Growing concerns around the presence of Per- and Polyfluoroalkyl Substances (PFAS), and their potential harmful health effects are driving unprecedented changes in how landfill leachate is managed. Increasingly, landfills are being cut off from historical outlets as publicly owned treatment works (POTWs) are under increasing pressure to reduce PFAS loading in their discharge of wastewater and biosolids. Conventional wastewater biological treatment and disinfection are not effective in reducing influent PFAS concentrations in the discharge. As regulations on PFAS compounds evolve, there is more uncertainty for landfill managers who must now consider the need for onsite leachate treatment.

The ability to concentrate and isolate PFAS compounds from complex leachate streams mitigates environmental risks, returns clean water vapor to the environment, and offers a zero liquid discharge (ZLD) solution in which a small-volume, concentrated residuals stream is safely retained in the landfill or prepared for treatment by PFAS destruction technologies. 

Technology

Heartland Concentrator

Several design elements of the Heartland Concentrator™ enable an efficient process for separation of PFAS into a small-volume residuals stream.

1. Evaporation Zone and Operational Temperature: By maintaining a wetted environment in the evaporation zone, PFAS are retained in liquid droplets, minimizing volatilization to the vapor phase by providing a “home” for the compounds to reside.

2. High Efficiency Mist Elimination: Each stage of the mist elimination system sequentially removes smaller droplets, resulting in >99% overall removal of the droplet volume at the exit of the final stage.

3. Operational pH and Suspended Solids: The Heartland Concentrator™ operates in a pH range of 6.5 to 8.5. Within this range, PFAS are generally in their non-volatile ionic form, and therefore remain in the concentrated liquid residuals generated by the system. Additionally, residuals produced from evaporation of landfill leachate often contain elevated concentrations of organic total suspended solids (TSS), and sampling indicates PFAS have an affinity for these organic substances.

Benefits of Evaporation

• Proven PFAS Sequestration: Testing has demonstrated that PFAS is retained in Heartland’s concentrated residual.

• Volume Reduction: Unlike other PFAS treatment technologies, evaporation reduces the volume of landfill leachate, generally by more than 95%.

• Clean Water Returned to the Environment: During the evaporative process, clean water vapor is released to the atmosphere and returned to the environment.

• Zero Liquid Discharge Solution (ZLD): Leachate contaminants, including PFAS, are retained in the residual and returned to the landfill. By retaining the concentrate safely in the landfill, no liquid is released to the environment in a true ZLD solution.

• ESG Leadership: By eliminating the need for trucking leachate for off-site disposal, a landfill takes trucks off the road, eliminates harmful emissions, and reduces the environmental risk of spills or leakage.