Determining Appropriate Natural Caves for Underground Crude Oil Storage by Admixture FAHP and TOPSIS Methods

The world financial crisis has drastically raised the costs of hydrocarbon materials. This simply manifests the strategic significance of crude oil storage. Regarding the special rank of the oil in Iran’s economy، storage industry development can be one of the solutions to control such a crisis. Underground storage of crude oil in synthetic structures (rock caverns، salt caverns، and obsolete mines) and natural structures (depleted fields of oil and gas، underground water resources، and natural caves) is possible. Among these possibilities more adaptable to the environment is the most appropriate. Due to the existence of many caves in Iran، crude oils storage in natural caves is a proper option. It is clear that if natural caves are used instead of caverns، much can be saved. The present article intends to choose a proper cave for crude oil storage through studying the natural caves based on a combination of fuzzy analytical hierarchy process (FAHP) and technique for order performance by similarity to idea solution (TOPSIS). The likely option is chosen. Roudafshan Cave is considered appropriate for crude oil underground storage based on several qualitative and quantitative criteria including tourism and environment protection regulations، capacity، distance from both main pipes of crude oil transfer and country''s major petroleum factories. It should be noted that these criteria are ranked by an experienced team. This cave is located in the north east of Tehran in Firoozkooh and has three passageways which are among the largest ones in the country. Generally، its capacity is estimated to be about 250،000 square meters