What Is Air Compressor Heat Recovery?
Heat recovery for air compressors captures waste heat generated during the compression process and repurposes it for useful applications like water heating or hot air for space heating. When air compressors operate, most of the energy consumption is converted into heat energy. A heat recovery system takes this excess heat from the compressor – also known as waste heat – and reuses it, significantly cutting energy costs.
A well-designed compressed air system allows companies to recover heat, turning this excess heat into usable energy for heating systems. This reduces reliance on external heating methods such as fuel oil or natural gas, offering financial and environmental benefits. Let us explore how heat recovery technology works in air compressor heat recovery systems.
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How Does Heat Recovery Work in Air Compressors?
Compressing air generates a large amount of exhaust heat. In fact, up to 94% of the total energy an air compressor uses can be converted into heat.
Heat Exchangers
Heat exchangers, such as plate and printed circuit heat exchangers (PCHEs), are key components that capture this compressed air heat.
Uses for Recovered Heat, Hot Water or Steam
The recovered hot air or heat from the compressor can then be transferred through water-cooled or air-based systems, making it available for various heating purposes.
There are two main compressed air heat recovery methods:
- Water-based systems that recover heat to warm process water for cleaning or other industrial needs.
- Air-based systems that redirect hot air to heat buildings or facilities.
By installing these systems, businesses can recover heat energy and convert it into useful energy for applications like water heating, reducing the need for other energy sources.
Key Components in Heat Recovery Systems
Air Compressor Heat Recovery is the process of capturing the hot air expelled during the compression phase and redirecting it to useful purposes, like heating hot water or providing space heating.
Main Components:
- Rotary Screw Compressors are popular for their efficiency and reliability in large-scale operations. They are ideal for air compressor heat recovery because they generate significant excess heat that can be easily captured.
- Heat Exchangers transfer heat from the compressor to process water or air. These systems help industrial manufacturers lower energy costs by reducing the need for additional heating sources.
Benefits of Using Heat Recovery for Air Compressors
- Energy Savings: companies can significantly reduce energy consumption by recovering heat from the compressor. For example, recovering heat from an air compressor for water heating can reduce energy costs for operations that require large amounts of hot water, such as in the food or manufacturing industries.
- Cost Reduction: using energy recovery from air compressors means less reliance on external heating systems, ultimately lowering utility bills and cutting the use of oil or gas.
- Sustainability: heat recovery helps reduce the overall carbon footprint by minimising the need for electrical energy and fuel-based heating systems. By using heat energy generated by the compressor, businesses contribute to greener, more sustainable operations.
- Process Optimisation: with heat recovery, businesses can operate more efficiently by reducing waste and using their energy better. For instance, Atlas Copco’s modern rotary screw compressors are designed with integrated heat recovery features that help maximise overall efficiency – and reduce energy consumed by air compressors.
How Much Can an Air Compressor Heat Recovery System Save?
In many cases, 50 – 94% of the waste heat from air compressors is recoverable. Here is what affects the savings:
- Larger or oil-free compressors generate more heat, which can be captured.
- Continuous running saves more than sporadic running.
- If you use heat for an industrial heating system or service water heating, the savings will vary based on how effectively the heat is utilised.
- Well-maintained systems with good recovery mechanisms will capture more heat.
In financial terms, you could save 10 – 30% on total energy costs for industrial operations. At Control Gear, we recommend a site assessment to get an accurate quote before deciding the best course of action.
Challenges in Heat Recovery Systems
While energy recovery systems offer clear benefits, there are also some challenges to consider:
Compatibility
Not all compressors are designed to work with heat recovery systems. It is important to select a compressor that is compatible with a heat exchanger system. Screw compressors, for example, may require special modifications or an integrated heat recovery solution to optimise performance.
Infrastructure Requirements
Retrofitting a system to accommodate heat recovery may require adjustments to existing infrastructure, such as installing new ductwork, plumbing, or electrical systems to support air heat recovery and water heating.
Temperature Mismatch
The temperature of the recovered heat must match the application’s needs. A heat recovery calculator can help determine if the system will provide enough heat for specific processes, such as air for space or process water heating.
Maintenance
Regular maintenance of steel plate heat exchangers is necessary to ensure the system remains efficient. Dirt buildup or wear and tear can affect heat transfer efficiency, reducing the system’s overall benefits.
How to Maximise the Efficiency of Your Heat Recovery System
To ensure your heat recovery system operates efficiently, consider the following steps:
- Select the Right Equipment: choose compressors that are designed for heat recovery, such as models with integrated heat recovery options from Control Gear and Atlas Copco UK.
- Optimise Heat Exchangers: use high-quality heat exchangers to minimise heat loss during transfer. Water-cooled and well-maintained air-based systems will help capture and use as much excess heat as possible.
- Conduct Regular Audits: use a heat recovery calculator to evaluate your system’s performance and ensure it meets your energy and heating requirements. Regular energy audits can also help you identify areas for improvement.
- Maintain the System: professional maintenance, such as cleaning and checking components like heat exchangers and oil coolers, will ensure the system continues to work efficiently over time. This will help recover heat without performance issues and comply with carbon emissions and energy consumption targets.
Compressed Air Heat Recovery – the Next Step
Heat recovery for air compressors is a powerful tool for improving energy efficiency and reducing operational costs. By using air compressor heat recovery systems and optimising heat exchangers, businesses can repurpose waste heat for useful applications, such as space or process heating, reducing overall energy consumed.
At Control Gear, we specialise in providing solutions that maximise energy savings through effective recyclable heat strategies. Whether you are interested in compressor heat recovery for water heating or exploring options for air heat recovery, our team can help you implement the right system for your needs.
Ready to reduce energy consumption and lower energy costs? Contact Control Gear today to learn how we can help you make the most of your compressed air system with heat recovery solutions.