A Comprehensive History of Six Generations of Blower Technology: A Century of Industrial Innovation, from Mechanical Transmission to Oil-Free Suspension

Introduction

Blower Renowned as the industrial system’s Industrial lung lobe , serving a wide range of industrial applications—including municipal wastewater treatment, chemical processing, textile dyeing, aquaculture, pneumatic conveying, and new energy—each with capacities in the tens of millions. Over the past 170-plus years, blowers have evolved along… Volumetric air delivery → Low-speed centrifugal → Gear-driven high-speed centrifugal → Contactless suspension direct drive With complete iterations, the industry has established a widely recognized six‑generation technical classification: Roots blowers, screw blowers, multi‑stage centrifugal blowers, single‑stage gear‑driven centrifugal blowers, magnetic‑levitation centrifugal blowers, and air‑bearing centrifugal blowers.
　　With each generational shift, the underlying essence is always to address the shortcomings of the preceding generation. Friction losses, oil leakage contamination, elevated energy consumption, cumbersome operation and maintenance, and excessive noise levels. The five major core pain points are underpinned by a century‑long technological revolution that integrates fluid dynamics, bearing materials, permanent‑magnet drives, and aerospace‑military technologies. Drawing on industry historical records, patent timelines, and milestones in commercial deployment, this paper comprehensively traces the evolution of blowers across all generations, clarifying their technical origins, performance trade‑offs, and emerging industry trends.

I. First Generation: Roots Blowers—The Pioneering Positive-Displacement Blower (Born in 1849)

Origins and Historical Development of Technology

In 1849, the Roots brothers in the United States invented the two‑lobed positive‑displacement blower, which entered industrial mass production in 1867 and was initially used for mine ventilation. In the 1950s, China imported and replicated this technology, making it the first generation of widely adopted blowers in the country; to this day, it continues to hold a significant share of the domestic market.

Core Working Principle

A pair of synchronizing gears drives the conjugate impellers to rotate; there is no internal compression within the chamber, and air is forcibly conveyed by volumetric displacement. The entire unit is supported and operated by rolling bearings and a lubrication system.

Technical Features and Applicable Scenarios

Advantage : Extremely simple structure, low manufacturing cost, stable airflow under low-flow, low-pressure conditions, and very low maintenance requirements.
　　 Inherent weaknesses : The airflow exhibits severe pulsations, with operating noise exceeding 95 dB; continuous mechanical friction between gears and bearings results in the highest energy consumption across all product categories; lubricant leakage can contaminate the air supply; and the flow‑rate adjustment range is narrow, leading to a sharp drop in efficiency at low loads.
　　 Application : Small-scale aquaculture aeration, micro‑powder conveying, small‑scale township wastewater treatment, and low‑pressure temporary gas supply.

Industry Positioning

At the outset of the blower industry, this was the foundational model in the positive-displacement technology segment, suitable only for low‑end projects with limited budgets and simple operating conditions; it has been gradually phased out in dual‑carbon energy‑saving retrofits.

II. Second Generation: Screw Blowers | Optimized and Upgraded Positive-Displacement Technology (Commercialized in the 1960s)

Origins and Historical Development of Technology

The technology originated from screw air compressors. In the 1960s, European manufacturers optimized the profile of the screw rotor and adapted it for low-pressure blowers, introducing it to the market as an evolutionary successor to Roots blowers. Following the year 2000, domestic production and mass manufacturing were achieved in China.

Core Working Principle

The yin–yang screw rotors mesh and rotate, achieving pre-compression within the chamber. It also employs gear‑driven synchronous transmission and an oil‑lubricated bearing system, classifying it as an improved positive‑displacement air‑delivery device.

Technical Features and Applicable Scenarios

Advantage Compared with Roots blowers, airflow pulsation is significantly reduced, noise is improved by approximately 10 dB, and overall energy efficiency under the same pressure conditions is enhanced by 10% to 15%.
　　 Inherent weaknesses : Unable to decouple from the lubrication oil circulation system, posing a risk of oil‑gas contamination; high‑pressure, high‑flow models have bulky housings, and their gearboxes, operating at high speeds for extended periods, require frequent overhauls with short service intervals.
　　 Application : Aeration for small and medium-sized wastewater treatment, general gas supply for chemical processes, and standard gas sources for food processing (requiring a downstream precision oil‑removal unit).

