Are some Air Filtration Systems more environmentally friendly than Others?

Choosing an air filtration system that actually improves the environment can be challenging because there are hundreds of options available. Factors such as contaminant type, airflow requirements, filtration efficiency, maintenance needs, operating cost, and environmental impact all play a role in selecting the best solution.

Environmental impact has become an increasingly important consideration for many manufacturers. While every air filtration system can improve the environment inside a facility, some technologies have a larger impact on waste, energy consumption, and overall sustainability.

For companies focused on goals such as net zero, reduced waste, or improved sustainability, the environmental impact of an industrial air filtration system should be considered during the selection process.

Waste Sent to Landfills

One of the most obvious environmental impacts of many air filtration systems is the disposal of used filters. Once disposable filters reach the end of their service life, they are typically discarded.

Disposing of dirty filters can create additional challenges because used filters are usually considered hazardous waste unless they have been tested and classified appropriately.

Media Filtration

Media filtration systems rely on disposable filter elements, these can absorb gallons of contaminant, which means they naturally create more waste compared to reusable electrostatic  technologies. Selecting the correct filter for the application is important to maximize filter life, reduce waste, and control operating costs.

Centrifugal Filtration

Centrifugal filtration systems use a rotating drum to spin the air and separate and collect a large percentage of contaminants. This can reduce the amount of waste compared to traditional disposable media filters.

However, many centrifugal or spinner-type filtration systems still use disposable pads inside the drum to improve collection efficiency. Some applications may also require after-filters to achieve the desired level of filtration. They also use about 3x the energy of electrostatic air cleaners another waste.

Electrostatic Filtration

Electrostatic air filtration systems do not use disposable filters. Instead, they use reusable aluminum collection cells and ionizers to capture airborne contaminants.

A large portion of the collected oil mist and smoke drains away from the collection cells naturally since the metal filters don’t absorb contaminants. When the cells are professionally cleaned, the remaining contaminants are removed from the aluminum plates and separated from the cleaning solution, allowing the waste material to be properly recycled or disposed of.

This reusable design significantly reduces landfill waste compared to disposable filtration systems.

Energy Consumption

Energy consumption is both an economic and environmental concern. In most filtration systems where you separate by moving air through restrictive material to remove small particles or spin the air to centrifugally remove particles a lot of resistance to the air flow occurs.  High resistance = High Energy. A higher pressure drop (air resistance) requires more energy to move the same amount of air through the system. Electrostatic air cleaners charge particles regardless of size and attract them out of the airflow to collection plates.  This method of collecting particles allows clean air to easily move through the filters while capturing the contaminant. The energy use of electrostatics is usually 1/3 or less compared to other systems. 

Uneven Airflows

Media filtration systems typically have a changing pressure drop throughout their filter life..

When filters are new, airflow resistance is relatively low. As contaminants collect on the filter media, pressure drop increases until the filter needs to be replaced.

This means the fan and motor must be sized to overcome the restriction created by loaded filters. However, unless equipped with a VFD that compensates for this, that same amount of energy is being used even when the filters are clean.

For larger media filtration systems, variable frequency drives (VFDs) can help reduce energy consumption by adjusting motor speed based on actual airflow requirements.

    Due to their design, Electrostatics maintain very balanced airflow throughout the life of their filters. They pull the contaminants out of the air flow instead of trapping them within it. 

Centrifugal Filtration

Centrifugal filtration systems can require more energy compared to other technologies because the separator drum must rotate at high speeds to separate contaminants from the airstream.

The energy required to operate the rotating components can make centrifugal filtration less efficient when compared to other filtration methods.

Electrostatic Filtration

Electrostatic filtration uses less energy per CFM than other filtration methods because the collection cells create very little airflow resistance.

Unlike media filters, which become more restrictive as they load with contaminants, electrostatic collection cells maintain a very consistent pressure drop throughout their service life.

Because airflow resistance remains consistent, electrostatic filtration systems do not require VFD adjustments to compensate for changing filter pressure drop.

Ozone Generation Concerns

Ozone generation is sometimes raised as a concern with electrostatic air filtration systems. Unlike media and centrifugal filtration, electrostatic systems use high voltage to charge and collect particles, which can create small amounts of ozone.

However, modern electrostatic air cleaners produce ozone levels that are very low. Testing of electrostatic air cleaners in controlled environments has shown ozone increases ranging from approximately 0.005 to 0.020 parts per million (PPM). Other testing has shown electronic air cleaners not exceeding 0.030 PPM above ambient ozone levels.

These levels are well below established safety standards and are often lower than naturally occurring outdoor ozone levels. Outdoor ozone concentrations can reach approximately 0.054 PPM after a thunderstorm, while still meeting healthy air quality guidelines.

Properly designed and maintained electrostatic air cleaners provide effective filtration while keeping ozone generation within acceptable limits.

Choosing an Environmentally Responsible Air Filtration System

Every filtration technology has advantages and disadvantages. Media filtration may be the right choice for some applications, while centrifugal filtration or electrostatic filtration may provide better long-term performance depending on the contaminant and operating conditions.

For many industrial applications involving oil mist and smoke, electrostatic air filtration systems provide environmental advantages by reducing disposable filter waste, lowering energy consumption, and using reusable collection components.

Bee Clean Specialties helps manufacturers evaluate, maintain, and service industrial air filtration systems, including SmogHog®, MistBuster®, Tri-Mist®, Trion®, Aerocology®, and other electrostatic air cleaners.

If you have questions about the environmental impact of your air filtration system or need help selecting the right solution for your facility, contact Bee Clean Specialties at 847-451-0844.