Abstract
Although near infrared (NIR) spectroscopy has been evaluated for numerous applications, the number of actual on-line or even on-site industrial applications seems to be very limited. In the present paper, the attempts to produce online predictions of the chemical oxygen demand (COD) in wastewater from a pulp and paper mill using NIR spectroscopy are described. The task was perceived as very challenging, but with a root mean square error of prediction of 149 mg/l, roughly corresponding to 1/10 of the studied concentration interval, this attempt was deemed as successful. This result was obtained by using partial least squares model regression, interpolated reference values for calibration purposes, and by evenly distributing the calibration data in the concentration space. This work may also represent the first industrial application of online COD measurements in wastewater using NIR spectroscopy.
Highlights
Wastewater flows are characterized by constantly changing flow rates and composition [1]
One potential method of gaining on-line information of the organic load is to use near infrared (NIR) spectroscopy combined with quantitative models based on multivariate methods
In order to carry out the investigation with a minimal intrusion on the daily activities in the facility, it was decided that any quantitative calibration will have to rely on reference data obtained from the measurements routineously carried out by the plant operators
Summary
Wastewater flows are characterized by constantly changing flow rates and composition [1]. How to cite this paper: Dahlbacka, J., et al (2014) On-Line Measurement of the Chemical Oxygen Demand in Wastewater in a Pulp and Paper Mill Using Near Infrared Spectroscopy. The studies found represent quite diverse applications, for instance, quantitative measurements of oil, urea and solids [5], glycerol [6], and methanol and glycerol simultaneously [7] in wastewater from a biodiesel fuel production plant. As another example, in one of the few in-situ applications found [8], principal component analysis (PCA) was used instead of quantitative modelling to monitor an activated sludge plant
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