Industry Positioning

A flagship product of the positive-displacement technology platform, positioned between low-end Roots blowers and high-end centrifugal fans, serving as a transitional model for mid-range small and medium-sized projects.

III. Third Generation: Multi‑Stage Low‑Speed Centrifugal Blowers | The Starting Point for the Widespread Adoption of Large‑Scale Centrifugal Technology (Mass Commercialization in the 1980s)

Origins and Historical Development of Technology

The theoretical foundations of centrifugal fluid mechanics were established in 1862; however, limitations in motor speeds and bearing materials long prevented the practical implementation of industrial‑scale boosting. In the 1980s, a multi‑impeller, series‑connected staged‑boosting configuration matured, becoming the standard equipment for large municipal wastewater treatment plants.

Core Working Principle

Multi‑stage, series‑connected impellers for binary‑flow compression; a low-speed induction motor coupled with an external gearbox for speed increase; sliding bearings supported by a large lubrication oil station; and continuous air compression achieved through centrifugal force, resulting in pulsation‑free airflow.

Technical Features and Applicable Scenarios

Advantage : Provides stable high‑volume air output, smooth airflow, and noise levels lower than those of positive‑displacement blowers; ideally suited to meet the basic aeration requirements of large wastewater treatment plants with capacities in the tens of thousands of tons.
　　 Inherent weaknesses : The unit is bulky and occupies a large footprint; its flow‑rate adjustment range is limited to 60%–100%, resulting in significant energy waste at low loads; the lubrication system features a complex piping layout, requiring annual replacement of substantial quantities of oil and filters, and necessitating a major overhaul of gears and bearings every 5 to 8 years.
　　 Application : In the early years, large-scale municipal wastewater treatment plants, boiler air supply for power plants, and gas supply for major metallurgical processes were constructed.

Industry Positioning

The first-generation centrifugal fan addressed the pulsation issues of positive-displacement blowers, but it failed to overcome the bottlenecks of high energy consumption and elevated maintenance costs associated with mechanical drive systems.

IV. Fourth Generation: Single-Stage Gear-Driven Centrifugal Blowers | Ternary Flow Technology Delivers a Leap in Efficiency (Matured and Commercialized in the 1990s)

Origins and Historical Development of Technology

As Simulation Design Theory for Three-Dimensional Flow Impellers In commercial applications, the industry abandoned multi‑stage series‑connected designs in favor of a single high‑efficiency ternary impeller paired with a high‑speed gearbox to achieve compression. By the 1990s, this configuration had become the mainstream high‑end model on the market prior to the widespread adoption of suspended blowers.

Core Working Principle

A single-stage, high-precision three-dimensional impeller boosts the motor speed to tens of thousands of RPM via a precision gear‑reduction gearbox; axial inlet guide vanes regulate airflow, while sliding bearings are paired with an integrated lubrication station, balancing flow control with overall weight reduction.

Technical Features and Applicable Scenarios

Advantage : The single-stage design significantly reduces weight and footprint; the three‑dimensional aerodynamic design boosts efficiency by more than 10% compared to multi‑stage centrifugal compressors; the flow‑rate adjustment range is expanded to 45%–100%, delivering substantial energy‑saving benefits under varying operating conditions; and start‑stop response is faster, eliminating the need for complex energy‑storage systems.
　　 Inherent weaknesses : The high-speed gearbox is a critical wear component, subject to wear during prolonged continuous operation; the lubrication system cannot completely eliminate trace amounts of oil mist and gas; and the lengthy shutdowns required for periodic overhauls of gears and bearings keep lifecycle maintenance costs persistently high.
　　 Application : The mainstream gas‑supply equipment for medium‑sized wastewater treatment plants, textile dyeing, papermaking, chemical processing, and metallurgy; prior to 2010, it was the preferred high‑end model for environmental protection projects.

Industry Positioning

The technological ceiling of conventional mechanical‑drive blowers, and the core benchmark product against which oil‑free suspended blowers are fully benchmarked.

