Air-O-Latorformulated by Air-O-Lator Corporation
InterMix Gear Reduced Submersible Mixer
Air-O-Lator InterMix gear-reduced submersible mixer, 5 to 15 HP. A planetary reducer turns a 26 or 30 inch propeller slowly for 13,000 to 21,000 GPM.
What it is
The InterMix Gear Reduced is a submersible wastewater mixer with a planetary gear reducer between the motor and the propeller. The reducer lets a 26 or 30 inch propeller turn at 300 to 430 RPM, which moves far more water than a direct-drive unit of the same horsepower: 13,000 GPM at 5 HP against 4,000 GPM direct drive. Built for raw, screened wastewater.
Buy this when you are seeing
- Solids settling out across a large lagoon cell or digester
- A sludge blanket that resettles between aeration cycles
- Stratification in a deep cell with an anoxic bottom
- Chemical short-circuiting straight to the outfall
- A basin a direct-drive mixer cannot turn over
How it works
A planetary gear reducer sits between the motor and the propeller. That single component is the whole product. It trades shaft speed for torque, which lets the same frame turn a propeller two and a half times the diameter of a direct-drive unit at roughly a fifth of the speed.
The result is a completely different flow character. Compare the two 5 HP InterMix models: direct drive moves 4,000 GPM through a 10 inch propeller at 1,735 RPM; gear reduced moves 13,000 GPM through a 26 inch propeller at 300 RPM. Same motor, same power draw, more than three times the water. A large slow propeller is simply a more efficient way to move volume.
Volume and throw are what mix a lagoon. A fast narrow jet loses its energy to turbulence within a short distance of the nozzle; a large slow column keeps its coherence and carries across the basin, which is why the gear-reduced family is the one specified for cells, digesters and sludge holding tanks rather than wet wells.
Propeller bearings are housed separately in the fairwater rather than being carried by the motor. On a machine built for raw screened wastewater that is a service-life decision: the side loads from a 30 inch propeller in solids-laden water are taken by dedicated bearings instead of the motor shaft.
The motor is a Baldor three-phase continuous duty unit with Class F insulation, UL listed for Class 1, Group D, Division 1 explosion-proof service, supplied with a 30 foot power cord. That listing is what lets it go into a digester or a covered basin where a gas atmosphere is credible.
Check these before you buy
These decide whether this product can work at all. If one fails, fix that first, because the money spent here will not survive it.
- Know your basin working volume and your target turnoverMixer selection is volume divided by pumping rate. Without a working volume in gallons and a turnover time your engineer or state standard is asking for, horsepower is a guess. This is the single number to have before you call.
- Confirm screening upstreamThe family is built for raw, screened wastewater. Rag and grit loads that get past screening wrap propellers and shorten bearing life on any mixer, and no amount of horsepower fixes it.
- Source the 4 inch square tube mast locallyThe 304 stainless motor support and mount ship with the unit; the mast itself does not. Confirming who supplies and sets it is the most common gap between a quoted price and an installed system.
- Confirm three-phase power and the explosion-proof requirementThis family is 230V or 460V three-phase. If the installation is in a classified area, confirm that the Class 1, Group D, Division 1 listing matches what your electrical inspector expects for that space.
- Check what is above the mastThe mount is designed so the mixer is raised, lowered and removed without entering the tank. That only works if there is headroom and access above the mast for a boom or hoist to pull it.
Is this the right fit
Good fit for
- Large lagoon cells, digesters and sludge holding tanks
- Basins where the duty is measured in turnover time rather than local velocity
- Keeping a sludge blanket in suspension between aeration cycles
- Deep cells that stratify
- Classified areas needing the Class 1, Group D, Division 1 listing
Not the answer for
- Compact basins, wet wells and lift stations, where direct drive is the right and cheaper unit
- Fast local dispersion of a chemical or polymer, which wants velocity rather than volume
- Sites with only single-phase power
- Adding dissolved oxygen, which is an aerator's job and not a mixer's
Dosing and application
- Sizing basis
- Basin working volume divided by the unit's pumping rate gives a turnover time. Most mixing duties are specified as a target turnover rather than a horsepower, and that is the number to bring to a quote.
- Mounting
- 304 stainless motor support and mount fitting a 4 inch square tube mast, sourced locally. Allows raising, lowering and removing the mixer without entering the tank.
- Motor
- Baldor three-phase continuous duty, Class F insulation, UL listed for Class 1, Group D, Division 1 explosion-proof, with a 30 ft power cord.
- Voltage
- 230V or 460V, three-phase. Confirmed at quote.
- Operating depth
- Rated to 30 feet, in open or closed tank configurations.
- Propeller bearings
- Housed separately in the fairwater, so propeller side loads are not carried by the motor.
- Sold separately
- Guide-rail mast, motor starter protector and submersible power cable. We quote them with the unit.
- Construction
- Manufactured in the United States, designed for a 15 to 20 year service life.
What to expect, and when
- Hour oneMixing starts on energisation. On a large cell, expect the surface signature to take longer to appear than you think, because the work is happening in the column.
- First weekTake depth-profiled solids samples at several stations. A mixer's job is measured by how uniform those profiles become, not by what the surface looks like.
- First monthStratification should be gone at the sampled stations. A station that stays stratified usually means aim or position rather than insufficient horsepower.
- First yearPull the unit on the guide rail for inspection at the interval the manufacturer specifies. The mast mount exists precisely so this is a deck job.
How you prove it worked
Profile total suspended solids at three or more stations, at top, middle and bottom, before the mixer goes in and then on a fixed schedule after. A mixer is working when those nine numbers converge. Surface appearance proves nothing: a cell can look perfectly turned over and still hold a stratified anoxic layer at the bottom, which is the exact failure a mixer is bought to end.
