Green Technology – Converting Waste Food to Biogas and Biofuel

By -

Given that householders just in UK are currently wasting 7 million tons of food per year, biofuels obtained from this tons of waste could make a vast difference. If only we could feed this tons of waste into anaerobic digestion (AD) plans, this will allow us to turn it into new and renewable energy.
Some companies are capitalizing on this end, recently a London based company called Bio-bean has launched Hot Coffees, and these are barbeque coals that are obtained from waste coffee grounds. This is produced by the company at a 20,000 square foot production plant situated in Cambridgeshire, this utilizes tons of waste coffee grounds that are left by cafes and factories all over the UK. In total, 500,000 tons of coffee is wasted the whole country in a year.

Company’s founder, Arthur Kay, discovered that a certain oil can be extracted from the waste coffee, this can then be turned into biodiesel, while the leftovers can then be turned into pellets. This can then be used to feed biomass boilers. This resource is currently being under-utilized, and it’s not the only one. Companies actually have to pay to get rid of the waste materials. Here arises the scandal that waste coffee has higher calorific value as compared to wood. Hot Coffees will soon appear on the forecourts of Gas stations. And will be available for purchase in home-ware stores, later this year. Coffee is just one of these foods that can be converted to fuel using waste material.

Biogen - The Bygrave Lodge anaerobic digestion (AD) plant opened in May 2015, so almost a year after this photo was taken. The plant still doesn't appear on most maps (including Google) but the latest OS maps on show a "power station".

Breaking down of organic matter into bio-gas and bio-fertilizer is done through the process of Anaerobic digestion. The anaerobic digester used for this purpose is sealed and is an oxygen free tank. This is one of the best processes to recycle waste from food. The benefits of an AD plant are being realized by a number of large retail chains. Sainsbury is the largest chain in this category. This superstore chain now believes in recycling of food waste, all their food waste is sent to AD plants all around UK. For this, they had to sign a deal with Biffa, this company operates a ‘super AD plant’ in Staffordshire. This plant is responsible for recycling 120,000 tons of food waste in a year and is regarded as the largest one in UK.

Cooking oil is perhaps the most well-known food wasted. Companies like Greenergy are trying to process it in biodiesel production plants. Located in the port of Immingham on the east coast of the UK. This plant was constructed in 2007 by the company. The initial purpose of the plant was to process vegetable oils like rapeseed and soy. Now, the plant is dedicated to process waste oils and fats from foods like sausage rolls, pies, pastry and crisps to produce biodiesel. Firstly the oils and fats are extracted from these foods, later on they are purified at the plant. Then they are esterified into biodiesel. Scarab Distributed Energy Ltd is also a venture of the Greenergy, focusing on production of fuel and power from wasted food. This venture includes the construction of integrated waste from food, this will help in the fueling of processing facilities all around the country spread at a number of locations. This will eventually allow them to process any kind of industrial food waste, this includes sugar, starch, fat, protein and cellulose.Renewable Energy from Food Wastes (2)

According to an estimation by the United Nations’ Food and Agriculture Organization (FAO), globally speaking, a third of all food produced in the world in never consumed and is subjected to waste. This amounts to about 1.3 billion tons of waste food per year, out of which 40% is wasted by the US, costing around $165 billion. Methane is emitted from this wasted food, commonly found rotting in landfill sites. Methane is a greenhouse gas and is regarded as more harmful to global climate as compared to carbon dioxide. 3.3 billion tons of greenhouse gas is produced every year because of the food waste.
Other means of disposing organic waste are being discovered by the researchers at UC College of Engineering and Applied Science (CEAS). In 2013, Timothy C. Keener, PhD, and Drew C. McAvoy, PhD — along with fellow faculty members Pablo Campo-Moreno, PhD, San-Mou Jeng, PhD, and George Sorial, PhD, from the CEAS Department of Biomedical, Chemical, and Environmental Engineering, put forward an initiative called the Smart Cities project, this assesses the potential of the conversion of food waste to gaseous fuel, solid fuel, biodiesel and other products. Construction of a pilot plant, resulted due to this initiative. This plant managed to convert 660 pounds of food waste from the UC Centre Court Dining Centre to research. This led to the breakthrough technology that helped the researchers turn organic materials into biogas, soil conditioner or fertilizer, using the process of anaerobic digestion. Algae is also produced using the Carbon dioxide from the biogas, then this algae is used to produce lipid oils, these are then used to produce biodiesel.