Recycling industrial or household waste is very imperative for keeping the environment clean. Recently, researchers from the University of Bath have demonstrated an effective method of generating biofuel from waste coffee grounds that can power vehicles.
Researchers employed advanced transesterification process to extract oil, which involves soaking the coffee grounds in organic solvents that separates the oil. The separated oil later undergoes a series of chemical reaction to produce biodiesel. Using the process, researchers were able to produce biofuels from caffeinated as well as decaffeinated forms, grown in 20 different geographic areas. They even used Robusta and Arabica coffee varieties for the study.
Findings from the study showed that irrespective of the source and variety of coffee bean used, the end biofuel generated had almost standard composition. This implies that all kinds of coffee bean wastes are good enough to be used as feedstock for biofuel generation.
From the Department of Chemical Engineering, Whorrod Research Fellow, Dr Chris Chuck explained that global annual coffee production is of about 8 million tones and 20 per cent oil is present in each unit of waste ground coffee. And oil so produced exhibit properties similar to feedstock that are used at the present to generate biofuels. But present biofuel feedstocks are grown purposefully engaging land, effort and time, whereas coffee grounds are complete waste, ready to be recycled into biodiesel.
Dr Chuck further added that growth condition of present feedstock used for biofuel generation can alter the yield and properties of biodiesel, at times rendering them fall out of acceptance criteria. But all kinds of coffee grounds are free from such issues and are known to show uniformity in the biodiesel performance.
Though in the current scenario coffee biodiesel would not be able to replace conventional fuel. However, coffee shop chains can use the process to produce fuel that can power their delivery vehicles. These vehicles apart from deliveries can also be used for collecting and transporting coffee grinds to the central facility for biodiesel generation. Researchers estimate that 10 kgs of waste coffee grounds are produced by a small coffee shop, which can produce nearly 2 liters of biofuel. Also discarded beans and waste generated by industries engaged in coffee bean roasting, can contribute substantially in biodiesel generation.
The idea has been already used by a London Based company known as bio-bean, which is generating biomass pellets and biodiesel from the waste coffee grounds. Imagine if big coffee chains like Starbucks and Costa join the initiative, they could soon become a top biodiesel generating company in the future, giving tough competition to giant oil companies. So it may not be far when we would start refueling our vehicles using biodiesel produced from waste coffee grounds, an interesting idea indeed. 🙂
Source: University of Bath