Heat exchangers

Heat exchangers are often a critical part of an air treatment system. They can be used to cool process gases before treatment, recover valuable energy from exhaust streams, or provide heat for other process steps.

In many cases, a properly designed heat exchanger can significantly reduce operating costs while improving the performance of downstream equipment.

At PCA Air, we design and supply heat exchanger solutions for industrial air treatment, process cooling and energy recovery applications. Each system is selected based on the process conditions, required temperatures, available utilities and expected return on investment.

When to use?

When to use a heat exchanger?

Many air treatment technologies operate best within a specific temperature range.

Examples include:

Activated carbon systems typically require low inlet temperatures.
Biological treatment systems perform best at moderate temperatures.
Scrubbers often benefit from cooling to improve pollutant removal efficiency.
Thermal oxidizers can provide valuable waste heat that can be recovered elsewhere in the process.

When the process gas is too hot, a heat exchanger allows the temperature to be reduced without increasing airflow, consuming large quantities of water, or negatively impacting downstream treatment equipment.

Cooling process air

Cooling is one of the most common applications of industrial heat exchangers.

Compared to alternatives such as dilution or quenching, heat exchangers offer several advantages:

No increase in airflow volume.
Reduced load on downstream equipment.
Lower utility consumption.
Possibility to recover useful energy.
Better conditions for carbon adsorption and biological treatment.

Where deeper cooling is required, heat exchangers can be combined with chillers and refrigeration systems to achieve the desired outlet temperature.

Heat recovery

Many industrial exhaust streams contain significant amounts of recoverable energy.

Examples include:

Drying ovens
Thermal oxidizers
Process ventilation systems
Hot process exhausts

Rather than dissipating this energy to atmosphere, it can often be used to produce:

Hot air
Hot water
Steam
Thermal oil

Recovering process heat can significantly improve overall plant efficiency and reduce operating costs.

Which heat exchanger is right for the application?

There is no universal heat exchanger suitable for every application.

The optimal design depends on:

Gas composition
Temperature
Pressure
Required thermal duty
Fouling potential
Corrosion risk
Available utilities

Depending on the application, PCA Air can provide:

Shell-and-tube heat exchangers
Plate heat exchangers
Plate-and-shell heat exchangers
Tube-in-tube heat exchangers
Dimple plate heat exchangers
Custom-engineered solutions

The objective is always the same: achieve the required heat transfer while maintaining reliability and minimizing total lifecycle cost.

Materials of Construction

Material selection is often as important as thermal design.

As process gases are cooled, condensation may occur. If the gas contains acid gases, solvents or other corrosive compounds, material selection becomes critical for long-term reliability.

Depending on the application, heat exchangers may be constructed from:

SS304 ● SS316L ● SS310 ● 904L ● Duplex stainless steels ● Hastelloy ● Alloy 59 ● Other corrosion-resistant materials

Our engineers evaluate both process conditions and corrosion risks to ensure a suitable design.

Frequently asked questions about heat exchangers

Which air treatment systems benefit from gas cooling?

Many technologies have preferred operating temperature ranges, including:

Activated carbon adsorption systems
Biological air treatment systems
Wet scrubbers
VOC recovery systems

Cooling the gas before treatment can improve both efficiency and equipment lifetime.

Why use a heat exchanger instead of dilution air?

Dilution reduces gas temperature by adding ambient air, but it also increases airflow volume. This can lead to:

Larger ducting
Larger fans
Larger treatment equipment
Higher energy consumption

A heat exchanger lowers the temperature without increasing airflow, often resulting in a more compact and efficient system.

When should a heat exchanger be considered?

A heat exchanger is often worth considering when:

Process gases are too hot for downstream equipment.
Energy consumption needs to be reduced.
Recoverable waste heat is available.
Water consumption from quenching should be minimized.
Dilution air would result in excessive airflow increases.
Energy recovery can improve project economics.

What is the purpose of a heat exchanger in an air treatment system?

Heat exchangers transfer thermal energy from one process stream to another. In air treatment applications, they are commonly used to cool hot process gases before treatment, recover energy from exhaust streams, or provide heat for other process operations. Properly applied, they can reduce operating costs and improve the performance of downstream equipment.

Contact us

Have a question or need expert air purification advice?
Fill out the form below and our team will get back to you shortly.