Application of chemical coagulation to phosphorus removal from glyphosate wastewater

Abstract

Glyphosate, the most widely used herbicide in the world, is routinely applied to control weeds in both agricultural and urban settings. Glyphosate wastewater that has been treated with Fenton’s reagent has a high phosphorus content and has the potential to cause environmental pollution. However, the high phosphorus concentration means that it may be possible to recover phosphorus from the glyphosate-rich wastewater. To date there have been relatively few studies on phosphorus removal from glyphosate wastewater. We therefore carried out a pilot scale study to investigate phosphorus recovery from this wastewater using chemical coagulation and evaluated the effect of various parameters, such as the initial pH, reaction time, coagulant dosage and type of coagulant. The experimental results demonstrate that a total phosphorus removal efficiency of about 68% was achieved for glycine wastewater and that total phosphorus removal efficiencies from N-(Phosphonomethyl) iminodiacetic acid wastewater and wastewater containing 6% glyphosate exceeded 90% under optimal reaction conditions.