes at150A/m2.Particles that contributed to the turbidity coagulated and settled more rapidly than the dissolved pollution (Fig.2a).Increasing the current density was found to improve the treatment with Al electrodes more than the treatment with

64S.Zodi et al./Separation and Puri?cation Technology81(2011)62–68

Fe electrodes.The treatment with Fe and Al electrodes had differ-ent kinetics.In fact,with Fe electrodes,the turbidity decreased rap-idly in the?rst20min,but at the end of the treatment,the removal remained incomplete.In contrast,with Al electrodes,there was no turbidity abatement during the?rst10min,but in the second part of the treatment,Al electrodes had higher removal ef?ciency than the Fe electrodes.The absorbance at254nm(A254)(a surrogate measurement for DOC and soluble COD)[37]decreased with time until90min for the Al electrodes but stabilized after50min for the Fe electrodes(Fig.2b).The residual absorbance was higher for Fe electrodes than for Al electrodes.SUVA254(=A254(mà1)/DOC(mg/ L))(Fig.2c)and the E2/E3index(the ratio of the absorbance at 250nm to the absorbance at365nm)(Fig.2d)decreased with time for the four EC experimental conditions.This re?ects differences in the removal of substances containing aromatic structures[38].The decrease of SUVA254indicates that UV-sensitive structures,which are hydrophobic and easier to remove by coagulation,were better eliminated than other substances contained in organic matter[39]. The decrease of E2/E3can be related to an increase of the average molecular weight of the residual organic matter[40].

3.2.2.Synchronous?uorescence spectroscopy

Baker[41]reported that pulp and paper mill wastewater contain lignin derivate compounds that exhibit a fulvic-like?uorescence peak.Those compounds are only partially removed by the activated sludge treatment.The synchronous?uorescence spectra of the samples were recorded for D k=50nm where D k=k emàk ex (Fig.3).Synchronous?uorescence spectra are usually more struc-tured(i.e.they exhibit well de?ned peaks)than emission or excita-tion spectra[42,43]and were therefore preferred in the present study.In the present case a large peak of fulvic-like?uorescence,re-lated to the lignin derivate compounds,was measured at an excita-tion wavelength of362nm.The results showed that,after90min, EC removed50%of this?uorescence signal when Al electrodes were used and75%of this?uorescence with the use of Fe electrodes (Fig.4).This result is a key factor to support the use of EC as a ter-tiary treatment,as a way to remove lignin derivate compounds from the reclaimed wastewater.A temporary increase of the?uo-rescence can be observed in the experiments with both types of electrodes at150A/m2,the phenomenon being more pronounced with the Al electrodes.One hypothesis is that in the early moments of the experiments at150A/m2,the coagulation removes from the liquid phase some compounds which are able to quench the?uo-rescence[44].This could relax?uorescence quenching.Further experiments are necessary to verify this assumption.

3.3.Arsenic removal

The decrease of arsenic concentration with respect to time is shown in Fig.5.More than91.5%of arsenic was removed with Al electrodes at100A/m2.The removal ef?ciency reached86%and 88%at100and150A/m2,respectively,when Fe electrodes were used.Thus,either Fe or Al plates used as sacri?cial electrodes in the EC process are ef?cient for arsenic removal.

The rate of arsenic removal was high at the beginning of the process but stabilized after the?rst hour.Longer treatment time did not improve the residual arsenic concentration as shown by the constant arsenic concentration.At a higher pH,the formation rate of metal–arsenate/arsenite complexes may be lower due to solubility effects[45].The low rate of arsenic removal after 60min can be explained by the negative charge of the predominate As(V)in the pH range of4–10,whereas the As(III)species generally has no net charge[45].Based on this,the As(V)removal ef?ciency is expected to be higher than the As(III)removal,As(III)remaining in the ef?uent.

We observed that the arsenic removal with Fe electrodes was faster than the arsenic removal with Al electrodes.The adsorption of As(V)on Fe3+species is known to be more ef?cient than on Al3+ species and As(V)is adsorbed or precipitated with the oxide.How-ever,the air bubbling not only oxidizes Fe2+to Fe3+but also

S.Zodi et al./Separation and Puri?cation Technology81(2011)62–6865

promotes the coagulation/?occulation process due to turbulence in the electrocoagulation unit of the cell[46].Moreover,higher cur-rent density means a higher Fe3+and OHàdosage,and an improved removal should therefore be expected.Increasing the current den-sity to150A/m2improves As removal with Al electrodes.3.4.Sludge settleability

Sludge settleability can be expressed mainly by the sludge vol-ume index(SVI),which is often recommended for characterization of produced sludge[47].SVI(L/g)is de?ned by:

66S.Zodi et al./Separation and Puri?cation Technology81(2011)62–68

SVI?

H30

H0áC0

e1T

where H0is the initial height of the EC treated ef?uent in the set-tling column,H30is the sludge height after a30min settling,and C0(in g/L)is the total sludge concentration at t=0after electroco-agulation treatment.

With Al electrodes,SVI varied with the applied current density. It was0.207L/g at100A/m2and reached0.310L/g at150A/m2. The high SVI values are due to the fact that the sludge formed by Al electrodes was light and?uffy and the fact that the foam formed during the EC treatment by an Al electrode prevents a tight layer after settling.Although it increased the sludge concentration,the increase in current density up to150A/m2allowed larger?oc sizes and reduced their density and hence hindered their settleability. The sludge layer formed after settling in this case was far less com-pact,which explained the50%increase from100to150A/m2.With Fe,the current density had little effect on SVI,as shown by the much lower SVI values,varying from0.091L/g at100A/m2down to0.081L/g at150A/m2.The sludge formed by Fe electrodes was heavy enough to produce a compact layer.When the current den-sity was increased,the sludge?oc size increased,and after settling the sludge layer became thinner and more compact.

