How to Select the Best Air Blower for Your Need

The world's industries that require low-pressure blowers and compressors include wastewater treatment, fish farming, food and beverage, cement factories, and oil and gas. Given that each application has distinct needs and requirements, it stands to reason that consumers would prioritize various purchasing aspects when determining which sort of low pressure air blowers will best meet their needs!

What factors should I consider while selecting an air blower?

A comprehensive review of the installation and application is critical for picking the proper technology, and one or more factors will likely take precedence over others. For example, a smaller location for the blower may necessitate selecting a technology with a smaller footprint and lower noise levels, but an application requiring lower energy costs may be better suited for an energy-efficient technology with a greater initial cost. The following are important variables to consider:

Flow and pressure

A properly sized blower installation will aid in the achievement of a more energy-efficient operation. For example, if a compressor with pressure reducers is used to create low-pressure air, replacing the compressor with an air blower capable of delivering less than 3 bar(g) air will result in considerable savings. Every 1 bar(g) of air compressed over the actual requirement wastes 7% of the energy.

Conditions for use

Blower selection is influenced by site circumstances.For example, a dusty environment or hot humid site for a blower installation may necessitate the selection of a technology that provides a dependable positive displacement screw, lobe blower, or multistage centrifugal to provide a dependable source of low-pressure air that is less sensitive to dust or high ambient temperatures.

The application requirement of reduced energy costs, on the other hand, may be better addressed by a more energy-efficient technology with a greater capital cost.

Initial capital outlay against highest ROI / TCO

The cheapest option to buy does not always imply the lowest operational expenses.To maximize ROI, it is therefore recommended not only to consider investment expenditures during the design phase, but also to analyze necessary spending during the full life cycle of the equipment.

Total cost of ownership (TCO) and Return on Investment (ROI) are crucial decision factors during blower selection to guarantee both investment and operating expenses are maximized, since energy consumes over 80% of a blower's lifespan cost.

The video below discusses total cost of ownership in the wastewater treatment application, where Atlas Copco was able to fulfill our end-users' objective of optimum TCO while limiting the environmental effect of continuous blower operation:

Noise levels in the workplace

Intelligent baffle and canopy design, which enables lowered sound levels down to 70dB(a) for an enhanced working environment, is a characteristic of the current generation of low-pressure blowers. As a result, installation expenses are decreased because noise-insulated rooms and doors are not required.

Service and lifetime support

When it comes to routine maintenance and service support, some older blower technologies may require units to be serviced, repaired or re-furbished offsite. Advanced design developments in the latest oil-free, low-pressure blowers now sees the inclusion of low maintenance components, extended on-site service intervals, each blower technology need to have routine services and checkups, however each technology design and mechanism differs on the number of consumables and service periods and the benefits of lifetime customer support plans.

Comparative performances

It pays to check the vital statistics. As an example, the tri-lobe rotors incorporated into the latest generation of low-noise, low-vibration, low-pulsation blowers can sweep nearly six times the volume of air in a single revolution compared to their belt-driven, twin-lobe predecessors. On average, this older technology experiences 5% - 7% more transmission losses.  

An important advantage of the direct-drive, oil-free, rotary screw blowers is wide turndown, especially on models with integrated inverter drives. This allows the units to match the airflows to the daily and seasonal variations in the effluent inflow, resulting in additional energy savings. In order to cope with fluctuations in air demand, screw blower technology can operate from 25% to 100% capacity with very little change in specific power requirement.

The variety of air blower technologies

There are multiple compression technologies that are used for generating low pressure air. The three main technologies that are popular today are lobe, screw and centrifugal; and within the centrifugal technology there is multistage, high speed turbo or integrally geared centrifugal blowers. So, this takes us to five types of blower technologies that are used extensively within the low-pressure market.

Each technology has its own space like lobe typically is the best when it comes to pressure below 0.5 barg and flow less than 2,000 m3/hr, while screw works better at higher pressure and flow between 1,000-7,000 m3/hr and then centrifugal technology takes over for larger volumes.

However, the decision on a compression technology is steered by energy efficiency which is also linked to the specific application of low-pressure air.

Lobe vs Screw

A lobe blower (also called a Roots blower) is a traditional and reliable technology that offers low initial capital cost. Screw blowers, in comparison, offer greater reliability, high turn down, and superior energy efficiency for a greater ROI.

Multistage vs Turbo

Multistage blowers are best for specialist applications and offer an industry standard performance for very large flow requirements. Turbo or turbo-multistage blowers, however, are a combined technology configuration that provide reliable, market leading performance for varying air demands for the lowest lifecycle cost and ultimate energy efficiency.

Combining technologies

Different manufacturers recommend a specific technology depending on their expertise in that technology however if a user keeps the selection limited to one technology it could result in missing out on improving energy efficiency of the installation.

Atlas Copco is one of the very few global manufacturer that has expertise in all the technologies and could offer the most suitable and reliable system that can deliver the best energy efficiency of a low pressure compressed air installation by combining different compression technologies available to handle the compressed air demand.

Whatever your low-pressure needs, the ultimate aim is for a blower system that provides total reliability, guaranteed continuity of process operations, and combines optimum performance with protection of the process, the environment and operational energy costs. We recommend reaching out to an established low-pressure expert who understands your application’s unique needs and provide you with guidance about the best-fitting technologies. Contact our expert today to get more product information!