With economic development and accelerated urbanization, the amount of wastewater generated from our daily lives, urban activities, and industrial production is increasing daily. This wastewater eventually converges through a complex network of pipes to waste water treatment plants, undergoing a remarkable "purification journey."
At waste water treatment plants, sewage undergoes a series of physical, chemical, and biological treatment processes, with the biological treatment stage being particularly critical. This stage cannot proceed efficiently without a key piece of equipment - the air blower, which aerates the water to increase oxygen content and promote aerobic microorganisms to degrade organic matter, thereby removing oxidizable precipitable substances.
During the waste water treatment process, the air blower is primarily responsible for providing sufficient oxygen to the aeration tank to promote the metabolism of aerobic microorganisms. These microorganisms feed on organic pollutants in the water, converting them into carbon dioxide, water, and microbial cell material, thereby purifying the wastewater.
Without the air blower, this process cannot proceed efficiently, and the waste water treatment plant would essentially become just a storage pond. The performance of the air blower directly affects both the effectiveness of waste water treatment and energy consumption, making the selection of the appropriate type of air blower crucial.
The Roots air blower is a positive displacement blower whose delivered air volume is proportional to its rotational speed. The three-lobe impeller performs three suction and exhaust operations with each rotation of the two impellers. Advantages include minimal gas pulsation, small load changes, high mechanical strength, low noise, minimal vibration, simple structure, smooth operation, and stable performance. Disadvantages include high noise levels at higher flow rates and pressures, and relatively low efficiency with higher energy consumption. Roots blowers are mainly used for small municipal wastewater and industrial wastewater treatment plants, particularly suitable for CAST process wastewater treatment plants.
The working principle of the centrifugal blower is that when the motor rotates and drives the blower impeller to rotate, the gas between the blades in the impeller also rotates and is thrown out under the action of centrifugal force, thereby increasing the gas flow velocity. Advantages include the ability to provide high pressure output, compact design suitable for space-limited locations, and high operating efficiency with relatively low energy consumption. Disadvantages include the inability of single-stage high-speed centrifugal blowers to use frequency conversion speed regulation, low efficiency at partial loads, and unsuitability for handling media containing large amounts of dust or corrosive gases. Centrifugal blowers can be further divided into traditional centrifugal blowers and new magnetic levitation centrifugal blowers. Magnetic levitation centrifugal blowers use magnetic levitation bearing technology, have no mechanical wear, low energy consumption, and semi-permanent service life.
The oil-free screw blower is a new type of blower equipment that has emerged in recent years. It uses a dry oil-free twin-screw main unit with no lubricating oil participating in the compression process, ensuring 100% oil-free compressed air. Advantages include oil-free compressed gas meeting high-standard oil-free compressed air requirements, the use of permanent magnet frequency conversion motors, intelligent speed matching, significant energy saving effects, simple structure, and low maintenance costs. Disadvantages include higher initial investment costs and higher requirements for operating environment and maintenance.
The working principle of the oil-free screw blower can be divided into three processes: the suction process, internal constant pressure transmission, and external compression and exhaust process. Its core technology uses a combination of labyrinth seals and carbon ring seals to achieve oil and gas isolation between the compression chamber and the lubrication chamber, ensuring 100% oil-free air. This type of blower uses advanced coating technology, resulting in smaller rotor clearances, improved volumetric efficiency, effective rotor protection, and extended service life.
The Elang Compressor’s oil-free screw blower combines advanced domestic and international technologies with the following outstanding advantages. High efficiency and energy saving achieved through permanent magnet frequency conversion motors that intelligently match speed to ensure stable exhaust pressure with energy saving rates reaching 15-30% or higher. Completely oil-free operation using labyrinth seals plus carbon ring seals combination to achieve oil and gas isolation between compression chamber and lubrication chamber ensuring 100% oil-free air. Adequate pressure and large air volume exceed the technical limitation of 80kPa for traditional Roots blowers, increasing the pressure to 200kPa, expanding its application range. The air volume range covers 3-100m³/min, meeting the needs of different scales of sewage treatment. High quality and long life through aviation technology super coating with smaller clearance ensuring efficiency and durability while using world-famous brand bearings to ensure reliability. Intelligent control through mature operating control systems with control screen as human-machine interface for human-machine dialogue and fully automatic operation with detection of operating data such as exhaust pressure and temperature.
Our oil-free screw blowers can be widely used in waste water treatment, textiles, chemical fibers, papermaking, steel, power generation, cement, automotive painting, glass, coal mining, grain, petrochemicals and other industrial fields.
Choosing the right air blower requires consideration of multiple factors:
Treatment scale: Small sewage treatment plants can choose Roots blowers or small screw blowers; large sewage treatment plants should choose centrifugal or large screw blowers.
Water quality characteristics: Treating high-concentration industrial wastewater requires higher oxygen transfer efficiency, and a blower with better air supply stability should be selected.
Energy consumption requirements: For equipment that runs for a long time, high-efficiency and energy-saving blowers should be given priority. Although the initial investment is higher, the long-term operating cost is lower.
Maintenance capability: If the plant's maintenance capacity is limited, a blower type with a simple structure and easy maintenance should be selected.
Environmental requirements: In places where there are strict requirements on noise (such as near residential areas), low-noise blowers (such as screw blowers) should be selected.
The air blower mainly provides oxygen to the aeration tank promoting aerobic microorganism metabolism to decompose organic pollutants in water serving as the core equipment in the biological treatment stage.
Oil-free screw blowers provide 100% oil-free compressed air with high energy efficiency low noise (<85 decibels) simple maintenance and suitability for occasions requiring high air quality.
Factors such as treatment scale, water quality characteristics, energy consumption requirements, maintenance capabilities, and environmental requirements need to be considered. Small plants can choose Roots blowers, while large plants should choose centrifugal or screw blowers.
It depends on the type of air blower. Roots air blowers require regular maintenance while oil-free screw blowers have lower maintenance requirements. However all air blowers require regular inspection to ensure optimal performance.
Frequency conversion control adjusts motor speed to match load demand avoiding energy waste. Theoretically when speed is reduced by half power can be reduced to 1/8 of the original with significant energy saving effects.
The service life of an air blower depends on the working environment maintenance situation and product quality. Generally high-quality air blowers have a design life of over 15 years while magnetic levitation blowers may have a semi-permanent service life due to their non-contact characteristics.
As an "invisible hero" in the field of waste water treatment, air blowers play a vital role in our water environment protection. With technological development, new equipment such as oil-free screw blowers are providing more efficient, energy-saving and reliable solutions for the waste water treatment industry.
Our Elang Compressor will continue to commit to providing customers with high-quality oil-free screw blower products and technical support, contributing our strength to protecting water resources and the ecological environment. Next time you see clear river water or smell flowers, you might remember these silently working "invisible heroes" - air blowers.
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