Economizers for industrial heat recovery

Higher efficiency, lower fuel consumption, reduced emissions

Economizers have long been key components of modern industrial heating and combustion systems. They utilize the residual heat contained in exhaust and flue gases, and other exhaust air streams to preheat thermal oil, boiler feedwater or other operating and process media. This can significantly increase the overall efficiency of the system, while simultaneously reducing fuel consumption and thus, operating costs as well as emissions. CAW develops robust economizers for demanding industrial applications – designed for high gas temperatures, aggressive media and long operating times.

Our economizers are individually customized to the respective heating, combustion, and process systems and can be integrated into new construction projects as well as retrofitted into existing systems.

How does an economizer work?

An economizer is a heat exchanger that utilizes as much of the residual heat as possible, primarily from exhaust gas streams from combustion systems, incinerators or exhaust air streams from other process and production facilities, to preheat another medium. Heat transfer occurs indirectly, without mixing the primary and secondary media.

Design and process steps

Exhaust air / flue gas side: Depending on their volume, temperature, and constituents, such as ash or fly ash, hot gases flow through or around the heating surfaces of the economizer.
Media side: At the same time, another medium such as e.g., thermal oil, boiler feedwater or process air, absorbs the recovered heat.
Heat transfer: The thermal energy is transferred via specially designed heating surfaces.
Recirculation: Depending on the energy content and temperature level, the recovered energy is fed back to the heating / combustion system or the downstream process.

Technical features of the CAW economiser

Designed for a wide range of flue gas temperatures and varying loads.
High heat transfer efficiency combined with a compact design.
Material selection tailored to media temperatures, flue gas / exhaust air compositions, susceptibility to corrosion, and degree of fouling.
Low pressure drops on both media sides of the heat exchanger.
Design as smooth or finned-tube heating bundle, or as custom heat exchanger.

Where are economizers used?

Economizers are used wherever exhaust gas streams with suitable temperatures and economically viable heat potential arise but have not yet been utilized. CAW integrates economizers seamlessly into a wide variety of plant designs.

Typical system types and applications

Steam boiler systems

Preheating boilerfeed water to reduce fuel consumption.

Thermal oil systems

Recovery of exhaust heat to support oil heating by raising the thermal oil return temperature.

Thermal oxidizers

Heat recovery from thermal exhaust air purification.

Waste heat recovery systems

Integration into complex heat recovery concepts.

Use as a component of efficient energy systems

Increase in the overall efficiency of existing plants.
Reduction in fuel consumption and operating costs.
Reduction in CO2 and other pollutant emissions.
Improved cost-effectiveness due to short payback periods.

Industries in which economizers are used

Economizers can be used across a wide range of industries and are particularly well-suited for industries with continuous combustion or high-temperature processes.