How is Landfill Leachate Water Treated?
Current Issues – Landfill Solid Waste Pollution & Leachate
The consistent increase of global human population coupled with changing lifestyles have lead to vast amounts of solid waste pollution, which causes resources depletion with a seriously negative environmental impact.
Even though many methods have been utilized to overcome this solid waste pollution problem issue such as recycling and reuse, the landfilling process is still one of the primary ways for the disposal of solid waste. However, the production of leachate from this process is among the main drawbacks of this method and it has become a serious threat to the environment. Landfill leachate is a complex combination pollutant of concern, consisting of heavy metals, color, as well as inorganic and inorganic components. Some of these compounds are toxic and refractory in nature.
Methods of Treating Leachate Water
It is well known that biological treatment can be among the least expensive treatment methods for wastewater treatment. However, the presence of the contaminants in landfill leachate, including non-biodegradable organic pollutants inhibit the performance of this technique. Selection of a suitable method for landfill leachate treatment basically depends on the composition of the leachate solution.
Various techniques have been utilized for the treatment of landfill leachate water, including adsorption, electro-oxidation, biological, and advanced oxidation.
Several of these techniques suffer certain drawbacks when used for primary treatment of this type of wastewater. For instance, the adsorption method is a very slow process with low efficiency, the electrochemical oxidation process is selective and can suffer from the electrode passivation process; and the advanced oxidation process can be costly requiring specific storage tanks for oxidant reagents.
The conventional chemical coagulation technique also has several limitations as well. Chemicals used for this method include alum and other metal salts. Among the main disadvantages of this method is both the operational costs and the high levels of solids sludge generation and its environmental impact.
Specialized Electrocoagulation for Leachate Treatment
Electrocoagulation treatment has gained immense attention over recent years for many reasons including the relative ease of operation and automation.
This process does not require any chemical addition, and has simplicity of equipment, relatively short retention times and low sludge generation rates.
Additionally, the typical higher salinity in leachate solutions leads to a reduction in the electrical energy consumed during this treatment process.
Treatment Process
In the typical advanced GWT treatment process, primary treatment consists of specialized electrochemical treatment, followed by the utilization of Zeoturb liquid bio-organic flocculant which is further treated by post polishing filtration and disinfection as required that allows for the discharge of the leachate solution with minimal environmental impact.
Interested to learn more about how specialized electrocoagulation and the advanced GWT treatment process can assist your organization landfill water treatment?
Contact the water & wastewater experts at Genesis Water Technologies, Inc. at +1 877 267 3699 or reach out to us via email at customersupport@genesiswatertech.com to discuss your specific situation.
Application Case Study:
Challenge:
A large conglomerate managing many municipal landfills for government entities in India wanted to both reduce their operating costs of treating the generated landfill leachate solutions generated. Additionally, they wanted to move toward more sustainable methods that can provide higher quality effluent that could be discharged with minimal environmental impact to surface water.
Genesis Water Technologies (GWT) bench tested with third party lab validation two different GWT treatment methods on landfill leachate solutions samples provided by this client. GWT optimized the water quality to meet standards that will enable them to sustainable discharge the treated effluent to surface water with minimal environmental impact.
The below feed water consisted of elevated levels of COD, BOD, TOC, TSS, Color as well as certain heavy metals.
Solution:
Genesis Water Technologies conducted bench tests on multiple samples of the clients landfill leachate water from several of their existing landfills.
These bench tests included the utilizing of our specialized electrocoagulation system followed by post treatment clarification using our Zeoturb bio-organic flocculant with post polishing filtration.
GWT tested several process configuration combinations including using both electrocoagulation with Zeoturb bio-organic flocculant and without, different treatment intervals, and different post polishing filtration.
Final process optimization adjustments would occur upon scale up to the commercial flow rates of 1500-2000 m3/d (276-370gpm) required for sustainable discharge within regulatory requirements.
Subsequent to this testing, plans to establish a reuse facility to handle their reuse water would be the next steps.
Results:
The results obtained from the post treatability optimized treatment process indicated reductions of turbidity to less than < 5 NTU, iron was reduced to less than 1 mg/l, with total suspended solids
reduced to less than 1 mg/l and validated by third party lab testing.
Additionally other mineral contaminants were within an acceptable range for the client based on their specific applicable application.