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When biodegradable material such as food waste is sent to landfill it rots without air to form methane which is an extremely potent greenhouse gas, more potent than carbon dioxide.
It also forms leachate which is a liquid effluent that needs to be treated. If leachate enters water courses it is highly poisonous to aquatic life.
To get round this, food waste is composted by a process called In-Vessel Composting (IVC).
Food waste is shredded, mixed with garden waste and placed in large sheds (vessels).
The waste is then composted in the vessel for seven days during which air is pumped through it to keep the composting process aerated. Temperature probes ensure that there is sufficient heat to kill any dangerous bacteria. 60oC must be achieved for two consecutive days. The waste is then transferred to a seperate vessel and composted for a further 7 days where it must again reach 60oC for two continuous days. The waste is then transferred to the matuartion pad for a further 6-10 weeks in windrows (heaps). It is then screened for use as a compost product.
No chemicals are added to the process, and the heat is produced entirely by the composting process itself.
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