Therminol® 55 Heat Transfer Fluid
Description
Therminol 55 is a synthetic heat transfer fluid used in moderate-temperature applications. Therminol 55 fluid is designed for use in nonpressurized/low-pressure, indirect heating systems. It provides efficient, dependable, uniform process heat with no need for high pressures.
- Excellent resistance to fouling— Therminol 55 is a synthetic fluid, it prevents the effects of oxidation 10 times better than mineral oils, meaning less oxidation and solids formation. For systems without nitrogen inerting, the performance advantages are significant.
- Long Life—You will get years of reliable, cost-effective performance, even when operating your system continuously at 300°C (570°F). This means you do not have to over-specify your fluid.
- Excellent Low Temperature Pumpability—Therminol 55 is still pumpable at –28°C (–18°F), compared to some mineral oils that will not pump at temperatures below –7°C (20°F). With Therminol 55, your heat transfer fluid system can start up quickly and easily.
Typical Properties
| Property | Test Method | Typical Value, Units |
| Appearance | Clear yellow liquid | |
| Composition | Synthetic hydrocarbon mixture | |
| Maximum bulk temperature | 300 °C (570 °F) | |
| Extended maximum use temperature | 315 ºC (600 ºF) | |
| Maximum Film Temperature | 335 °C (635 °F) | |
| Normal Boiling Point | 351 °C (664 °F) | |
| Pumpability @ 300 mm2/s (cSt) @ 2000 mm2/s (cSt) | -8 °C (17 °F) -28 °C (-18 °F) | |
| Autoignition Temperature | ASTM E659 DIN 51794 | 343 °C (650 °F) 366 ºC (691 ºF) |
| Flash Point COC | ASTM D92 | 177 °C (350 °F) |
| Pour Point | ISO 3016 | -54 °C (-65 °F) |
| Minimum liquid temperatures for fully developed turbulent flow (NRe > 10000) 10 ft/s, 1-in. tube (3.048 m/s, 2.54-cm tube) 20 ft/s, 1-in. tube (6.096 m/s, 2.54-cm tube) | 67 °C (152 °F) 45 °C (114 °F) | |
| Minimum liquid temperatures for transitional region flow, (NRe > 2000) 10 ft/s, 1-in. tube (3.048 m/s, 2.54-cm tube) 20 ft/s, 1-in. tube (6.096 m/s, 2.54-cm tube) | 24 °C (75 °F) 11 °C (52 °F) | |
| Viscosity, Kinematic @ 100ºC @ 40ºC | ASTM D 445 ASTM D 445 | 3.52 cSt, mm2/s 19 cSt, mm2/s |
| Liquid Density @ 25ºC | ASTM D 4052 | 868 kg/m3 (7.25 lb/gal) |
| Heat of Vaporizationa | 228 kJ/kg (98.1 Btu/lb) | |
| Pseudocritical temperature | 512 °C (953 °F) | |
| Pseudocritical pressure | 13.2 bar (191 psia) | |
| Pseudocritical density | 258 kg/m3 (16.1 lb/ft3) | |
| Molecular Weight (Average) | 320 | |
| Moisture Content, maximum | ASTM E-203 | 150 ppm |
| Dielectric Constant @ 23°C | ASTM D-924 | 2.23 |
| Copper Corrosion | ASTM D 130 | <<1a |
Key Attributes
- Excellent resistance to fouling
- Excellent low temperature pumpability
- Lasting life
Applications
- htf – production of bioalcohol
- htf – production of biodiesel
- Asphalt
- Asphalt storage
- Biomass – orc
- Cement – waste heat recovery + orc
- Desalination
- Gas to liquid (gtl)
- Hot mix asphalt
- Natural gas purification
- Oil or gas processing
- Oil recycling
- Polymer & plastic
- Waste heat recover + orc
- Wood panels
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