Insulate oil tank in the tank farm. As compared to an uninsulated tank, a well insulated tank reduced the radiation loss to one thirds!
In the case furnace oil fired boilers, the furnace oil needs to be stored for future consumption. These tanks are called bulk oil tanks. At ambient temperatures, furnace oil is very viscous and it is difficult to pump it. Hence it is usually stored at a temperature of 60 degC and while transporting to boiler house its temperature is raised to 80 degC.
These bulk oil tanks are steam heated via a bottom coil to maintain a temperature of 60 degC in the tank. This oil is further heated via exit flow heaters to about 80 degC before being pumped to boiler house. In the absence of exit flow heaters, a temperature of 80 degC is maintained in the tank itself.
It is recommended to insulate the tanks in the tank farms. This is because it holds heated fluids in them.
Consider a 20KL furnace oil tank in which oil is heated to 60 degC via steam heating and stored. Thus,
*FO GCV 10200 kcal, 24 hr operation for 330 days in a year.
As can be seen, insulating the tank reduces the heat loss by more than 1/3rd ! Most tank farms would have 2 or more tanks and thus with uninsulated tanks, the losses multiply.