Humans produce excessive amounts of waste. According to the EPA’s Advancing Sustainable Materials Management fact sheet, in 2015 the total amount of municipal solid waste produced in the United States was 262.4 million tons. On a per capita basis, 4.48 pounds of waste was produced per person per day in 2018. That trash consisted of paper, glass, rubber, plastic, metals, food, and textiles among other things.

A little over half of that trash ended up in landfills. Of the municipal waste that was put into landfills, a majority of it consisted of food, plastics, paper, rubber, leather, and textiles. Landfill leachate is created as a result of water running through this decomposing municipal waste.

Landfills are sites in large open areas of land where wastes are dumped and buried. The trash is typically stacked in layers and then compacted before a layer of either soil or wood chips is added to the top. Before any trash is dumped onto a landfill site, most landfills are required to have a lining at the bottom. In the US, this requirement is a “flexible membrane (geomembrane) overlaying two feet of compacted clay soil lining the bottom and sides of the landfill”. These liners are meant to protect the soil and groundwater from the contamination of landfill leachate.

What is Landfill Leachate?

Leachate in general, is the product of a liquid dissolving or capturing solids and other components after passing through something. That something could be any number of things within a landfill. Therefore, landfill leachate is the result of water, either from runoff or precipitation, percolating through the decomposing wastes in the landfill.

The physical appearance of landfill leachate is that of a cloudy black, yellow, and orange liquid. This liquid smells strongly, possibly due to hydrogen-, nitrogen-, and sulfur-containing compounds in the municipal waste.

On a small scale, it would be what happens if you were to toss a cup of water into a full trash can and leave it to sit for a few days. The liquid would travel through the trash before eventually settling in a smelly brown puddle at the bottom of the can.

Contaminants

The leachate contaminants could be anything from: dissolved organic matter like alcohols, acids, aldehydes, and short chain sugars, inorganic macro components like sulfate, chloride, iron, aluminium, zinc and ammonia, heavy metals like lead, nickel, copper, and mercury, and xenobiotic organic compounds such as halogenated organics, PCBs, and dioxins.

Issues from Leachate

Contamination of groundwater is the major concern with landfill leachate. If a landfill has no lining or a cracked lining, the liquid leachate can seep through the soil beneath the waste site and then into the groundwater supply. To prevent this contamination, collection and treatment solutions must be employed to reduce leachate levels in landfills.

How Can Electrocoagulation Treat Landfill Leachate?

Electrocoagulation (EC) is by no means a new idea in wastewater treatment. However, it has within the past decade or so gained significant recognition as an effective and low cost treatment method for a variety of industries and municipal applications.

Landfill leachate treatment is one of those applications, where this electrochemical technology has been utilized as part of an integrated treatment solution. With its reactions that cause both sedimentation and flocculation, it can remove or reduce multiple contaminants in a single process. It is even capable of precipitating out smaller particles that chemical treatment methods can miss.

In contrast to conventional chemical coagulation, it is not as sensitive to changes in effluent composition, and it is able to treat for a number of contaminants as mentioned above. As seen in the photo of the results from this study, EC is very effective at removing color, though it can also remove odor in many cases as well.

Though there would be further steps required to treat the landfill leachate so that the resulting water would be clean enough to discharge or reuse. This specialized EC process can be an effective process in an integrated process system to treat the leachate. The lower lifecycle cost of this electrochemical process, performance, along with its relatively easy operation render the EC process as a primary candidate for landfill leachate water.

These are reasons why Genesis Water Technologies, Inc. is a global leader in the integration of specialized electrochemical technology and a proponent of its use for both municipal and industrial treatment application. Utilizing a GWT specialized electrocoagulation system solution within an integrated treatment system for landfill leachate can allow for optimized treatment performance with the ability to reuse or sustainably discharge leachate wastewater with relatively low lifecycle costs.

This also enables the minimization of any environment impact as well from this wastewater source.

Interested in learning how Genesis Water Technologies, Inc. can implement an EC system to help you treat landfill leachate wastewater? Contact us at 1-877-267-3699 or via email at customersupport@genesiswatertech.com for a free consultation to discuss your specific application.