Millions of tons of coffee grounds are thrown away every year; estimates say it is from 8 to 60 million tons per year. Most of them end up in landfills. Due to its abundance, researchers have spent years investigating various eco-friendly uses for used coffee grounds. Water sanitization, next-generation batteries, stronger concrete, biodiesel, 3D printer filament, shoes and even biodegradable plastics: recycled coffee grounds were used to create it all.
And now insulation has been added to that list. Scientists have found a way to turn coffee grounds into an environmentally cordial alternative to petroleum-based products such as Styrofoam and spray foam.
As reported Eurek Alertthe study is the work of researchers at Korea National Jeonbuk University and was recently published in a journal. There have been previous attempts to exploit coffee grounds as an eco-alternative for insulation, but due to their low porosity, the effectiveness of such grounds was narrow. But for the modern substance, researchers transformed used coffee grounds into biochar.
Biochar is created by exposing a substance such as coffee grounds to extremely high temperatures, creating a modern carbon-rich and highly porous material. Due to its greater porosity, biochar can retain air, providing it with better insulation against heat transfer.
The researchers added ethyl cellulose, a natural polymer made from cellulose, to the biochar and used what they call a “pore rebuilding” strategy that prevents the polymer from filling the pores of the biochar, thereby enhancing its insulating properties.
The resulting material has a thermal conductivity of “0.04 W per meter per Kelvin, a level comparable to commercially available expanded polystyrene.” A value of less than 0.07 W per meter per kelvin is considered an effective insulator, making biochar insulation “one of the most effective options”.
Like other biochar alternatives, the modern insulating compound is an ecological double whammy. It’s budget-friendly to produce, relies on materials that would otherwise end up in landfills, and replaces customary options that often require toxic chemical or industrial solvents to produce.
We are one step closer to fulfilling my dream: living in a world made of coffee. My house is built of coffee bricks on a foundation of coffee cement, the walls are lined with coffee insulation, and everything runs on a battery made of coffee. All my animals are fed with organic coffee feed and my plants with coffee compost. Everything is handsome and nothing hurts.
