Air Separator

Fischer Air Separator & Dry Sand Washer

The Fisher Air Separator – Less Water, Less Waste

“The 13’ diameter Fisher Air Separator effectively removes unwanted fines from aggregate products, bringing otherwise rejected material into specification. Its ability to “dry” process materials and remove excess fines promotes an efficient and clean operation. Portable or stationary units available.

“Field Proven”

The Fisher Air Separator is field proven in abrasive and non-abrasive applications and has achieved successful separation of unwanted fines in limestone, granite, trap rock, basalt, silica, sand and gravel operation.

“Designed with the portable contractor in mind”

Designed with the portable contractor in mind, the Fisher Air Separator is easily set up, disassembled and transported. Within a few hours, the Fisher Air Separator will be ready to clean and classify your aggregate materials.”


  • Designed for up to 150TPH OF 3/8” (10mm) minus product
  • 75HP 1200RPM Electric Motor with V-Belt Drive and Jack Shaft Assembly
  • Cutler Hammer SVX9000 100HP AC Inverter Drive
  • Automatic Lubrication System on Timer to Main Bearing, Pinion Bearing, Labyrinth Seals and Dust Rings
  • 10HP 1800RPM Electric Motor Hydraulic System with Dual 6.5” x 48” Lift Cylinders and Lift Assembly for Ease of Setup and Tear Down
  • Triple 10’ 22,500# Hub Piloted Axles with Brakes, Mechanical Suspension and 285/75R 24.5 Low Profile Tires
  • Heavy Duty Beam Chassis Frame
  • Martin ½ HP Vibrator
  • Special Designed Wear Liners Bolted in Wear Areas
  • 18” x 34’ Feed Conveyor with 7.5HP Motorized Head Pulley with Full Length Covers and Skirted
  • (2) 18” x 24’ Discharge Conveyors with 7.5HP Motorised Head Pulley with Full Length Covers and Skirted
  • Removable Electrical Panel Stand with Controls and 150’ of Power Cord
  • Available as Stationary Unit (No Chassis or Conveyors Included)
  • All Electrical Controls Designed for Country Electrical Source
  • US Patent No. 6,290,071
  • 5th Wheel = 25,640#  Tripple Axles = 39,540#


The Air Separator was introduced into South Africa in 2010. The concept has been tried and tested on the following material.


Aggregate Quarries

The Fisher Air Separator has been very successful in removing unwanted fines for Asphalt and Ready Mix Concrete without the use of water.

The Following companies have purchased the Air Separator :

  • Raubex Bloemfontein
  • SPH Cape Town
  • Independent Quarries East London
  • Great Karroo Crushing ( Head Office Cape town
  • Blasting and Excavating
  • OMV Stilfontein
  • Afrimat Port Elizabeth
  • Lafarge Port Elizabeth
  • Doorning Crushers Kokstad
  • Blasting and Excavating


The unit has successfully been tested at Namakwa Sands for the separation of mineral sand

  • SAK  Lime stone
  • Alpha sand Pretoria. Natural sand



Diamond Mining

The unit was first Tested for a company called Firestone Diamond . The GM at the time was Jan Louw

The First test run was at Bontekooi Mine , between Springbok and Kleinsee.

The material was 0-6mm and we needed to remove as much of the “ super fines “ as possible. The reason behind this was that when washing / jigging , the 1mm diamonds were being washed away in the process and the water usage is very high .

The controlled test involved running 200tons of material at about 90 tons / hour with a fan speed of 60 htz . We put into the feed material 100 traces with a mixture of weights between 100 and 350 gms. The reason for this was to ascertain how many tracers would be taken out on the super fines.

We removed approx. 11% of the fines. These fines were sifted with cake sifters ( which took a week) to check for tracers . There were no tracers found in the fines.

The conclusion was that using the unit before washing would be more effective in reclaiming smaller diamonds and the water saving would be in the region of 80%

We did the same test at Kimberley West Diamond mine . Although the material was wet , the same results were achieved.

A test was also done on material from Leqhobong mine . Please see attached


Iron Ore

Thabazimbi Iron Ore Anglo

This project was to remove a percentage of the -330 micron sixe fines from an input 0-8.

There was a stock pile of 200,000 tons which was classed as waste as the fines content of the material was around 15%. This was an issue for the foundry in Vereeniging. SPH purchased the unit and completed the project in 6 months. 8 % of the fines were removed.

The course material became a sellable product , and the plan was to pelletize the fines for export to China


Dirro Afrimat

Afrimat  purchased Diiro Iron ore mine . There was a Waste dump that they were selling to Khumba. 0-8mm. Khumba needed the fines to be removed at -800micron.

To achieve this they used an Air Separator . The settings were 140 tph with a fan speed of 65htz.  We did 160,000 tons in for months.

In both the above scenario’s the wear rate of the wear parts were very minimal considering the tonnage. There were times in the stockpile that the material was between 8 and 40mm which caused minimal damage to the unit.


The key to the success of unit is based on:

  • Type of material
  • SG of  the material
  • Percentage of fines to be removed and at which cut off point.


The moisture content , tons per hour and fan speed based on the above parameters