With organic waste levels increasing in line with a growing population, organic waste facilities have their work cut out to meet capacity.
Investment in in-vessel composting facilities, including containers, silos, agitated bays and enclosed halls has soared. Still, an often unspoken aspect of organic waste treatment – odour control – has seen soaring investment too.
Organic waste facilities produce various odorous gases because of the decomposition of different types of organic waste, emitting organic gases, aromatics, nitrogenous compounds and S-compounds like hydrogen sulphide (H2S).
Due to increasing volumes of organic waste, organic treatment facilities need increasingly large and efficient odour management systems, which can be as simple as passive filters or tube vents or as complex as multi-stage treatments.
Here’s a run-down of the main technologies used in organic waste facilities:
The most prevalent and effective odour control technology for organic waste facilities is biofiltration. Biofiltration systems are low-maintenance, use no chemicals, and produce no sludge, helping to reduce waste further.
In a biofiltration system, microorganisms feed on odorous compounds in air gas streams, assimilating them into the biomass. The microbial action can degrade biodegradable contaminants into CO2, H2O, mineral salts and organic compounds (food for the biomass).
OSIL biofiltration systems use LavaRok®, a modern substitute for woodchip and shells in biofiltration units. LavaRok® is made from pumice stone, which has a 25-year lifespan and promotes a healthy, diverse ecosystem.
Biofiltration systems are used as a primary treatment technology in organic waste facilities because they effectively treat all organic odours.
OdaCompact® (two-stage treatment)
OdaCompact® is a two-stage treatment tower combining biofiltration with CuCarb® Dry Media filters, such as activated carbon filters.
We specify OdaCompact® when a space-saving design is required, and a two-stage treatment is desirable. Each dry media filter is tailored to treat specified odours, with H2S, organic sulphides, ammonia, amines, and VOCs treatable.
Dry media is a good match for biofiltration because it polishes the process, capturing odours the biomass can’t, perhaps because of capacity.
Dry media filters work through adsorption, a process that sees atoms, ions and molecules from targeted gases adhere to the media, producing scrubbed air. The filter media need replacing when spent to maintain the efficiency of the system.
Passive filters or tube vent filters
Passive / tube vent filters are the simplest odour control technology, typically specified for containers, holding tanks and pump sumps under positive pressure to adsorb gases.
A passive filter is designed into a system called a passive odour control unit , a self-contained system. .
Passives are effective at removing hydrogen sulphide and other S-compounds from air gas streams. They use activated carbon in granular or pellet form, which is easily replaced using the refillable filter mounted at the top of the unit.
Passive filters are mostly used in wastewater treatment works, however, organic waste facilities also use them to treat gases from containers, silos and agitated bays. Passives are mostly used as a final polishing stage for treated gases.
Find out more
We can recommend, size and specify the right odour control solutions for your organic waste facilities. Contact us today for a chat.