4.Conclusion

EC is a process known for its ef?ciency in treating highly pol-luted ef?uents.In this study,contrary to industrial practice,we tested the effectiveness of the process as a tertiary treatment for the industrial ef?uent of a paper mill.Not only was EC able to re-duce the global pollution,in terms of COD and DOC,but spectro-scopic techniques(UV–visible and?uorometry)showed that the aromaticity of the organic pollution decreased and that the lig-nin-related pollution was very signi?cantly reduced.Non-organic micropollutants were also removed.The experiments showed fair arsenic abatement,from3.8l g/L after activated sludge treatment to less than0.4l g/L and0.5l g/L with Al and Fe electrodes,respec-tively.Although the global ef?ciency obtained with Al electrodes was slightly better than that obtained with Fe electrodes(except for the lignin-related pollution),the EC sludge obtained with Fe electrodes was easier to handle than the one produced by Al elec-trodes.This favors the use of Fe electrodes for future work,in par-ticular for the scale-up of a continuous process and the optimization of the design parameters(such as the gap between the electrodes).

References

[1]European Commission,Integrated pollution prevention and control(IPPC)

reference.Document on best available techniques in the pulp and paper industry.Brussels,Belgium(2001).

[2]K.J.Kramer,E.Masanet,T.Xu,E.Worrell,Energy ef?ciency improvement and

cost saving opportunities for the pulp and paper industry,An ENERGY STAR guide for energy and plant managers,Ernest Orlando Lawrence Berkeley National Laboratory,University of California,Berkeley,California,2009.

[3]M.Boroski,A.C.Rodrigues,J.C.Garcia,A.P.Gerola,J.Nozaki1,N.Hioka,The

effect of operational parameters on electrocoagulation–?otation process followed by photocatalysis applied to the decontamination of water ef?uents from cellulose and paper factories,J.Hazard.Mater.160(2008)135–141. [4]S.Khansorthong,M.Hunsom,Remediation of wastewater from pulp and paper

mill industry by the electrochemical technique,Chem.Eng.J.151(2009)228–234.

[5]E.S.Z.El-Ashtoukhy,N.K.Amin,O.Abdelwahab,Treatment of paper mill

ef?uents in a batch-stirred electrochemical tank reactor,Chem.Eng.J.146 (2009)205–210.

[6]K.Eskelinen,H.T.S?rkk?, A.M.Kurniawan, E.T.Sillanp??,Removal of

recalcitrant contaminants from bleaching ef?uents in pulp and paper mills using ultrasonic irradiation and Fenton-like oxidation,electrochemical treatment,and/or chemical precipitation:a comparative study,Desalination 255(2010)179–187.

[7]National Registry of Industrial Pollutants.

industrielles.ecologie.gouv.fr/IREP/index.php>.(Accessed on10August2010).

[8]M.L.Hewitt,T.G.Kovacs,M.G.Dube, D.L.MacLatchy,P.H.Martel,M.E.

McMaster,M.G.Paice,J.P.Parrott,M.R.Van Den Heuvel,G.J.Van Der Kraak, Altered reproduction in?sh exposed to pulp and paper mill ef?uents:roles of individual compounds and mill operating conditions,Environ.Toxic.Chem.27 (2008)682–697.

[9]M.Sillanp??,V.Vicˇkacˇkaitè,L.Niinist?,M.L.Sihvonen,Distribution and

transportation of ethylenediaminetetraacetic acid and diethylenetriamine-pentaacetic acid in lake water and sediment,Chemosphere35(1997) 2797–2805.

[10]Z.Aksu,F.G?nen,Biosorption of phenol by immobilized activated sludge in a

continuous packed bed:prediction of breakthrough curves,Proc.Biochem.39 (2004)599–613.

[11]M.Ugurlu,A.Gürses,?.Dogarc,M.Yal?in,The removal of lignin and phenol

from paper mill ef?uents by electrocoagulation,J.Environ.Manag.87(2008) 420–428.

[12]J.F.Martinez-Villafane, C.Montero-Ocampo, A.M.Garcia-Lara,Energy and

electrode consumption analysis of electrocoagulation for the removal of arsenic from underground water,J.Hazard.Mater.172(2009)1617–1622. [13]World Health Organization,Guidelines for drinking-water quality1(2008)

306–308.

[14]U.K.Chowdhury,M.M.Rahman, B.K.Mondal,K.Paul, D.Lodh,G.K.Basu,

Groundwater arsenic contamination and human suffering in West Bengal, India and Bangladesh,Environ.Sci.8(2001)393–415.

[15]D.Chakraborti, B.Das,M.M.Rahman,U.K.Chowdhury, B.Biswas, A.B.

Goswami,B.Nayak,A.Pal,M.K.Sengupta,S.Ahamed,A.Hossain,G.Basu,T.

Roychowdhury,D.Das,Status of groundwater arsenic contamination in the state of West Bengal,India:a20-year study report,Mol.Nutr.Food Res.53 (2009)542–551.

[16]M.Walker, D.Fosbury,Arsenic,As(III),and tungsten in Nevada County’s

private water supplies,J.Wat.Health7(2009)293–301.

[17]P.F.Hudak,Distribution of arsenic concentrations in groundwater of the

Seymour Aquifer,Texas,USA,Int.J.Environ.Health Res.18(2008)79–82. [18]S.C.Peters,Arsenic in groundwaters in the Northern Appalachian Mountain

belt:a review of patterns and processes,J.Contam.Hydrol.99(2008)8–21.

[19]A.Gaid,I.Raguenes,P.Ravarini,Arsenic removal at Baudricourt(Vosges–

France)drinkable water plant,Eau.Industrie.Nuisances205(1997)54–58.

[20]C.Michon,M.N.Pons,P.Bauda,M.Bortolotti,O.Potier,J.L.Duren,Impact of

anthropogenic source of arsenic on the Moselle River,Wat.Sci.Technol.63 (2011)1349–1356.

[21]G.Thomson,J.Swain,M.Kay,C.F.Forster,The treatment of pulp and paper mill

ef?uent:a review,Biores.Technol.77(2001)275–286.

[22]S.Ciputra, A.Antony,R.Phillips, D.Richardson,G.Leslie,Comparison of

treatment options for removal of recalcitrant dissolved organic matter from paper mill ef?uent,Chemosphere81(2010)86–91.

[23]B.Merzouk,B.Gourich,A.Sekki,K.Madani,M.Chibane,Removal turbidity and

separation of heavy metals using electrocoagulation–electro?otation technique.A case study,J.Hazard.Mater.164(2009)215–222.

