The smallest blowers we sell are Side Channel / Regenerative blowers capable of producing differential pressures to 8 PSIG (550 mbar) at airflows to 400 SCFM (680 Sm3/hr). We generally recommend them for airflows below 150 to 200 SCFM (250 to 340 Sm3/hr) per blower, due to the inefficiency of this type of blowers which becomes more noticeable at higher airflow rates.
These blowers are quiet, reliable, and operate with little maintenance(mostly just checking and replacing inlet air filters) compared to other types of blower.
Positive Displacement Blowers
Positive Displacement / Roots ® Type Blowers are the workhorses of our industry. Most small to medium sized wastewater plants operate with positive displacement blowers which have a useful range to 2500 SCFM (4300 Sm3/hr) per blower at pressures to 14.5 PSIG (1 Bar).
Positive Displacement (or PD Blowers) can be noisy and do require regular maintenance for lubrication of bearings, changing inlet filter cartridges, and tensioning and replacement of belts. SSI provides a solution to blower noise. We can reduce noise through the use of acoustic cabins and proper chamber absorptive silencers. One must be mindful of air noise which can show up in the yard piping at higher airflow rates and pulsation levels. PD blowers operate very efficiently in this airflow range.
Centrifugal Blowers
Multistage Centrifugal Blowers are recommended for larger plants which require more than 2500 SCFM (4300 Sm3/hr) per blower at pressures to 14.5 PSIG (1 Bar). Multistage centrifugal blowers operate relatively quietly compared to PD blowers, with similar maintenance as it relates to lubrication and filters (though they are usually direct drive vs. PD's which are usually belt driven).
Control Systems
For larger plants, it makes sense to consider automated airflow control through the use of either Dissolved Oxygen (DO) probes or a newer system
patented by
another
company which is
said to be more efficient than DO called
feed forward
(off-gas
based). SSI does not manufacture its own control systems, but we will include them in our offer by request or make introductions to specialists in this field who do make the systems.
