After heating the oil with heat transfer oil, is it necessary to close the vent valves of the low-level tank and the high-level tank?
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After heating the oil with heat transfer oil, is it necessary to close the vent valves of the low-level tank and the high-level tank?
The heating process of heat transfer oil mainly involves the removal of water. After dehydration is completed, during normal operation, the low-level and high-level tanks are generally sealed with nitrogen, and a pressure control valve assembly is used to maintain the nitrogen pressure in the gas space, thereby reducing the decomposition and aging of the heat transfer oil.
It’s an open system; there’s no need to turn it off, as doing so would cause serious problems.
Some process units require heat supply and heat tracing systems using heat transfer oil at multiple temperature levels, yet they do not want to use heat transfer oil of two different specifications. In order to maintain a low viscosity of the heat transfer oil at lower temperature levels, it is necessary to choose heat transfer oil with a vapor pressure of several dozen kPaG or even over 1 barg at higher temperature levels. The entire hot oil system is designed as a closed system that operates under pressure; the sump operates under a nitrogen blanket at several bargs of pressure. Operating under pressure also increases the risk of leakage and spontaneous ignition of the high-temperature heat transfer oil.
What we need here is a heat transfer oil system for heating and heat tracing, with multiple temperature levels, and the outlet temperature is set at 140–150 degrees