Overview
A flue gas waste heat recovery heat exchanger turns the sensible heat in industrial exhaust gas into a usable heat source, normally hot water, hot air or steam. The recovery scheme has to be designed around both the heat demand and the flue gas side risks of dew point corrosion and fouling; otherwise a high-efficiency unit can have a short service life.
Features
- Water-cooled or air-cooled recovery scheme selected for the duty
- Fin material and fin spacing set by dew point corrosion and dust loading
- Can be combined with air preheaters and flue gas coolers
- Suitable for new projects and retrofit of existing systems
- Payback estimate available to support project decisions
Materials and specifications
| Recovery form | Flue gas to water (hot water), flue gas to air (hot air), steam generation |
| Tube material | Carbon steel high-frequency welded finned tube |
| Optional materials | ND steel, 316L stainless steel, enamel-coated finned tube |
| Key checks | Cold-end wall temperature, dew point corrosion, fouling and cleaning method |
| Design inputs | Flue gas flow and composition, inlet / outlet temperature, recovery medium and target parameters |
Typical applications
| Application | Description |
|---|---|
| Boiler exhaust | Recover stack heat for hot water or hot air. |
| Industrial kilns | High-temperature flue gas recovery. |
| Drying furnaces | Flue gas heat for drying air. |
| Metallurgy and building materials | Process waste heat recovery. |
| Existing systems | Add a heat exchanger to reduce site energy consumption. |
FAQ
Should I choose a water-cooled or air-cooled scheme?
It depends on how the recovered heat will be used. Choose water-cooled when hot water is needed and air-cooled when hot air is needed. If both are required, the two duties can be combined.
What payback period can be expected?
It depends on flue gas flow, recoverable heat and local energy prices. We calculate it for the specific duty and can provide a payback estimate.
Can it be added to an existing system?
Yes. A retrofit requires a check of flue gas pressure drop and available space. Send the system drawing and layout conditions.