What is solid waste?

When a product is no longer useful or serves the same purpose for which it was manufactured, it becomes waste. There are many types of waste, but today we're going to focus on solid waste , which is mostly produced in urban areas, although it's also found in other sectors such as industrial and commercial settings. These are products that have already fulfilled their function and, in some cases, have lost almost all their economic value.
These solid wastes, also referred to as municipal solid waste (MSW) , can have various destinations: landfill, incineration, or recycling. Each of these options has advantages and disadvantages, since, for example, incineration can reduce the volume of waste but generate pollutants. However, recycling offers a second life to many materials. In addition, some wastes, after decomposing in a landfill, produce biogas , which can be used for energy production.
Solid waste classification

There are several ways to classify solid waste depending on its hazardousness, biodegradability or composition. Classification is essential to understand how to handle it properly and minimize environmental impact.
- Dangerous residues: Those that represent a risk to health or the environment due to their toxic, flammable, corrosive or explosive properties. These include chemical or industrial waste.
- Non-hazardous waste: Those that do not present an immediate risk to health or the environment. They are subdivided into:
- Ordinaries: They are generated in daily activities in homes, offices, hospitals, etc., such as paper, cardboard or packaging.
- Biodegradable: Those that decompose naturally, such as food or vegetable scraps.
- inert: Waste that takes a long time to decompose, such as metals or glass.
- Recyclables: These are those that can be reincorporated into the production cycle, such as plastic or glass.
An additional classification that is usually made is the following:
- Organic: Mainly biodegradable waste, which comes from natural products or food.
- Inorganic: Man-made products that take years or decades to decompose, such as plastic or metal.
Solid waste management
Solid waste management involves a series of stages that begin with collection, transportation, storage and finally treatment or disposal of the waste. For efficient and sustainable management, segregation is key to reducing the amount of waste that ends up in landfills.
There are several ways to manage solid waste:
- Sanitary landfill: It is a common technique for burying hazardous waste underground, in specific areas designed to minimize the risk of contamination to air or water.
- Incineration: It is the burning of waste at high temperatures, which drastically reduces its volume. However, it can generate polluting emissions, such as ash and toxic gases.
- Separation and utilization: This method allows valuable materials to be recovered from waste for reuse or recycling.
Consequences of poor management
Irresponsible management of solid waste can have serious consequences for both people and the environment. Globally, poor waste management generates pollution in soil, water and the atmosphere, affecting flora and fauna and multiplying the risk of human diseases.
- Air pollution: Particularly in the case of incineration, the release of carbon dioxide and other gases aggravates climate change.
- Water and soil pollution: Leachate from poorly managed landfills contaminates drinking water sources and soils, affecting both animals and crops.
- Public health problems: Poorly managed waste is also a breeding ground for diseases such as dengue, cholera and malaria.
It is therefore vital that both citizens and industries participate in the classification and proper management of waste from the initial stages.
Understanding the type of waste we generate, how to classify it and the best ways to manage it is a key step towards a cleaner and healthier planet.