Cause and Effect

Landfills aren’t the only locations where dust and odor are problematic. Like other industrial-scale waste processing facilities, materials recovery facilities (MRFs) and transfer stations experience recurrent challenges to contain both.

“Managers are faced with handling the complex issue of dust and odor to remain in operation, protect their workers, and maintain a positive reputation in the community,” says Marc Byers, founder and president of Byers Scientific & Mfg.

Maintaining a positive reputation in the community is complicated by public scrutiny, which often results in increased regulation that brings with it additional risk, operational inefficiency, and cost. “It is critical for MRF and transfer station managers to take a proactive approach to mitigate industrial odors and emissions to ensure a stable future,” Byers believes.

Beyond critical, it has become a legal requirement in some areas. In 2020, New Jersey Governor Phil Murphy (D) signed landmark environmental justice legislation into law. It spotlights emissions concerns from MRF and transfer stations, among other types of facilities. The law (S232) imposes new requirements for industrial facilities to conduct an environmental impact assessment to obtain or renew an operating permit. Its purpose is to identify “overburdened communities” and facilities that are major sources of air pollution, as defined under the Clean Air Act—specifically, incinerators, sludge processing facilities, large sewage treatment plants, transfer stations, recycling facilities, and landfills. The New Jersey Department of Environmental Protection determines if there are disproportionate, cumulative environmental impacts.

While this particular law’s requirements are part of the most far-reaching environmental justice legislation in the country, Byers says this level of regulatory focus on industrial waste processing facilities is not going away. Although the law does not explicitly address dust and odor, he believes it’s clear that solid waste facilities will continue to face elevated scrutiny.

Consequences of Not Addressing the Problem

Odor and dust in the facility compromise worker safety and air quality, potentially resulting in insurance claims if they are determined to cause injuries. Fugitive odor and dust can lead to complaints, which can result in a notice of violation, evaluation by the local regulatory agency, fines, and a community organized against the facility.

If odor problems are not addressed, several issues can arise, such as detrimental effects to the working environment, efficiency, and job satisfaction, reports Bill Scott, sales manager, Ecolo Odor Control Technologies Inc. “Also, the surrounding neighborhood plays a role here, as unaddressed odor issues can result in complaints and long-term problems.”

Simply put, it’s a health and safety issue. Derk Maat, owner, SciCorp International, mentions the necessity of ventilating the processing areas not only to meet national standards but because "it's bad for workers if there's no odor control."

Because MRF and transfer station managers face several issues related to odor, including human health and the environment, Clara Cheng, head of R&D, Ecolo Odor Control Technologies Inc., says they must develop safety procedures to minimize odor impacts on the quality of work and the environment.

“Dirty” MRFs receive a stream of unsorted solid waste containing anything from organic waste to paper, plastics, metals, glass, fabrics, and even large appliances, giving rise to the potential for more issues of malodors. In addition, MRFs must rely on manual labor to sort irregular objects that machinery cannot handle. Therefore, they require odor control to provide safe working conditions for their workers and to function well, especially when in close proximity to residential neighborhoods and businesses.

“Ultimately,” Byers reflects, “unacceptable emissions of dust and odor by MRF and solid waste transfer station facilities cannot only impact the operator’s bottom line but, even worse, may affect their ability to operate at all.”

In addition to “a bad public reputation that is nearly impossible to remedy,” excessive complaints from the community against a local waste facility can lead to fines and litigation expenses, Byers says. “Social media shaming of municipal waste businesses can cause brand destruction.” Worse, local enforcement officers are obliged to investigate nuisance odor complaints, which takes time away from valuable production activities. Thorough investigations can even shut down daily operations.

Furthermore, certain odorous compounds and particulate matter are known to be harmful to air quality, which can cause an operation to fall out of compliance according to local, state, or federal air quality regulations. This level of non-compliance comes with stringent investigations and follow-up procedures during which the operation will likely not be allowed to operate.

Prevention is the Best Cure

Nevzat Turan, principal, Weaver Consultants Group, believes that prevention should come before control. That begins with designing, constructing, and operating a facility with dust and odor prevention in mind.

Facility design and proximity to neighbors both impact odor issues. Keeping facilities clean and well-ventilated can help reduce complaints. “Good housekeeping and operations that consider odor prevention are key for the solution and should be a priority before odor control measures.”

Once preventive measures are implemented, then odor control measures should be developed. Not only is facility design critical to a solution, but so too is the type of material a facility accepts. For example, C&D recycling operations mostly deal with dust, says Turan. Solid transfer stations primarily deal with waste odors and odors from operation surfaces such as tipping floors, loading tunnels, and vehicle maneuver areas. Left untreated, he says, it “becomes a compliance issue, either as a visual emission or nuisance odors detected outside of the property boundary.”

Because transfer stations and MRFs are different, it’s important to engineer the solution by identifying the problem odors, taking into consideration the waste characteristics and analytical testing.

Products to mitigate odors include non-fragrance deodorizers deployed by aqueous or non-aqueous applications. “Aqueous methods still use significantly less water than traditional misters and are suggested for operations that deal with appreciable dust problems along with odor issues,” Turan advises. Non-aqueous technology focuses mainly on odor problems. For instance, Weaver Companies customizes deodorizer chemicals for both methods through analytical testing along with bench-scale studies using actual odorous air samples.

