Product news All eyes on ATP: microbial ATP to assess bacterial and pathogen contamination

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1 INDUSTRY NEWSLETTER Drinking water Dear reader, In this issue Many countries and international organizations have created water quality guidelines for potable water supplies, thereby defining standards for treatment processes to meet. Yet, the almost continuous identification of emerging contaminants in our fresh-water supplies results in ever-tightening water quality requirements that go beyond the presence of dissolved salts in the raw water. Microorganism contamination, for example, will be identified or detected in an early stage, creating a path to more efficient disinfection processes. Product news All eyes on ATP: microbial ATP to assess bacterial and pathogen contamination Process Water quality data are undoubtedly influenced by analysis frequency, sampling location, analytical methods and last but not least, maximum contaminant levels. On-line monitoring is a piece of the technology puzzle and key to providing process transparency. Hach s extended range of water analyzers allows you informed decision making based on continuous data. On-line colorimetry for determination of water quality indices: an overview Heavy/trace metals We invite you to take a closer look at our latest developments in this area, either in this newsletter or on our website Single and multi-parameter determination of trace metals With analytical regards, Hach Read more: Discover the On-line Analyzers Suite on

2 PRODUCT NEWS Microbial ATP as the common denominator in bacterial and pathogen contamination Using the well-known firefly assay, the EZ 7300 On-line Microbiology Analyzer is a unique alternative to current manual analysis methods for assessing microbiology in water, providing timely and accurate data. The traditional heterotrophic plate count (HPC) for the evaluation of the total number of bacteria in a sample of drinking water takes days of incubation. By the time the analysis results are known, the water is already consumed, if not on its way in the distribution network. Clearly, traditional lab testing does not provide process transparency and is ineffective for the protection of consumers health. Adenosine triphosphate (ATP) testing has become a popular alternative to these time-consuming lab methods. ATP testing is important in the food & beverage industry as it helps to assess the quality and hygiene of the water used in food processing. For drinking water production, ATP testing provides an objective basis for actions against sudden changes in bacterial load. The newly developed EZ 7300 Series are designed as automatic on-line analyzers to assess microbial contamination in a production area or treatment facility where the sample is presented to the analyzer from a pressurized line. In addition, the grab sample option allows laboratory staff to use the analyzer as a benchtop instrument and run samples manually. With a LOD of 0.05 pg/ml ATP, the on-line analyzer is capable of detecting very low levels of bacteria (0.05 pg ~ 50 E. coli sized bacteria) The quantification of the different ATP portions total, intracellular and free ATP allows to follow closely abnormalities in microbial levels and biocide dosing. The EZ 7300 uses proprietary enzymatic reagents from ATP experts Promega, that show superior stability even in the presence of free chlorine levels up to 2 mg/l. EZ 7300 for drinking water applica ons Complying with ASTM D standard test method Detection of intracellular, extracellular and total ATP No bias from the composition of the growth medium such as with plate counting Rapid measurement: minutes Low cost of analysis relative to a large number of results Low limit of detection (LOD): 0.05 ng/l (0.1 pm) ATP Low maintenance, easy replaceable Promega reagent kit More informa on Request your copy of the technical brochure and find out more about the EZ 7300 On-line Microbiology Analyzer HACH Industry Newsletter Drinking Water 03

3 Pretreatment Control primary disinfection and DBPs: Connecting critical process parameters The quality of the distributed water is of paramount importance as it concerns human health. Operators are facing numerous regulations versus practical limitations of their treatment facilities but must satisfy disinfection requirements by using either chlorination or chloramination with minimal DBPs. On-line monitoring of multiple critical parameters is now possible for both processes, by means of a single stand-alone water analyzer of the EZ Series. Disinfection by chlorine is known to introduce a number of side reactions with organic and inorganic species, that not only reduces the availability of chlorine but also produces several byproducts known as DBPs. Chloramination was introduced as an alternative method of disinfection involving the addition of ammonia before or after the addition of chlorine to produce primarily monochloramine (NH 2 Cl). The weight ratio of free chlorine to ammonia directly affects the type of chloramine formed, which can t be controlled by the measurement of free chlorine or even free ammonia alone. The risk of overfeeding or underfeeding chlorine in chloramination in this case is not far-fetched. Combining multiple critical parameters in one single platform gives us the following options: To measure total + free chlorine levels, the analyzer runs a double analysis cycle based on the established DPD (N,N-diethyl-pphenylenediamine) colorimetric method. Chloramine can then indirectly be estimated by calculation. To measure monochloramine directly, the analyzer runs a direct measurement by Berthelot. Free and total chlorine can then be determined in a separate, colorimetric analysis cycle. HACH Industry Newsletter Drinking Water 04

