Waste-related odours can adversely affect local communities and cause the shut down of facilities. Over the past decade many odour control technologies have emerged: carbon filters, scrubbers, biofilters and chemical control systems that utilize enzymes, additives and neutralizers.
Neutralizers have become popular in the solid waste industry because they’re effective, inexpensive and in some cases are the only viable option. (You can’t easily put a roof over a landfill to trap odorous gases).
Neutralizing technology offers the benefit of ease of installation; automatic operation takes minimal time and incurs low capital costs. Neutralization equipment is mobile (i.e., it can be repositioned as emission sources progress or change) and doesn’t generate byproducts that require special post-treatment or disposal. In addition, neutralizing agents are CFC-free, non-toxic and are safer than chemicals typically used, for instance, in scrubbers.
The most effective neutralizing products can treat the most elusive odours. For example, Mississauga, Ontario-based Ecolo Odor Systems Worldwide, manufactures airSolution. The company has employed extensive field-testing to obtain an efficient mix of functional groups (i.e., esters, ethers, ketones, alcohols, double bonds, acids, aldehydes and amines) for various applications.
Ecolo’s system utilizes an automated liquid pump and a lightweight distribution array of specially designed nozzles to atomize its neutralizer into droplets. Atomization provides the required energy output and the resulting droplet size produces an exposed molecule surface that maximizes contact between essential oils and malodorous gases.
At transfer stations the nozzles are installed in a grid formation high over the tipping floor, loading area, scales and processing areas. At landfills the installation varies; nozzles are installed in a perimeter type arrangement (stationary or portable) and the system is placed at the working face along the sides that are adjacent to residential areas (and at areas of high-odour concentration).
After complaints from neighbors and fines by the environment ministry, a transfer station in southern Ontario decided to install the Ecolo system. For immediate relief, a simple fogger was used to spray the neutralizing solution. A pump system with 24 nozzles was installed later.
The height of the transfer station ceiling (50 feet) posed a special challenge. To provide easy access to the spray nozzles a special pulley system was installed. Each line has a winch at either end of the building affixed to a cable that may be used to raise or lower the nozzles as necessary.
A landfill and compost site in central Ontario also utilizes the odour control system. A portable “EP-60” with 10 nozzles mounted on poles is used in conjunction with a stationary system placed around the work face that receives waste materials. The site also adapted a system for its windrow turner and for general use with a wide path sprayer.
The systems have been in place for five years and have effectively eliminated odour problems and community complaints.
Written by Paul Chapple, environmental manager with Ecolo Odor Systems Worldwide, based in Mississauga, Ontario.