Page 76 - Application Handbook - TOC
P. 76

SCA-130-603



            This can take place when measurement                The software enables planning  of various
            values are exceeded or can be applied               automatic maintenance and calibration tasks.
            permanently. In this case, the user specifies       This way, automatic calibration of the
            the desired dilution factor in the selected         measuring method was programmed to take
            method.                                             place every 48 hours and automatic
                                                                regeneration of the catalyst twice a week.
            ■ Kit for high-salt samples                         Sampling took place in the counterflow mode
            For the continuous TOC determination of             with backflushing in order to prevent clogging.
            samples with high salt loads (> 10 g/L),
            Shimadzu has developed a salt kit. The              ■ Results of the practice test
            combustion tube has  a special shape and            As described in the  test, a  sample was
            uses two  different catalyst beads. This            collected every 4 minutes over a  period of
            combination prevents crystallization that can       three months, and subsequently diluted,
            lead to clogging of the system.                     acidified and analyzed. After three months a
                                                                total of approximately 27,000 measurements
            ■ TOC-4200 in daily practice                        was achieved. . Within this period, the
            To verify the robustness and the reliability of     instrument  was automatically calibrated 45
            the TOC-4200 during practical operation, the        times and the catalyst was regenerated
            analyzer has been subjected to an endurance         nearly 25 times. These functions can be
            test in a German chemical park. For three           easily programmed  via a calendar on the
            months, the TOC-4200 had to stand the test          touch screen. The calibration function
            under the most difficult conditions at one          gradients remained stable over the entire
            measuring station. The wastewater under             time period.
            investigation was alkaline (pH  ≥ 12)  and
            highly saline (conductivity 4 ≥ mS/cm).




                                                                Fig. Diagram  of 27.000 Measurement results (three
                                                                months)
                                                                The test did not require any catalyst
                                                                exchange or a single maintenance operation.
                                                                There was also no instrument or software
                                                                failure or any other component failure. In
                                                                short: the TOC-4200 has successfully passed
                                                                the endurance test.

                          Fig. TOC-4200 on site                 ■ Recommended analyzer / Configuration
                                                                TOC-4200
            This is why the instrument was equipped with        Kit for high-salt samples
            a kit for salt-containing samples. In addition,
            the automatic dilution function was used to
            dilute the  samples (including the matrix).
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