ph ph/orp On-Line ph/orp Measurement h h h h h h h Measuring Monitoring Controlling Wastewater Treatment Facilities Water Treatment Utilities

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1 ph ph/orp On-Line ph/orp Measurement Measuring Monitoring Controlling Wastewater Treatment Facilities Water Treatment Utilities Neutralization Plants Surface Waters and Groundwater Food Industry Cemical Production Industrial Processes Te ph is one of te most important analysis parameter measured trougout te water, wastewater and many process industries. In te biological treatment of wastewaters, for example, te acidic or alkaline condition of te mixed liquor as an essential influence on te activity of te microorganisms; i.e., continuous on-line ph control is required. Precise and reliable systems for ph monitoring and control are also necessary in drinking water plants and in a variety of industrial process tecnologies. Over te last 45 years, WTW ave been designing and manufacturing precision systems for ph measurement. Ongoing researc and development coupled wit innovative ideas ave resulted in novel metodologies and sopisticated products tat ave set tecnological milestones time and time again. WTW`s tecnical expertise and long experience in tis field are te reason tat our online ph instruments are now recognized for teir excellent performance, reliability and product quality. 212

2 Neutralization / Precipitation / Detoxification ph/orp Measurement Bot in water and wastewater treatment and also in industrial processes te ph is of great practical importance. Te acidity or alkalinity of a process medium plays a key role in many cemical or biological reactions as well as in mecanical/ pysical actions. A number of reactions in precipitation and detoxification, for example may only take place if te ph condition is properly controlled. A misadjusted ph can cause a variety of serious effects, of wic corrosion is te most common in te tecnical world. Terefore, at a rater low or ig ph of a fluid a neutralization treatment often is required. In te area of municipal and industrial wastewater treatment extreme ph conditions may result in te following armful effects: Micro-organisms in biological purification processes are sensitive to acidic and alkaline conditions. Terefore, te ph of te sewage is supposed to be in te neutral range of ph 7. At ph levels of less tan 5 or larger tan 10 te activity of te bacteria practically ceases. ph values of 6.5 and lower result in gradual destruction of metallic materials and mecanical components, and even in damage of te sewer network. Te solubility of many substances varies wit te ph level and temperature. Undesirable and obstructive precipitation of solids may be te result. Today s legislative regulations and environmetal directives in many countries already require tat trade effluents may only be discarged into municipal sewer systems if te ph is between 6.5 and 8.5. For tis reason, industrial discargers, for instance, breweries and dairies, often ave to pretreat its effluent in a neutralization plant. Neutralization, precipitation and detoxification not only require continuous ph measurement but also an efficient ph control system. In less demanding applications, suc as rater stable processes wit slowly canging conditions, a simplified 2-point logic control may be adequate. In many cases, owever, a proportional control loop is considerably more efficient and also economical wit regard to dosing of flocculants or neutralization cemicals. General On-line Features Instrumentation Analyzer Accessories IQ Temperaturductivity Con- ph/orp Oxygen SENSOR NET (D.O.) Liquid Samplers Sample Preparation NEW: IQ SENSOR NET page 254 ph/orp Sensor Assemblies SensoLyt XEROLYT/InTrac ph/orp Monitors TecnoLine EcoLine QuadroLine ph Ex WTW`s complete line of ph/orp instrumentation comprises sensor assemblies, monitors and system components for most different applications. In addition to te well proven SensoLyt sensor assemblies, wic are widely used in wastewater facilities, te product line includes ruggedized sensor assemblies for in-line measurements in industrial processes. Te proven monitors of te 170 and 296 series ave a PIF control algoritm. Te model ph Ex is available for use in explosion-proof zones. Customer Monitoring/ Service Control Station 213

