Composting and the Development of Commercial Composting Processes
By Steve Last
This article describes the progress seen in many countries where large scale composting processes are being introduced from garden waste to food waste, from windrowing to complete odour free in-vessel systems.
Throughout Europe (EU) all nations are committed to the processing of as much of our organic waste as possible. It is a priority if we are to reach Government recycling targets which are designed to ensure we comply with the EU's Landfill Directive, and divert our wastes away from landfilling.
The answer to this is composting, which is the natural way to bring left-over organic material back into the nutrient cycle. Composting can also be the first stage toward more sophisticated waste processing technologies such as Anaerobic Digestion, and take us toward the “carbon economy” which many see as the intermediate step before the “hydrogen economy”. 
The demand for hydrogen and biofuel generally will lead us toward Anaerobic Digestion and methane generation for power. Methane can then be processed further into renewable fuels such as bio-methanol and biodiesel - away from dependency on oil as our fuel source - and toward a marvelous new freedom from fossil fuels.
We are now in very many countries embarking on the next step toward the carbon economy by building on our success with composting household green waste by beginning to compost commercial waste, and food wastes too. Food wastes are great feedstocks for anaerobic digestion.
Composting is the answer for many communities now to keep awkward and potentially hazardous materials out of landfill. But it has other advantages; it reduces landfill volumes and also removes a proportion of the organic matter which is the cause of landfill leachate, methane and odour producing gases and smells.
Modern commercial composting processes are run under the appropriate regulations for the waste involved, to ensure the safety both of the workers involved and of the final product.
Using modern composting methodology garden waste materials, like grass cuttings, bush pruning, twigs and branches, can be broken down outdoors in the traditional way of composting which is known as "windrowing". A compost pile is built – also called an open windrow – which just needs regular turning over a period of time to allow the bacteria to work.
For more difficult materials and to be sure that all odours can be strictly controlled and to achieve the results in a shorter time, the most modern facilities are fully enclosed, computer-controlled chemical "in-vessel" processing plants. 
They pump measured and scientifically controlled amounts of air and moisture through the organic waste and the temperature is carefully monitored, and the results are continuously recorded.
Kitchen and garden waste makes excellent compost – this is nature’s way to recycle organic matter, after all.
Many industrial and commercial businesses also produce organic waste materials from such activities as food processing and retailing. Often these commercial waste products can be similarly composted to mature into a compost product of value to farmers and landscapers.
The value of compost comes from its fertilising capability, and also from spin off benefits such as improved soil structure which improves moisture retention and avoiding the loss of this material into landfill.
All United Kingdom local authorities are now composting green (garden) waste, and some are more advanced than others. Many tens of thousands of tons of superbly high quality, rich compost is now being produced every year. The compost is sold in bags to local residents and in bulk to landscapers and commercial growers.
Waste organic material from industry and commercial sources can carry contagious organisms (including viruses) so great care has to be taken not to spread these around through the composting process. Lessons learned from the past and most notably during the UK's foot and mouth epidemic three years ago has lead to new regulations. For example, waste meat products are managed under the Animal ByProducts Regulations (ABPR).
Nowadays many local authorities, and their private sector waste disposal contractors, have had their composting processes approved by the UK's Soil Association and Compost Association, and have been awarded ISO 9001 (Quality Assurance) and 14001 (Environment) compliance certificates.
So, next time you have some waste food or grass clippings, don't throw them in the bin with your other waste. Do keep them separate and either compost these wastes in your garden yourself, or send them to the recycling facility - and join in the environmental recycling movement.
Visit Commercial Composting information and free technical reports for download.
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