Recovering residual heat
The glass tube heat exchanger is installed downstream to use further residual heat in the flue gas.
Glass tube heat exchangers
A glass tube heat exchanger recovers further residual heat from flue gas, even where the acid dew point may be undershot. The heating surfaces are acid-resistant borosilicate glass, steel parts in contact with flue gas are PTFE-coated and the glass tubes are sealed with PTFE. Because of these materials, the heat-emitting medium is limited to 260 °C.
Discover the technology
The material makes the difference.
Borosilicate glass forms the heating surfaces. Steel parts in contact with flue gas are PTFE-coated, and the glass tubes are sealed with PTFE seals.
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Glass tube heat exchangers: modular in structure, individually designed.
Material, media and structure determine the specific design.
Using borosilicate glass
The heating surfaces are made of acid-resistant borosilicate glass. It is suited to applications where the flue gas may fall below the acid dew point.
Protecting steel parts and seals
Steel parts in contact with flue gas are PTFE-coated; the individual glass tubes are sealed with PTFE seals.
Glass tube heat exchangers at a glance.
Material and media determine the design.
| Product | Design | Application | Details |
|---|---|---|---|
| Glass tube heat exchanger | Borosilicate glass | Heat recovery with heating surfaces made of borosilicate glass. | View details |
Finned plate or glass tube?
The glass tube heat exchanger is installed downstream when further residual heat is to be extracted from the flue gas. The suitability of both designs is checked against the media and operating conditions.
| Finned plate heat exchanger | Glass tube heat exchanger | |
|---|---|---|
| Heating surface | Cast-iron finned plates, up to 68 m²/m³ | Borosilicate glass tubes |
| Heat-emitting medium | Max. 680 °C | Max. 260 °C |
| Task | Transfer heat between gaseous media, e.g. flue gas to air | Recover residual heat from flue gas, also below the acid dew point |
| Corrosion protection | Cast iron, resistant to corrosion and erosion | Acid-resistant glass, PTFE-coated steel parts, PTFE seals |
Glass tube heat exchangers in detail.
Glass tube heat exchanger
Heat recovery with heating surfaces made of borosilicate glass.
- Heating surfaces
- Borosilicate glass
- Steel protection
- PTFE coating on parts in contact with flue gas
- Sealing
- PTFE seals
- Heat-emitting medium
- Max. 260 °C
When further residual heat is extracted from the flue gas, the temperature may fall below the acid dew point. For this application, a glass tube heat exchanger is installed downstream.
The combination of borosilicate glass, PTFE-coated steel parts and PTFE seals provides corrosion protection. Actual suitability must be confirmed on the basis of the media composition and operating conditions.
Because of the materials used, the temperature of the heat-emitting medium is limited to 260 °C. This does not imply a general guarantee of the operating limits of every plant.
Technical documents.
Recuperative heat exchangers
Ask Kablitz for the technical documents relevant to your product and application.
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Which conditions matter with corrosive flue gas?
Suitability depends on the media, dew point and operating conditions. Borosilicate glass heating surfaces and protected steel parts are intended for heat recovery under corrosive conditions. The materials alone do not establish suitability for every flue gas or temperature. Provide the known flue gas composition and inlet and outlet temperatures for project-specific assessment.
Cast-iron finned plate heat exchangersWhich data helps with system design?
Useful data includes flue gas and air flow rates, inlet and outlet temperatures, operating pressure and allowable pressure losses. Where known, describe flue gas composition, dew point and available installation space.
Can I inquire without complete design data?
Yes. Technical checklist fields are optional: provide the data you already know and leave outstanding points for further discussion.
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