V. Fifth Generation: Magnetic‑Levitation Centrifugal Blower | Electromagnetic Levitation, Zero Contact Throughout, Oil‑Free (Commercialized Worldwide in 1996)

Origins and Historical Development of Technology

The theory of magnetic‑levitation bearings originated in European and American laboratories in the 1960s, but its commercialization was long hindered by limitations in power‑electronics control technology. In 1996, a Swiss company launched the world’s first industrially produced magnetic‑levitation blower. In 2009, a domestic enterprise successfully commissioned China’s first domestically manufactured magnetic‑levitation blower, marking the official start of the country’s drive to localize oil‑free blower technology.

Core Working Principle

Active electromagnetic bearings use electromagnetic forces to support the rotor throughout its entire operating range, eliminating mechanical contact during all phases of operation. They eliminate the need for gearboxes and lubrication oil stations, enabling direct drive of a high-speed permanent‑magnet motor coupled to a three‑dimensional flow impeller, and are paired with a fully digital variable‑frequency control system.

Technical Features and Applicable Scenarios

Advantage : Friction-free operation throughout the entire process, delivering 100% oil-free, clean compressed air; compared with gear-driven single-stage centrifugal compressors, it achieves overall energy savings of more than 30%; extremely low vibration and noise levels ≤80 dB; supports frequent start–stop cycles and requires no major bearing overhaul for ten years; offers a wide flow‑rate adjustment range and outstanding performance under high-pressure conditions.
　　 Inherent weaknesses : The overall equipment procurement cost is relatively high; the electromagnetic control system is highly precise, and in harsh, high-dust environments, enhanced pre‑filtration is required; moreover, the maintenance of electrical control components demands a high level of expertise.
　　 Application : Ultra-large-scale municipal wastewater treatment, high-pressure chemical processing, lithium‑ion battery energy, pharmaceutical aseptic gas supply, and high‑purity specialty processes.

Industry Positioning

The first-generation contactless levitation fan—a high-end model designed specifically for high-pressure, ultra-clean environments and applications involving frequent start‑stop cycles.

VI. Sixth Generation: Air-Suspension Centrifugal Blower | Military‑grade air‑film bearings adapted for civilian use, the king of energy efficiency and cost‑effectiveness (commercially available since 2002)

Origins and Historical Development of Technology

The foundational theory of air‑bearing technology originated in the U.S. aerospace sector in 1947, with the development of hydrodynamic foil‑bearing technology to address the challenge of high‑speed friction in fighter‑jet turbine engines; it is a quintessential example of military‑grade fluid‑mechanics technology.
　　In 1997, Professor Shi Ximin’s team at KAIST in South Korea completed the world’s first prototype of an air‑levitation fan and founded… Korean K-TURBO (Tuobo) , in 2002, it achieved the world’s first industrial-scale commercial application at the Seoul Municipal Wastewater Treatment Plant; subsequently, the original core engineering team of K-TURBO spun off to start their own business and launched Turbowin (Tebo Ying) The brand continuously iterates and optimizes its air-cooled designs and power series, expanding the scope of product applications and driving the widespread adoption of air‑suspended blowers across the global environmental protection industry.

Core Working Principle

When the rotor spins at high speed, the foil bearing automatically generates a micron‑scale, high‑pressure air film in the clearance between the foil and the spindle, using aerodynamic lift to suspend the rotor. With no gears and no lubricant, the system features an integrated direct drive from a high‑speed permanent‑magnet motor, coupled with a purely mechanical bearing design that eliminates the need for complex electromagnetic controllers.

Technical Features and Applicable Scenarios

Advantage : Oil-free, clean air supply; overall energy savings of 30%–45%; purely mechanical bearing design for lower failure rates and simplified operation and maintenance; initial equipment purchase cost lower than that of magnetic‑levitation blowers, with significant lifetime electricity‑cost savings; routine maintenance is minimal—only the air filter needs to be replaced.
　　 Inherent weaknesses : During startup and shutdown, the rotor briefly contacts the bearings; industry standards recommend limiting daily start–stop cycles to no more than three. Its maximum pressure rating is slightly lower than that of magnetic‑levitation blowers, resulting in reduced suitability for ultra‑high‑pressure operating conditions.
　　 Application : Widely used as the mainstream model for energy-saving upgrades under the dual-carbon initiative, it serves the vast majority of municipal wastewater treatment, textile dyeing, papermaking, aquaculture, food processing, and small- to medium-sized industrial gas supply applications.

