Air Blast Aggregate Heaters
Gold Mine, Winnemuca, NV 1998
American Geothermal’s Air Blast system is a direct instantaneous aggregate heating system. We can also cool with an optional cooling system addition. The system is designed to direct large volumes of warm air directly through overhead aggregate bins. The system can heat coarse aggregate and sand at rates of up to 200 yards per hour. Since all of the heat is going into the aggregate, the operating cost is far less than other methods of heating aggregate.
Here are some of the Air Blast system benefits:
- Direct heat by gas-fired burners.
- Low operating costs per volume of aggregate heated.
- Reduces or eliminates the need for hot water for aggregate heating.
- Eliminates frozen materials.
- Eliminates the rusting of the plant through the use of steam and the related freeze/thaw problems.
- Optional cooling feature can provide up to a 25 degree F drop in concrete temperatures.
For a proposal on a system to meet your requirements please complete the Air Blast questionnaire (at the bottom of the page).
Q and A
Briefly, how does this system work?
A high volume centrifugal fan blows air across a natural gas or propane burner. The unit can either be mounted on a platform or on the ground. This heated air is ducted into the bottom of the aggregate bins. The type of air distribution is determined by the type of aggregate. The unit is capable of heating both coarse aggregate and the sand. Temperature sensors are installed to control the temperature of the aggregate. The system runs unattended.
How fast can the material be heated?
The material can be heated to required temperatures at rates up to 200 yards per hour.
Does this method produce hot spots?
No, the temperature of the air blowing on the stone can be regulated. The idea is to get large volumes of low temperature air through the aggregate.
Does this process dry out the material?
Heated dry air will dry out material. In the field we have tested the moisture drop over a one hour period to be minimal. We have also discovered that the moisture content becomes more consistent with this procedure.
Is this system noisy?
Our centrifugal fan sounds like a purr when compared to a screaming axial fan. This provides a safer working environment and less irritation to the workers.
What are the operating costs?
The operating costs will fluctuate depending on the cost of power, propane/natural gas, the mix design, the ambient temperature, etc. For example: In Farmington, New Mexico, the cost to heat 1800 lbs (the equivalent of one yard) of coarse stone 40˚F is about $0.28. This assumes $3.25 per million BTUS for natural gas and about $0.08 per KWH for the electricity to operate the blower. In Port Huron, Michigan, the cost to heat the same is about $0.56 per yard. Note: A 40˚F rise is stone temperature is equivalent to a 20˚F rise in final concrete temperature.
How long does it take to install?
We can install a typical system in 3 days. We also supply the necessary drawings and assistance should you decide to install the system with your own forces.
How soon can a unit be delivered?
We can usually deliver within 30 days from the date the order is placed.
What type of warranty is guaranteed with this unit?
We provide a one year all parts and labor warranty on all equipment delivered in the USA. We provide a one year parts only warranty on all equipment delivered outside of the USA.