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Compost, a natural fertilizer from the organic processing of waste

Article published on 21.10.11

Compost, a natural fertilizer from the organic processing of waste
A high quality natural fertilizer, compost provides the humus that soils need. Highly effective and ecological, it’s above all a way of intelligently recycling plant-based and other organic waste from our kitchens. Discover.

What do a branch, handkerchief, eggshell and dead leaves all have in common? Stop looking, they’re all things that can be in high-quality compost. A process for transforming and recycling organic material, composting uses mainly two types of waste:

  • “Carbon” waste, which includes all non-sawdust waste, paper and all biodegradable bedding material used for herbivores.
  • “Nitrogen” waste, which includes the vast majority of plant waste as well as fermentable household garbage like peelings and vegetables.

Organic waste, oxygen and a bit of patience…

Composting is certainly one of the most natural types of recycling processes there are. It happens in the open air (in a ditch or a heap) or an enclosure (silo, etc) and consists simply of organic waste transforming in the presence of the oxygen in the air. Over a total of six months (generally spring and summer), it happens in two stages:

  • Decomposition during which any still-intact organic material is attacked by high temperature bacteria (50° à 70°).
  • Maturation during which the fresh compost transforms little by little into a compost rich in humus thanks to the action of low-temperature yeast (35-45°C).

When the process finishes, the compost is ready for use. It can be used in farming as fertilizer on pastures or prior to tilling, considerably improving the structure of the soil as well as biodiversity. For domestic use, that is for gardens or market gardening, it can be used as fertilizer on flower beds or as potting soil.


Terralys treats up to 1.5 million metric tons of waste a year

Although, at face value, compost seems simple to produce, bear in mind that its quality depends on many physical and chemical conditions. To achieve a good compost, oxygen levels need to stay below 10%. Similarly, humidity must stay between 50% and 70%, and Ph between 5 and 7. Numerous standards govern the quality of the compost, particularly at industrial scale if it is to be sold with no public-health risk.

TERRALYS, the organic recycling specialist at SUEZ ENVIRONNEMENT, is responsible for waste feedstock from arrival to recycling and throughout the entire product transformation cycle. Able to process over 1,500,000 metric tons of waste a year, in 2009 TERRALYS put 200,000 tons of normalised product on the market mainly for local authorities, industrial customers and farmers. Compost still has great days ahead of it!


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The fabulous adventure of composting

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Updated on 21.11.12