How to treat and dispose of solid waste through Sanitary Landfills?
The most popular management technique for municipal solid waste is land disposal.
A sanitary landfill, a disposal location that has been carefully chosen, developed, built, and maintained, is where refuse can be securely dumped. In this article, we will learn how solid waste is disposed of in landfills, and how it is treated at the same location.
The fact that the buried waste is never in contact with groundwater or surface water, is one of the most crucial aspects of landfilling.
There must be a minimum distance between the landfill's bottom and the groundwater table, which is seasonally high, according to engineering design specifications. Most brand-new landfills must feature a system of groundwater monitoring wells, and an impermeable liner or barrier at the bottom.
To prevent precipitation or surface runoff from damaging the buried waste, completed landfill sections must be covered with an impermeable lid. Liners for the bottom and cap may be composed of clay soil layers, flexible plastic membranes, or a combination of the two.
Building the landfill
Step 1:The waste cell is the fundamental component of a sanitary landfill. Refuse is spread out and compacted in thin layers in this small, enclosed area of the site. A maximum of three metres' worth of layers can be compressed on top of one another (10 feet).The volume of the compacted waste is around one-fourth that of the loose waste.
Step 2:To get rid of odours, insects, and rodent issues, a layer of earth is placed over the waste at the end of each day's operations. Thus, the daily volume of compacted waste and soil cover is contained, within one garbage cell.
Step 3:A lift is made up of several neighbouring waste cells, and eventually a landfill may have two or more lifts, stacked on top of one another. A topsoil layer that can support vegetative growth may also be placed on top of the landfill's final cap.
Step 4:Daily cover soil may be brought in and stockpiled from sources off-site, or it may be available locally. The waste and dirt are dispersed and compacted using a variety of heavy equipment, such as rubber-tired dozers or crawler tractors. To accomplish high-density compaction of the waste, heavy steel-wheeled compactors may also be used.
Step 5:A new landfill's dimensions are precisely marked, and the base is ready for the building of any necessary liners and leachate-collection systems. To protect it from garbage vehicles, at least 30 cm (12 inches) of sand must be properly put over, any plastic liners utilized.
Step 6:The trench technique of building may be used at locations, where excavations can be done below grade. When geography or groundwater issues make this impractical, the area approach may be used, resulting in a mound or hill growing over the original ground. The area approach doesn't need any ground excavation, so dirt must typically be transported from somewhere to the site.
Step 7:The finished landfill finally melds into the surroundings.
Benefit and limitations of disposal of solid waste in landfills
Advantage: If landfills are properly managed, they provide a safe way to dispose of waste.
Limitation: It needs a sizable amount of space.
Anaerobic microbial activity causes organic waste that has been buried in a landfill to disintegrate. In most cases, complete disintegration takes longer than 20 years.
Methane gas is one of the by-products of this breakdown. Methane is a powerful greenhouse gas that is explosive and toxic, when diluted in the air. It can also move through permeable soil layers over great distances, and if it is allowed to build up in basements or other small spaces, deadly situations may develop.
Methane migration is regulated in contemporary landfills by gas-venting systems, and impermeable barriers. Methane gas is sometimes recovered from landfills and used as fuel, either directly or as a component of biogas.
Leachate is another by-product of decomposition in sanitary landfills, and it is a highly contaminated liquid. Runoff that enters the waste cells and comes into touch with decaying wastes, produces the majority of leachate.
Leachate can cause major environmental pollution issues, including the potential poisoning of drinking water supplies, if it seeps into the ground or enters the groundwater. Surface water can be intercepted to keep it out of the landfill, and impermeable liners or barriers can be used, to separate the waste from groundwater to limit leachate. Additionally, groundwater monitoring wells, and leachate collection and treatment systems, ought to be installed at new landfill sites.
Importance in the management of solid waste
Sanitary landfills often offer the most cost-effective solution for non-recyclable waste disposal, in places where suitable sites are readily available. Finding locations, though, that provide sufficient capacity, accessibility, and environmental conditions, is become more and more challenging.
However, landfills will always be important to the management of solid waste. Not all parts of solid waste can be recycled, and there will always be leftovers after incineration and other treatment procedures, which will eventually need to be buried. Furthermore, landfills can really make bad land better. In some localities, legally finished landfills are transformed into play areas, parks, or golf courses.
Modern landfills are constructed with an impervious liner covering the bottom, which is often made of multiple layers of thick plastic and sand. Through leaching or percolation, this liner guards against contamination of the groundwater.
How can we assist?
The system designers at Netsol Water will be able to assess, all needs for the client, and select the most efficient, practical, and modern solid waste management technique, for municipalities, residential areas, commercial areas, as well as industries, which includes sanitary landfilling as well.