3 ph Proportional Control Depending on te control mode required, te proportional controller will provide eiter a pulse-widt (PW Mode) or pulse frequency (PF Mode) modulated signal. Te control caracteristic is proportional witin a preselected band. Relay Output ON OFF Pulse Period T t ON t OFF t Relative Duty Cycle = ON x 100% T Time (sec.) Pulse Widt Controller (PW) In te PW control mode te pulse widt of te relay output varies wit deviation of te measured value from te limit value; i.e. te relay activation time will be correspondingly longer or sorter. Te total cycle time, referred to as te pulse period T, is te sum of te ON and OFF interval of te relay. Wile te programmed period T remains constant, te relative duty cycle canges as a function of te measured deviation; i.e. te ON/ OFF time ratio varies. Te controller operates wit a duty cycle of 10% to 90%. Wen te deviation of te measured value from te limit value is large, te activation time t ON will be long and te time t OFF sort. As te measured value approaces te limit value, te time interval t ON is reduced; i.e. te relay is activated for a sorter time. Pulse widt controllers are suitable for controlling valves or oter appropriate control devices. Control Parameter: Pulse period T: sec. Relay Output ON t ON Pulse Frequency Controller (PF) A PF controller modulates te pulse frequency of te relay output rater tan te pulse widt of te signal. Depending on te deviation of te measured value from te setpoint, te signal is clocked wit a iger or lower frequency. Wereas te pulse widt (t ON = 0.3 sec.) remains constant, te pulse frequency of te relay output varies in relation to te control parameter. Wen te deviation of te measured value from te limit value is large, te operating frequency is ig. OFF Relative Duty Cycle = Number of Pulses Time (sec.) Time (sec.) As te measured value approaces te limit value, te clock frequency will be reduced. Tis control function is, for example, suitable for dosing pumps. Control Parameter: Frequenz F: pulses/min. 214

4 Proportional band Xp Te proportional band, Xp, is defined as te measuring interval witin wic te proportional controller is operational. Depending on weter te setpoint is entered as an upper or lower limit, te proportional band will start above or below te preset limit value. Te proportional band can be set in increments of 0.1 ph trougout te entire measuring range of te instrument; i.e. at a minimum of 0.1 ph and a maximum of 13.9 ph. ph/orp Measurement Oxygen General On-line (D.O.) Features Instrumentation Upper limit ph/orp If an upper limit Xp/UL is assigned, te proportional control band will start above tis value. Wen te measured value exceeds te selected proportional band, te PW controller will operate at a duty cycle of 100%, and te PF controller at its maximum frequency. Proportional Control (PF) Proportional Control (PW) Temperature Conductivity Controller Output Signal % Limit Value Xp/UL Proportional Band ph Max. Pulse Frequency 50% Pulse Frequency No Output Signal Time Controller Output Signal % Proportional Band Limit Value Xp/UL ph Pulse Period t ON t OFF Time Sample Analyzer Accessories IQ Preparation SENSOR NET Lower limit Similarly, wen te setpoint is programmed as lower limit Xp/LL, te proportional control band will start below tis value. Wen te measured value falls below te preset band, te controller will operate at maximum duty cycle factor or igest frequency respectively. Monitoring/ Liquid Control Samplers Station Proportional Control (PF) Controller Output Signal % Proportional Control (PW) Controller Output Signal % Customer Service Max. Pulse Frequency Pulse Period T 50% Pulse Frequency Proportional Band Zeit No Output Signal ph Limit Value Xp/LL t ON Proportional Band ph Limit Value Xp/LL t OFF Time 215

5 ph SensoLyt ph/orp Sensor Systems Features Long-term stability and extended sensor life Industrial-grade combination electrodes wit polymer electrolyte Low failure liability ph sensor ousing wit integral preamplifier and temperature probe Low impedance signal transmission for ig interference immunity Sensor ceck function to detect glass breakage Mecanically rugged construction Ease of maintenance due to field-replaceable electrode SensoLyt System Design For continuous ph/orp measurement, especially under te difficult conditions very often found in sewage treatment facilities, very ig demands are made concerning te reliabilty and operating safety of te systems employed. For more tan tree decades, WTW`s field-proven ph/orp measuring systems can satisfy tese requirements to te fullest. Designed specifically for tese ars applications, te SensoLyt sensors are precision engineered assemblies, wic consist of a submersible ousing wit a built-in preamplifier and te appropriate combination ph or ORP electrode. In combination wit our ig-performance monitors, te sensors constitute an integrated, extremely reliable ph/orp measuring system wic represents te igest standard, state-of-te-art tecnology wit regard to accuracy, EMC noise immunity and economy. 216

