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THE CARBONC O M PA N YA JACOBI CARBONSC O M PA N YTECHNICAL BULLETINACTIVATED CARBON APPLICATIONSFor Drinking Water ProductionWater is an essential element of life: it accounts for 70% to 80% of the weight of a human being. The quality of wateris an important parameter that affects all aspects of the well-being of ecosystems and mankind, from human health, tofood production, economic activities and biodiversity.Today, more than ever, water resources are under pressure: demographic growth, intensive agriculture, industrialactivities, and climate change, are weakening the prime natural resource of our planet. No source of this vitalresource is spared: groundwater, rivers and oceans are all threatened by pollution and are universally of concern ofinternational authorities. The nature of the pollutants are diverse. They can be naturally occurring (taste and odors,algae toxins, organic matter) or related to human activities (hydrocarbons, heavy metals, pharmaceuticals, pesticides,surfactants, endocrine disruptor). The contaminations can be both seasonal or persistent.While aquatic pollutants are known and classified, their effects – especially in combination - are still questionable,especially when it comes to industrial chemicals. To prevent the population to be exposed to these contaminants indrinking water, operators are required to remove them, and to comply with more and more stringent regulations.One of the easiest ways to do this, especially in case of temporary pollution, is to use Powdered Activated Carbon(PAC). Activated carbon is a very reliable adsorbent with a wide spectrum of effectiveness on numerous pollutants.However, there are many types of powdered activated carbons. Although, activated carbons appear merely as aninnocuous black solid, each one has a specific characteristics with an affinity to certain pollutants.This paper will describe the diversity and specificity of Jacobi’s activated carbons intended for drinking watertreatment, and provide guidance on their relative performances against the following pollutants: Organic matter Pesticides Taste and Odors Emerging pollutantsThis paper is also to be used as a guide for: Selecting the activated carbon which will be appropriate for treating the target pollutant(s); Determining the efficiency of the activated carbon already installed in a plant in relation to existing regulationsand emerging pollutants.Our aim is to contribute to water quality control whilst optimizing treatment plant operatingcosts.

Technical Bulletin: Raw Water TreatmentOrganic matter (OM) removalMany natural organic substances are present in groundwater or surface water, such as humic substances, hydrophilicand carboxylic acids. Most are related to the decomposition of plants and animals living in the catchment area orin the river itself. Organic matter can also be related to urban activities. This great diversity is also reflected in thechemical and physical properties of the pollutant.Each step of the drinking water treatment process contributes in the elimination of part of the organic matter,especially the coagulation/flocculation/settling phase. However, the removal efficiency may be insufficient to reachthe target required by regulations (2 mg/L maximum of TOC in most countries), in particular when the concentrationof OM in raw water is high.In this case, adsorption is a particularly efficient treatment to reduce the organic matter concentration, as illustrated bythe test results below:Organic matter removal efficiencies- PAC from the AquaSorb range 60%50%40%30%20%10%0%CP1BP2CB5-MW CB3-MW CB1-MW 5000PPAC dosage: 20 mg/lPAC dosage: 50 mg/lTrials on Cher river raw water done by PICA Jacobi Lab in Vierzon (France) in 2011Kinetic test at 10 minutes of contact timeMeasurement of the optical density at 254 nm (initial OD 0,08)As can be seen, the choice of the PAC type to use will depend on the expected removal efficiency and economicfactors in implementing the use of the grade selected.

Technical Bulletin: Raw Water TreatmentPesticides removalPesticides are a perpetual problem in water treatment. They are often present in raw water sources, varying intheir nature and concentration over different periods of time. Worldwide water treatment plants must comply withincreasingly strict regulatory limits for pesticide levels in the treated water supplied to the network.Generally, activated carbon is the only technology available in the drinking water treatment process that is able toefficiently remove pesticides.The graph below illustrates the removal efficiency of different activated carbons on atrazine, a pesticide widelyrecognized as an indicator of adsorption characteristics for this type of pollutant.Atrazine removal efficiencies- PAC from the AquaSorb range 100%80%60%40%CB5-MWCP1BP2PAC dosage: 20 mg/lCB3-MW CB1-MW 5000PPAC dosage: 50 mg/lTrials on Cher river raw water done by PICA Jacobi Lab in Vierzon (France) in 2011Kinetic test at 10 minutes of contact timeIn the presence of organic matterThe nature of pesticides is incredibly diverse, and they vary greatly according to their use, composition andphysicochemical properties. However, all types generally have an affinity for adsorption by activated carbon.

