TY - JOUR
T1 - Performance of conventional starches as natural coagulants for turbidity removal
AU - Choy, Sook Yan
AU - Prasad, Krishnamurthy Nagendra
AU - Wu, Ta Yeong
AU - Raghunandan, Mavinakere Eshwaraiah
AU - Ramanan, Ramakrishnan Nagasundara
N1 - Funding Information:
The authors are grateful to Monash University Malaysia for providing the research scholarship and essential support for this work Choy Sook Yan is a recipient of the Higher Degree by Research Scholarship (HDR) awarded by Monash University Malaysia. Special thanks also to Holy Mate Sdn. Bhd. for providing the PACl stock liquid used in this study.
Publisher Copyright:
© 2016 Elsevier B.V.
PY - 2016/9
Y1 - 2016/9
N2 - The efficiency of rice, wheat, corn and potato starches in removing turbidity was performed and compared to alum and polyaluminium chloride. Using kaolin suspensions, the effects of pH, dosage and need for starch gelatinization was studied. Autoclaved rice starch with larger polymer chain length outperformed other starches to yield 50% turbidity removal with an optimized dosage of 120 mg/L and initial pH of 4 at a sedimentation time of 30 min. The integrated use of autoclaved rice starch and chemical coagulants as a two step coagulation process has further increased the efficiency of turbidity removal by at least 30%. This process has also reduced the amount of chemical-based sludge by 60% which was highly favourable. SEM images of starch treated flocs revealed distinct bridging of kaolin particles in-line with properties of respective coagulation mechanisms specifically adsorption and bridging. This study further conduces to the understanding of starches as coagulants and puts forward a basis for the characterization of resulting flocs.
AB - The efficiency of rice, wheat, corn and potato starches in removing turbidity was performed and compared to alum and polyaluminium chloride. Using kaolin suspensions, the effects of pH, dosage and need for starch gelatinization was studied. Autoclaved rice starch with larger polymer chain length outperformed other starches to yield 50% turbidity removal with an optimized dosage of 120 mg/L and initial pH of 4 at a sedimentation time of 30 min. The integrated use of autoclaved rice starch and chemical coagulants as a two step coagulation process has further increased the efficiency of turbidity removal by at least 30%. This process has also reduced the amount of chemical-based sludge by 60% which was highly favourable. SEM images of starch treated flocs revealed distinct bridging of kaolin particles in-line with properties of respective coagulation mechanisms specifically adsorption and bridging. This study further conduces to the understanding of starches as coagulants and puts forward a basis for the characterization of resulting flocs.
KW - Alum
KW - Coagulation-flocculation
KW - Floc characteristics
KW - Natural coagulant
KW - PACl
KW - Starch
UR - http://www.scopus.com/inward/record.url?scp=84975267509&partnerID=8YFLogxK
U2 - 10.1016/j.ecoleng.2016.05.082
DO - 10.1016/j.ecoleng.2016.05.082
M3 - Article
AN - SCOPUS:84975267509
SN - 0925-8574
VL - 94
SP - 352
EP - 364
JO - Ecological Engineering
JF - Ecological Engineering
ER -