4 Process EZ 1000 Series: Automatic, on-line colorimetry for determination of water quality indices Drinking water quality criteria often require the analysis of a large set of physico-chemical and biological parameters conducted by an in-house laboratory of the local water authority or external certified laboratories. The continuous, on-line monitoring of a set of target parameters can be an added value to your operations to reduce lab workload, or in terms of process control, provide more real-time insight on critical points in your production plant. The EZ 1000 Series have been designed to monitor 10 essential water quality indices, which are related not only to taste and appearance but also to safety and disinfection. Generating up to six readings an hour for most parameters, the EZ 1000 Series provide almost real-time results on current process conditions. The built-in panel PC assures full integration and communication with industrial production sites and corporate networks. Short specifica ons Total Hardness Chloride Chlorine (free, total) Color Fluoride (by ISE) APHA 2340 (C) APHA 4500-Cl (B) APHA 4500-Cl (G) APHA 2120 (B) APHA 4500-F Several ranges available Several ranges available mg/l Pt-Co Several ranges starting from 1 mg/l F - 5 µg/l / Depending 0.5 mg/l 10 µg/l 10 Pt-Co 0.02 mg/l / 15 minutes Continuous HACH Industry Newsletter Drinking Water 05

5 On-line, automa c colorimetry The EZ Series of On-line Colorimetric Analyzers have already served in a countless industrial, municipal and process water applications. The flexible analyzer mainframe allows a perfect on-line duplicate of most standard/laboratory wet-chemical methods, with outstanding precision and accuracy. At the heart of the colorimeter there is a compact photometer assembly developed especially for the EZ Series. Consumption of reagents is reduced by low volume analysis, yet high sensitivity is assured by a long optical path length. An external multiplexing unit makes it possible to monitor up to 8 streams sequentially, reducing the cost per sampling point. Simplified opera on At Hach we are convinced that an analyzer s analytical performance should go hand in hand with trouble-free operation, minimal maintenance and easy data exchange. The compact mainframe packed with a robust architecture and high quality components requires little maintenance and inspection. Smart features such as automatic calibration/validation and cleaning are embedded in the controller software and minimize operator intervention. Automatic internal (or external) dilution is another possibility, with the software monitoring result output and adjusting measuring range if necessary to compensate for wide variation on a parameter. Short specifica ons CONTINUED Manganese Iron II/III (total) Nitrate / Nitrite Ammonia Aluminium N.A. / Formaldoxime method APHA 3500-Fe (B) APHA 4500-NO3 (H) APHA 4500-NO2 (A) APHA 4500-NH3 (Berthelot) N.A. (Nessler) N.A. / Pyrocatechol method 0-1 mg/l Mn mg/l Fe 2+ /Fe µg/l NO µg/l NO mg/l N (Berthelot) mg/l N (Nessler) µg/l Al 3+ 5 µg/l 5 µg/l 0.2 µg/l / 2 µg/l (NO 2) 5 µg/l (B) / 10 µg/l (N) 10 µg/l 15 minutes 25 (B) / 10 (N) minutes HACH Industry Newsletter Drinking Water 06

