Compost can be used in agricultural activities due to its various positive impacts on the physical and chemical properties of the soil, meanwhile reducing utilization of inorganic fertilizers. Composting has also negative environmental impacts, some of them of social concern. This is the case of composting atmospheric emissions, especially in the case of greenhouse gases (GHG) and certain families of volatile organic compounds (VOC).
Waste |
Main VOC Family |
Other VOCs |
Reference |
---|---|---|---|
Poultry litter |
Alkanes and alkylated benzenes |
Aldehydes, terpenes, and ketones |
[32] |
Chicken manure and biochar |
Ketones, phenols, and organic acids |
Aliphatic, aromatic, and terpenes |
[33] |
Municipal solid waste |
Alkylated benzenes, alcohols, and alkanes |
- |
[14] |
Wastewater sludge |
Terpenes |
Furans and esters |
[34] |
Digested wastewater sludge |
Terpenes |
Alcohols and Ketones |
[34] |
Swine carcass |
Sulphur compounds |
- |
[35] |
Municipal solid waste |
Terpenes |
Alcohols, volatile fatty acids, and aromatic compounds |
[36] |
Livestock and Poultry Manure |
Sulfur compounds, aliphatic hydrocarbons, aromatic hydrocarbons |
Chlorinated organic compounds |
[37] |
Municipal solid waste digestate |
Terpenes and oxygenated compounds |
Sulphur compounds and methanethiol |
[38] |
Green waste |
Alcohols |
Alkenes, aliphatic alkanes, aromatic hydrocarbons, ketones, aldehydes, furans, and esters |
[39] |
Sewage sludge |
Isovaleraldehyde, butyric acid, sulphur compounds, and pinene |
Indole, skatole, and phenol |
[40] |
Composting is a favorable technology to treat organic waste, but gaseous emissions are an issue of major concern for its development. Among them, GHG emissions are an important problem as they are responsible for the global warming effect. Carbon dioxide is not often considered, as it is considered biogenic. However, methane and nitrous oxide, related to anaerobic and anoxic conditions, must be accounted for when analyzing any composting process. Another important point is the release in the form of gaseous emissions of a vast family of compounds such as VOCs. These gases can be harmful, possess negative impacts, and, especially, are responsible for unpleasant odors. The origin of these gases is double (they can come from the substrate or be biologically or even chemically formed during the process) and they need the development of mitigation strategies based on relatively consolidated technologies (such as biofiltration) or new approaches, such as the use of materials as biochar. However, there is still a lack of reliable and full-scale data from composting emissions to have consistent mitigation strategies.
This entry is adapted from the peer-reviewed paper 10.3390/pr9101844