Thermal Coating for Pentane tank– Oil & Gas Case Study
We worked with our sister company EnerTherm Ltd to develop a liquid thermal insulation system. The dual layer insulation system was proposed as a replacement for the aerogel blanket on a major US refinery pentane sphere. This system presents a seamless cover compared to traditional fibrous insulation and can protect against corrosion under insulation CUI. EnerTherm Engineering consultants investigated the potential of using such a system against condensation build-up at the surface of the coating and overall heat loss performance compared with the Aerogel blanket.
CFD was used to conduct scenario analysis and calculate the necessary thickness of the thermal coating to reduce the risk of condensation build-up at the surface of the insulated surface. Weather properties and patterns (temperature, relative humidity and wind speed) were used to evaluate seasonal changes.
With an internal temperature of –10oC for Pentane, the necessary thickness of liquid insulation with thermal conductivity of 0.046 W/m.K was 38 mm to match the heat loss value of the aerogel blanket.
After 6 months of running with the liquid insulation coating, the performance showed a significant reduction of 1.2oC compared to the Aerogel blanket. Outperforming traditional insulation was achieved by evaluating the optimum thickness of insulation as well as achieving a seamless insulating blanket.
A 3D model of the pentane tank was built with a steel shell (20mm) and varied thermal coating thicknesses.
Being a coastal application, various wind speeds, air velocities and levels of relative humidity in the air were modelled for the summer and winter seasons. Dew point formation and surface water condensation were computed across the entire surface. Optimum liquid insulation was calculated from this model and demonstrated clear feasibility.