Landfill leachate is simply defined as the liquid that drains or ‘leaches’ from a landfill. In order to protect groundwater and surface water from contamination, municipalities and industrial waste disposal facilities employ various technologies to minimize leachate volumes and purify leachate for reuse. Common methods of treating landfill leachate include various types of biological and physical/chemical processes:
- Aerobic Biological
- Anaerobic Biological
- Carbon Adsorption
- Chemical Precipitation
- Multimedia Filtration
- Reverse Osmosis/DTRO
- Solids Concentration or Dewatering
However, the above processes require extensive pretreatment and frequent cleaning procedures, resulting in high capital (CAPEX) and operational (OPEX) costs.
The OsmoBC™ system from FTS utilizes the company’s innovative OsmoF2O™ FO membrane elements, designed to treat high-fouling feed streams requiring only minimal pretreatment. FTS provides a 100-micron disk filter(INTEGRA™) to remove larger suspended solids and provide pH adjustment if necessary.A sodium chloride solution is used as a Draw Solution(DS). At typical wastewater solution strengths, a concentration factor of 5-20 is achieved with FO, with permeate recoveries of 80% to 95%.
FTS’ unique HBCR™ Brine Concentrator system extracts the water from the brine, and the reconstituted brine is returned to the FO system.The quality of the resulting permeate is improved by using second- or even third-pass HBCR Brine Concentrator systems. When the fouling organics and inorganics begin to come out of solution as the waste stream is concentrated, the foulants can be removed and membrane performance recovered by simple osmotic backwashing and flushing.
The final permeate can be discharged to nature or used for process water or irrigation. The final effluent has consistently met stringent permit limits, which are based on regional and country’s freshwater quality standards.Concentrate can be solidified (crystallized) and returned to a landfill or discarded via other disposal options.