Teledyne 6750 operating instructions TOC analysis in a continuous, on-line TOC analyzer

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Theory of Operation	Model 6750

TOC analysis in a continuous, on-line TOC analyzer.

The CO2 generated by the oxidation of carbon in the reactor is read by the NDIR as a percentage concentration of the CO2 in the carrier gas.

CO2 (TOC)

CO2 (TOC) + Carrier

Any increase or decrease of the carrier flow rate will have a corresponding inverse effect on TOC reported value, (eg. double the carrier flow rate, reported TOC will approximate ½ of actual sample TOC concentration).

The Model 6750 uses a computer-controlled mass flow controller rather than a less accurate system consisting of pressure regulation with a flow meter in a capillary system.

The inorganic carbon removal system (sparger) flow rate is controlled by needle valves (V1 & V2) set at the factory. The operator will note bubbles through the liquids in the sparger, which is stripping the CO2 converted from the carbonates to eliminate the potential interference from inorganic carbon in TOC analysis.

The carrier gas directs the CO2 and other products of oxidation from the reactor to the Gas/Liquid Separator (GLS), where liquid waste is directed to drain and gases containing CO2 and other gaseous products of oxidation are directed to the CO2 specific NDIR. The CO2 concentration is directly related to sample TOC concentration and is reported accordingly.

2.4.2Inorganic Carbon Removal/Analysis

The choice of either TOC –Direct (NPOC) or TOC-True analysis involves a method of either measuring the TIC (for a TOC-True analysis) or not (for a Non-Purgeable TOC analysis only). The Model 6750 Analyzer can perform either method. The TOC-True method measures the inorganic carbon and is able to detect volatile organic loss in the sparger. The NPOC analysis ignores the volatile organics for a less precise NPOC analysis if organic volatiles are present.

The sparger used in the Model 6750 is a gas/liquid counter-flow stripper. Actual acid addition depends on the amount of sample buffering and pH. Factory set-up is for a nominal sample pH of 7.0, to

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Contents Model Teledyne Analytical InstrumentsModel Copyright 2005 Teledyne Instruments/ Analytical InstrumentsSpecific Model Information Total Organic Carbon AnalyzerSafety Messages Total Organic Carbon Analyzer Table of Contents Setup and Operation MaintenanceAppendix Index Teledyne Analytical InstrumentsList of Figures Model 6750 TOC Analyzer Front door removedDC Power Supply Module List of Tables Combustible GAS Usage Total Organic Carbon Analyzer Introduction Main Features of the AnalyzerIntroduction Intended Use of the Analyzer OptionsTypical Applications Introduction ModelOperator Interface Model 6750 TOC Analyzer Front door removedIntroduction Model Teledyne Analytical Instruments Background Theory of OperationOverview Total Organic Carbon Analyzer Theory of OperationTheory of Operation Model Npoc or TOC Direct MethodConclusion TOC Measurement Basics UV/Heated Persulfate Method of Analysis Comparison of TOC Measurement Technologies Subsystems Principles of Operation Sample HandlingSample Handling for TOC -Direct Sample Handling TOC-True TOC analysis in a continuous, on-line TOC analyzer Inorganic Carbon Removal/AnalysisRelationship Between TIC and pH OxidationOxidation Reactions Ndir CO2 Gas Detection 10 Model 6750 Ndir UnitElectronic Signal Processing, Display and Control BENCHMARK/AUTO-VALIDATION Theory of Operation Model Teledyne Analytical Instruments Unpacking the Analyzer InstallationTotal Organic Carbon Analyzer Installation Mounting the AnalyzerInstallation Model Analyzer DimensionsPower Connection Electrical ConnectionsAnalog Outputs Electrical Connections to the Model4 RS-232 Serial Connection Alarm ConnectionsGas/liquid Connections Liquid ConnectionsGas and Liquid Connections to the Analyzer Gas ConnectionsChecking the System Gas Carrier ConnectionsInstallation Model Teledyne Analytical Instruments Analyzer Startup Setup and OperationTotal Organic Carbon Analyzer Setup and Operation Setup and Operation Model Drain ConnectionsRun Mode MenusParameter Menu Alarm Settings Stream Sequencer 5 D/DBPR Detailed Calibration Procedures Methanol 100 mg/Liter 1000 mg/LiterEthylene Glycol EthanolPreparation of Phosphoric Acid Solution Total Organic Carbon Analyzer Setup and Operation Operation RUN ScreenShutdown Historical DataSetup and Operation Model Total Organic Carbon Analyzer Maintenance MaintenanceCompupter-aided Testing Troubleshooting Maintenance ModelModule Service Ndir Gas CalibrationIR Calibration Installing Calibration Adapter Ndir ServiceRemoving the Ndir Unit P/N ST36000 Total Organic Carbon Analyzer Maintenance Maintenance Model To Reassemble Use alternate tightening sequence Master Interface Board P/N ST13042-1 Removing the Master Interface Board4 D. C. Power Supply DC Power Supply ModuleCE Computer P/N Replacing CE ComputerUV Lamp Replacement UV Lamp P/N ST20009UV Reactor Assembly P/N ST20003-1 Removing the UV Reactor AssemblyUV Power Supply 10 Removing the UV Power Supply Mass Flow Controller P/N ST18001A11 Mass Flow Controller Metering Valve P/N ST1605012 Metering Valve Sparger P/N ST2002513 Sparger Pumps Maintenance Model 14 Removing the Pump Maintenance Model 13 4-20 mA Adjustment Procedure System DiagnosticsSetting 100 MV Control Voltage Total Organic Carbon Analyzer Appendix 1SpecificationsAppendix Appendix Model Sample requirementsParts Listing Description ImageAppendix Model Total Organic Carbon Analyzer Appendix Appendix Model Total Organic Carbon Analyzer Appendix Option Auto CALTrue Dual Range Option not an electronic scaling Dbpr OptionAppendix Model AS-BUILT Drawings Appendix Model Teledyne Analytical Instruments Index Total Organic Carbon Analyzer IndexIndex Model ModbusPump mounting screw Index Model