Biodegradable waste facts for kids

Imagine all the things we throw away that come from nature, like leftover food, garden clippings, or even paper. This is called biodegradable waste. It's special because tiny living things, called microbes, can break it down naturally. When this happens, it turns into simpler things like carbon dioxide, water, and rich compost that helps plants grow.

This type of waste includes many things from our homes, like kitchen waste (think spoiled food or fruit peels) and garden trimmings. It also includes natural materials like ash and animal waste. When we manage biodegradable waste well, we can turn it into something useful instead of just throwing it away. This also helps protect our planet from climate change.

What is Biodegradable Waste?

Biodegradable waste is any organic matter that can be naturally broken down. This breakdown happens thanks to tiny microbes and other living things. They help change the waste into basic elements like carbon dioxide, water, and methane. They also create useful materials like compost and humus, which are great for soil.

This natural process can happen in different ways. Some common methods include composting, where waste breaks down with air, and anaerobic digestion, where it breaks down without air. Most biodegradable waste comes from plants and animals. For example, it includes food scraps, garden waste, and even some types of paper.

Sometimes, even a few non-organic materials are considered biodegradable in waste management. For instance, gypsum (found in plasterboard) can be broken down by certain bacteria in places without oxygen. This shows how many different materials can be recycled by nature's helpers!

Where Does Biodegradable Waste Come From?

You can find biodegradable waste in many places, especially in our everyday trash. This is often called municipal solid waste. It includes things like green waste (from gardens), food waste from our kitchens, and used paper. Even some special biodegradable plastics are designed to break down naturally.

Other sources of biodegradable waste include human and animal waste, manure from farms, and sewage from our homes. Waste from places like meat processing facilities is also biodegradable. If these materials are left without oxygen, they can decay and produce methane gas through a process called anaerobic digestion.

In the United Kingdom, people are getting better at managing this waste. For example, in 2018, about 7.4 million tonnes of biodegradable waste was sent to landfill. This was a decrease from 7.8 million tonnes in 2017, showing progress in reducing waste.

Collecting and Recycling Biodegradable Waste

In many developed countries, people separate biodegradable waste from other trash. This can happen in a few ways. Sometimes, special bins are collected from the curb, just for things like food scraps and garden waste. Other times, waste is sorted after it's collected. This separated waste is often called green waste.

Removing biodegradable waste from the general trash is very helpful. It means less waste goes to landfills. It also allows us to turn this waste into something useful, like compost. Composting is a natural way to recycle organic materials into a rich soil amendment.

Another way to process biodegradable waste is through anaerobic digestion. This process uses special tanks where microbes break down the waste without oxygen. It creates biogas, which can be used to make electricity, heat, or even fuel for vehicles. For example, the Swiss company Kompogas and the Danish AIKAN process use anaerobic digestion. In 2009, Kompogas produced 27 million Kwh of electricity and biogas. Their oldest lorries have driven over 1,000,000 kilometers using biogas made from household waste! While burning waste (incineration) can also create energy, anaerobic digestion is great because it also keeps the valuable nutrients in the waste, which can then be used to make compost for soil.

Turning Waste into Something Useful (Valorization)

Waste valorization means finding ways to turn waste materials into valuable new products or resources. It's like giving trash a second life!

Using Leftover Plant Parts

Crop residue includes all the parts of plants left over after harvesting, like stalks or leaves. Instead of just throwing them away, these residues can be used to make new materials, animal feed, or even energy.

Recycling Food Scraps

Food waste is a big problem, but it also offers a great opportunity. All those uneaten meals and kitchen scraps can be turned into compost or used in anaerobic digestion to create biogas. This helps reduce waste and creates new resources.

Making Resources from Human Organic Waste

Human organic waste, when treated safely and properly, can also be turned into useful resources. For example, it can be processed to create safe fertilizers that help plants grow. This careful treatment ensures it is hygienic and beneficial for the environment.

Biodegradable Waste and Our Planet

How we handle biodegradable waste has a big effect on our planet, especially when it comes to climate change.

Understanding Landfill Gas

When biodegradable waste is buried in landfills without much oxygen, it breaks down differently. This process, called anaerobic digestion, creates a mixture of gases known as landfill gas. A major part of this gas is methane. Methane is a very powerful greenhouse gas, much stronger than carbon dioxide at trapping heat in our atmosphere. This contributes to global warming. That's why it's so important to keep biodegradable waste out of landfills and process it in other ways.

Reducing Food Waste Helps

Food waste is a significant part of biodegradable waste. When we throw away food, all the energy and resources used to grow, process, and transport that food are also wasted. Plus, when food waste ends up in landfills, it produces harmful methane gas. By reducing the amount of food we waste, we can help fight climate change and save valuable resources. Simple actions like planning meals, storing food properly, and using leftovers can make a big difference.

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