6 SensoLyt Combination Electrodes Te reliability of ph and ORP measurements are determined to a large extent by te quality of te ph/orp electrode wic commonly is exposed to extreme conditions; particularly in many industrial applications. Wit its special design, WTW Sensolyt combination electrodes are superior to conventional electrodes in terms of failures and durability. Te design of te applied reference system used is crucial to te overall performance of an electode. In Sensolyt combination electrodes te reference is a conventional Ag/AgCl/Cl electrode system, completely embedded in a pressure resistant solid gel-polymer Process Fluid electrolyte. As concentration canges in gel-type electrolyte occur very slowly, i.e. te electrocemical caracteristic of te cell is uncanged, a stable and constant reference potential will be acieved. SensoLyt SEA / SE* Tis pressure and temperature resistant combination ph electrode incorporates a double pin-ole diapragm and a gel polymer solid electrolyte, wic is AgCl free and terefore resistant to sulfides. Tis ph electrode is specially designed for use in moderately to igly polluted municipal and industrial wastewater. Measuring range: ph Higly contaminated sewage Emulsions and suspensions Media containing proteins and sulfides SensoLyt GDA / GD* Te GDA version, employing a modified gel electrolyte and a ceramic diapragm, is a low cost electrode for ph measurements. It is termally stable and most often used in ligtly polluted process media. Measuring range: ph Low-rate wastewater Surface waters Drinking water treatment Process fluids containing proteins ph/orp Sensors Wit tis electrode design, te polymer matrix/process fluid interpase consists of a pinole diapragm; i.e. an electrical flux is establised troug two fine oles in te cell of te reference system. Suc a diapragm especially reduces te risk of failures. In addition, Sensolyt combination electrodes require very little maintenance as tere is no electrolyte replacement. Glass Glass Pinole Diapragm SensoLyt Gel-polymer Electrolyte NEW SensoLyt ECA / EC* Tis combination ph electrode as a single pin-ole diapragm and a gel electrolyte. Wit its long-term stability it provides an economical solution, particularly in te communal wastewater sector. Measuring range: ph normally polluted wastewater SensoLyt PtA / Pt* Similar to te Sensolyt SEA regarding its design features and electrocemical caracteristics, te Sensolyt PtA is an combination ORP electrode. It is also fitted wit a pinole diapragm, and is primarily recommended for applications in eavily contaminated wastewater. Measuring range: ± 1000 mv Municipal and industrial sewage Emulsions and suspensions Media containing proteins and sulfides General Features Oxygen (D.O.) ph/orp On-line Instrumentation Conductivity Temperature IQ SENSOR NET Accessories Analyzer Sample Preparation Liquid Samplers Monitoring/ Control Station Customer Service SensoLyt SEA SensoLyt ECA * electrode witout armor for direct use in flow-tru vessels 217

7 ph SensoLyt Sensor Assemblies 311 Ø 40 Protective Sleeve POM Sensor Body POM Electrode Guard PVC Twist-lock Cap for Electrode Connection Temperature Sensor 316 SS SensoLyt ph electrode SensoLyt sensor assemblies perform multiple functions in te WTW concept: preamplification of te electrode signal older for an integrated NTC sensor for temperature measurement reliable protection of te installed ph-electrodes against mecanical damage Te very low voltage signal delivered by te ph/orp electrode is very susceptible to noise and ground-loop interferences. For tis reason WTW as integrated a preamplifer in te sensor assemblies. Its amplification and impedance conversion assure low-impendance and tus reliable signal transmission over long distances; e.g. required for operation wit remotely installed monitors. In addition, electrical isolation of te preamplifier prevents influences from external field potentials. SensoLyt sensor assemblies feature a built-in NTC termistor for temperature measurement and automatic temperature compensation. Tis enables bot ph or ORP and temperature to be measured simultaneously wit a single probe. Under te rigorous operating conditions of an industrial plant, e.g. a wastewater treatment plant, te rugged design of te ousing provides important mecanical protection of te glass ph electrode. For service purposes, te electrode can be replaced in te field witout tools; O-ring seals are supplied wit te electrodes. SensoLyt 700 Te SensoLyt 700 standard assembly incorporates an integrated preamplifier and a built-in stainless steel NTC sensor. Wen using a WTW monitor, a special circuitry allows te ph electrode to be monitored for glass breakage. In addition, te SensoLyt 700 offers as a standard feature an efficient ligtning protection system. Te SensoLyt 700 sensor assembly can be fitted wit any combination electrode of te SensoLyt series. It is compatible wit all WTW monitors of te TecnoLine, EcoLine and QuadroLine Series. SensoLyt 690 Te SensoLyt 690, a cost-effective unit, features te same mecanical design and almost identical tecnical specifications as te SensoLyt 700 standard model, but witout te SensCeck function. SensoLyt 650 Te SensoLyt 650 unit is a passive assembly witout preamplifier; i.e., it is designed for ig-impedance operation wit te electrode connected directly to te monitor input. Te assembly includes an integrated NTC sensor, its mecanical construction is te same as tat of te standard Model 700. Te assembly is directly compatible wit te ig-impedance input of following WTW monitors: ph 170 models, ph 296 models and ph Ex. 218

