Solidification/stabilization of landfill leachate concentrate using different aggregate materials

Area of Science:

• Environmental Engineering
• Waste Management
• Water Treatment Technologies

Background:

• Reverse osmosis (RO) is widely used for landfill leachate treatment in Europe and Turkey.
• A significant challenge with RO is the generation of a concentrate stream with high salt and contaminant levels.
• Current disposal methods for RO concentrate include re-infiltration, drying, incineration, and solidification/stabilization (S/S).

Purpose of the Study:

• To investigate the efficacy of solidification/stabilization (S/S) technology for treating RO concentrate from landfill leachate.
• To evaluate the use of zeolite and aggregate materials in the S/S process for pollutant absorption.
• To determine if S/S can reduce pollutant concentrations to meet landfill disposal limits.

Main Methods:

• Solidification/stabilization experiments were conducted on RO concentrate from landfill leachate.
• Zeolite and various aggregate materials were incorporated to enhance the absorption of heavy metals, ammonia, and other pollutants.
• Leachate eluate testing was performed to quantify remaining pollutants after S/S treatment.

Main Results:

• The S/S process successfully solidified major pollutants in the landfill leachate concentrate, including TOC, DOC, TDS, and ammonia.
• Post-treatment eluate water contained only approximately 1% of the initial TOC, DOC, TDS, and ammonia concentrations.
• The immobilization of pollutants achieved through S/S met the stringent requirements for landfill disposal.

Conclusions:

• Solidification/stabilization is a viable and effective technology for managing reverse osmosis concentrate from landfill leachate.
• The addition of zeolite and aggregates enhances the pollutant-binding capacity of the S/S process.
• S/S treatment allows for the safe disposal of RO concentrate, aligning with environmental regulations for landfilling.