Coagulation applications for new treatment goals

Abstract

The objectives for coagulation-based processes have changed significantly as a consequence of new goals for lower treated-water turbidity and criteria for total organic carbon (TOC) removal to meet requirements for enhanced coagulation. Although the application of coagulation for TOC removal has garnered considerable interest, the capability to maintain effective turbidity removal is a higher priority and cannot be compromised. This article describes evaluations for assessing this broader view of the coagulation process and underlines the necessity of identifying coagulant adjustments that not only remove TOC but also achieve effective particulate removal. Several basic coagulation adjustments are available for improving capability to meet goals for TOC and turbidity removal, including changes in pH and coagulant dose, use of alternative coagulant chemicals, and changes in the order of chemical addition.

Treatability of U.S. Environmental Protection Agency Contaminant Candidate List Viruses: Removal of Coxsackievirus and Echovirus using Enhanced Coagulation

“…14 Doses are heavily dependent on water quality, and are therefore widely variable. 15 Enhanced coagulation doses range from 5 to 150 mg/L FeCl3, 14 but more commonly range from 20 to 60 mg/L FeCl3. 4 In this study, coagulant doses ranging from 20 to 120 mg/L FeCl3 were tested in increments of 20 mg/L in an effort to optimize coagulant dose.…”

Efficacy of Removal of CCL Viruses under Enhanced Coagulation Conditions

“…Variations in water quality parameters have been reported to significantly impact the performance of coagulation, sedimentation, and filtration. 17,20 accessed by following the link in the citation at the bottom of the page.…”

“…Ferric chloride doses are heavily dependent on water quality and are therefore widely variable. 20 Enhanced coagulation doses range from 5 to 150 mg/L FeCl3, 7 but are commonly in the range of 20−60 mg/L FeCl3. 5 Coagulant doses ranging from 0 to 120 mg/L FeCl3 were tested in increments of 20 mg/L in this study.…”

Pharmaceutical removal from water with iron- or manganese-based technologies: A review

“…Ferric salts, including FeCl 3 and Fe 2 (SO 4 ) 3 , are commonly used in flocculation and coagulation processes for organic matter removal from drinking water and wastewater (Budd et al, 2004;Matilainen et al, 2010;Liu et al, 2013). Excess Fe(III) is generated by zero-valent iron/H 2 O 2 system and improves flocculation and coagulation of organic pollutants (Neyens and Baeyens, 2003;Kallel et al, 2009).…”