[24]S.Zodi,O.Potier,https://www.wendangku.net/doc/804504645.html,picque,J.P.Leclerc,Treatment of the textile wastewaters

by electrocoagulation:effect of operating parameters on the sludge settling characteristics,Sep.Purif.Technol.69(2009)29–36.

[25]S.Zodi,O.Potier, https://www.wendangku.net/doc/804504645.html,picque,J.P.Leclerc,Treatment of the industrial

wastewaters by electrocoagulation:optimization of coupled electrochemical and sedimentation processes,Desalination261(2010)186–190.

[26]Y.Meas,J.A.Ramirez,M.A.Villalon,T.W.Chapman,Industrial wastewaters

treated by electrocoagulation,Electrochim.Acta55(2010)8165–8171. [27]R.Sridhar,V.Sivakumar,V.Prince Immanuel,J.Prakash Maran,Treatment of

pulp and paper industry belaching ef?uent by electrocoagulation process,J.

Hazard.Mater.(2011).doi:10.1016/j.jhazmat.2010.12.028.

[28]R.Katal,H.Pahlavanzadeh,In?uence of different combinations of aluminium

and iron electrode on electrocoagulation ef?ciency.Application to the treatment of paper mill wastewater,Desalination265(2011)199–205. [29]M.Y.A.Mollah,R.Schennach,J.P.Panga,D.L.Cocke,Electrocoagulation(EC):

science and applications,J.Hazard.Mater.384(2001)29–41.

[30]P.K.Holt,G.W.Barton,M.Wark, C.A.Mitchel,A quantitative comparison

between chemical dosing and electrocoagulation,Colloids Surf.A211(2002) 233–248.

[31]https://www.wendangku.net/doc/804504645.html,rue,E.Vorobiev,Floc size estimation in iron induced electrociagulation

and coagulation using sedimentation data,Int.J.Min.Proc.71(2003)1–15.

[32]M.Tejocote-Pérez,P.Balderas-Hernández, C.E.Barrera-Diáz,G.Roa-

Morales,R.Natividad-Rangel,Treatment of industrial ef?uents by a continuous system:electrocoagulation-activated sludge,Biores.Technol.

101(2010)7761–7766.

[33]I.Zongo,A.Ma?ga,J.Wéthé,G.Valentin,G.Paternotte,J.P.Leclerc,https://www.wendangku.net/doc/804504645.html,picque,

Electrocoagulation for the treatment of textile wastewaters with Al or Fe electrodes:compared variations of COD levels,turbidity and absorbance,J.

Hazard.Mater.169(2009)70–76.

[34]I.L.Hernandez,C.B.Diaz,G.R.Morales,B.Bilyeu,F.U.Nunez,In?uence of the

anodic material on electrocoagulation performance,Chem.Eng.J.148(2009) 97–105.

[35]I.Zongo,J.P.Leclerc,H.A.Ma?ga,J.Wéthé,https://www.wendangku.net/doc/804504645.html,picque,Removal of hexavalent

chromium from industrial wastewater by electrocoagulation:a comprehensive comparison of aluminium and iron electrodes,Sep.Purif.

Technol.66(2009)159–166.

[36]U.T.Un, A.S.Koparal,U.B.Ogutveren,Electrocoagulation of vegetable oil

re?nery wastewater using aluminum electrodes,J.Environ.Manag.90(2009) 428–433.

S.Zodi et al./Separation and Puri?cation Technology81(2011)62–6867

[37]M.Mrkva,Evaluation of correlation between absorbance at254nm and COD of

river waters,Water Res.17(1983)231–235.

[38]N.J.O’Driscoll,S.D.Siciliano,D.Peak,R.Carignan,D.R.S.Lean,The in?uence of

forestry activity on the structure of dissolved organic matter in lakes: implications for mercury photoreactions,Sci.Total Environ.366(2006)880–893.

[39]M.Drikas,M.Dixon,J.Morran,Long term case study of MIEX pre-treatment in

drinking water:understanding NOM removal,Water Res.45(2011)1539–1543.

[40]J.Peuravuoni,K.Pihlaja,Molecular size distribution and spectroscopic

properties on aquatic humic substances,Anal.Chim.Acta337(1997)133–149.

[41]A.Baker,Fluorescence excitation–emission matrix characterization of river

waters impacted by a tissue mill ef?uent,Environ.Sci.Technol.36(2002) 1377–1382.

[42]J.Peuravuori,R.Koivikko,K.Pihlaja,Characterization,differentiation and

classi?cation of aquatic humic matter separated with different sorbents: synchronous scanning?uorescence spectroscopy,Wat.Res.36(2002)4552–4562.[43]M.M.D.Sierra,M.Giovanela, E.Parlanti, E.J.Soriano-Sierra,Fluorescence

?ngerprint of fulvic and humic acids from varied origins as viewed by single-scan and excitation/emission matrix techniques,Chemosphere58(2002)715–733.

[44]S.Maji,K.Sundararajan,K.S.Viswanathan,Correction for quenching in

?uorimetric determinations using steady state?uorescence,Spectrochim.

Acta Part A:Mol.Biomol.Spectros.56(2000)1251–1256.

[45]J.A.G.Gomesa,P.Daida,M.Kesmez,M.Weir,H.Moreno,J.R.Parga,G.Irwin,

H.D.McWhinney,T.Grady, E.Peterson, D.L.Cocke,Arsenic removal by

electrocoagulation using combined Al–Fe electrode system and characterization of products,J.Hazard.Mater.139(2007)220–231.

[46]H.K.Hansen,P.Nunez,R.Grandon,Electrocoagulation as a remediation tool for

wastewaters containing arsenic,Min.Eng.19(2006)521–524.

[47]M.Da Motta,M.N.Pons,N.Roche,Automated monitoring of activated

sludge in a pilot plant using image analysis,Wat.Sci.Technol.43(7) (2001)91–96.

