Each cup of coffee produces coffee grounds that are often thrown away, even though many recycling solutions exist. This waste represents about 20 million tons in the world each year. It is therefore time and necessary to recycle coffee grounds and to valorize them, especially since they are 100% recyclable and constitute a natural fertilizer.

How is coffee grounds collected ?

For a larger scale recycling, coffee grounds go through several different stages depending on whether they are collected raw or in the form of capsules:

• For professionals in the restaurant, hotel and business sectors, coffee grounds are collected by companies specializing in the recovery of biomass and the production of biofuels.

• For private individuals, whether it be coffee pods, aluminum capsules or bulk coffee, the waste collection centers ensure collection and sorting. The coffee grounds are then sent to the most appropriate channel for recycling.

The treatment of coffee grounds

Collected in bulk, the coffee grounds are weighed before quality control. This makes it possible to check that it has not been mixed with other waste. Then, the coffee grounds will join the existing stock on the place of treatment:

• The stages of maturation and transformation make it an organic and natural fertilizer to fertilize the soil. It is very commonly used by mushroom growers, especially for the cultivation of oyster mushrooms.
• It is also possible to recycle coffee grounds through the methanization process. A natural solution used to produce biogas and green electricity.

Coffee grounds in capsules

For coffee grounds collected in capsules, the transformation process is more complex, but recycling has evolved considerably and is now carried out according to a well-established chain. The aluminum or plastic capsules are recovered by the major brands that manufacture them or by recycling centers. Some regions of France collect them through the yellow bags for steel and aluminum.

Once separated from the aluminum or plastic, the coffee grounds are sent to a specialized center to join those in bulk and benefit from the same treatment.

A natural fertilizer

To give coffee grounds a second life, the easiest and fastest technique is to use them in your garden as compost. Rich in nutrients, it will be ideal for making the soil more fertile and for growing plants or vegetables. An ecological solution to easily dispose of coffee grounds.

Other ways to recycle coffee grounds

A culture medium for mushrooms

Coffee grounds contain lignocellulose which allows the growth of mushrooms, especially oyster mushrooms. There are different techniques, one of the most common being to mix mycelium with cardboard, wood shavings and coffee grounds, then wrap this medium in a long plastic bag. Hanging vertically in the dark, the bags should “incubate” for two weeks in the dark and in a humid environment. Hidden in the dark, the mycelium will develop, just like under the roots of a tree. After two weeks, the bags, which have become completely white, are transferred to the light and incised to allow the oyster mushrooms to emerge.

In vermicomposting

Coffee grounds are a good structuring agent for vermicompost, and they also help in the digestion of the worms because the coffee beans act as a grinder in the worm’s belly. Coffee will also have a positive effect on worm reproduction.

A super degreaser

Coffee grounds are a very good degreaser, so they can be used as a natural cleaner to remove stubborn grease stains from dishes. Its low abrasion will also clean tough cooking stains. Simply mix 2/3 teaspoons of coffee grounds with warm water and scrub with a sponge or soft brush to clean dishes.

A natural scrub

Coffee grounds act as an exfoliant thanks to the fine, slightly abrasive particles they contain. It is particularly effective for scrubs. Apply it to your wet skin in the shower, massage gently and rinse.