Equipment: Shredders
Community projects in Devon were initially supplied with 8 HP shredder/chippers. One of the problems with community scale composting is that it is filling a vast gap between home scale composting needing few if any, resources, and large, municipal scale operations which require a £100,000 machine to shred materials, a £100,000 machine to turn the windrows and another £100,000 machine to sieve the end product.
Community projects themselves can vary enormously in scale too depending on the size of the community and the scope of the project. Projects like WyeCycle in Kent and Uffculme in Devon have developed into small businesses collecting tonnes of materials every week and paying for the labour involved out of the recycling credits accrued. A big problem is the scaling of machinery to the scope of the project. A £2,000 8 HP machine needs to be regularly used to make it's purchase worthwhile. On the other hand using a relatively small machine like this to process large amounts of materials is extremely time consuming, noisy and not conducive to a pleasant working atmosphere. With the urgent need to remove as much of the organic fraction as possible from landfill sites, it makes sense for Councils to provide a variety of options including a mobile shredder service, to those people who wish to compost their own communities materials.
The benefits of having a much larger machine with an operator.
• Groups do not have to be trained in the use of a shredder.
• Volunteers can devote their time to making compost.
• Less noise. The machine is only running for a relatively short time as it processes materials far more quickly and efficiently.
• The group does not have to insure the machine.
• They don't have to find the costs of running the machine: fuel; spare parts; repairs etc.,
• They don't have to build a shed to put it in!
• Much larger amounts to compost can be contemplated with the removal of this most demanding task,
• Potential shredder accidents and costly claims and settlements will be avoided.
The disadvantages of a larger machine.
• You have to have sufficiently large amounts of' materials to merit having a larger machine visit.
• This means that materials may have to be stockpiled for quite a while. This in turn means that:
a) the site must be large enough to accommodate the stuff, and
b) the materials must be separated and stacked, so that any putrescible items are removed, that might otherwise clog up the machine.
• This also means that instead of branches being chipped green, as they ideally should be, they are likely to be very dry and hard making them less suitable to being made into compost, or at least not as quickly. The way materials are stockpiled on site will have to be thought through carefully. However with the increase in the number of projects around the County it means that the shredder can often visit two or more projects in a day, and therefore less material has to be stockpiled.
• You must have good level access and turning room on site.
• Last but by no means least - shredder budgets are not infinite!
