Odor management is one of the biggest challenges facing landfill operators today. Read on to learn more about this unsavory issue and find out what methods and strategies landfills are employing to deal with odors.
What causes landfill odors?
Landfill odors can come from a number of different sources. The most obvious one is fresh incoming waste. However, other contributing sources include workface activities (that is, work that is occurring in and on the landfill itself), landfill gas, leachate collection and handling systems, and condensate systems. What makes life difficult for landfill managers is that they often have little or no control over some of the key variables that make waste particularly smelly, such as the age and origin of the waste or local temperatures. In addition, environmental and geographical conditions can often magnify odor problems. For instance, windy conditions can have the effect of distributing landfill odors over a much wider area. With so many factors at play, it is hardly surprising that simply identifying where the landfill odors are coming from—much less figuring out how to control them—is a highly complex task.
Why does it seem like landfill odors are a bigger problem than they used to be?
If you feel like news stories about landfill odors becoming a major nuisance for residents are more common today than they used to be, then you’re right. Historically, people were more prepared to accept and live with the reality that facilities that handle and process waste produce unpleasant smells. However, this was before an ever-growing population pushed neighborhoods closer to long-established landfills and greatly increased the volume of trash that those landfills had to deal with. As a result, today’s expectation of what constitutes an acceptable odor level has changed significantly from yesterday, and many landfill operators who do not proactively approach the question of odor management will quickly find themselves with a public relations problem—if not a lawsuit—on their hands.
How do landfill operators currently manage odors?
Despite the fact that complaints about landfill odors are often in the news, the vast majority of landfill owners and operators are working hard to find and employ solutions to control odors. At present, odor control methods and technologies can be divided into three main groups:
- Topical sprays—Topical spray systems apply special odor control neutralizing agents directly onto the odor source using a spray-bar type of apparatus. This solution is most effective for treating sludge odors, working face odors, or odors caused by specific landfill activities or events, such as those that deal with a particularly bad waste load or the removal of a cover on a particular area of a landfill.
- Portable odor control systems—This broad term encompasses any system that disperses neutralizing agents, ranging from misting systems to waterless vapor units. The idea behind portable odor control systems is that they can be used strategically to target particular areas that are causing a problem, such as small areas where a breakout has occurred or where a spot treatment is required. The areas do not need readily available power and water sources in order to do their job.
- Perimeter systems—Positioned around the edge of a landfill, perimeter systems are designed to treat potential fugitive odors: in other words, to prevent odors from escaping the landfill and entering the surrounding environment. To accomplish this, perimeter systems release an odor neutralizer into the air, where it mixes with the escaping odors. The neutralizer can be in the form of either a liquid or a gas. Likewise, the perimeter system can be a waterless vapor system or water-based atomizing system.
However, employing these technologies is only one element of a successful odor control strategy. Two other key elements are identifying the source of the odors (this is so that odors can be treated as close to the source as possible, as odor controls are less effective the farther away they are from the source) and monitoring odor levels at the facility in order to be able to make proactive changes before off-site odor levels are affected.
What new odor management methods are in development?
In recent years, a greater emphasis has been placed on finding odor treatment methods that are sustainable and that do not require the use of chemicals or other pollutants. When odor-neutralizing solutions are based on natural ingredients, it increases the health and safety of both local residents and landfill workers. The waste management technology company OMI, for example, has developed a neutralizing technology called Ecosorb, which is created from a proprietary blend of natural plant extracts. When sprayed into the air, Ecosorb has been designed to form droplets that attract, absorb, and destroy airborne organic and inorganic odor molecules without causing any adverse side effects to people or the environment.