Air Knife – Blower Vs. Compressor (an indepth comparison)

Introduction:

In this comparison, we aim to shed light on the operational differences between blowers and compressors, emphasizing that each serves its purpose based on specific applications. This article is intended for informational purposes only and does not seek to undermine the value of either air source.

Operation Principle:

Reciprocating compressors generate pressure through the back-and-forth movement of the piston within the cylinder. In contrast, blowers operate on a rotary principle, consistently producing pressure throughout their operation.

Waste of Energy:

Air compressors are designed for a minimum pressure of 70,000 mm wc, while many Air knife applications require just 2,000 mm wc. The energy required to elevate pressure from 2,000 to 70,000 mm wc results in significant wastage, with more than 97.15% of the compressor’s energy going unused. Even compressors designed for a minimum pressure far exceed typical requirements.

Air Volume:

Comparing air flow, a standard single-stage air compressor (1 HP) produces 6.32 m3/hr, while a single-stage regenerative blower (1 HP) can deliver up to 200 m3/hr. Regenerative blowers excel in moving more than 36 times the volume of air compared to compressors.

Physical Dimensions:

Compressors are typically large due to the need for a storage tank for compressed air. A single-stage 1HP compressor occupies 820mm x 325mm of floor area and takes 765mm vertical space. In contrast, regenerative blowers are more compact, fitting within or under existing machinery/systems, with a single-stage 1HP blower requiring only 390mm x 430mm of floor space.

Running Cost:

Due to the energy wastage in compressors, their running costs are significantly higher than those of air blowers. Air compressors can have running costs up to 62% higher compared to blowers, making the latter a more cost-effective option.

Maintenance Cost:

Regular maintenance is crucial for both blowers and air compressors, but regenerative blowers, being directly driven by an electric motor, have fewer parts, resulting in lower maintenance costs. Compressors, with components like pulleys, belts, bearings, and valves, often incur higher maintenance expenses.