6 Emerging pollutants EZ 6000 Series: single and multi-parameter measurement of trace metals in raw water Many of the trace metals are chemical elements which are a necessary part of animal and human physiology. Heavy metals such as mercury, cadmium, arsenic, chromium, thallium and lead, with a relatively high density and toxic at low concentrations, often originate from industrial activity. Excessive concentrations of these in surface water or ground water can carry over to the water treatment stage, if not removed. The analytical technology behind the EZ 6000 Series is a sensitive electrochemical technique called Anodic Stripping Voltammetry (ASV). Basically it involves a preconcentration of the analyte of interest, the metal, to the surface of an electrode, followed by an selective oxidation from the same electrode during the stripping phase. The exact configuration of the ASV cell depends on the choice of working electrode and the priority metals for your application. At AppliTek we know that proper measurement of some metals may be challenging, given the presence of various chemical states and forms in natural water or waste water. This is especially true for arsenic and mercury. The EZ 6000 add-on digestion unit has been designed specifically for samples with higher organic contents, suspended particles and changing composition. The sample is mixed with concentrated acid and heated in a compact, built-in oven, turning all dissolved, complexed and adsorbed metal forms to free ions. This design principle adds to analytical performance and trouble-free operation of the on-line analyzer. Our Application department will gladly help you with finding the right solution for your target metals. Standard EZ 6000 mainframe with the add-on sample digestion unit. Overview Trace elements CADMIUM + LEAD + COPPER + ZINC CADMIUM + LEAD COPPER + ZINC ARSENIC + MERCURY ARSENIC (TOTAL) + ARSENIC (FREE) SELENIUM Typically 1 µg/l (range µg/l) ANTIMONY MANGANESE NICKEL CHROMIUM HACH Industry Newsletter Drinking Water 07

7 Organics Cost-effective determination of organic carbon content in surface water intake In drinking water production, Total Organic Carbon is often used as a non-specific measure of the water quality. The presence of TOC has a direct effect on disinfection byproducts that are formed during disinfection. On-line monitoring of TOC levels in the raw water empowers operators to take key decisions in the process and optimize TOC removal. Used in wide array of applications, the EZ 7100 Series run the established hot-aerosol UV/persulfate method conform with standard methods ISO 8245, APHA 5310C, ASTM D4839 and USEPA Accordingly, a precise volume of sample is transferred to the UV reactor where acid is dosed to facilitate the removal of inorganic carbon. At ph 2 the inorganic carbon is converted to carbon dioxide gas which is stripped out from the sample liquid using a sparge gas. Inside the UV reactor, the combination of sodium persulphate, heat and dual-wavelength UV radiation all oxidize the organic carbon to CO 2, which will be pushed to the non-dispersive infrared detector by the mass flow controlled carrier gas. A membrane air dryer assures a clean, dry gas for delivery to the infrared detector. The CO 2 generated from the oxidation process is proportional to the TOC content of the sample. A unique feature of the EZ 7100 is the possibility to use the discontinuous batch mode instead of the standard continuous TOC method. From our experience most customers do not need results being generated every 5 minutes, which comes with a considerable consumable price tag at the end of the month. Instead, you can set a specific analysis cycle/hour in function of your needs or a specific process, get the results you require and economize on reagents and overall maintenance. Analysis of ground water & surface water The Total Organic Carbon configuration of the EZ 7100 Series is a measure of the non purgeable organic carbon (NPOC), while the volatile carbon (VOC) and the purgeable carbon (POC) are stripped out and lost for analysis. Yet, in most surface and ground waters the fraction of POC is negligible. Alternatively, if significant amounts of volatile compounds are present, the analyzer can be configured to measure Total Carbon (TC) levels by omitting the inorganic stripping phase. For surface water/ ground water applications, we recommend a selection of the following measuring ranges: 0-5, 0-10, 0-20, or mg C/L. All TOC analyzers come calibrated in function of the required measuring range. A number of optional filtration systems with automatic blowback are available to assure trouble-free sampling. At the heart of the EZ 7100 is a compact UV reactor with dual wavelength UV lamp. Advanced features High recovery rate with dual-wavelength UV reactor Possibility to set discontinuous mode Smart features: automatic calibration, validation and cleaning Unique range-specific solid state IR detector with automatic zero calibration Correlation to COD or BOD levels possible Up to eight (8) sampling points possible Incorporated industrial PC with AppliTek controller software Extended data communication and exchange features HACH Industry Newsletter Drinking Water 08

8 INDUSTRY NEWSLETTER Drinking water Published by AppliTek NV - Venecoweg Nazareth - Belgium