68S.Zodi et al./Separation and Puri?cation Technology81(2011)62–68

(完整word版)工程管理专业英语徐勇戈课-第二版-后答案

专业英语 Unit1 第一题1.设计/施工过程Design and construction process 2.房地产开发商Real estate developer 3.投机性住宅市场Speculative housing market 4.项目管理Project management 5.项目全寿命期Project life cycle 6.项目范围Scope of a project/project scope 7.专业化服务Professional services 8.重大基础项目建设Construction of major infrastructure projects 9.住宅类房屋建设Residential housing construction 10.办公和商业用房建设office and commercial building construction 11.专业化工业项目建设Specialized industrial projects construction 12.专业咨询师Professional consultants 13.总承包商Original contractor 14.价值工程value engineering 15.竞争性招标Competitive bidding 16.建筑和工程设计公司Architectural and engineering design company 17.运营与维护管理operation and maintenance 18.设计/施工公司design and construction company 19.分包商subcontractor 20.设施管理facility management 第一章 1、从项目管理的角度看，“业主”和“发起方”是同义的，因为两者的基本权力是制定所有重大决策。 2、项目范围界定后，详细的工程设计将提供建设蓝图，最终费用估计将作为控制成本的基准。 3、此外，业主可用内部能力处理整个过程中每一个阶段的工作，或者它可能会在各个阶段寻求专业意见及服务。 4、业主可以根据项目的规模和性质选择把整个过程或多或少的分解到各个阶段上，从而获得在实施中最有效的结果。 5、所有的组织方法各有利弊，这取决于在施工管理中的业主的知识以及项目的类型，规模和位置。 6、各类建筑的规划、采购的专业服务、建筑合同的制定、以及建筑设施融资的方法都可以完全不同。 7、. 专门的工业建筑，通常涉及技术复杂程度高，如炼油厂，钢铁厂，化学处理厂和燃煤或核电厂等的大型项目，如图1-4所示。 8、传统上，在初步设计开发阶段，业主作为技术顾问从事于建筑和工程（A / E）的公司或集团。 9、通过集成到一个单一的组织设计和施工管理，设计者和建筑者之间的许多冲突是可以避免的。 10、近年来，建设项目从成立到完成，新的施工管理人员（CM）的提供专业服务。 11、因此，业主必须明白自己的责任，也希望把过程中的风险分配给自己和其他参与者。 12、除非业主或专业的施工经理执行此功能，一个良好的总承包商会与他的团队合作，专业的承包商或分包商作过的项目数量在过去可以最有效的鼓励人的忠诚与合作。 13、例如，在纽约，专业承包商，如机械和电气承包商，不受建设项目总承包商的监督，公共项目初期必须签订独立合约。 14、主要原料供应商，包括钢结构制造和架设，金属板材，预拌混凝土输送，钢筋详图，屋面，玻璃等专业承包商。 第二章

环境工程专业英语汇总

专业英语 环境：environment 环境工程：environmental engineering 环境保护：environmental protection 环境意识：environmental consciousness/awareness 环境问题：environmental issue/problem 环境效应：environmental effect 环境污染：environmental pollution 环境要素：environmental elements 环境因子：environmental factors 环境化学：environmental chemistry 环境生态学：environmental ecology 环境质量：environmental quality 环境自净作用：environmental self-purification/self-cleansing 水环境：watershed 水体：water body 流域：watershed 水质：water quality 水资源：water resources 供水：water supply 废水：waste water 水处理：water treatment 物理性水质指标：physical indicate of water quality 水污染物：water pollutant 生物性水质指标：biological water-quality index 水质标准：water quality standard 化学性水质指标：chemical water-quality index DS：dissolved solids BOD：biochemical oxygen demand TDS：total dissolved solids COD：chemical oxygen demand TSS：total suspended solids DO：dissolved oxygen TOC：total organic carbon PH值： TN：总氮total nitrogen TP：总磷phosphorus Zn：zinc Cu：Copper As：arsenic Cd：Cadmium Cr：chromium Ni：Nickel Hg：mercury Pb：plumbum 物理处理：physical treatment 过滤：screening 生物处理：biological treatment 沉淀：sedimentation 化学处理：chemical treatment 气浮：flotation 物理化学处理：physical-chemical treatment 蒸发：evaporation 稀释：dilution 扩散：dispersion 吹脱：stripping 好氧处理：aerobic treatment 生物膜法：bio-membrane process 厌氧处理：anaerobic treatment 生物滤池：trickling filters 活性污泥法：activated sludge process 生物接触氧化：biological contact SBR：苯乙烯-丁二烯Styrene Butadiene Rubber UASB（流式厌氧污泥床）：Upflow anaerobic sludge blanket 活性污泥：activated sludge 改进型：modification 一级处理：primary treatment 二级处理：secondary treatment 三级处理：tertiary treatment 高级氧化处理：advanced treatment 生活污水：domestic wastewater 生产废水：industrial wastewater 城市生活污水：municipal wastewater 电镀废水：metalplating plants 印染废水：pulp and paper industries wastewater 浊度：turbidity 硬度：hardness 水质净化：water quality purifies 混凝沉淀：coagulate flocculating agent 活性炭吸附：activated carbon adsorption

安全工程专业英语部分翻译

Unit 1 safety management system Accident causation models 事故致因理论 Safety management 安全管理Physical conditions 物质条件 Machine guarding 机械保护装置 House-keeping 工作场所管理 Top management 高层管理人员 Human errors 人因失误Accident-proneness models 事故倾向模型 Munitions factory 军工厂Causal factors 起因Risking taking 冒险行为Corporate culture 企业文化Loss prevention 损失预防Process industry 制造工业Hazard control 危险控制Intensive study 广泛研究Organizational performance 企业绩效 Mutual trust 相互信任Safety officer 安全官员 Safety committee 安全委员会Shop-floor 生产区Unionized company 集团公司Seniority 资历、工龄Local culture 当地文化 Absenteeism rate 缺勤率Power relations 权力关系Status review 状态审查 Lower-level management 低层管理者 Business performance 组织绩