Technical Bulletin: Raw Water TreatmentThe table below provides guidance to the relative level of affinity between selected pesticides and activated carbon.Compounds are classified with respect to the reference pesticide, atrazine, for which activatedcarbon affinity is indicated by two drops “ ”.The higher the number of “ ” (drops), the higher the affinity level.CompoundDeveloped formulaFamilyUseMolecularSolubilityweight (g/mol)(mg/l)Log Kow*molecule tude of thebe inOrganochlorinated rbicide84280 sHerbicide216332,3

Technical Bulletin: Raw Water TreatmentCompoundDeveloped formulaFamilyUseMolecularSolubilityweight (g/mol)(mg/l)Log Kow*molecule toBAMBenzamides226694Aptitude of thebe diazones cide19181,5ChlordeconeOrganochlorinated e)DEDIA hylterbuty-Triazines///lazineDIA (Deisopropy-TriazinesHerbicide1742081,2latrazine)

Technical Bulletin: Raw Water TreatmentCompoundDeveloped formulaFamilyUseMolecularSolubilityweight (g/mol)(mg/l)Log Kow*molecule titude of thebe DiuronSubstituted ureaHerbicide233422,9Endosulfan (α)Organochlorinated icide315453,7GlyphosateAmino-phosphonates Herbicide16912,000-4,1HCB (Hexachloro-Organochlorinated uted ureaHerbicide206552,5LindaneOrganochlorinated Insecticide29173,7products

Technical Bulletin: Raw Water TreatmentCompoundDeveloped formulaFamilyUseMolecularSolubilityweight (g/mol)(mg/l)Log Kow*molecule toLinuronSubstituted ureaHerbicide24981Aptitude of thebe etonesHerbicide329165 riazinesHerbicide2251303,0

Technical Bulletin: Raw Water TreatmentCompoundDeveloped formulaFamilyUseMolecularSolubilityweight (g/mol)(mg/l)Log Kow*molecule toTerbutryneTriazinesHerbicide24122Aptitude of thebe ,4 DArylo-acidsHerbicide22145,0002,6(*) octanol/water distribution coefficientNote : The results described above are based on laboratory studies conducted by Jacobi Carbons and variousindependent laboratories. Efficiencies indicated in the tables are provided in a qualitative format.It is important to recognise that adsorption capacities depend on numerous factors, including:Resource qualityType of treatment processType of compound to be eliminatedConcentration of compound to be eliminatedLevel of reduction requiredPresence of other compounds (which may compete with the adsorption of target compounds)As each case is unique, please do not hesitate to contact your Jacobi Carbons sales representative. Jacobi Carbonshas considerable technical resource capability to assist in the selection of the most suitable activated carbon toachieve the treatment objectives required. Our AquaSorb range is extensive and includes products from a varietyof raw materials and activation methods. In addition, our manufacturing plants are able to produce materials withspecific properties to optimize the treatment outcomes.

Technical Bulletin: Raw Water TreatmentTaste & odor removalIn recent years, the intensity and frequency of taste and odor problems in drinking water have increased throughoutthe world. Beyond the aesthetic problem for the consumer, this also invariably creates uncertainties about the qualityand safety of water.The compounds responsible for taste and odor problems can have an anthropogenic (industrial or municipaldischarges) or biological origin. In the latter case, they are produced by microscopic organisms such ascyanobacteria.The two most common compounds are geosmin and 2-methylisoborneol(MIB). Geosmine, which has an earthy smell, is often produced by planktoniccyanobacteria (suspended in water). MIB, which has a musty smell, is mostoften produced in biofilm developing on rocks, aquatic plants and sediment.These compounds are detected by human olfactory cells at very lowconcentrations, even in the range of a few ng/l.It has not yet been determined if any such risk is posed by geosmin and MIB on human health and the environment.Furthermore, it is difficult to predict the occurrence of such phenomena as triggering factors are poorly known.Conventional treatments such as oxidation do not necessarily achieve the destruction of these compounds to levelsbelow this very low detection limit, hence the implementation of the use of activated carbon. The results presentedbelow are based on scientific data established and published by independent laboratories, operated by theAustralian Water Quality Center.MIB removal efficiencies- PAC from the AquaSorb range -90%80%70%60%50%40%30%20%CP1BP2CB3-MWPAC dosage: 10 mg/lCB1-MW5000PPAC dosage: 40 mg/lCompiling of several test results done on tap water spiked at a target concentration of 100ng/L of MIBKinetic test at 20 minutes of contact timeIn presence of organic matter

Technical Bulletin: Raw Water TreatmentThe most efficient reduction of MIB requires a predominately mesoporous activated carbon. This observation isconsistent with the size of the molecule to be removed.However, the choice of the PAC type to use depends of the expected removal efficiency and economy prevailing inthe treatment process.As shown below, the adsorption of geosmin is slightly improved over that of MIB.MIB and geosmin removal efficiencies- PAC from the AquaSorb range 0PPAC dosage: 10 mg/lCB3-MWCB1-MW5000PPAC dosage: 40 mg/lTrials done by AWQC on tap water spiked at target concentrations of 100ng/L of MIB and geosminKinetic at 20 minutes of contact timeIn the presence of organic matterA similar test has shown that doubling the contact time does not have much influence. The removal of MIB is slightlyincreased, but for geosmin, removal efficiency remains the same. We can therefore deduce that a contact time ofapproximately 20 minutes is sufficient to reduce these compounds to acceptable levels.

