“I would say that it would probably be better for councils to collect green waste every week when it is hot, as a measure to cut down on odours,” said Mr Dampney, who is also the founder of Dorset firm Eco Composting.
”It would probably be better for councils to collect green waste every week when it is hot. “
– Trelawney Dampney, the Composting Association
The comments came after Grantham-based company Mid-UK had its composting operations shut down earlier this week because of complaints of odours (see letsrecycle.com story).
The director of Mid-UK, Chris Mountain, said that “green waste sitting on the kerbside for two weeks reaching temperatures of 80 degrees centigrade” was very likely to generate odours.
Measures
Composters can use a range of measures to reduce odours, some of which Mr Mountain is now putting in place at his site.
Mr Dampney said that odours could arise as green waste is released from enclosure on a collection vehicle onto a compost site, but that this could be reduced by using misters or odour abatement systems as the green waste is being released.
“It would be better particularly in the hotter weather to have wet green waste from the kerbside collected weekly to reduce odours, but there are measures that can reduce this,” he said.
Stephen Wise-Merry, SITA UK's composting manager agreed that odours were associated with the releasing of wet green waste onto a site in hot weather, and said the key was to ensure this material is incorporated into the composting process early.
“At SITA sites the material is usually put into the composting process within 72 hours,” he said.
Mid-UK
Mr Mountain of Mid-UK said that he hoped his composting site would be up and running in a week and that he aimed to shred all material coming in and start composting it within 48 hours of its arrival on-site.
He also said he was strongly considering building a shed to received green waste from collection vehicles to contain smells after odour abatement systems had failed to combat the problem.
But composting experts said that such a measure would be expensive and shouldn’t be necessary with careful planning.
Mr Wise-Merry said that sites should not take on more material than they can comfortably handle and should shred wetter material from the kerbside, rather than more woody material from CA, sites as quickly as possible.
Cover
Another expert, Ray Williams, waste management specialist at ADAS research and consultancy, said that going under cover could be a good option.
“Obviously there's less risk of odour if the whole process is enclosed but it can be grossly expensive,” he said.
| Related links: |
Mr Williams, whose company devises odour management plans for composters, said there is much that can be done to reduce odours. “The wind direction is important to consider. Composters need to be mindful about the direction and strength of the wind on the days they are mixing and turning material.
“If the wind is heading towards nearby housing for example, it's a good idea to leave the mixing for a while. There must of course still be sufficient mixing and turning to aerate the material throughout the composting process.”
Register for free to comment