Assessment of the capability of an optical sensor for in-line real-time wastewater quality analysis in food manufacturing

This work investigates the use of a commercial optical product monitor to achieve in-line real-time water content analysis. Test fluids were used and optical measurements of attenuation of light intensity at four colours were made. These measurements were used to identify any relationship between these and the water quality parameters of turbidity and colour. Variation in light attenuation for turbidities up to 1700 NTU was successfully resolved by the instrument, with optical data for turbidities ≥ 20 NTU fitting well the Beer-Lambert model. The sensor was also able to clearly identify the effect of filtering out suspended solids with unfiltered samples (apparent colour) exhibiting significantly higher attenuation coefficients than filtered samples (true colour). Further studies will concentrate on whether the instrument can analyse samples with turbidities higher than 1700 NTU, together with further investigating the variation in the attenuation coefficient seen with turbidity and colour of light.