Online monitoring of transparent exopolymer particles (TEP) by a novel membrane-based spectrophotometric method

• Main Authors: Sim, Lee Nuang, Suwarno, Stanislaus Raditya, Lee, Darren Yong Shern, Cornelissen, Emile R., Fane, Anthony Gordon, Chong, Tzyy Haur
• Other Authors: School of Civil and Environmental Engineering
• Format: Article
• Language: English
• Published: 2021
• Subjects: Engineering::Environmental engineering; Transparent Exopolymer Particles; Alcian Blue
• Online Access: https://hdl.handle.net/10356/150710
• Institution: Nanyang Technological University

The presence of transparent exopolymer particles (TEP) in water bodies has been related to several adverse impacts in various water treatment processes. In recent years, there have been an increasing number of publications relating to TEP. Unfortunately, this increased interest in TEP measurement has not been accompanied by significant improvement in the analysis method or TEP monitoring. Currently, the most common method to analyze and quantify TEP only allows offline, and often offsite measurement, causing delays and slow response times. This paper introduces an improved method for TEP monitoring using a membrane-based spectrophotometric technique to quantify TEP in various water bodies. The proposed TEP monitor involves a crossflow filtration unit, reagent injection and a spectrophotometer system. The TEP retained on the membrane surface is stained by Alcian blue and the amount deposited is quantified directly using an optic fibre reflectance probe coupled with a spectrophotometer. The novel method shows a linear relationship with various concentrations of Xanthan gum (a model representing TEP). When tested with various water samples, the proposed method was found to correlate well with the conventional method. Several advantages of this novel method are shorter analysis time, increased accuracy, and the potential to be further developed into an online system.