Reclaiming Every BTU: The Ultimate Guide to Industrial Waste Heat Recovery
Industrial facilities release significant amounts of recoverable waste heat every day—energy that was purchased but not productively used. Much of it is lost through hot exhaust streams, representing major opportunities for industrial operations to implement waste heat recovery systems.
At Sigma Thermal, our advanced waste heat recovery systems capture the thermal energy, transfer it to where it is needed, and reuse it as opposed to simply releasing it into the atmosphere. Recovering this otherwise lost energy allows facilities to reduce operating costs and improve efficiency while supporting environmental goals. As energy prices continue to rise, implementing waste heat recovery has become a strategic and financially sound investment.
What Is Waste Heat and Where Can It Be Found?
Industrial processes produce substantial heat, but a significant portion escapes through stacks, vents, cooling water, and blowdown. Any process that burns fuel, compresses air, oxidizes VOCs, or dries product and reaches at least 450 °F is a good candidate for waste heat recovery.
Common Waste Heat Producers
- Thermal oxidizers. Used to destroy VOCs, thermal oxidizers release high-temperature exhaust streams that are ideal for waste heat recovery.
- Combustion turbines. Combustion turbines generate hot gas, often over 900 °F, that can be repurposed.
- Fired heaters. These are commonly found in oil, gas, and chemical manufacturing. The flue gases they expel are prime heat recovery candidates.
- Kilns. Cement, lime, and mineral processing kilns release high volumes of hot exhaust.
- Dryers. Industrial drying systems often vent substantial amounts of thermal energy in their process air.
- Blast furnaces. Steel production involves extreme temperatures, with exhaust heat that can be captured and redirected.
- Engine and turbine exhaust. Engines used for power generation or compression emit consistent high-temperature heat.
- Steam system exhaust/blowdown. Boiler blowdown contains high-pressure, high-temperature flash steam that can be recovered.
Technologies for Waste Heat Recovery
Understanding how waste heat recovery works involves knowing the right system to capture it and directing it to a process that can use that heat. At Sigma Thermal, our engineers design and build the following types of waste heat technologies.
Combustion Air Pre-Heat (CAPH) Systems
CAPH systems use heater exhaust gases to pre-heat incoming combustion air. Combustion air burns better at higher temperatures, and plants can see system efficiency increase to 90%.
Waste Heat-Powered Thermal Fluid Heating Systems
Using thermal oil, water, or glycol, these closed-loop systems capture thermal energy from waste heat producers and deliver it wherever your process needs it. Our heat exchanger heat recovery design keeps the transfer reliable and efficient, even over long distances.
High Particulate Systems
Particulate-rich exhaust from biomass systems requires robust, specialized heat exchangers. Sigma Thermal specializes in biomass and gasification systems for oil, gas, and chemical plants, and can capture waste heat from high-particulate exhaust gas. Once recovered, this thermal energy can be used with any waste heat consumer.
Common Waste Heat Consumers
Recovered heat can be used almost anywhere thermal energy is needed:
- Combustion air pre-heating
- Boiler feedwater heating
- ORC generators for on-site electricity
- Building HVAC systems
- Wash water pre-heating
- General process heat (tank heating, heat exchangers, thermal fluid heaters)
Sigma Thermal: Your Partner in Energy Efficiency
Industrial waste heat recovery is one of the most effective ways to reduce annual fuel usage and advance sustainability goals. When combined with available federal and state tax incentives, industrial waste heat recovery systems can save facilities a significant amount of money and improve ROI.
If your facility is ready to make waste heat recovery part of its long-term strategy, Sigma Thermal is your partner. Our engineers are experts in heat energy management, and we offer hands-on services ranging from audits to detailed technical evaluations. We supply the right equipment to guarantee maximum energy savings.
Contact us today or request a quote to get started on your waste heat recovery project.