效 Most senior executive 高级主管 Supervisory level 监督层Safety principle 安全规则Wall-board 公告栏Implement plan 执行计划Hazard identification 危险辨识 Safety performance 安全性能 One comprehensive definition for an organizational culture has been presented by Schein who has said the organizational culture is “a pattern of basic assumptions – invented, discovered, or developed by a given group as it learns to cope with its problems of external adaptation and internal integration –that has worked well enough to be considered valid and, therefore, to be taught to new members as the correct way to perceive, think, and feel in relation to those problems” 译文：Schein给出了组织文化的广泛定义，他认为组织文化是由若干基本假设组成的一种模式，这些假设是由某个特定团体在处理外部适应问题与内部整合问题的过程中发明、发现或完善的。由于以这种模式工作的有效性得到了认可，因此将它作为一种正确的方法传授给新成员，让他们以此来认识、思考和解决问题[指适应外部与整合内部的过程中的问题]。 The safety culture of an organization is the product of individual and group values, attitudes, perceptions, competencies, and patterns of behavior that determine the commitment to, and the style and proficiency of , an organization’s health and safety management. 译文：组织的安全文化由以下几项内容组成：个人和群体的价值观、态度、观念、能力和行为方式。这种行为方式决定了个人或团体对组织健康安全管理的责任，以及组织健康安全管理的形式和熟练程度。 Unit 2 System Safety Engineering System safety engineering 系统安全工程By-product 附带产生的结果

环境科学与工程专业英语翻译

第二单元环境工程 这本书主要关于什么？ 这本书的目标是使工程和科学的学生了解学科间的研究环境问题：它们的起因，为什么它们被关注，我们怎么控制它们。这本书包括： ●描述环境和环境系统意味着什么 ●关于环境破坏基础原因的信息 ●理解环境问题本质和能够定量计算它们所必要的基本科学知识 ●目前运用在水,空气,污染问题的环境控制技术的状况 ●我们目前在很多关于理解和控制人类活动、自然之间复杂相互作用的科学知识上存在着相当大的空白 ●很多环境问题能运用目前的技术消除或减少，但因为社会缺少意愿这么做或在很多例子中因为缺乏资源去这样做，这些环境问题没有被处理 一些重要的定义： 在这本书中，它们第一次被使用，定义被以大写或印刷成黑体字的形式展示 环境是围绕在我们周围的物质生命的栖息地，在这儿我们能看到,听到,触摸,闻到,和品尝到 系统依据韦氏字典,被定义为“一组或一系列能形成一个整体或者有机整体的相互关联的事物”，例如，太阳系统，灌溉系统，供应系统，世界和宇宙。 污染被定义为“在大气，水或土地中的物质的，化学的或生物的特性的不合意的改变，这一改变有害地影响人类或其它生物的健康，生存，或活动”。 当改进环境质量的目标被用来改进人类福利，“环境”一词扩展成包括所有的社会，经济和文化方面的内容。这一扩展在许多真实情况下是不可行的以及在一本被设计为一学期课程的教科书中也是不实际的。我们对环境问题的考察因此限于我们对“环境”的定义。 系统的相互作用 许多不同的环境问题都与水，空气或土地系统有关联。许多这些问题都只适用于这些系统中的一个，这为这些种类中的细目分类提供了充分的理由。这样的分类也更有用于及易于理解一个系统内的相关问题。而且，这样做是明智的，这是因为由于管理上的和行政上的原因，这些有关空气污染，水供应，废水处理和固体废物处理的子域通常由政府机构分别处理。 很遗憾的是，很多重要的环境问题不仅仅限制于空气，水或土地系统，还包括系统间的相互作用。现在举个例子，酸雨问题起源于从发电站烟囱，冶炼厂和汽车尾气中向大气排放的含硫二氧化物和氮氧化物。接着这些气体由气流运输到广阔的区域，降雨“将它们洗去”，产生了有害于水生生命，森林和农作物的酸雨。两个有关于系统间相互作用引起的环境问题有：空气中的二氧化碳的增加的全球问题，及通常具有地域性质的酸雨问题。 环境问题 许多对我们生活标准的主要改进能被归因于科学和技术的运用。这里举一些例子，你能想出其它例子吗？ ●生产更多及更好质量的食物 ●创造能避免极端环境的保护所和生存空间 ●快速和可靠的运输方法的建立 ●各种交流系统的发明 ●代替人类和动物体力的机器的发明 ●安全水的供应和废物处理 ●对很多传染疾病的消除

安全工程专业英语Unit1-9翻译

安全工程专业英语 Unit1 1. Because of the very rapid changes in these jobs and professions, it is hard for students to learn about future job opportunities. It is even more difficult to know about the type of preparation that is needed for a particular profession-or the qualities and traits that might help individuals succeed in it. 由于这些工作和职业的飞速变更，其变化之快使得学生们很难了解未来有什么样的工作机会，更不知道为未来的具体职业生涯做出怎样的准备，也就是说学生们很难知道掌握何种知识、具备何种能力才能成功适应未来的社会。 2. The purpose of this article is to provide in depth information about the safety profession that should help students considering a career in this challenging and rewarding field. 这篇文章将提供较为深入的安全专业方面的具体信息，它应该能够为安全专业的学生们在这个充满挑战也蕴含着发展机遇的职业中获得良好的发展而提供帮助。 3. While these efforts became more sophisticated and widespread during the twentieth century, real progress on a wide front did not occur in the U.S. until after Word War Ⅱ. 尽管这些专业手段在20世纪已经发展的较为成熟，也具有一定的广泛适应性，但在美国，这些都是第二次世界大战以后才取得的突破性进展。 4. This legislation was important because it stressed the control of workplace hazards. This, in turn, defined a clear area of practice for the previously loosely organized safety profession. Other legislation passed during the next twenty years has increased the scope of safety practice into areas of environmental protection, product safety, hazardous materials management and designing safety into vehicles, highways, process plants and buildings. 这部法律很重要，因为它强调工作场所的危险控制，同时这部法律也为以前不成体系的安全业务划定了工作范围。此后20年中通过的一

生物工程专业英语翻译(第二章)