8 ph/orp Sensors Tecnical Data SensoLyt Sensor Assemblies Integrated Preamplifier Yes Yes No Signal Output Low impedance Low impedance Hig impedance Sensor Ceck Function Yes No No Temperature Measurement Integrated NTC termistor, C Ambient Conditions Operating temperature: C Electrical Connection Integral PU connecting cable wit fitted 7-pole Integral PU connecting cable, screw connector; protection rating IP 65wit bare cable ends Integrated Ligtning Built-in ligtning protection circuits (inputs and outputs): Protection Coarse protection: 90 V / 5 ka (8/20 msec); fine protection: 600 VA max. EMI/RFI Conformance According to EN class B, Annex A, FCC class A (enanced specifications) Certifications CE, TÜV/GS, CUL, UL Mecanical Sensor body: POM; Protective cap: PVC Protection rating: IP 68 Dimensions 311 x 40 mm, L x D Weigt 1 kg, approx. Temperaturductivity (D.O.) Features Instrumen- Con- ph/orp Oxygen General On-line tation Tecnical Data SensoLyt Combination Electrodes SEA / SE* GDA / GD* ECA / EC* PtA / Pt* Electrode Type Gel-polymer Modified gel electrolyte Gel-Elektrolyt Gel-polymer solid electrolyte ceramic diapragm single pinole diapragm solid electrolyte double pinole diapragm pinole diapragm Measuring Range ph ph ph ± 1000 mv Ambient Conditions Operating temperature: C Mecanical Cylindrical glass membrane, PVC armouring, and 2 Viton O-ring seals for mounting into SensoLyt sensor assemblies Dimensions Lengt 120 mm (witout plug ead) Electrical Connection Watertigt plug ead connector * electrode witout armor, e.g. for direct use in flow-tru vessels Sample Analyzer Accessories IQ Preparation SENSOR NET Ordering Information ph/orp Sensors Description Order No. ph/orp sensor wit integrated preamplifier; cable lengt 7m SensoLyt SensoLyt 700-SO ph/orp sensor wit integrated preamplifier; cable lengt to be specified SensoLyt Same as Model 700-7, witout SensCeck function SensoLyt 690-SO Same as Model 700-SO, but wit special cable lengt** V SensoLyt ph/orp sensor for ig impedance operation; cable lengt 7m SensoLyt SEA ph combination electrode, measuring range ph, for mounting into SensoLyt sensor assemblies SensoLyt GDA ph combination electrode, measuring range ph, for mounting into SensoLyt sensor assemblies SensoLyt ECA ph combination electrode, measuring range ph, for mounting into SensoLyt sensor assemblies SensoLyt PtA ORP combination electrode, measuring range ± 1000 mv, for mounting into SensoLyt sensor assemblies SensoLyt -SE Same as Model SEA, but witout armor; e.g. for direct use in flow-tru vessels SensoLyt -GD Same as Model GDA, but witout armor; e.g. for direct use in flow-tru vessels SensoLyt -EC Same as Model ECA, but witout armor; e.g. for direct use in flow-tru vessels SensoLyt -Pt Same as Model PtA, but witout armor; e.g. for direct use in flow-tru vessels For buffer solutions please refer to page 42 ** please give special cable lengt in m in your order Customer Monitoring/ Liquid Service Control Samplers Station 219

9 ph General information about EcoLine instruments can be found on pages EcoLine ph 170 ph/orp Monitor Features Ligtning protection 2 scaleable ma outputs Enanced electromagnetic conformance (EMC) Galvanically isolated inputs and outputs 2 programmable relays IP 66 enclosure RS 485 interface PROFIBUS DP gateway available Low and ig-impedance ph input Compatible wit any NTC and Pt 100/ Pt 1000 temperature sensor Automatic temperature compensation 3 calibration modes Proportional controller for dosing valves and pumps 24 VAC/VDC models available Sensor-Ceck function Built-in timer for connecting a cleaning system Protective measures In order to assure te igest possible reliabilty of WTW instruments, in view of today`s industrial requirements for process analysis, additional electronic protection measures ave been implemented. For instance, our field-proven EMC design concept in te EcoLine series ensures ig immunity to electromagnetic interference. Tis is supplemented by, among oter provisions, a consequent galvanical isolation of inputs and outputs. Proportional Control Te EcoLine ph 170 R incorporates a proportional control mode wit pulsewidt or pulse-frequency modulation wic is useful to directly regulate precipitation and neutralization processes. Sensor Compatibility Te EcoLine ph 170 provides bot low and ig impedance signal inputs. Wit tis feature te monitor will not only accept WTW SensoLyt sensors, but also te output from any oter sensor. If te adapted sensor does not include an integrated temperature probe, any treeconductor Pt 100 / Pt 1000 RDT can be connected for additional temperature measurement and automatic compensation. Calibration is accomplised by fine adjustment of te probe signal. Calibration wit Buffer Readout Calibration of te ph 170 monitor can be performed in tree different modes. AutoCal TEC 1 is an automatic, singlebutton calibration procedure using WTW tecnical buffer solutions. Wit te AutoCal TEC 2 metod, in addition, te buffer solution values can be documented via te recorder output in conjunction wit a relay trigger. In te ConCal mode, a conventional calibration wit any buffer solutions is performed entering te buffer solution values manually. 226 Year IP 66 2 Warranty

