Monitoring biological wastewater treatment processes: recent advances in spectroscopy applications

Abstract

Biological processes based on aerobic and anaerobic technologies have been continuously developed to wastewater treatment and are currently routinely employed to reduce the contaminants discharge levels in the environment. However, most methodologies commonly applied for monitoring key parameters are labor intensive, time-consuming and just provide a snapshot of the process. Thus, spectroscopy applications in biological processes are, nowadays, considered a rapid and effective alternative technology for real-time monitoring though still lacking implementation in full-scale plants. In this review, the application of spectroscopic techniques to aerobic and anaerobic systems is addressed focusing on UV-Vis, infrared, and fluorescence spectroscopy. Furthermore, chemometric techniques, valuable tools to extract the relevant data, are also referred. To that effect, a detailed analysis is performed for aerobic and anaerobic systems to summarize the findings that have been obtained since 2000. Future prospects for the application of spectroscopic techniques in biological wastewater treatment processes are further discussed.

In situ fluorescence measurements of dissolved organic matter: A review

“…Despite multiple indications in the literature that fluorescence sensors can be used for in situ measurements of wastewater treatment processes (Carstea et al, 2016;Chong et al, 2013;Mesquita et al, 2017), only two studies have been published so far (Carstea et al, 2018;Mladenov et al, 2018). The main reason for the slow advancement is the difficulty of using this technique in the hostile environment of a wastewater treatment plant (i.e.…”

Environmentally-friendly technology for rapid identification and quantification of emerging pollutants from wastewater using infrared spectroscopy

“…Nowadays, FTIR techniques are becoming widespread in monitoring wastewater treatment processes. Several parameters can be measured with this technique as alcohols and volatile organic acids (Nespeca et al, 2017), biogas production (Stockl and Lichti, 2018), biochemical oxygen demand, chemical oxygen demand (COD), turbidity, total organic carbon (TOC) and volatile fatty acids (VFA), among others (Mesquita et al, 2017). On the other hand, the quantification of pharmaceuticals, and other emerging pollutants, in wastewaters by FTIR and chemometrics is just starting to have the attention of the scientific community (Quintelas et al, 2019).…”

Quantification of pharmaceutical compounds in wastewater samples by near infrared spectroscopy (NIR)

“…FT-NIR techniques are also frequently used to monitor wastewater treatment processes. The parameters usually evaluated by this technique include polyhydroxyalkanoates, extracellular polymeric substances, biochemical oxygen demand, chemical oxygen demand, total suspended solids, total organic and inorganic carbon, bicarbonate alkalinity, biochemical methane potential, volatile fatty acids, nitrate, ammonia [19] and volatile organic pollutants as tetrachloroethylene and dichlorobenzene ( [20,21]) and fenitrothion [22]. However, the quantification of pharmaceuticals in wastewaters by FT-NIR is a field to explore and, to the authors' knowledge, no relevant works exist in the literature describing the use of this technique at this level.…”