Lesson Two Photosynthesis 内容： Photosynthesis occurs only in the chlorophyllchlorophyll叶绿素-containing cells of green plants, algae藻, and certain protists 原生生物and bacteria. Overall, it is a process that converts light energy into chemical energy that is stored in the molecular bonds. From the point of view of chemistry and energetics, it is the opposite of cellular respiration. Whereas 然而 cellular细胞的 respiration 呼吸is highly exergonic吸收能量的and releases energy, photosynthesis光合作用requires energy and is highly endergonic. 光合作用只发生在含有叶绿素的绿色植物细胞，海藻，某些原生动物和细菌之中。总体来说，这是一个将光能转化成化学能，并将能量贮存在分子键中，从化学和动能学角度来看，它是细胞呼吸作用的对立面。细胞呼吸作用是高度放能的，光合作用是需要能量并高吸能的过程。Photosynthesis starts with CO2 and H2O as raw materials and proceeds through two sets of partial reactions. In the first set, called the light-dependent reactions, water molecules are split裂开 (oxidized), 02 is released, and ATP and NADPH are formed. These reactions must take place in the presence of 在面前 light energy. In the second set, called light-independent reactions, CO2 is reduced (via the addition of H atoms) to carbohydrate. These chemical events rely on the electron carrier NADPH and ATP generated by the first set of reactions. 光合作用以二氧化碳和水为原材料并经历两步化学反应。第一步，称光反应，水分子分解，氧分子释放，ATP和NADPH形成。此反应需要光能的存在。第二步，称暗反应，二氧化碳被还原成碳水化合物，这步反应依赖电子载体NADPH以及第一步反应产生的ATP。 Both sets of reactions take place in chloroplasts. Most of the enzymes and pigments 色素for the lightdependent reactions are embedded 深入的内含的in the thylakoid 类囊体 membrane膜隔膜 of chloroplasts 叶绿体. The dark reactions take place in the stroma.基质 两步反应都发生在叶绿体中。光反应需要的大部分酶和色素包埋在叶绿体的类囊体膜上。暗反应发生在基质中。 How Light Energy Reaches Photosynthetic Cells（光合细胞如何吸收光能的） The energy in light photons in the visible part of the spectrum can be captured by biological molecules to do constructive work. The pigment chlorophyll in plant cells absorbs photons within a particular absorption spectrums statement of the amount of light absorbed by chlorophyll at different wavelengths. When light is absorbed it alters the arrangement of electrons in the absorbing molecule. The added energy of the photon boosts the energy condition of the molecule from a stable state to a less-stable excited state. During the light-dependent reactions of photosynthesis, as the absorbing molecule returns to the ground state, the "excess" excitation energy is transmitted to other molecules and stored as chemical energy. 生物分子能捕获可见光谱中的光能。植物细胞中叶绿素在不同光波下吸收部分吸收光谱。在吸收分子中，光的作用使分子中的电子发生重排。光子的能量激活了分子的能量状态，使其

工程管理专业英语翻译(第二版)徐勇戈

U2-S1什么是项目管理？ 建筑项目管理不仅需要对设计和实施过程有所理解，而且需要现代管理知识。建设项目有一组明确的目标和约束，比如竣工日期。尽管相关的技术、组织机构或流程会有所不同，但建设项目同其他一些如航天、医药和能源等准等领域的项目在管理上仍然有共同之处。 一般来说，项目管理和以项目任务为导向的企业宏观管理不同，待项目任务的完成后，项目组织通常也会随之终止。（美国）项目管理学会对项目管理学科有如下定义：项目管理是一门指导和协调人力物力资源的艺术，在项目整个生命周期，应用现代管理技术完成预定的规模、成本、时间、质量和参与满意度目标。 与此形成对照，一般的工商企业管理更广泛地着眼于业务的更加连贯性和连续性。然而，由于这两者之间有足够的相似和差异，使得现代管理技术开发宏观管理可以用于项目管理。 项目管理框架的基本要素可以用图2-1表示。其中，应用宏观管理知识和熟悉项目相关知识领域是不可或缺的。辅助性学科如计算机科学和决策科学也会发挥重要作用。实际上，现代管理实践与各专业知识领域已经吸收应用了各种不同的技术和工具，而这些技术和工具曾一度仅仅被视作属于辅助学科领域。例如，计算机信息系统和决策支持系统是目前常见的宏观管理工具。同样，许多像线性规划和网络分析这样的运算研究工具，现在广泛应用在许多知识和应用领域。因此，图2- 1反映了项目管理框架演变的唯一来源。 具体来说，建设项目管理包含一组目标，该目标可能通过实施一系列服从资源约束的运作来实现。在规模、成本、时间和质量的既定目标与人力、物力和财力资源限制之间存在着潜在冲突。这些冲突应该在项目开始时通过必要的权衡和建立新备选方案来解决。另外，施工项目管理的功能通常包括以下: 1. 项目目标和计划说明书中包括规模、预算安排、进度安排、设置性能需求和项目参与者的界定。 2. 根据规定的进度和规划，通过对劳动力、材料和设备的采购使资源的有效利用最大化。 3. 在项目全过程中，通过对计划、设计、估算、合同和施工的适当协调控制来实施项目各项运作。 4. 设立有效的沟通机制来解决不同参与方之间的冲突。 项目管理学会聚焦九个不同独特领域，这些领域需要项目经理所具有的知识和关注度： 1. 项目宏观管理，确保项目要素有效协调。 2. 项目范围管理，确保所需的所有工作（并且只有所需的工作）。 3. 项目时间管理，提供有效的项目进度。 4. 项目成本管理，确定所需资源和维持预算控制。 5. 项目质量管理，确保满足功能需求。 6 . 项目人力资源管理，有效地开发和聘用项目人员。 7 . 项目沟通管理，确保有效的内部和外部通信。 8. 项目风险管理，分析和规避潜在风险。 9. 项目采购管理，从外部获得必要资源。

