Waste - Know Definition, Sources of Waste and its Types

1. Waste is described as undesired and unusable materials, and it is considered a useless substance. It can also be defined as any substance that is dumped after its primary use, or for which there is no further use, is referred to as waste.
2. Natural ecosystems also produce waste (oxygen, carbon dioxide, dead organic matter), but they get recycled quickly.
3. Waste management is a serious issue in today’s world. The major principle of waste management is the 3R’s: Reduce, Reuse and Recycle.
4. In our daily lives, we produce large amounts of waste which don’t decompose easily. It is important to understand the different categories of waste and their source to address issues like pollution and hygiene in our communities.

Sources of Waste

1) Urban/ Domestic waste

1. The waste collected from households, markets, streets, etc comes under the category of urban or domestic waste.
2. It is usually the responsibility of the local authority to collect and deal with this waste. It can be garbage from houses, refuse material like leaves and plastic on the streets, etc.
3. The issue with this source is that most of the time, the collected waste is a mixture of organic waste, batteries, plastic, etc. There will be combustible and non-combustible material.
4. Urban sources might also have metal waste, construction waste, carcasses of animals, sludge etc.

To know more about Solid Waste Management, click here.

2) Industrial waste

1. It can be in the form of solid, liquid, or gas.
2. It can be released from chemical factories, thermal power plants, paint factories, manufacturing industries, etc.
3. The major characteristic of waste from industries is their high level of toxic content. They are also a major contributor to different kinds of pollution.

Know in-depth about wastewater here. They are broadly classified into hazardous and non-hazardous waste:

1. Hazardous waste- Mainly in industries that produce or utilize chemical components in large quantities like rubber, metal, pharmaceuticals, etc.
2. Non-hazardous waste- Such waste comes from food processing and other organic industries. But even their discharge into rivers can become hazardous if beyond certain limits.

3) Agricultural waste

1. It refers to residue generated as a result of agricultural activities. Remains of damaged crops, pesticide runoff, unusable by-products, etc are the major components.
2. New methods of farming like organic farming try to ensure that organic waste produced goes back into the farming process for making beds, increasing the nutrient content of soil, etc.
3. The sludge from poultry farms and cattle houses may also contribute to the waste generated. Integrated farming models envision farms where poultry and cattle can provide manure.

4) Commercial waste

1. This is waste from commercial establishments like hotels, theatres, workplaces etc that get generated in massive quantities on a day-to-day basis.
2. Paper, food, plastic, and even toxins are examples of commercial waste.

Apart from these sources, there are sources like mining, radioactive waste sources, electronic sources and biomedical sources of waste.

Types of Waste

Organic Waste

• Organic waste is any biodegradable material derived from a plant or an animal.
• Organic waste that degrades into carbon dioxide, methane, or simple organic molecules is referred to as biodegradable waste.
• Green waste, food waste, wood trash, green garbage, and landscaping and pruning waste are all examples of organic waste.
• When organic waste is disposed of in landfills, it decomposes anaerobically (because of a lack of oxygen) and emits methane. Methane is a 20 times more powerful greenhouse gas than carbon dioxide when discharged into the atmosphere.
• Recycling organics decreases greenhouse gas emissions while conserving natural resources.

• Composting is a controlled process that uses microorganisms found naturally in organic waste and soil to break down organic material. These bacteria require basic nutrition, oxygen, and water in order to decompose at a rapid rate.
• The majority of organic waste created by a greenhouse may be composted. Large amounts of debris must be shredded before being placed in a well-built compost pile.
• Compost is a dark brown, hummus-like substance that may be readily handled, stored, and utilized as a beneficial natural fertilizer.
• Degradation agents might be based on physical decomposition (such as earthworms and dung beetles) or chemical breakdown (like bacteria and fungi).
• Decomposition rates and time required to achieve a stable product are affected by oxygen and moisture levels during composting. Composting is hampered by oxygen levels below 5% and moisture levels above or below the 40-65 percent range.
• The term "biodegradable" does not always imply that it can be composted at all types of composting facilities.
• Some biodegradable materials may not degrade quickly enough when composted at a slower rate and, like conventional plastics, can be deemed pollutants. Many high-rate technologies, on the other hand, will be able to handle both biodegradable and compostable polymers.

Learn more about Pollution and its types, here.

Plastic Waste

• Plastic is used in nearly every industry, including consumer products packaging, machinery, transportation etc. It is flexible, versatile, light and durable.
• The packaging industry is the largest consumer of plastics. It allows flexibility in design and shape. The food industry depends heavily on plastic for increasing shelf life and reducing food wastage.
• The deposition of plastic objects and particles (such as plastic bottles, toys etc.) in the Earth's environment is referred to as plastic pollution.
• The chemical composition of most plastics renders them resistant to natural decomposition. As a result, plastic pollutants stay in the soil for a long time.
• Plastic pollution is a major threat to the health of marine ecosystems. Almost 8 million tonnes of plastic ultimately end up in our seas each year. Some studies estimate that by 2025, this amount will have doubled, while others estimate that by 2050, there will be more plastic in our seas than fish.
• Aquatic organisms can become entangled in plastic objects (such as plastic bags), consume the plastic, or be exposed to plastic toxins, all of which can cause biological changes over time.
• Presently, China is now the leading producer of plastic waste.
• Bioplastics are made from plant-based materials, yet the end product is no better than any other plastic.
• Plastics that degrade naturally into carbon dioxide, water, and minerals are known as biodegradable plastics. To get certified as biodegradable plastic, 90% of the material has to degrade into CO2 within 6 months after being exposed to sunlight.

Read about the International Plastic Bag Free Day here.

