Sludge watch shows water performance
New methods for tracking sewage sludge flows could aid the design of better wastewater treatment plants.
Researchers at RMIT University demonstrated how the flow behaviour of sludge can be used as a tool to gauge how quickly organic matter is dissolving at high temperatures, paving the way for online monitoring of process performance.
Traditional methods of assessing the performance of thermal treatment require time-consuming sampling and chemical analysis.
But rheology calculations – which measure and detail how liquids flow - can be done online in real time.
The researchers found a correlation between how sludge dissolves and changes in its flow behaviour, indicating it may be possible to monitor thermal treatment performance simply by tracking the flow.
“Our technique enables engineers and plant operators to conveniently obtain these parameters without having to perform the measurements at high temperatures themselves,” said lead investigator Associate Professor Nicky Eshtiaghi.
“We hope the research encourages more serious consideration of flow behaviour in optimising and designing high pressure and high temperature sludge-handling processes.”
The equations in the study are based on direct measurement of sludge at conditions that mimic real-world thermal treatment processes.
The new technique can measure flow behaviour without destroying the samples, often a big challenge during data collection of concentrated sludge.