WOULD YOU PEN & INK IT?
Residents of Stovolds Hill and tenants at Dunsfold Park are up in arms over the nasty stink emanating from a bio-digester situated in a field adjacent to the Industrial Park.
“It’s like living next door to a rotting compost heap,” raged one irate resident. “I’ve tried complaining to the biodigester’s manager but he refuses to accept it’s anything to do with his plant. He blames local farmers, claiming they must be muck-spreading! I’ve told him that’s ridiculous. We never experienced any odour problems on Stovolds Hill until the bio-digester was built.”
Residents are allegedly furious because they were assured when the plant’s operator applied for planning consent that there was no need whatsoever to worry about unpleasant odours. Still, now it’s operating, they plague them, sometimes daily. As it would seem, are other residents who have the misfortune to live close to another plant operated by DBE Energy.
But not a word from Protect Our Waverley (POW) whose leaders Bob Lies and Chris Britton, (who lives nearby and who we understand has morphed into an Alfold Parish Councillor no less). Wonder why the deafening silence from POW?
That was the bluster …
Now for the science (courtesy of Google, so if we’ve got it wrong, blame them!):
According to our researcher, except where anaerobic digesters are built in isolated locations away from towns and villages, additional, active odour control measures will always be necessary to prevent nuisance to the local communities.
Is this, maybe, the cause of the problem? Sitting at the bottom of Stovolds Hill, adjacent to a business park, did the Local Authority and DBE think the plant was sufficiently isolated not to warrant these additional measures?
Back to the science:
For active odour control, it’s necessary to set up a network of atomizing nozzles around the main odour-producing parts of the site, which are fed under pressure with a dilute, aqueous solution of an effective odour control chemical formulation. The smaller the atomized droplet size, the larger the surface area to droplet volume, therefore the more effective the droplets are at capturing / neutralizing odours.
High-pressure (60 to 70 bar) atomizing systems are more effective than low-pressure atomizing systems (5 to 15 bar) since these high-pressure systems produce smaller droplets, typically 10 to 15 microns in diameter, than the lower-pressure systems, which produce droplets typically 20 to 50 microns in diameter. It’s often advantageous and can improve odour control with fewer nozzles by combining the nozzles with fed-driven venturis, ensuring an effective spread of the droplets and mixing with air. The layout of the nozzles and venturis across a site is very important to ensure effective control of odours and appropriate consideration must be taken of the proximity of local communities, wind direction, potential amount/strength of release of odorous gases from particular items of digester plant, etc.
The selection of odour control chemicals is also crucial, as many odour control products on the market only contain perfumes and have some surfactants added. This product merely masks bad odours and does not neutralize them, leaving the odour still present. A suitable chemical formulation for odour control will be highly concentrated and will contain a number of active ingredients that specifically react with and neutralize the problematic odours — ammonia, hydrogen sulfide, etc. — to ensure that it’s both effective and cost-efficient.
Depending upon the anaerobic digester feedstock and digestate handling procedures, aerosols of feedstock/digestate containing pathogenic bacteria/fungi might be released into the air and could pose a hazard to plant operators and people living nearby. In the case of a risk that such aerosols might be produced at an anaerobic digester plant, this risk can be mitigated by using an odour control product that contains a synergistic blend of cationic biocides, which will kill most gram-positive and gram-negative bacteria and fungi upon contact.
To minimize odour control operational costs, a super concentrate odour control product should be capable of being diluted to at least 1 part in 500 parts of clean water, rather than most conventional odour control products that are used diluted at 1 part in 100 parts or 200 parts of water.
In conclusion, a combination of treating gases produced by the process and active odour control will ensure that the population in nearby towns and villages are not troubled by the release of unpleasant and obnoxious odours emanating from anaerobic digester plants.
So, the question is? Is DBE Energy, the owner/operator of the plant doing everything it should be doing to protect the local community from the stink their operation is causing or is it cutting costs/corners at the expense of local residents and businesses on the Park impacted by its so-called efforts to ‘tackle climate change from within our local community?
To encourage the plant’s owners/operators to take the odour issues seriously, local residents are urging everyone who is affected by the smell to complain on every occasion they smell the noxious concoction being brewed at the plant by contacting the plant manager here:
and also by contacting Surrey County Council’s Enforcement Officers to alert them to the problem as it is a condition of the plant’s planning permission that any and all escaping odours are thoroughly investigated: Paul Warner – Senior Enforcement Officer
Telephone: 020 8541 9897