There is one component in this mixer that explains the whole product, and it is the planetary gear reducer sitting between the motor and the propeller.
Without it, a 5 HP submersible motor spins a 10 inch propeller at about 1,735 RPM and moves 4,000 gallons per minute. With it, the same 5 HP motor turns a 26 inch propeller at 300 RPM and moves 13,000 gallons per minute. Identical power draw, more than three times the water. Large and slow beats small and fast when the job is volume, and in a lagoon cell the job is always volume.
Why volume rather than velocity
A high-velocity jet dissipates. It converts its energy into turbulence within a fairly short distance of the discharge, which is excellent if the thing you need to mix is right there and useless if it is eighty feet away. A large, slow-moving column of water holds together and carries. That is what gets a basin turning over as a whole rather than developing a well-mixed zone near the unit and a stagnant one everywhere else.
This is why the gear-reduced family is the one specified for lagoon cells, digesters and sludge holding tanks, and why the direct-drive family belongs in wet wells and lift stations.
Built for the water it actually goes in
Two details matter more than the datasheet suggests. The propeller bearings live in the fairwater, separate from the motor, so the side loads a 30 inch propeller generates in solids-laden water are carried by bearings chosen for that job rather than by the motor shaft. And the Baldor motor carries Class F insulation with a UL listing for Class 1, Group D, Division 1 explosion-proof service, which is what permits a digester or covered basin installation at all.
Air-O-Lator builds these in the United States and designs them for a 15 to 20 year service life. Over that span the guide-rail mount is worth as much as the machine: the 304 stainless mount rides a 4 inch square tube mast so the mixer is raised, lowered and pulled from the deck. Nobody enters the tank.
Sizing, and the one number to bring
Mixer sizing is arithmetic once you have the inputs: working volume in gallons divided by pumping rate in GPM gives turnover time in minutes. Most specifications and state standards express a mixing duty as a target turnover rather than a horsepower, so that is the number worth having before you shop.
Send us the volume and the turnover you are being asked to hit. We will run the options against the published pumping rates and tell you honestly if the answer is a smaller unit than you expected, or if it is two units rather than one.
Specifications
| Type | Submersible mixer, planetary gear reduced |
|---|---|
| Horsepower range | 5 to 15 HP |
| Pumping rate | 13,000 to 21,000 GPM |
| Propeller RPM | 300 to 430 |
| Propeller diameter | 26 or 30 in |
| Thrust | 200 to 600 lbs |
| Max operating depth | 30 ft, open or closed tank |
| Propeller bearings | Separate, housed in the fairwater |
| Motor | Baldor three-phase continuous duty, Class F insulation, UL listed Class 1 Group D Division 1 explosion-proof, 30 ft cord |
| Voltage | 230V or 460V three-phase |
| Mounting | 304 stainless mount for a 4 in square tube mast, sourced locally |
| Construction | Made in USA, designed for 15 to 20 year service life |
Works alongside
InterMix Direct Drive Submersible Mixer
The same frame and mount in a high-velocity configuration, for the compact basins and wet wells where a 30 inch propeller has nowhere to work.
Aquarian Quantum Surface Aerator
A mixer moves the cell but adds little oxygen. Where both duties are real, the usual answer is a mixer for the column and surface aeration for the transfer.
Common questions
Why choose gear reduced over direct drive?
Volume. At 5 HP the gear-reduced unit moves 13,000 GPM through a 26 inch propeller at 300 RPM, while the direct-drive unit moves 4,000 GPM through a 10 inch propeller at 1,735 RPM. Same horsepower, more than three times the flow, because a large slow propeller moves water more efficiently than a small fast one. If your duty is turning over a big basin, that is the number that matters.
Then why would anyone buy direct drive?
Because a 30 inch propeller needs somewhere to work, and because velocity is sometimes the point. In a wet well, a lift station or a chemical mixing application you want a fast tight jet in a small space, and the direct-drive unit is both better suited and several thousand dollars cheaper.
What size do I need?
Take your basin working volume in gallons and divide by the unit's pumping rate in GPM. That gives a turnover time in minutes, which is how mixing duties are usually specified. Send us the volume and the turnover your engineer or state standard wants and we will work through the options with you.
Is the mast included?
No. The 304 stainless motor support and mount ship with the mixer, but the 4 inch square tube mast is sourced locally. This is the most common surprise in a mixer budget, so we call it out at quote rather than after.
Do I have to enter the tank to service it?
That is exactly what the guide-rail mount is designed to avoid. The mount rides the mast so the mixer can be raised, lowered and removed from the deck. Confirm you have headroom and hoist access above the mast, because that is what makes it work in practice.
Can I put one in a digester?
The motor is UL listed for Class 1, Group D, Division 1 explosion-proof service, which is the listing that makes a digester or covered basin installation possible. Confirm the classification of your specific space with your electrical inspector before ordering.
Will it raise my dissolved oxygen?
Not meaningfully, and you should not buy it for that. A mixer moves water; an aerator transfers oxygen. Mixing can help by breaking stratification and stopping an anoxic bottom layer forming, but if your problem is a DO number then an aerator is the purchase.
Read before you buy
Lagoon Sludge Removal: Costs, Options, and How to Decide
Dredging vs biological sludge reduction for wastewater lagoons: real cost ranges, how to measure your sludge blanket, and a decision framework.
SludgeLagoon Sludge Judging: How to Measure Your Sludge Blanket
The grid method for profiling a wastewater lagoon sludge blanket, the tools it takes, and how to convert probe readings into volume and dry tons.