Industry Positioning

Currently, the market’s mainstream energy‑saving, next‑generation products strike an optimal balance among energy efficiency, procurement cost, and ease of operation and maintenance, making them the most cost‑effective solution for industrial green upgrades.

Overview of Core Technology Comparisons for Six Generations of Blowers

III. The Underlying Logic of a Century of Evolution: Three Major Technological Revolutions

1. Revolution in the drive system: from mechanical gears to gearless direct drive

The first four generations of wind turbines all relied on gear‑based speed‑increase systems, leaving the three major pain points—friction losses, oil leaks, and costly overhauls—unresolved. The fifth and sixth generations of suspended‑type wind turbines eliminate the gearbox, integrating a high‑speed permanent‑magnet motor with the rotor to fundamentally reduce mechanical losses.

2. A Revolution in Bearing Technology: From Oil-Lubricated Mechanical Bearings to Non-Contact Levitation Bearings

From rolling bearings and sliding bearings (which rely on oil lubrication), the technology has evolved to electromagnetic levitation and air‑film levitation, completely eliminating the need for lubrication systems and addressing longstanding industry challenges such as air‑source contamination, consumable oil usage, and oil‑line maintenance.

3. Pneumatic and Drive Revolution: Binary‑stage Impeller → Ternary‑flow Impeller + Permanent‑Magnet Variable‑Frequency Drive

Early‑generation fans employed simple two‑dimensional impellers, resulting in relatively low aerodynamic efficiency. Modern suspended‑type fans are equipped with CFD‑optimized three‑dimensional impellers and paired with wide‑bandwidth permanent‑magnet variable‑frequency motors, ensuring high‑efficiency operation across the entire flow range and accommodating complex, variable‑load conditions in industrial applications.

IV. Future Development Trends of the Industry

1. Suspended‑type fans fully replace traditional oil‑lubricated models.  
   Driven by national policies on carbon neutrality and energy conservation, high‑energy‑consumption equipment such as Roots blowers, screw compressors, and gear‑driven centrifugal machines is being phased out at an accelerated pace, while oil‑free suspension technologies—magnetic levitation and air bearing—are becoming standard configurations for both new installations and retrofit projects.
2. Mass-market adoption of air‑suspension blowers  
   Leveraging lower procurement costs and simplified operations and maintenance, air‑suspension centrifugal fans now serve over 80% of typical industrial and municipal gas‑supply applications, making them the primary choice for energy‑saving retrofits.
3. Domestic technologies continue to achieve breakthroughs.  
   Air‑suspended foil bearings, high‑speed permanent‑magnet motors, and ternary impellers—key core components—have all been fully domestically produced, breaking the longstanding overseas technology monopoly and significantly lowering the procurement threshold for end‑use equipment.
4. Intelligent and Digital Integrated Upgrade  
   The next-generation suspended fan is equipped with an IoT-based remote monitoring and predictive maintenance system, enabling real-time tracking of energy consumption, vibration, and temperature to support unattended operation, thereby meeting the requirements of smart factory and smart wastewater treatment plant deployments.

Conclusion

From the invention of the Roots blower in 1849 to the commercial application of air‑suspension technology originally developed for military use in 2002, the more than 170‑year history of blower development has essentially been a relentless pursuit of technologies that reduce mechanical losses and enhance energy efficiency.
　　The fifth-generation magnetic‑levitation and sixth-generation air‑bearing technologies—both oil‑free—are at the pinnacle of today’s blower industry. Among them, air‑bearing blowers, backed by military‑grade reliability, exceptional energy efficiency, and outstanding cost‑effectiveness, are emerging as core equipment in the global industrial green transition, continuously delivering triple value to wastewater treatment and industrial manufacturing: reduced costs, lower carbon emissions, and cleaner production.