Glass Waste

• Glass is mainly found in Municipal Solid Waste in the form of liquor bottles, containers, tubelights, vessels, etc.
• Glass is usually crushed and remelted into other products. The form of crushed glass is called a cullet.
• It is usually collected back through Material Recovery Facilities (MRFs) or recycling machines.
• Glass recycling has traditionally entailed collecting and sorting glass by color for use in the production of new glass containers. However, the high cost of collecting and processing limits the ability to recycle glass from MSW. The difference in the material specifications also affects recyclability and reusability.
• As a substitute for aggregate in asphalt paving, waste glass has been utilized in road building.
• The properties of crushed glass or cullet, when appropriately sized and treated, can be comparable to those of sand.
• Increased usage of recycled glass waste would result in greater energy and cost savings, as well as a reduction in the amount of waste created in the sector.

Study about Soil Pollution here.

Metal Waste

• Each and every day, industrial operations employ a variety of metals in huge quantities. We've seen our consumption levels soar since the Industrial Revolution, thanks to mass manufacturing and low unit prices.
• Aluminum is the most widely used metal in the world, followed by copper, zinc, lead, and nickel. Furthermore, precious metals such as gold are utilized in the manufacturing of computers and other electrical equipment.
• Metals are limited resources. Metal depletion may become a major concern in the future as the world population rises quickly, increasing demand for metal-based commodities.
• The benefit of metal recycling is that metal may be recycled repeatedly without losing its characteristics.
• Metal waste is produced by a wide range of industrial activities. In many situations, precise end-product forms are necessary. However, in order to get this form, the remaining material must be separated.
• To continue current consumption patterns, which entail substantial volumes of metal consumption, we must make metal recycling systems extremely efficient.

Also, check out more Water Treatment, here.

Electronic Waste

• E-waste is a term used to describe electronic items that are outdated, or are reaching or have reached the end of their "useful life." Consumer electronic items include computer monitors, televisions, VCRs, stereos, mobile phones and stereos.
• These types of waste covers both functional and damaged objects that are thrown away.
• Technological innovations are coming at us at such a breakneck pace that many electrical gadgets that still operate perfectly are considered outdated. The switchover to new tech is generating vast amounts of e-waste in every household.
• There are a wide variety of hazardous elements found in electronic devices. These include beryllium, cadmium, americium, mercury, lead, etc.

• As for global e-waste amounts, it is difficult to quantify, but large volumes end up in places where recycling facilities have not yet been established.
• Fairly basic methods are used to recover valuable components, whereas hazardous elements are disposed of in landfills. In addition to the obvious health and environmental issues, this raises questions regarding resource efficiency.
• The Basel Convention, an international convention that aims to minimize the transportation of hazardous waste between states and to prohibit the export of hazardous materials from developed to less-developed nations.
• Guangdong's Guiyu is a large electronic waste processing center in China. It is commonly called the e-waste capital of the world.

Know more about the causes of water pollution here.

Paper Waste

• In the decades from 2010 to 2060, pulp and paper consumption worldwide is anticipated to double. Growing paper production will also put further strain on the already-crippling forests across the world, and the situation is only getting worse.
• Harvesting of pulp wood threatens some of the last natural forests as well as the animals and communities that depend on them. Already, more than half of the once-vast woods have disappeared. Every year, another 13 million hectares are lost to human activity.
• In order to manufacture 1 kilogram of paper, 324 litres of water are required.
• More acreage is required for garbage containment as landfill capacity grows. As a result of the requirement to burn wastes, air pollution follows. From open and covered landfills, paper leaches toxins into the soil, causing environmental harm.
• Recycling paper conserves oil and energy, and reduces air and water pollution, according to the Environmental Protection Agency. Our forest ecosystems may also be saved. However, recycling alone is not enough.
• Trees are saved and waste is reduced by reusing paper shopping bags or switching to natural fibre bags. Further waste reduction can be achieved by reducing the usage of disposable paper goods.
• Due to the fact that paper fibre includes carbon (which was originally absorbed by the tree from which it was made), recycling keeps the carbon locked up and out of the atmosphere for extended periods of time.

Read more about Noise Pollution, here.

Nuclear Waste

• Like all industries and energy-producing technologies, the use of nuclear energy results in some waste products.
• There are three types of nuclear waste, classified according to their radioactivity: low-, intermediate-, and high-level.
• Just 3% of garbage from nuclear plants contains 95% of radioactivity.
• Nuclear power plants with outputs of more than a thousand megawatts create just three cubic meters of vitrified high-level waste each year, if the spent fuel is recycled. A 1,000-megawatt coal-fired power plant, on the other hand, produces roughly 300,000 tons of ash and more than 6 million tons of carbon dioxide annually
• Radiation from nuclear power is primarily contained in the fuel that was used to create it. Because of this, spent fuel is categorized as high-level radioactive waste (HRW).
• Used fuel is moved and stored in dry casks, which are enormous steel-reinforced concrete containers. Until a permanent disposal site is found, these barrels are meant for long-term storage.
• Thus, waste becomes less radioactive and safer to handle over time as the radioactive components decay into more stable elements.
• The half-life of a radioactive element, also known as a nuclide or isotope, determines how long it takes for radioactive elements to decay.

Conclusion

Development and rapid industrialization have led to the production of enormous waste. Improper waste disposal causes several ecological and social issues, such as trash accumulation in densely populated regions, disposal of urban sewage and industrial wastes released into rivers, and so on, all of which have an impact on the soil, air, and water ecosystems. Chemical, biological, and explosive wastes endanger the lives of humans, plants, and animals in the short and long term. Hope this article helped you to learn about Waste. If you are looking for interactive preparation for competitive exams, try the Testbook App.