Use of flocculants for wastewater treatment

Abstract

Polymeric flocculants are used to accelerate the separation of solid and liquid phases in the treatment of drinking water and wastewater. Recently, much attention has been paid to flocculants, both synthetic and biobased, due to their advantages for wastewater treatment processes. Flocculants have many advantages such as biodegradability, non-toxicity, the ability to undergo various chemical modifications, and wide availability from renewable sources. This article provides a review of synthetic and biobased flocculants and lists their potential applications in water treatment. Based on the up-to-date data, a new approach is proposed for searching for modified and grafted flocculants, flocculation mechanisms, test methods, and factors influencing this process. Particular attention is paid to flocculants based on chitosan and its derivatives, since they are cheap and environmentally friendly materials used in industrial practice.

Keywords

• polymers
• chitosan
• flocculation
• bridging
• neutralization
• environment