Martin Løvland explains the principles of heating oil in storage tanks.

Parat Halvorsen has gathered key personnel from the maritime industry to a technical review and discussion of tank heating solutions for supply vessels with NOFO notation. Shipowners, consultants, technical and operational persons from shipyards, and the NCA (Norwegian Coastal Administration) were present, and practical tests were performed at the company fabrication and test facilities in Flekkefjord.

The seminar also covered the basic background theories for the empirical tests, one important aspect being that oil has less than 20% of the thermal conductivity of water. In addition the oil has a much higher viscosity which increases the conductivity gap even more.

Parat has over the last five years had great success delivering its OSR system based on steam injection into the oil storage tanks. Lately, alternative solutions based on tank heating with low temperature compact heating coils have come on the market. To verify if this hot water based solution can work, Parat has installed one compact heating coil and one steam injection nozzle into a test-tank filled with heavy oil.

The results from the tests clearly showed the participants that use of a heating coil for increasing the viscosity of the oil is not a viable solution and that the theoretical conclusions match the empirical results.

After testing with the hot water coil was concluded, Parat started up the steam injection system and the participants were then able to witness through live temperature logging that the oil was evenly heated in a matter of minutes. To Parat’s own knowledge and based on information from NOFO the hot water coil system has up until now only been tested in water. The empirical data from the tests performed in heavy oil clearly show that the output from the hot water coil is only around 10% of the output measured using the same coil in water.

"Parat Halvorsen hope that by performing this test we have contributed to increasing the competence in the market and that for future projects for vessels that shall have oil recovery capabilities, solutions that actually work in a live situation with oil spill on water will be selected." Yngve M. Halvorsen, CEO Parat Halvorsen AS.