Leachate treatment is a significant problem for landfill operators. Landfill leachate is mainly caused by percolation of water through the landfilled waste, degradation processes inside the landfill and waste with high water content. The water sources are the infiltration of rainwater, surface water, and groundwater due to inadequate impermeabilization of the landfill.

Typically, leachate from waste treatment and disposal facilities, like landfills and mechanical and biological treatment (MBT) plants, is very complex wastewater and must be treated according to local legal requirements before it can be discharged into a water body or sewer network. Leachate is heavily contaminated with organic substances, nitrogen, heavy metals and salts.

Treatment of landfill leachate is technically a challenge due to its high composition variability and high production fluctuation. Economically it represents a high cost of waste treatment, in the range of 20-30% of the total cost. It is a non-core business activity for the operator of a landfill site.

AST’s specialized team has worked for more than 25 years with landfill leachate and other industrial wastewater, applying different and tailor-made technologies.


Reverse Osmosis 

The main technology applied in landfill leachate treatment is Reverse Osmosis (RO) due to its simplicity, robustness, and efficiency.

Reverse osmosis is a physical filtration technique in which pollutants are removed from liquid fluids using semi-permeable membranes. Due to the small size and nature of the membranes, suspended solids, molecules and some ions are segregated, and a permeate, the treated water with the highest quality, is produced and can be used as process water or adequately discharged.

AST develops, builds and operates high-end compact RO plants to treat landfill leachate most efficiently and economically, providing leading recovery and reliability. Assembled in mobile units and inside maritime containers or in trailers, these systems have a treatment capacity that can vary from 30 to 400 m³ per day and unit. AST RO units can be configured with 2 or 3 membrane stages depending on the leachate characteristics and required discharge quality. 

Our portfolio also includes brine concentration RO units for a further reduction of discharge volume, decreasing the size and cost in the case of downstream evaporators. 

Our specific spiral wound membrane modules are highly resistant and provide the best recovery together with the best shelf life and economy. 

Our RO systems for leachate treatment are available in two pressure classes:

  • 1200 (HPRO) – operating with 1200 psi (82 bar), concentrates up to 80,000 mg/L TDS.
  • 1800 (UHPRO) – operates at 1800 psi (120 bar), concentrates brine up to 130,000 mg/L TDS.

Our plants incorporate AST systems and high-quality materials and components from brand manufacturers.

AST RO plants have low energy consumption and are equipped with high-efficiency membranes and automatic cleaning systems.

All AST plants are built, pre-commissioned and tested in our factory.



AST designs biological leachate treatment solutions, including high-performance Sequencing Batch Reactors (SBR) and Membrane Bioreactor (MBR) with final purification steps, and provides the critical components for these solutions.

Complementary Systems

In case of excessive concentration of specific pollutants, AST provides particular solutions for the removal so that the other purification systems as RO, can operate with maximum recovery. For these cases, Microfiltration (MF), Ultrafiltration (UF), and chemical and physical treatment (Flotation) can be applied.


For the maximum reduction of brine (concentrate), AST provides proven and cost-effective thermal brine management systems. 

Rental RO plants

AST is providing RO rental plants to help clients resolve leachate production peaks and empty lagoons for cleaning. 

Talk to us if you need a temporary solution for your landfill site!