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Updated: Jun 25, 2026
11:14
Two-way Valorization of Blast Furnace Slag: Synthesis of Precipitated Calcium Carbonate and Zeolitic Heavy Metal Adsorbent
Published on: February 21, 2017
Lime treatment of stabilized leachates
S Renou1, S Poulain, J G Givaudan
1Département de Technologie Nucléaire, Commissariat à l'Energie Atomique de Cadarache, St Paul-lez-Durance Cedex 13108, France. sebastien.renou@cea.fr
Summary
Lime precipitation effectively pre-treats landfill leachate for reverse osmosis by removing inorganic compounds and high molecular weight organic macromolecules. This reduces osmotic pressure and prevents membrane fouling, enhancing treatment efficiency.
Area of Science:
- Environmental Engineering
- Water Treatment Technologies
- Chemical Engineering
Background:
- Reverse Osmosis (RO) is a key technology for treating municipal solid waste landfill leachates, but industrial-scale application is hindered by membrane fouling and high osmotic pressures.
- Humic substances in leachate are a major cause of membrane fouling, necessitating effective pre-treatment strategies.
- Lime precipitation, traditionally used for water decarbonation, shows promise for removing foulants.
Purpose of the Study:
- To investigate the physico-chemical interactions between lime and landfill leachate.
- To evaluate the potential of lime precipitation as a pre-treatment for Reverse Osmosis (RO).
- To assess the impact of lime treatment on leachate composition and its suitability for subsequent RO.
Main Methods:
- Physico-chemical analysis of landfill leachate treated with lime.
- Characterization of precipitated solids and treated water.
- Evaluation of changes in inorganic and organic fractions, including molecular weight distribution.
- Assessment of osmotic pressure reduction and fouling potential.
Main Results:
- Lime treatment efficiently removed inorganic components via decarbonation, precipitating calcium carbonate (CaCO3).
- High molecular weight organic macromolecules, such as humic acids, were effectively removed through co-precipitation.
- A stable, easily storable residue was generated, simplifying waste management.
- Significant reduction in osmotic pressure and prevention of membrane fouling were observed.
Conclusions:
- Lime precipitation is a viable and effective pre-treatment for landfill leachate prior to Reverse Osmosis.
- This method addresses key limitations of RO, namely membrane fouling and high osmotic pressures.
- The process facilitates enhanced efficiency and sustainability of leachate treatment systems.
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