Technical Bulletin: Raw Water TreatmentEmerging pollutantsThe presence of active pharmaceutical ingredients, radio-opaque substances and endocrine disrupting chemicals inraw water sources is a relatively new emerging issue in relation to drinking water quality. German studyA study for the removal of micro pollutants has been carried out by the Biberach University of Applied Science.Powdered activated carbon has been used to remove pharmaceuticals and radio-opaque substances from water in aplant in southern Germany. AquaSorb CB1-MW has been tested and was proven to be suitable for the removal ofthese substances, as shown in the graph below.The graph shows the concentrations of pharmaceuticals which were found to be present in an amount higher than thedetection limit for at least one of the omycinDehydrato- letwater

Technical Bulletin: Raw Water TreatmentThe removal rate for all substances listed is higher than 50% and in some cases as high as 97%.For the substances which were present at the highest concentrations a comparison to the reference carbon was made.The results are shown in the figure below:Removal rates for four pharmaceuticals- PAC dosage: 10 mg/L10090Removal Rate b CB1-MWDehydrato-Erythromycin ASulfamethoxazoleReference carbonAs for radio-opaque substances, the investigation has been limited to iodine containing substances because theyare the most present and most persistent members of this substance group in water. The figure below shows the inletconcentrations in the pilot ant(ng/L)Concentra)onsofradio- ‐opaquesubstancesintheinletwater

Technical Bulletin: Raw Water TreatmentRadio-opaque substances are highly polar molecules in comparison to the pharmaceuticals investigated within thisstudy. Therefore they show significantly lower removal rates. Ionic substances additionally showed lower removalrates than the non-ionic substances which were included. For all substances the removal rate can be enhancedby higher carbon dosage rates. The differences of the removal rates and a comparison to the reference carbonsperformance are shown in the figure below.Removal rates for several radio-opaque substances10090Removal rate (%)80706050403020100IohexolIomerprolAquaSorb CB1-MW (10 mg/L) IopamidolIopormideReference carbon (10 mg/L)Amidotrizoic acidAquaSorb CB1-MW (20 mg/L)Swiss studyOther trials have been performed by Ecole Polytechnique of Lausanne (Switzerland) on the following 21 micropollutants :numéro CASng/L enmoyenneLipid regulators ticalsAntiepilepticdrugsAnalgesicsBeta BlockersSubstancesCarbamazepinStructure de la moléculepoidslog Kowmoléculaire

Technical Bulletin: Raw Water iocides/ PesticidesX-Ray tryn886-50-010241.363.74AlgicidesThe removal efficiencies are shown graphically below:Removal rates for different pharmaceuticalsand radio-opaque substances- PAC dosage: 10 mg/L - contact time: 30 mins1009080Removal rate (%)70605040302010AquaSorb rateBezafibrate0Reference carbonAquaSorb CB3-MW proved to be the most efficient activated carbon to remove these compounds.

Technical Bulletin: Raw Water TreatmentThe study also shows that the increase of the PAC dosage has a better effect on the removal efficiency than theincrease of contact time, as illustrated in the graph below:Effect of the increase of contact time of PAC dosage- AquaSorb CB1-MW 605040302010030 minPAC dosage: 10 mg/L60 minPAC dosage: 20 mg/LAs each case is unique, please do not hesitate to contact your Jacobi Carbons sales representative. Jacobi Carbonshas considerable technical resource capability to assist in the selection of the most suitable activated carbon toachieve the treatment objectives required. Our AquaSorb range is extensive and includes products from a varietyof raw materials and activation methods. In addition, our manufacturing plants are able to produce materials withspecific properties to optimize the treatment outcomes.For more information or to contact Jacobi visit: www.jacobi.netNOTICE Due to the progressive nature of the Jacobi Carbons Group and the continually improving design and performance of our products,we reserve the right to change product specifications without prior notification. The information contained in this datasheet is intended toassist a customer in the evaluation and selection of products supplied by Jacobi Carbons. The customer is responsible for determining whetherproducts and the information contained in this document are appropriate for customer’s use. Jacobi Carbons assumes no obligation or liabilityfor the usage of the information in this datasheet, no guarantees or warranties, expressed or implied, are provided. Jacobi Carbons disclaimsresponsibility and the user must accept full responsibility for performance of systems based on this data. Copyright 2012. Jacobi, Jacobi Carbons, PICA and the Jacobi and PICA logos are registered trademarks and AquaSorb, EcoSorb,ColorSorb, DioxSorb, AddSorb, ReSorb, PICACTIF, PICAPURE, PICATOX, PICACARB, PICAGOLD, PICARESP, PICAHYDRO and PICACLEANare trademarks of Jacobi Carbons, all of which may or may not be used in certain -A0412Jacobi Corporate HeadquartersSlöjdaregatan 1SE-39353 Kalmar SwedenTel: 46 480 417550 Fax: 46 480 [email protected] www.jacobi.net

A study for the removal of micro pollutants has been carried out by the Biberach University of Applied Science. .