Different Problems Demand Different Solutions

Dust and odor should be looked at as two separate problems, states Jesse Levin, vice president of sales, Atmos Technologies. With dust, he advises focusing on the source—using a high-pressure, water-based misting system to mitigate dust before it becomes fugitive. “A high-pressure atomizing nozzle knocks down dust,” he says, emphasizing that controlling dust is an OSHA issue for worker safety.

Multi-zone systems can be established at MRFs to focus on different areas, such as the sort line, shakers, the tipping floor, load-out area, and entrances/exits as the “last line of defense.” It’s necessary to calculate water flow rates for each zone and choose a system capable of handling changing rates.

When odor is the issue, Levin advises against putting dispersion nozzles on equipment and says to put the system where they’re most needed: load-out, the tipping floor, and entrances/exits. “Identify the problematic areas.”

Levin believes it’s important to have a high-quality engineered system to address changing needs throughout the day. “If all the nozzles come on, you’re wasting water, chemicals, and energy. You want to minimize water consumption and use the least amount necessary to be effective.” On the other hand, he realizes that “some loads are smelly” and need extra treatment. It’s possible to increase the odor control neutralizer on Atmos Technologies systems. An additional benefit is remote operation and the ability to “change on the fly, from anywhere.”

Misting and More

SciCorp International offers a non-hazardous, invisible, easy-to-apply, plant-based product that instantly changes odor molecules into a non-odorized form by stimulating specific aerobes and anaerobes while inhibiting sulfur-reducing bacteria and ammonia-forming bacteria and enzymes. The result is significantly reduced odor while the bacterial breakdown of organic waste continues at an accelerated rate.

At transfer stations, Derk Maat, owner, recommends a diluted solution of Biologic SR2 be distributed as a mist or fog on a timer to entrap dust particles, which settle and fall. “It eliminates dust in the nose,” he mentions, and because it’s atomized, he says the “workers won’t even feel it.”

It can be used on the working face at landfills to stop bacteria from producing odor, and at wastewater plants, dairy lagoons, and pulp and paper mills to reduce sludge. It can even be used to clean garbage trucks. “We’re thinking about putting it on the back of residential garbage trucks,” Maat reveals, where the push of a button could release a burst of mist or vapor to neutralize odors.

The main ingredients in this biodegradable micronutrient solution are amino acids, vitamins, plant-based organic, and trace minerals. The primary benefit of the solution is that it eliminates the formation of odors at the source: the biological reactions responsible for organic waste degradation.

Additional benefits of using the proprietary blend of organic micronutrients include:

• Eliminating 90% of capital investment for odor control using chemical, biofilter, ozonation units, and/or carbon units to contain, control, and treat odors
• Eliminating 90% of the energy needed for conventional odor control strategies
• Near-zero carbon footprint
• Speeding up composting

Remedies to Address Odor Problems With or Without Dust

Misting systems tackle dust and odor at MRFs and transfer stations, but Byers says odors can persist in the absence of dust. For that situation, he says filtration, or carbon scrubbing, is an efficient and sustainable alternative to a water-based system.

For those who want to leverage molecular filtration for odor control and still retain the ability to use atomization for dust suppression, Byers Scientific offers a high-pressure atomization system with intermittent fogging of an odor neutralizer formulated for solid waste. “Because every Byers Scientific product leaves the shop with its own website on our Cloud-based Bolt-On SCADA platform, we can leverage this functionality to automate and toggle between the operations of these separate but combined technologies: e.g., scrubbers on, misting off, and vice versa.”

Using IIoT technology reduces manpower and permits 24/7 real-time monitoring and reporting so facility managers can prove compliance with odor abatement plans to the regulatory agencies.

Target Solutions

Ecolo has developed odor neutralizers that counteract malodors rather than merely masking them, Scott says. He underscores the importance of choosing a solution that targets the specific malodors at a facility, as well as the appropriate dispensing system that matches the physical and operational parameters of the facility.

Solutions that are effective at MRFs include a combination of BioStreme and AirSolution, the latter of which targets mercaptans, amines, and sulfide-related odors resulting from the breakdown of green wastes, grease, and proteins, Cheng explains. This makes it a popular choice for MRFs, transfer stations, landfills, and composting operations.

Maintenance

Providing a system is one thing, Levin says, but what if it breaks down? “Some permits require the system to be operational.” To keep customers up and running—and compliant—Atmos Technologies has a nationwide service team that can get to the customer in 24 hours.

In addition to emergency service, their service agreements cover routine maintenance: motor, pump, water filtration; clogged nozzles, controls for multi-zone systems. “Maintaining equipment is a key component for MRFs,” Levin states. Their recently added ability to remotely diagnose and troubleshoot minimizes downtime and increases efficiency.

Implementation of a dust and odor control plan won’t be successful without ongoing maintenance. All equipment should receive routine maintenance. “Nozzle maintenance and prevention of clogging, partly because nozzles traditionally are not designed for these types of environments, is still one of the main challenges,” Turan identifies.

Ecolo approaches maintenance from an equipment standpoint: providing systems like the ACU.25 and AMC that are easy to maintain and provide long life and reliability. Scott mentions the company’s troubleshooting guides and videos that assist customers with routine maintenance. “Problems are easy to keep in check with routine monitoring and simple maintenance. For example, if a system does not appear to be spraying or spraying properly, one can review the troubleshooting guide to see the common causes and solutions.”

Doing Business

Whatever solutions a facility manager chooses, dust and odor control is not auxiliary to business, Turan sums up. Regulatory, health, and productivity needs drive the industry to continue developing more effective and efficient products and processes to keep dust and odor under control.