RSC Water Forum: Flow Cytometry Day Using Flow Cytometry as a Process Diagnostic Tool In Drinking Water Treatment RSC Water Forum: Flow Cytometry Day
Using Flow Cytometry as a Process Diagnostic Tool In Drinking Water Treatment
Claire Thom
1. Background to Scottish Water 2. Our Flow Cytometry Journey
3. Initial Work 4. Expanding the Project
5. Using Big Data 6. Online FCM 7. Next Steps
Outline
Upland peat moor – humic and infertile in nature, granite rock
High rainfall (western highlands one of the highest rainfall areas in Europe.
Raw Waters with seasonally high organic content, low alkalinity and typically very flashy
East: Limestone sandstone/ clays, soil, grassland – fertile
Relatively lower rainfall
Water bodies: Relatively more stable and of lower organic content
c.50% of Scotland’s WTW’s <5% of the population
Scottish Water’s Flow Cytometry Journey so Far…. Initial
Intact/Total Cell method
traditional coagulation/filt
ration treatment
Expanded by another 20
period.
Scotland
Initial Method Development: 2013
• MRes Project
• Sample stability study – effect of sample age on cell count with storage at different temperatures
• Daily monitoring of regulatory microbiology samples taken from Mannofield/Invercannie, Glendevon and Roberton supplies.
• Samples taken from the residual volume left after routine microbiology testing – only around 2ml required.
Risk reduced through optimisation
Expanding the Project: 2015-17
• Assessing 4 aspects of works performance:
» Coagulation/Clarification
» Filtration
» Disinfection
» System legs- network regrowth
• Production of a site specific report on WTW and Network bacto performance, with recommendations for improvements.
• On site- analysis for c.1 week to 2 weeks at each site throughout 2016
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Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct
2015 2016
C e
lls /m
Old tank averages 37% higher total
cells.
• Repeat Coliform failures from WTW.
• Isolated to the old Clean Water Tank.
• Cell counts in the preceding months showed marked increases.
2018: Big Data
Next Steps…
• Apply new process control technology and learning to a pilot system.
• RT Coliform/E.coli monitoring.
• Online Flow Cytometry
• Identify any relationships between pathogen loading and Coliform failures.
• Carry out sampling across pilot plant under optimal and suboptimal conditions.
• Identify impacts of process failure.
• Apply knowledge to live systems to understand failure implications and inform QMRA processes.
Enhancing Process Control
filtration
Collaborate with SLM Team to ensure Catchment ‘character’ is assessed, quantified & linked into process performance conclusions
Investigate & create optimal Coagulation Control systems for Scottish Waters based around Zeta, S.C & UV abs / Fluorescence
Build ‘smart’ measurement tool to allow for clear measurement & performance monitoring
Build & test enhanced inter- stage Laboratory analysis suite of traditional & novel techniques to test value & quantify hazard loadings / process unit performance
Fully test & report on the impacts of returning wash-water to the headworks and value of filter slow start
Utilise FCM alongside, advanced laboratory techniques and on-line coliform analysis to measure & assess microbial loadings, their fate through the process and the significance of process control (QMRA)
Utilise R&I Filter column and CCT pilot plants to test and evidence the various enhancement scenarios inclusive of media choices, backwash operation, disinfection configurations.
Collaborate with Asset Capability Team to ensure rounded site assessment
PhD Project: Improving Measures of Pathogens and Health Risk in Drinking Water
1. Identify new potential indicators.
2. Develop new molecular analyses for identification.
3. Analyse on TEP pilot system during routine and abnormal operations.