Continuous measurement of kappa number - Making a case for accurate chemical demand measurement and control

The intelligent PBS(TM) sensor rises a precision system of distributed optics to accurately measure the lignin content of pulp. By simultaneously measuring transmitted and reflected light at four distinct wavelengths; a true relative reflectance signal is generated. The signal is drift-free and contains valuable information about pulp properties. The raw measurement signals are processed and transmitted as a kappa or K number. Because the signal is continuous, PBS can be used to provide reliable measurements for closed loop control of kappa factor. Lignin readings are also tracked as a kappa number as needed for bleach plant control and monitoring. The accumulation of scale on in-line sensor probes has long been a difficult challenge. As scale builds on conventional probes, the signal drifts and loses accuracy. Historically, thee probes have been a high-maintenance item and confidence in the accuracy of the signal has been low. With PBS, this problem ran be virtually eliminated with the ultrasonic cleaning option. Calibration to PAPTAC, TAPPI, APPITA and SCAN standards are all possible, using the integrated Windows(TM)-based software tools.