Heat Loss from Oil Filled Tanks and Pipe Lines
Heat loss from insulated and non insulated sheltered and exposed oil tanks and pipes.
Heat loss from the oil in a storage tank or pipe line can be roughly estimated from the values below.
| Application | Temperature difference between Oil and ambient Air (oF) | Heat Transfer Rate - α - (Btu/(hr ft2 oF)) | |
|---|---|---|---|
| Without Insulation | Insulated | ||
| Sheltered tanks | - 50 | 1.2 | 0.3 |
| 50 - 80 | 1.3 | 0.33 | |
| 80 - 100 | 1.4 | 0.35 | |
| Exposed tanks | - 50 | 1.4 | 0.35 |
| 50 - 80 | 1.5 | 0.38 | |
| 80 - 100 | 1.6 | 0.4 | |
| Tank in Pit | All Temperatures | 1.2 | - |
| Sheltered Pipe Line | - 80 | 1.5 | 0.4 |
| 80 - 260 | 2.3 | 0.58 | |
| Exposed Pipe Line | - 80 | 1.8 | 0.45 |
| 80 - 260 | 2.75 | 0.7 | |
- 1 Btu/(hr ft2 oF) = 5.678 W/(m2 oC) = 4.882 kcal/(h m2 oC)
- T (oC) = 5/9 (T (oF) - 32)
The total heat loss from an application can be calculated as:
Q = α A dt (1)
where
Q = heat loss (W, Btu/hr)
α = heat transfer rate (W/(m2 oC), Btu/hr ft2 oF)
A = area (m2, ft2)
dt = temperature difference (oC, oF)
Example - Heat loss from an insulated exposed tank
An insulated exposed tank with outside area of 1000 ft2 contains oil at temperature 90 oF. The surrounding temperature is 31 oF. With temperature difference 68 oF (90 oF - 31 oF) - the Heat Transfer Rate (α) from the table above is aprox. 0.4 Btu/hr ft2 oF.
The heat loss from the oil tank can be estimated to:
Q = (0.4 Btu/hr ft2 oF) (1000 ft2) ((90 oF) - (32 oF))
= 23200 Btu/hr
