- Q: Why should I support composting?
A: Composting at its best is a sustainable method of waste disposal which utilises the natural organic processes of aerobic decomposition to achieve the recycling of nutrients and trace elements from organic wastes.
- Q: Will commercial composting in my neighbourhood cause odours?
A: Composting activities when run in a suitable purpose built facility should cause a negligable odour impact.
- Q: I have heard of composting plants which in the past have caused a substantial nuisance and have even been closed. Is this correct?
A: Clearly, during initial stages of composting there is significant potential for odours to be generated. For example, some large scale windrow schemes have caused such problems, and have been closed. However, odour nuisance can be avoided with careful design, although prevention may require additional initial investment.
- Q: What is a windrow?
A: A windrow is the term used for composting in the open, whereby the compost is allowed to stand until the digestion process reaches the required stage, and the material is normally turned regularly.
- Q: What is the definition of compost?
A: Compost is the product resulting from the controlled biological decomposition of organic material, occurring under aerobic conditions, that has been sanitised through the generation of heat and stabilised to the point that it is appropriate for its particular application.
- Q: What is the difference between aerobic composting and anaerobic digestion?
A: "Aerobic" simply means in the presence of air, and may entail regular turning of larger piles or windrows to maintain the free flow of air. "Anaerobic" means without air, and anaerobic digestion (AD) entails the use of special vessels to maintain airless conditions.
- Q: What is biodegradable waste?
A: Biodegradable waste is waste which will degrade either in the presence of air or without air. It comprises waste such as card, paper, food and green waste and natural textiles. As this waste degrades in landfill it produces methane which is a powerful greenhouse gas. methane which is a powerful greenhouse gas.
- Q: What are the UK waste reduction targets?
A: Click here to see the "targets" page on this web site.
- Q: What proportion of municipal solid waste is organic/biodegradable material (eg vegetable matter (including garden waste), paper, food scraps, garden waste, and some textiles)?
A: Compostible materials, account for 20% to 30% of most household waste streams, where no separation takes place at source.
- Q: What is commercial composting?
A: By describing our web site as "commercial" composting we are distinguishing our site from the very many "home" composting sites which, for example, among other things, most often sell plastic composting systems.
The big hope is that compost markets can be expanded rapidly to enable the composting organisations which are taking organic wastes which must now be diverted away from the landfills to be commercial (ie sell their product and make money!) rather than depend almost wholly on government subsidies.
There are two driving forces behind "commercial" composting at present in the UK. The first is obviously to compost for the environmental benefit in reduced use of chemical fertilisers, and to slow down the rate at which landfills are filled up.
The second driving force is the European Union Landfill Directive, and if the UK, (in common with all the other EE Countries) fails to achieve targets for the reduction in the total quantity of organic material being placed in landfills, we will as a nation be fined by the EU.
- Q: What are the main steps in commercial composting?
- A: These are usually:-
- Shredder chips material: in the case of garden wastes, or if there is no source separation a pre-sorting stage selects the compostible materials from the waste stream;
- Composting stage: in open or closed vessels for 3-4 weeks;
- Maturation: to stabilise the compost, for several months;
- Post-processing: to remove solid contaminants, and to screen the product before sale or use.
