What is a leachate and how is it formed?

Leachate? “The liquid formed when rain water filters through wastes placed in a landfill. When this liquid comes in contact with buried wastes, it leaches, or draws out, chemicals or constituents from those wastes”.

What do you mean by leachate?

Leachate is defined as any contaminated liquid that is generated from water percolating through a solid waste disposal site, accumulating contaminants, and moving into subsurface areas.

What are the different types of leachate?

The three main categories of conventional landfill leachate treatment technologies are (1) leachate transfer, (2) biological, and (3) physicochemical methods (Renou et al., 2008).

What is leachate and why is it harmful?

‘Leachate’ is the term for the liquid pollution that seeps through a landfill’s waste pile when it rains or snows. The leachate contains all sorts of harmful chemicals, many of which are known to cause cancer or other serious harm to human health.

What causes leachate?

Leachate is produced when water filters downward through a landfill, picking up dissolved materials from the decomposing wastes. Depending on characteristics of the landfill and the wastes it contains, the leachate may be relatively harmless or extremely toxic.

What are the characteristics of leachate?

Characterization of leachate from the landfill is generally represented by the COD (Chemical Oxygen Demand), total organic carbon (TOC), Biochemical Oxygen Demand (BOD), the ratio of BOD / COD, pH, suspended solids (SS), ammonium nitrogen (NH3-N), Total Kjldahl Nitrogen (TKN), the number of bacteria, turbidity and …

What is the effect of leachate in the environment?

Leachate that escapes from a landfill can contaminate groundwater, surface waters and soil, potentially polluting the environment and harming human health.

How is leachate treated?

Leachate can be treated by biological processes, such as activated sludge. Physicochemical processes are used to remove metals, ammonia, and dissolved solids, among other parameters. Membrane separation is an effective method for clarifying mixed liquor produced during biological treatment.

How does leachate contamination happen?

How Does Leachate Contaminate the Water Supply? When waste is placed in landfills, over time the waste decomposes and sweats. This liquid, leachate, is hazardous and must be collected for disposal. Companies who manage landfills have a specialized draining system in place that collects this leachate.

What are the effect of leachate on water?

How do you control leachate?

There are many methods of leachate treatment [5] such as: Aerobic Biological Treatment such as aerated lagoons and activated sludge. Anaerobic Biological Treatment such as anaerobic lagoons, reactors. Physiochemical treatement such as air stripping, pH adjustment, chemical precipitation, oxidation, and reduction.

How is leachate removed?

What is leachate how it can be controlled?

Leachate can be controlled in lined landfills with leachate collection and storage systems. These systems typically include provisions for the drainage of leachate within the landfill and pumping the leachate to storage tanks. The stored leachate can then be trucked or pumped to a wastewater treatment plant.

What is leachate production?

Leachate production is the result of precipitation, evaporation, surface runoff, infiltration, waste. storage capacity etc. In many Northern German Landfills the measured leachate production rates. are often between 12 and 22 % (mean value: 18 %) of the annual precipitation.

What are the different phases of leachate quality?

Leachate quality Mainly two different phases can be identified in landfills during the anaerobic decomposition of waste: acid phase, which causes a decrease of pH in the leachate but high concentrations of Sardinia 2005, Tenth International Waste Management and Landfill Symposium

What is a leachate collection system?

Leachate Collection System * Purpose: (1) to collect leachate for treatment or alternative disposal and (2) to reduce the depths of leachate buildup over the low-permeability liner. Two main collection systems: Design of Leachate 1.

Why is leachate control important?

Leachate control is a very important step to receive the long-term functionality of the drainage system, to reduce treatment costs and to render possible high-tech treatment systems.