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Combitec Konzentrationsmessung

COMBITEC - Concentration Analysis

COMBITEC - Concentration measurement (3-component mixture)

COMBITEC combines the functionality of RHOTEC (density measurement) and SONATEC (speed of sound measurement). The instrument is designed for applications requiring maximum sensitivity and the highest accuracy. It is easy to use and maintenance-free. For density measurement, the liquid flows through a thin, U-shaped tube inside the sensor. Electromagnets excite the tube to vibrate at its resonant frequency. Simultaneously, an internal reference oscillator measures the vibration behavior. Even the smallest changes in the liquid's density affect the measured signal and are detected with the highest precision. For speed of sound measurement, a sound pulse is generated by a piezoelectric element in an ultrasonic transmitter. It travels perpendicular to the product flow toward an ultrasonic receiver, where it is detected. Since the distance between the transmitter and receiver is known, the speed of sound can be easily determined by measuring the time it takes the sound signal to travel. As a specific property of each liquid, the relationship between concentration and density, or speed of sound, can be described by a mathematical polynomial. With decades of experience and our own laboratory facilities, Centec knows the polynomials for a large number of products. Temperature drifts of the measurement signal are automatically compensated by an internal Pt1000 sensor. COMBITEC can display liquid density, speed of sound, and solution concentration in a wide variety of units.

European patent application: 1 439 438 B1

  • Most accurate technology for determining density, speed of sound and concentration
  • Patented compact design with local display available
  • Large number of materials and flange connections
  • Hygienic design and full CIP capability
  • Easy to use and maintenance-free
  • Application:

    COMBITEC is used for 3-component systems to simultaneously measure densities, sound velocities and concentrations, e.g., in a mixture of acid and salt in water or in systems such as sulfuric acid/oleum and methanol/formaldehyde.

  • Technical data:

    Technical data

    Measurement range: density & speed of sound 0 -3 g/cm3 and 400 - 3,000 m/s
    Accuracy, density & speed of sound ± 0.0001 g/cm3 and ± 0.05 m/s
    Reproducibility, density & speed of sound ± 0.0001 g/cm3 and ± 0.01 m/s
    response time ≤ 1 s
    Operating pressure max. 16 bar
    Operating temperature -25 to +125 °C
    temperature sensor Pt1000
    material 1.4404/1.4435/AISI 316L; Hastelloy; Tantalum; others on request
    Connections Compatible with Varivent© inline housings DN40 - DN150; others available on request
    Input Transmitter Version 10 x digital (24 VDC) & 2 x analog (4 - 20 mA)
    Output Transmitter Version 5 x digital (24 VDC) & 4 x analog (4 - 20 mA)
    Profibus DP transmitter version option
    Profibus DP sensor (without local display) standard
    Protection class IP65
    power supply 24 VDC

Processes that inspire. Technology that thinks ahead.

Learn more about our systems and services. Contact us for tailored proposals and expert guidance.

Wilhelm-Roentgen-Straße 10, D-63477 Maintal

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