Coagulation and disinfection by-products formation potential of extracellular and intracellular matter of algae and cyanobacteria

Ziming Zhao; Wenjun Sun; Ajay K Ray; Ted Mao; Madhumita B Ray

doi:10.1016/j.chemosphere.2019.125669

Coagulation and disinfection by-products formation potential of extracellular and intracellular matter of algae and cyanobacteria

Chemosphere. 2020 Apr:245:125669. doi: 10.1016/j.chemosphere.2019.125669. Epub 2019 Dec 17.

Authors

Ziming Zhao¹, Wenjun Sun², Ajay K Ray¹, Ted Mao³, Madhumita B Ray⁴

Affiliations

¹ Department of Chemical and Biochemical Engineering, Western University, London, Ontario, N6A 5B9, Canada.
² School of Environment, Tsinghua University, Beijing, 100084, China; Research Institute for Environmental Innovation (Suzhou), Tsinghua University, Jiangsu, 215163, China.
³ Trojan Technologies, London, Ontario, N5V 4T7, Canada.
⁴ Department of Chemical and Biochemical Engineering, Western University, London, Ontario, N6A 5B9, Canada. Electronic address: mray@eng.uwo.ca.

PMID: 31881385
DOI: 10.1016/j.chemosphere.2019.125669

Abstract

Coagulation and flocculation can remove particulate algal cells effectively; however, they are not very effective for removing dissolved algal organic matter (AOM) in drinking water plants. In this work, optimum coagulation conditions using alum for both extracellular and intracellular organic matter of six different algal and cyanobacterial species were determined. Different coagulation conditions such as alum dosage, pH, and initial dissolved organic carbon (DOC) were tested. Hydrophobicity, hydrophilicty, and transphilicity of the cellular materials were determined using resin fractionation method. The removal of DOC by coagulation correlated well with the hydrophobicity of the AOM. The disinfection by-product formation potential (DBPFP) of various fractions of AOM was determined after coagulation. Although, higher removal occurred for hydrophobic AOM during coagulation, specific DBPFP, which varied from 10 to 147 μg/mg-C was higher for hydrophobic AOM. Of all the six species, highest DBPFP occurred for Phaeodactylum tricornutum, an abundant marine diatom species, but is increasingly found in surface water.

Keywords: Algal organic matter; Coagulation; Disinfection by-product formation potential; Hydrophobicity; Resin fractionation.

MeSH terms

Alum Compounds*
Cyanobacteria / chemistry*
Diatoms / chemistry
Disinfection*
Flocculation*
Hydrophobic and Hydrophilic Interactions
Solubility
Stramenopiles / chemistry*
Water Pollutants, Chemical / analysis*
Water Pollutants, Chemical / chemistry
Water Purification

Substances

Alum Compounds
Water Pollutants, Chemical
aluminum sulfate