How to choose the right air blower for your application

There is an extensive variety of industries in Saudi Arabia that reqire low-pressure blower and compressor, including wastewater treatment, fish farming, food and beverage, cement plants, oil & gas. Given that each application has unique need and requirements, it makes sense that users will place weight on different purchasing factors when choosing which type of low pressure air blowers will best suit their demand!

A thorough analysis of the installation and application is key to selecting the right technology, and there will undoubtedly be one or more aspects that may take precedence over others. For example, a smaller space for the blower might dictate choosing a technology with a smaller footprint and lower noise levels, while an application that requires lower energy costs may be best suited for an energy-efficient technology with a higher initial cost. Key factors that should be taken into consideration include:

A correctly sized blower installation will help to achieve a more energy-efficient process. For instance, in a situation where compressor with pressure reducers is used to achieve low-pressure air, replacing the compressor with an air blower to deliver below 3 bar(g) air will result in significant savings. For every 1 bar(g) the air is compressed above the actual demand, 7% of energy is wasted.

Site conditions have a bearing on blower choice. For example, dusty environment or hot humid site for a blower installation might dictate the choice of a technology offering a reliable positive displacement screw, lobe blower or multistage centrifugal to provide a reliable source of low-pressure air that is less sensitive to dust or high ambient temperatures. On the other hand, the application criterion of lower energy costs may be best met by a more energy-efficient technology that comes with a higher capital cost.

The cheapest solution to purchase does not automatically result in the lowest operating costs. It is therefore advisable not only to consider the investment costs in the design phase, but also to evaluate necessary expenses over the entire life cycle of the machines to get the maximum ROI.

Total cost of ownership (TCO) and Return on Investment (ROI) is an important deciding factor during blower selection to ensure both investment and operational costs are optimized, over 80% of a blower’s lifecycle cost is taken up by the energy it consumes.

Below video is a discussion of total cost of ownership in the application of wastewater treatment, where Atlas Copco was able to support our end-users’ vision of optimized TCO and limit the environmental impact from continuous blower operation:

A feature of the latest generation of low-pressure blowers is intelligent baffle and canopy design that provides reduced sound levels down to 70dB(a) for an improved working environment. Consequently, installation costs are reduced as there is no need for the provision of noise-insulated rooms and doors. 

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.

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.

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.

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 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.

Over 80% of a blower’s lifecycle cost is taken up by the energy it consumes. Moreover, the generation of compressed air can account for more than 40% of a plant’s total electricity bill. Selecting a Variable Speed Drive technology can lead to major energy savings while also helping protect the environment for future generations.

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!