(完整版)环境工程专业英语考试重点词汇

Environmental quality 环境质量Acid rain酸雨 Sulfur dioxide二氧化硫Nitrogen oxide 氧化氮Automobile exhausts汽车尾气Infectious diseases传染病Waterborne diseases通过水传播的疾病 Carbon dioxide二氧化碳Environmental disturbance环境破坏 Aquatic life 水生物 Detection limits 检出限Qualitative 定性的Quantitative定量的Characterization 表征性能描写Unpleasant odors 难闻的气味Trace l level 痕量微量Carbon oxide碳化物 Carbon monoxide 一氧化碳Carbon dioxide 二氧化碳Sulfur oxide 硫化物 Sulfur dioxide二氧化硫 Sulfur trioxide 三氧化硫Nitrogen oxide 氮化物 Nitrous oxide一氧化二氮 Nitric oxide一氧化氮 Nitrogen dioxide 二氧化氮Ethane 乙烷 Propane 丙烷Photochemical oxidants 光氧化剂 Ozone臭氧 Aldehydes 乙醛 Sulfate salts硫酸盐 Hydrogen sulfide 硫化氢Ammonia氨气 Sulfur acids 硫酸 Nitric acid 硝酸 Primary air pollutant一次污染物Second air pollutant二次污染物Biofiltration生物过滤 Volatile organic compounds挥发性化合物Trickling filter滴滤器 Municipal sewage treatment plant市政污水处理厂 Wastewater treatment plant污水 处理厂 Rendering plant 炼油厂 Ethanol 乙醇 Biodegradation 生物降解 Bioremediation 生物治理 Suspended solid（SS）悬浮颗粒 物 Volatile suspended solid(VSS) 挥 发性悬浮颗粒物 Biochemical oxygen demand (BOD)生化需氧量 Heavy mental重金属 Domestic sewage 生活废水 Chemical oxygen demand (COD) 化学需氧量 Sewage 污水、废水 Microorganism微生物 Microbe微生物 Bacteria(复数) Bacterium(单数)细菌 Oxidizer氧化剂 Oxidant氧化剂 Dissolved oxygen溶解氧 Residence time 停留时间 Eutrophic lake富营养化的湖泊 Sanitary sewage 生活污水 Aeration tank 曝气池 Sedimentation tank 沉淀池 Eutrophication 富营养化 Adsorption 吸附 Activated carbon 活性炭 Activated sludge活性污泥 Coagulation 絮凝、凝固 Flocculation 混凝 Sedimentation 沉淀、沉积 Hydrophilic 亲水的、吸水的 Oxidizing agent 氧化剂 Reverse osmosis 反向渗透 Membrane膜 Groundwater地下水 Surface water 地表水 Aluminum sulfate 硫酸铝 Screening （用拦污栅）隔离 Turbidity 浊度，浑浊性 Colloidal胶体 Chlorine dioxide 二氧化氯 Ultraviolet light 紫外线 Limestone 石灰石 Incinerator 焚烧炉 Hazardous waste 危险废物 Refuse垃圾、废物 Environmental protection agency 环保部 Hydrogen sulfide 硫化物 Decontamination 净化，消 除……的污染 Aerobic 需氧的 Anaerobic 厌氧的 Decibel meter 分贝仪 Subsonic 亚声速的 Supersonic 超声速的 Muffler消声器 Ecological disruptions 生态破坏 Aquatic ecosystem 水环境系统 Environmental impact assessments环境影响评价 Kinetics 动力学 Steady-state 稳态的 Point source discharge点源排放 Receiving water收纳水体 Nitrogen oxide 氮氧化物 Photochemical oxidant 光化学氧 化剂 Carbon monoxide一氧化碳 Coliform bacteria 大肠杆菌

生物工程生物技术专业英语翻译(二)

第二章生长与代谢的生物化学 2.1 前言 一个微生物以生产另一个微生物为目的。在某些情况下，利用微生物的生物学家们希望这样的情况能够快速频繁的发生。在另外一些产物不是生物体自身的情况下，生物学家必须对它进行操纵使微生物的目标发生变化，这样以来，微生物就要努力的挣脱对它们繁殖能力的限制，生产出生物学家希望得到的产物。生物体的生长过程及其生产出的各种产物与微生物代谢的本质特点是密不可分的。 代谢过程是两种互相紧密联系又以相反方向进行的活动过程。合成代谢过程主要是细胞物质的生成，不仅包括构成细胞的主要组成物质（蛋白质、核酸、脂质、碳水化合物等等），同时也包括它们的前提物质——氨基酸、嘌呤与嘧啶、脂肪酸、各种糖与糖苷。合成代谢不是自发进行的，必须由能量所推动，对大多数微生物来说，是通过一系列的产能分解代谢过程来供给能量。碳水化合物分解为CO2和水的过程是最为常见的分解代谢反应，然而微生物以这样的方式还能够利用更大范围的还原性含碳化合物。分解代谢与合成代谢所有微生物生物化学的基础，可以从两者的平衡关系或者分别对它们进行讨论。 实际中，我们要有效的区分那些需要空气中的氧进行需氧代谢的生物与那些进行厌氧代谢的生物。还原性含碳化合物与O2反应生成水和CO2，这是一个高效的放热反应过程。因此，一个进行需氧代谢的生物要使用一小部分底物进行分解代谢以维持某一水平的合成代谢，即成长过程。对于厌氧型生物，其底物的转化的过程基本上是一个不匀称的反应（氧化还原反应），产生很少的能量，因此，大部分底物都要被分解从而

维持一定水平的合成代谢。 在生物体中这种差别能够明显的体现出来，比如酵母，它属于兼性厌氧生物，即它可在有氧条件下生长也可在无氧环境下生存。需氧酵母使糖以同样的速度转化为CO 2和水，相对产生高产量的新酵母。而厌氧条件下，酵母菌生长缓慢，此时酵母被有效的转化为酒精和CO 2。 2.2 代谢与能量 分解代谢与合成代谢间的有效联系在于，各种分解代谢过程促进少量反应物的合成，而后又被用来促进全面的合成代谢反应。在这种重要的中间产物中，其中最为重要的是ATP ，其含有生物学家所说的“高能键”。在ATP 分子中，酐与焦磷酸残基相联。高能键在水解过程中所产生的热量就被用来克服在其形成过程中需要摄入的能量。像ATP 这类分子，为细胞提供了流通能量，当将ATP 用于生物合成反应时，其水解产物为ADP （腺苷二磷酸）或者某些时候为AMP （腺苷一磷酸）：（反应式） 仍含有一个高能键的ADP 通过腺苷酸激酶反应也可生成ATP ：（反应式）。 磷酸化作用是生物体中普遍的反应，通常由ATP 作用而发生。 经过磷酸化生成的物质通常比最初的化合物更具有反应活性，用无机磷酸进行磷酸化反应是无法进行的，因为，平衡反应式的相反方向生成大量的水（55M ）。 细胞的“能量状态”认为是由占有优势的组分：ATP 、ADP 、AMP 作用形成的。为了给出一个量值，Daniel Atksirson 提出了“能荷”这个概念，定义一个细胞的能荷为： 在“满荷”细胞中，仅含有ATP 一种腺嘌呤核苷酸，它的能荷值定义为 1.0。如果三种核苷酸的量相等，即ATP=ADP=AMP ，则细胞的能荷为ATP+0.5 ADP ATP+ ADP+AMP

