Air cooling compressor and water cooling compressor, as the two most widely used types of air compressors, have different cooling systems.
There are significant differences in production processes, cooling methods, cooling efficiency and applications. So how do we choose?
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What Is the Air Cooling Compressor?
The air cooling compressor is a type of air compressor that utilizes ambient air as its cooling medium, dissipating the heat generated during the process of air compression.
Air Cooled Compressor Working Principle
When air is compressed by the screw (in rotary screw compressor) or crankshaft (in piston compressor), it naturally generates heat — the air molecules become agitated due to the increase in pressure and consequently, release energy in the form of heat.
An air-cooled compressor is equipped with the cooling fan that handles this generated heat. When the compressor is operational, this fan kicks into action as well, driving cool ambient air across the compressor — specifically parts like the cylinder and heads.
The flowing cool air absorbs the heat from the compressor, taking it away and distributing it into the surrounding atmosphere. So that the compressor does not overheat and functions efficiently, maintaining the stability of the compressor, and ultimately prolonging its lifespan.
In essence, an air-cooled compressor works by harnessing the readily available air around it, using it to keep temperatures in check, and enable smooth and safe operations.
What Is the Water Cooling Compressor?
The water cooling compressor is a type of air compressor that utilizes water for its cooling process, working to dissipate the heat generated during the compression of air.
Water Cooled Compressor Working Principle
Like every other type, a water-cooled compressor generates heat as it compresses air. The way it handles heat is by moving water away from air compressor.
In a water cooling compressor, the network of water-filled tubes or jackets is incorporated into the compressor system. This network of water pathways envelopes heat-generating components, such as the cylinder, and aligns purposefully with the working path.
As the compressor functions and heat builds, circulating water in these jackets absorbs this heat. The heated water then flows away from the compressor, taking the absorbed heat with it, to a radiator or heat exchanger where it is cooled down. Cooled water is then reintroduced back into the compressor casing, completing a cooling loop.
This cycling of water offers a robust approach to maintain temperatures, ensuring the compressor doesn’t overheat and can operate continuously. It further increases efficiency by capturing and repurposing part of the energy released during compression.
Simply put, water-cooled compressors operate by utilizing water’s excellent heat absorption capabilities to effectively manage heat, thus championing operations where high-duty, continuous functioning is required.
Air Cooling Compressor VS Water Cooling Compressor
Cooling Efficiency
Water cooling compressors generally have higher cooling efficiency than air-cooled air compressors. Water coolers provide better heat transfer and dissipation, cooling hot compressed air to a lower temperature.
In contrast, air coolers rely on convection heat dissipation from the surrounding air, and their cooling effect is relatively low.
There are two points to note here:
- The climate can influence the effectiveness of air-cooled systems. In cooler environments, air-cooled compressors can perform quite efficiently.
- In the water-cooling system, after long-term operation, chemical reactions and scaling occur in the calcium and magnesium ions in the water, thus affecting the cooling efficiency.
Temperature Control
Water cooling compressors have better temperature control capabilities. Because water coolers can provide higher cooling efficiency, the operating temperature of the air compressor can be controlled more effectively.
This helps maintain stable operating conditions and extend equipment life.
Noise Level
Water cooling compressors are generally quieter than air-cooled air compressors. When the air cooling system is working, the noise generated by the rotation of the fan blades is significantly higher than that of the water cooling system.
Production costs
The air cooling compressor has lower production and procurement costs. Under the same power and working pressure, the cost of a water-cooled compressor is about 10% higher than that of an air-cooled compressor.
Installation and maintenance
Water cooling compressors can be more complex to install and maintain. The water cooling system requires the installation of additional equipment such as water pumps, water pipes, and cooling towers, and the quality of the cooling water needs to be checked and maintained regularly.
In contrast, air-cooled air compressors are relatively simple to install and maintain and do not require additional water cooling systems.
Airpressa recommends that if the air cooling compressor is installed in a dusty and closed environment, a good ventilation system is one of the options you should consider.
Space Requirements
Air-cooled compressors typically need more space owing to the need for adequate ventilation, something water-cooled compressors don’t require.
On the flip side, the latter’s additional cooling infrastructure like cooling towers might also necessitate extra space, though typically outside the compressor room.
Environmental impact
Water cooling compressors have a lower environmental impact in terms of heat emissions than air-cooled air compressors.
Air coolers dissipate heat directly into the surrounding air, potentially causing thermal pollution. The water cooler transfers heat to the water in the environment through equipment such as cooling towers, which has less impact on the environment.
Therefore, if there is a lot of dust in the working environment, such as textile, spraying, titanium powder, etc., water-cooled compressor is a better choice.
However, the water cooling systems require a consistent water supply, which can be a limiting factor in areas experiencing water scarcity. Also, they could lead to extensive water usage, which might not be environmentally favorable despite their lower heat emissions.
Should I Choose Air Cooling Compressor or Water Cooling?
When mulling over the decision between an air-cooled and water-cooled compressor, prioritizing your requirements based on various factors will enable you to choose the most suitable unit. Here are some key factors to consider:
1. Purchase Cost
As mentioned above, the purchase cost of air-cooling compressors is slightly lower than that of water-cooling compressors at the same quality level.
2. Climate and Environment
If the climate in your region is typically warm, water-cooled compressors might be better since they are highly efficient at dissipating heat.
For cooler climates, air-cooled ones could be more effective and economical.
3. Water Availability
Water-cooled units need a consistent water supply. If you’re situated in an area with limited water accessibility or strict water usage restrictions, air-cooled compressors might be a viable choice.
4. Operational Noise
Water-cooled compressors tend to run more quietly than their air-cooled counterparts. If your operations are in a noise-sensitive area, you may want to consider this aspect.
5. Space Constraints
Air-cooled units generally require proper ventilation and more space, while water-cooled ones can operate efficiently in a more compact area.
The extra infrastructure required for the water-cooled compressor, like pipes and potentially a cooling tower, could, however, increase the overall space requirement.
If your facility already has a cooling water system in place, implementing a water-cooled compressor could be more practical.
6. Maintenance and Setup Complexity
Air-cooled compressors are typically easier to install and maintain. Water-cooled compressors might require more complex piping arrangements and regular monitoring of water quality.
7. Energy Efficiency
Over the long term, the higher energy efficiency of a water-cooled compressor could result in significant cost savings, despite the potentially higher upfront costs.
8. Environmental Impact
Consider the potential impact of heat discharged into the environment from an air-cooled compressor. Water-cooled compressors tend to have a lesser impact in this regard, but their water usage might raise other environmental concerns.
By taking these factors into account, you can choose a compressor that best pertains to your specific needs and circumstances.