Optimising algae floc structure for more efficient separation

FTIR-1
FTIR imaging of Chlorella vulgaris fixed with 4% PFA scanned using 16 cm-1 resolution and FTIR reflectance mode showing a) lipids centred at 2900 cm-1, (b) proteins centred at 1610 cm-1 and (c) carbohydrates centred at 1125 cm-1

Project description

The presence of algal or cyanobacterial blooms in drinking water sources represents a challenge to water utilities as it creates operational problems including increasing coagulant demand and cell carry-over to downstream processes. A key barrier to cyanobacteria and algae in the water treatment plant is the separation processes, such as sedimentation and dissolved air flotation (DAF), preceded by coagulation and flocculation (C-F). However, coagulation of biological systems, such as algae, is complex and further research is required to improve understanding of the coagulation/flocculation process such that floc properties can be suitably tailored for downstream separation. The aim of this project is to develop a novel method to examine the chemical character of the floc to give additional fundamental understanding on floc composition and to lend insight into physical floc properties. Optimal floc properties will then be linked to separation processes including sedimentation and dissolved air flotation. The research will also be applied to separation systems used in an algae harvesting context for energy production.   

 

Publications

Gonzalez-Torres, A., Putnam, J., Jefferson, B., Stuetz, R.M. and Henderson, R.K. (2014) Examination of the physical properties of Microcystis aeruginosa flocs produced on coagulation with metal salts. Water Research 60, 197-209.

Ometto, F., Pozza, C., Whitton, R., Smyth, B., Gonzalez-Torres, A.G., Henderson, R.K., Jarvis, P., Jefferson, B. and Villa, R. (2014) The impacts of replacing air bubbles with microspheres for the clarification of algae from low cell-density culture. Water Research 53, 168-169.