What are oil-free refinery compressors?
Oil-free compressors are specially designed for applications where the purity of air compression is needed. An oil-free compressor refers only to the compression chamber, not the compressor system as a whole or the resulting compressed air quality.
If a refinery application needs a compression that, despite harsh working environments, offers you reliability and efficiency, an oil-free screw compressor could be a better option.
And If energy consumption is a key necessity, you might opt for an oil-free tooth compressor because of its symmetrical, dynamically balanced rotor with more powerful oil-free compression.
Why oil-free compressor?
Compressed air is almost as pleasant as their innocence. If the process is exposed to oil, keeping air clean is more difficult, particularly when you use more and more oxygen, raising the costs you’ll face.
Many companies are turning to oil-free or oilless air compressors to address this concern. Oil-free compressors are becoming more popular today as they give savings on costs. Main reasons why the oil-free compressor are used:
There’s no need to collect or dispose of oil-ladened condensate
Downstream filters have limited need for repair, as they don’t filter gasoline.
Reduced oil costs, because there’s no need to continually refill your compressor
The amount of electricity is reduced since certain fluid-flooded systems do not need to increase the pressure due to filtration.
These units will usually unload within two seconds of the unload order, and can use around 18 per cent of their full load horsepower when unloaded.
How oil-free compressor works?
1. Air inlet:
Oil-less air compressors begin by taking in outside air through their unloader valve and going via an inlet air filter (or filters) to ensure clean air. The filter will minimize damage to your compressor and its components within it. These filters are typically fine enough that they keep out dust, dirt and small debris.
The unloader valve opens, positioning it in the “hot” position, to help the compressor pump air into its chamber. When the valve is closed the compressor enters the condition “unloaded” and starts running.
2. First Compressor Element:
The average compressor element will operate at about 2.5 bar, and the unit can operate at a temperature of up to 180 degrees by compressing air alone. This can be more than twice as high as the temperature achieved by oil-lubricated compressors due to the absence of a moving medium to absorb heat.
3. Intercooler Access:
Compressing air generates heat which limits the air’s oxygen content and therefore reduces its density. The cooling of the air essentially serves as a simple method for the engine to reuse denser and more oxygen-rich air, which in turn provides more fuel and improves power output when the air compressor works with a combustion engine.
There are two reasons why Intercoolers are important. Secondly, they cool down the air to a suitable temperature to mitigate the possibility of any heat-related effects. Second, in two-stage pumps, intercoolers allow air to be compressed at much higher PSIs, and the cooling cycle ensures less wear is encountered in the second stage.
4. Aftercooler Access:
The air will reach temperatures of around 150 degrees during its second compression phase which will require additional cooling before it can be used in other equipment. After the final stages of compression, the aftercooler becomes the outlet for cold, and this cooling allows for proper storage.
5. Pressure Switches:
Detection equipment will monitor the level of air you have in your air compressor tank. If it falls below a specified level, the air compressor switches back on and starts working to rebuild the tank’s pressurized air. The pressure control is the one used to track and turn off and on the compressor.