Phone: +021 911 5835; C: 0823903989; T: 0861428716

Positive displacement blowers (Roots type blower) & regenerative blowers (ring bower, side-channel blower)

We supply a range of blowers such as roots type (positive displacement) blowers, ring blowers (side channel/regenerative) and fans. For most water-related (aquaculture) applications a regenerative blower is sufficient, but where higher volumes and or pressures are needed, we have roots blowers to service this function.

Blower parmeters and specifications

Due to the large number of air blower types, models and applications, so be able to quote properly, please advise with as much informaotion as possible about your specificapplication. The following information us useful in selecting the correct air blower:

Brief description of your application;

City or altitude of application;

Air volume required (e.g. cubic meters per hour or liters per minute);

Air pressure needed (e.g. 1 meter of water is 100mbar pressure needed, excluding friction losses etc.;

Distance from blower to furtherest point of air release;

Type of air release, such as air diffuser planned;

Is the environment clean or very dusty?

Type of gas to be conveyed - air or some other gas; Explosive gases need special motors and blowers;

Expected gas temperature;

Is the pressure static (constant) or expected to be variable (e.g. staff are adjusting air flows on the delivery line without consideration of the impact on the blower.

With this information, we can select a suitable blower for your application. Some specialized industrial applications will require a skilled engineer to determine the air pressure needed. Any pressure unit can be provided, although we prefer millibar. USA documents usually report pressure in PSI.

The positive displacement and regenerative blowers serve in both vacuum and air delivery applications.

Blower types include, centrifugal blowers (turbo blowers), multi stage blowers, cooling fans, pressure exhaust fans, dust collectors, roots blowers, side channel blowers, diaphragm blowers, vacuum pumps, and battery operated blowers.

Examples of ring blower applications:

    Medium sized shrimp/fish hatchery, aquaculture, fish pond aeration
    Hydroponics, aquaponics
    Printing and drying
    Biogas boosting and transfer
    Dust collecting
    Bottling industry
    Sewage treatment industry
    Water treatment
    Vacuum and suction applications
    Drying by air flow, air dryer, air knife
    Product conveying (pneumatic material conveying) and loading
    Dust and smoke collection/removal
    CNC machines
Air dryer side channel blower
Central loading
Water treatment
Pneumatic conveying
Material conveying
water aeration
Dust & smoke collection or extraction
Air dryer blowers
Dust removal blower
CNC machine blower
Biogas blower
Air knife blowers

Examples of positive displacement blower applications

Aquaculture, aquaponics, hydroponics, agriculture (e.g. Large shrimp hatchery aeration; dairy: automated milking)

Pneumatic conveying system (food, mining etc.) via pressure or vacuum; dry bulk hauling, solids fluidization (e.g. cement & lime)

Combustion air supply for cement kiln

Waste water treatment, sewage and other environmental

Biogas boosting and transfer: process gas boosting

Various industrial factory applications

    Positive displacement blowers can deliver pressures up to 1,000 mbar. Pipe nominal sizes rangefrom DN 50 to DN 400, depending on the air flow. Intake air volume flows range from 30 m3/hour to 15,000 m3/hour. Intake volume flows in negative pressure up to 500 mbar.

Silent single phase and three phase regenerative (ring) blowers

Regenerative (ring) blowers can perform both an air delivery and vacuum function. For both, there is a maximum volume and a maximum pressure, so you need to select your blower knowing your usage as pressure (or vaccum) and volume needs to fall within these two parameters. Altitude also affects blower selection, especially high altitudes like Johannesburg. This type of blower is also referred to by other names such as Regenerative blower, Ring Compressor, Side channel blower or Vortex Blower. Click to enlarge.
Goorui series 1 blower curves

Blower selection

A typical airstone delivers 5 to 10 liters per minute or up to 600 liters per hour. The 1.5 kilowatt GHBH2R4 above will deliver 80 to 90 cubic meters per hour (m3/h) at 2 meters of water (200mbar) with some allowance for friction losses to pipes, bends  and diffisers. 80 m3/h is 1333 liters per minute of air delivered to a 2 meter water depth. You cannot exceed the perfprmance paraneters of the blower and need to keep witing the extreme limits. The maximum pressure for the 1.5 kilowatt GHBH2R4 is 290mbar. Allowance needs to be made for altitude and friction losses, so this blower would usually deliver to depths of around 2 meters at Johannesburg altitude and possibly 2.5 meters at sea level. The other detail to consider is that at 290mbar pressure, the blower is still delivering 75m3/h. Another usage error that can occur is that even though the water is the correct depth for the blower, the airflow is turned below 75m3/h. The blower design is for a minimum of 75m3/h, so at lower flow rates it will overheat and eventually burn out. The blower must release its air design flow. A third common mistake is to select a delivery pipe that is too small for the blower, leading to excessive pipe friction losses. Always check with us on the delivery pipe size required and be generous rather conservative on the size of the pipe running from the blower to the system.

Side channel blower parts

Regenerative (ring) blowers can perform both an air delivery and vacuum function. The blower engineering design results in a very low-maintenance piece of equipment and the working parts with contact are hight quality, long-life bearings. A range of capacities and 220 volt and 3 phase, 380 volt models are available. These blowers require no maintenance and do not use oil. Deliveries from 0.6 m3/min to 25m3/min are available. In terms of kilowatts these range from 0.15 Kw to 15 Kw. Pressure delivery as mm H20 (milliliters of water head) ranges from 500 mm to 3,500mm. Current amperage ranges from 1.2 to 47 Amp.

Blower parts

Side channel blowers run on the motor bearings and the impellor runs free. The high quality motor bearings have a long life and are replaceable on the larger blowers. Bearings are the onle "working part".

See the generally stocked blower specifictions and prices.
Shop at our Ecotao Store for air blowers.
See more on our side channel blowers (blower curves etc.).

Applications and advantages

Regenerative blowers are suitable for all those applications requiring considerably higher pressures than that which can be achieved using centrifugal fans. Side channel blowers are used in all those applications requiring an operating vacuum or pressure higher than the one achievable by a fan, but not as high as to require the use of a vacuum pump. The rotating parts are not in contact with the casing. There is therefore no friction during operation and thus no internal lubrication is necessary. The gas moving through the machine therefore remains uncontaminated and completely oil-free. The main feature are:

    easy installation
    low noise level
    no vibration and therefore complete dynamic stability
    minimal maintenance (runs on two or 3 bearings)
    Simple Maintenance
    100% Oil Free Air
    Suitable to environment protection
    Small size

For air pressure units conversion, see
Contact us
Telephone: 021-911 5835
Cellular: 0823903989
T: 0861428716
We deliver throughout South Africa and neighboring countries.
Ecotao address
Ecotao Enterprises cc
39 Olienhout Avenue
Plattekloof 3
Cape Town 7500