10 Tecnical Data EcoLine ph 170 EcoLine ph 170 ph Measurement ORP Measurement Temperature Measurement Measuring Ranges ph mv mv NTC: C Pt 100/Pt 1000: C Resolution 0.01 ph 1 mv 0.1 K Accuracy (± 1digit) ± 0.01 ph ± 2 mv NTC: ± 0.2 K; Pt 100/Pt 1000: ± 0.1 K fine adjustment ± 0.5 K Signal Input Low impedance or Low impedance or 2-conductor (NTC) ig impedance ig impedance 3-conductor (Pt 100/Pt 1000) Temperature Measurement NTC termistor, integrated in SensoLyt sensor assembly; or separate NTC/Pt 100/ Pt 1000 Temperature Compensation NTC: C; Pt 100/Pt 1000: C Calibration Modes AutoCal1: Automatic calibration wit tecnical buffer solutions AutoCal2: Automatic calibration wit tecnical buffer solutions and subsequent analog output of buffers used in calibration ConCal : Manual calibration wit any buffer solutions Calibration Range Slope range: -62 mv/ph S -50 mv/ph Asymmetry potential: -45 mv Uasy +45 mv Display Dual numeric LCD-readout, 3 1/2 digits for values and display of units; Grapic symbols for auxiliary information and operator guidance Relay Outputs 1 Sensor alarm relay (sensor failure); 2 programmable relays (setpoints, delay, ysteresis, control function), 1 Relays are form C rated 5A at 230 VAC, max. 30 VDC resistive Analog Outputs Two isolated 0/4-20 ma -outputs for ph/orp and temperature, 2 max. load 600 W, basic accuracy 0.1%; Output span and recorder damping adjustable by software Serial interface RS 485 interface, bus operation wit up to 31 instruments possible 3 Ambient Conditions Operating temperature: -25 C C Storage temperature: -25 C C) Climate class 4 (VDI/VDE 3540) Electrical Connections Sensor input: quick disconnect 7-pole receptacle (weaterproof) Signal inputs and outputs, mains supply: via plug-in terminal strips Input Power 115/230 VAC (-15/+10%), Hz (18 VA max.) 24 VAC (-15/+10%), 24 VDC (-30/+20%) Transient Voltage Built-in ligtning protection circuits (inputs and outputs). Protection Coarse protection: 90 V / 1.5 ka (8/20 msec); fine protection: 600 VA max. EMI/RFI Conformance According to EN class B, Annex A, FCC class A Namur recommendations (enanced specifications) Certifications CE, TÜV/GS, CUL, UL (pending) Enclosure Watertigt ousing (PC/GF20) wit treaded receptacle and four cable feed-troug connections (PG compression fittings, mm dia.); Protection rating: IP66 (exceeds NEMA 4X). Dimensions 222 x 202 x 105 mm, W x H x D Weigt 3.5 kg, approx. 1 R-version 2 T-version 3 RS-version Ordering Information EcoLine ph 170 Standard Instrument / Options ph 170 Standard: witout relay outputs 18 R Option: wit 2 programmable relays Standard: 1 analog output for ph/orp T Option: 2 analog outputs for ph/orp and temperature Standard: witout RS 485 interface RS Option: wit RS 485 interface 230 Standard: 230 V, 50/60 Hz 115 Option: 115 V, 50/60 Hz 24AC 24 VAC, 50/60 Hz 24 VDC 24DC 1 2 Order No Customer Monitoring/ Liquid Sample Analyzer Accessories IQ Temperaturductivity (D.O.) Features Instrumen- Con- ph/orp Oxygen General On-line Service Control Samplers Preparation SENSOR NET Station tation ph 170 Please coose one from eac category and complete te order number accordingly 18 R T 115 ph 170 Example: EcoLine ph 170 wit 2 programmable relays, analog outputs for ph/orp and temperature, 115 V version 227