Using submersible fluorescence sensors to track the removal of organic matter in decentralized wastewater treatment systems (DEWATS) in real time

Abstract

Decentralized wastewater treatment systems (DEWATS) using anaerobic treatment are increasingly being considered for wastewater treatment with options for non-potable water reuse at the community scale. One challenge for ensuring performance and reliability of DEWATS is the lack of suitable on-site sensors to monitor failure or contamination events. In this study, the aim was to use

In situ fluorescence measurements of dissolved organic matter: A review

“…Also, Wasswa et al (2019) mentioned that in complex environments, the instruments may not measure towards the minimum LOD due to background fluorescence. Although field fluorimeters have lower sensitivity and LOD ranges compared to benchtop spectrofluorimeters, they are still able to detect the same patterns and trends as laboratory instruments (Mladenov et al, 2018).…”

“…In particular studies, no corrections were applied, due to low concentration of dissolved or suspended matter and narrow temperature ranges in the monitored water. For example, Carstea et al (2018), Mladenov et al (2018) and Singh et al (2015) used uncorrected data to monitor fluctuations in the fluorescence intensity of wastewater and recycled water. Since in situ fluorimeters were able to detect minor changes in effluent DOM without any data correction, Carstea et al (2018) recommended using them without any corrections only for qualitative data, preliminary testing and early warning of underperformance issues.…”

“…Although few studies were conducted, the results were promising in determining the effectiveness of treatment processes. Studies on field fluorescence assessment of engineered water systems included drinking water treatment plants (Shutova et al, 2016), wastewater treatment plants (Carstea et al, 2018;Mladenov et al, 2018) and recycled water plants (Singh et al, 2015) (Table S5). Shutova et al (2016) identified daily changes in DOM at the untreated water and a stable DOM at the treated water.…”

“…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.…”

“…Moreover, the research in this field has increased, in the past five years, with several in situ measurement studies on the quality of groundwater (for example, Li et al, 2016a;Sorensen et al, 2018a), freshwater (Khamis et al, 2015;Snyder et al, 2018), marine water (Chen et al, 2015;Cyr et al, 2017) and engineered water systems (Carstea et al, 2018;Mladenov et al, 2018;Shutova et al, 2016;Singh et al, 2015). This paper aims to review the advances in water quality measurements using in situ fluorescence devices for detection of fluorescence emitted by DOM in the ultraviolet (UVA -320 -400 nm) and blue light regions (430nm), and their characterization, in marine, freshwater, groundwater and engineered water systems.…”