Recycling Food Waste into Fuel

In the present time, waste management is an uphill battle. But we are still not ready to understand its consequences as citizens. Millions of tons of food turn into waste yearly, producing health hazards and various environmental issues. Thousands of people get affected by waste-related diseases, but no one is ready to ponder.

In this situation, it’s an array of hope that we can produce energy from food waste, which will also reduce waste volume.

You will be shocked that Swedish has converted over 2 million tonnes of household waste to energy. So why not us?

They’re not precisely appealing food items, and old-fashioned meats and dairy products could trigger a gag reflex; however, food scraps, leftovers, food waste, and other items in your bin remain high in energy. While they are being broken down, your mouldy oranges, breadcrumbs, and rotten walnuts are packed with calorie-producing molecules like sugars, fats, starches, proteins, and organic acids. Concerning global warming, we all want to become carbon-neutral (or even just good carbon sinks), So the most reliable option is to seize and reuse all the energy trapped in your food.

In the days of old, when everyone was on farms and even urban residents had chickens and pigs to clean up slops, there was very little food waste dumped into the landfill. It was at the very minimum that the way our grandparents lived, back in the time, food waste like potato skins, gristle, and similar wastes were thrown on the compost pile, to be repurposed to the soil. We are throwing away a lot of food to the point that even eye-swivelling Brexiteers and Pope Francis are expressing concerns. A majority of the food waste that we dispose of goes to the landfill, meaning the carbon that was costing so much in terms of water, energy, and other resources to integrate into our food items is slowly returned to the atmosphere, with no one getting a benefit, except for the landfill decomposers (beetles and bugs, worms and fungi) who’s job is to consume macromolecules and then spit out carbon dioxide, water, and some methane and hydrogen sulfur.

What can we do to recover the energy we’re losing by dumping all the food we eat? One alternative is to convert it into biogas. Who is the main character in the tale of the conversion of soft spinach and crusty peanut butter into methane? It’s our dear friend’s bacteria. Not only one bacterium or even a set of bacteria. But a group works as collaborative layers (called “trophic” layers). This is a view from the helicopter of the process carried out in a large tank called an anaerobic digester. Your green waste management company collects your and thousands of others’ food waste. 

It transports it to its site, where it is packed into the temperature-controlled digester after some pre-processing. The bugs begin working on it right away. They first get to work known as hydrolyzers cut up the large molecules of waste (e.g. the starches) into smaller molecules (e.g. sugars). These simple molecules are the food source for acidogenic bacteria that produce acidic compounds, like the ones found in pickles. Another group of bugs utilize the acids and produce mainly Acetic Acid (found within vinegar), carbon dioxide and hydrogen. The methanogenic bacteria clean off the waste materials from the three other groups and generate — guess what? Methane. It is our biofuel and can be used to create heat or power turbines that produce electricity. It’s not only companies that deal with waste disposal that are investing in anaerobic digestion. Many factories are now equipped with their Anaerobic digestors on-site to turn their waste into energy that can be used.

You may be asking why “anaerobic” digestion? Anaerobic refers to “in the absence of oxygen. In other words, we’re talking about the inability to breathe oxygen. Aerobic digestion is performed by the aerobic bacteria, the same as slow-burning your waste. You oxidize (burn) those macromolecules. You produce carbon dioxide, heat, and water; however, no high-energy substances are usable, like methane, for instance, that remain after the process.

Another method for recycling waste food is to convert cooking oil into biodiesel. Companies like Olleco gather used oil for cooking from chippers Chinese as well as caffs and employ a chemical procedure to (no bacteria are involved, unfortunately) convert what would be a powerful source of waste fatbergs to fuel.

What Should we do?

As everyone knows, there is no planet B. So the only way ahead is to take care of our planet. To sustain a better environment for generations, we must not leave any stone unturned to reduce environmental hazards. 

Every Nation should utilize its best sources to convert waste into energy because it can dually benefit us.

Clearly, we can’t stop waste production, so the only solution is to shrink and channelise it correctly.

Author: Engr. Husnain SultanEnvironmental Engineer. Passionate to spread awareness regarding current and future environmental crisis.An international consultant, advisor and trainer with expertise in waste management, biomass energy, waste-to-energy, environment protection and resource conservation.

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