Breeze sells sea shells
Specialist in odour control and VOC abatement, Bord na Mona, has launched a new technology that enables companies to meet their environmental obligations with regard to keeping odours and solvent emissions from polluting the air. The technology uses natural sustainable resources to accomplish this and one of its key components is sea shells.The technology has been installed at bpi.industrial Ardeer, part of British Polythene Industries. bpi produces polythene products, and its product range utilises complex printing processes to produce high quality images on its customers' polythene packaging.
The sea shells are stacked in a tank with a perforated base. This allows air from the printing presses to be passed up through the shells. The sea shells are then inoculated with a starter culture of naturally occurring, harmless bacteria to set the system into action. At the top of the tank nozzles spray water onto the shells to create a moist atmosphere for the bacteria to grow in. The water is collected and recirculated through the biofilter. Equally, the air that passes through the biofilter is sent around the system once more to be certain the VOCs have been treated. The VOC compounds are dissolved into the water and are destroyed by the bacteria on the shells.
Bord na Mona has called the process Enhanced Biofiltration (Ebf) and branded the product Monashell. Bob Maloney, the company's commercial manager, said: "Sometimes biofilters experience unforeseen conditions outside the design parameters for which the system is specified and built. This can lead to significantly reduced operational efficiency and high maintenance. So we have looked at ways to protect the microbes from such unforeseen conditions and our research found that allowing them to make their home on a bed of sea shells is the best way to accomplish this".
The micro-organisms in a biofilter do not like acid conditions. Unfortunately, sometimes as the microbes destroy the VOCs they produce acidic by-products. The sea shells are nature's buffering agent, made of calcium carbonate, so they offer the perfect natural balance for any acidic products formed. Another important consideration is ensuring the micro-organisms see their food. Air needs to be distributed evenly through the biofilter and dissolve into water evenly throughout the tank for the VOCs to be metabolised by the microbes. The sea shells are ideal as they have a large surface area for all this to happen.