Petroleum products such as propane, butane, liquified propane gas, and liquified natural gas are unloaded from ship carriers through pipelines to storage facilities located 10-12 kms inland. This process is an energy intensive and a time-consuming operation. Unloading at high flow rates results in excessive boil-off gas (BOG) generation in the storage tank thereby resulting in increased cost of pumping the fluid and increased cost of compressing the resulting BOG. If the BOG generated exceeds the capacity of the compressors, then the excess gas has to be flared resulting in loss of valuable raw material, besides the associated environmental damage. But, when low unloading flow rates are employed, it results in longer berthing time of the ship to unload the product thus incurring demurrage. In this paper, efficient ways to minimize the total cost of an unloading operation are explored by solving a generalized simulation optimization model and the results are discussed. The strategies and the results presented in this work are valuable for industrial applications.