Posted on 09/07/2023 5:53:30 AM PDT by Red Badger
We could be producing concrete that's 30 percent stronger by processing and adding charred coffee grounds to the mix, researchers in Australia have discovered.
Their new recipe could solve multiple problems at the same time.
Every year the world produces a staggering 10 billion kilograms of coffee waste globally. Most ends up in landfills.
"The disposal of organic waste poses an environmental challenge as it emits large amounts of greenhouse gases including methane and carbon dioxide, which contribute to climate change," explains RMIT University engineer Rajeev Roychand.
With a booming construction market globally, there's also an ever increasing demand for resource intensive concrete causing another set of environmental challenges too.
"The ongoing extraction of natural sand around the world – typically taken from river beds and banks – to meet the rapidly growing demands of the construction industry has a big impact on the environment," says RMIT engineer Jie Li.
"There are critical and long-lasting challenges in maintaining a sustainable supply of sand due to the finite nature of resources and the environmental impacts of sand mining. With a circular-economy approach, we could keep organic waste out of landfill and also better preserve our natural resources like sand."
Organic products like coffee grounds can't be added directly to concrete because they leak chemicals that weaken the building material's strength. So using low energy levels the team heated coffee waste to over 350°C (around 660° F) while depriving it of oxygen.
This process is called pyrolyzing. It breaks down the organic molecules, resulting in a porous, carbon-rich charcoal called biochar, that can form bonds with and thereby incorporate itself into the cement matrix.
Roychand and colleagues also tried pyrolyzing the coffee grounds at 500°C but the resulting biochar particles were not as strong.
The researchers caution that they still need to assess the long term durability of their cement product. They're now working on testing how the hybrid coffee-cement performs under freeze/thaw cycles, water absorption, abrasions and many more stressors.
The team is also working on creating biochars from other organic waste sources, including wood, food waste and agricultural waste.
"Our research is in the early stages, but these exciting findings offer an innovative way to greatly reduce the amount of organic waste that goes to landfill," says RMIT engineer Shannon Kilmartin-Lynch.
"Inspiration for my research, from an Indigenous perspective, involves Caring for Country, ensuring there's a sustainable life cycle for all materials and avoiding things going into landfill to minimize the impact on the environment."
Their research was published in the Journal of Cleaner Production.
The pumice in the volcanic ash made the best concrete known to man. That is why Roman concrete has literally lasted 2000 years.
When I was a kid I remember my grand parents reusing the coffee grounds from the day before. They would add a little fresh coffee and a pinch of salt. They always kept their coffee in the fridge too.
But then, why does one need 1.21 gigawatts? That's a lot of amperage.
So we need yet another container for coffee grounds to put out on trash day and we need to spend even more money for garbage removal. No thank you.
And pyrolizing the coffee grounds has no impact whatsoever.
You noticed.......................
It depends on the voltage. The higher the voltage, the lower the amperage, and this the lower gauge wire required.
However, in the spirit of no free lunch, the higher the voltage, the thicker the insulation around the conductor that is required.
I don’t have to separate garbage, nor would I. And as a practical matter If you ever feel a twinge of concern based upon the latest leftist “we’re running out of landfill space” propaganda, just take a drive across Nevada (or New Mexico, Wyoming, west Texas, even the Mojave desert in California, etc.). That’ll change your perspective really quick. We have a LOT of space.
And all the energy to sort a d truck it then heat it? Seriously better than mining the local sand pit?
And all the energy to sort a d truck it then heat it? Seriously better than mining the local sand pit?
I put them on my plants - get them from the local Starbucks that puts them in a basket for anyone to take. They are acidic so favorable for most plants.
Put several bags around my lemon tree before the last hard rain several months about - and the tree is now loaded with lemons.
By the time you spend money on collection and energy to process concrete would cost an extra $1,000 a yard.
The roses love them..........................
The organic waste —> CO2 argument is just stupid.
Stop harvesting all coffee beans worldwide and what will those coffee shrubs and trees will do? Keep producing beans that drop off the plant and rot on the ground. So you have the same organic waste decomposition.
Ok, rip out all the coffee bushes and what will nature do? Other vegetation will take over, die naturally, and rot on the ground.
Imagine the cost of having everybody mail in their used coffee grounds!
Then other liberal kooks would complain about all the energy wasted collecting coffee grounds from every coffee pot and Keurig across the land.
Maybe they could raise the price of coffee to $30/pound and attach a self-addressed return envelope with every coffee bag and can. You’d mail in your grounds and get a rebate. That would make perfect sense to a liberal.
Greenhouse gases such as methane and carbon dioxide. The coffee beans were carbon dioxide a year ago because the coffee plants make the beans from carbon dioxide in the atmosphere. The methane is from anaerobic decomposition but methane is way lighter than other atmospheric gases and rises to the top of the atmosphere before being carried away by solar wind. In other words, the carbon dioxide is not produced by coffee beans and the methane is only a temporary fleeting concern. Also, while carbon is the fourth most abundant element in the atmosphere universe, it is only the 14th most abundant element in the earth’s crust due to the fact that a lot has been lost over billions of years.
2.1 GW is more than 2.8 million horsepower. That’s some kind of performance, but I’ll bet you’d go through a lot of tires.
And we are going to run out of sand
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