环境工程专业英语钟理_翻译

第一单元环境工程 这本书主要关于什么？ 这本书的目标是使工程和科学的学生了解学科间的研究环境问题：它们的起因，为什么它们被关注，我们怎么控制它们。这本书包括： ●描述环境和环境系统意味着什么 ●关于环境破坏基础原因的信息 ●理解环境问题本质和能够定量计算它们所必要的基本科学知识 ●目前运用在水,空气,污染问题的环境控制技术的状况 ●我们目前在很多关于理解和控制人类活动、自然之间复杂相互作用的科学知识上存在着相当大的空白●很多环境问题能运用目前的技术消除或减少，但因为社会缺少意愿这么做或在很多例子中因为缺乏资源去这样做，这些环境问题没有被处理 一些重要的定义： 在这本书中，它们第一次被使用，定义被以大写或印刷成黑体字的形式展示 环境是围绕在我们周围的物质生命的栖息地，在这儿我们能看到,听到,触摸,闻到,和品尝到 系统依据韦氏字典,被定义为“一组或一系列能形成一个整体或者有机整体的相互关联的事物”，例如，太阳系统，灌溉系统，供应系统，世界和宇宙。 污染被定义为“在大气，水或土地中的物质的，化学的或生物的特性的不合意的改变，这一改变有害地影响人类或其它生物的健康，生存，或活动”。 当改进环境质量的目标被用来改进人类福利，“环境”一词扩展成包括所有的社会，经济和文化方面的容。这一扩展在许多真实情况下是不可行的以及在一本被设计为一学期课程的教科书中也是不实际的。我们对环境问题的考察因此限于我们对“环境”的定义。 系统的相互作用 许多不同的环境问题都与水，空气或土地系统有关联。许多这些问题都只适用于这些系统中的一个，这为这些种类中的细目分类提供了充分的理由。这样的分类也更有用于及易于理解一个系统的相关问题。而且，这样做是明智的，这是因为由于管理上的和行政上的原因，这些有关空气污染，水供应，废水处理和固体废物处理的子域通常由政府机构分别处理。 很遗憾的是，很多重要的环境问题不仅仅限制于空气，水或土地系统，还包括系统间的相互作用。现在举个例子，酸雨问题起源于从发电站烟囱，冶炼厂和汽车尾气中向大气排放的含硫二氧化物和氮氧化物。接着这些气体由气流运输到广阔的区域，降雨“将它们洗去”，产生了有害于水生生命，森林和农作物的酸雨。两个有关于系统间相互作用引起的环境问题有：空气中的二氧化碳的增加的全球问题，及通常具有地域性质的酸雨问题。 环境问题 许多对我们生活标准的主要改进能被归因于科学和技术的运用。这里举一些例子，你能想出其它例子吗？ ●生产更多及更好质量的食物 ●创造能避免极端环境的保护所和生存空间 ●快速和可靠的运输方法的建立 ●各种交流系统的发明 ●代替人类和动物体力的机器的发明 ●安全水的供应和废物处理 ●对很多传染疾病的消除 ●通过在发达国家运用改进的水技术对大部分水传染的疾病的消除 ●通过更好的生产力（带来的）闲余时间的有效性，为文化的，娱乐的活动提供机会。 ●避免例如洪水，干旱，地震，火山爆发的自然灾害的最坏影响 然而，通过这些改进，已经带来了不良的负面影响，例如耕地的丧失，消失的森林，环境的污染和

安全工程专业外语翻译

The major contributors in component technology have been the semi-conductor components． （译为“起主要作用”，不译“主要贡献者”。） There are three steps which must be taken before we graduate from the integrated circuit technology. （译为“完全掌握”，不译“毕业于”。） The purpose of a driller is to holes. （译为“钻孔”） A single-point cutting tool is used to cut threads on engine lathes. （译为“车”） The major contributors in component technology have been the semi-conductor components． （译为“起主要作用”，不译“主要贡献者”。） There are three steps which must be taken before we graduate from the integrated circuit technology. （译为“完全掌握”，不译“毕业于”。） The iron ore used to make steel comes from open-pit and underground mines. （译为“炼钢”，不译“制造刚”。） An insulator offers a very high resistance to the passage through which electric current goes. （译为“很大阻力”，不译“高阻力”） Mater can be changed into energy, and energy into mater. 物质可以转换为能，能也可以转化为物质。 The best conductor has the least resistance and the poorest has the greatest. 最好的导体电阻最小，最差的导体电阻最大。 If A is equal to D, A plus B equals D plus B. 若A=D，则A+B=D+B。 The first electronic computers used vacuum tubes and other components, and this made the equipment very large and bulky. 第一代电子计算机使用真空管和其他元件，这使得设备又大又笨。 Oxidation will make iron and steel rusty. 氧化作用会使钢铁生锈。 The cost of such a power plant is a relatively small portion of the total cost of the development. 这样一个发电站的修建费用仅占该开发工程总费用的一小部分。 The resistance of the pipe to the flow of water through it depends upon the length of the pipe, the diameter of the pipe, and the feature of the inside walls（rough or smooth）。 水管对通过的水流的阻力取决于下列三个因素：管道长度、管道直径、管道内壁的特性（粗糙或光滑）。Heat from the sun stirs up the atmosphere, generating winds. 太阳发出的热能搅动大气，于是产生了风。 In general, all the metals are good conductors, with silver the best and copper the second. 一般来说，金属都是良导体，其中以银为最好，铜次之。 The world of work injury insurance is complex. 工伤保险是复杂的。 Any substance is made of atoms whether it is a solid, a liquid, or a gas. 任何物质，不论是固体、液体或是气体，都是有原子组成的。 In the absence of force, a body will either remain at rest, or continue to move with constant speed in a straight line. 无外力作用，物体则保持静止状态，或作匀速直线运动。 A wire lengthens while it is heated. 金属丝受热则伸长。 Practically all substances expand when heated and contract when cooled. 几乎所有的物质都是热胀冷缩的。