Abstract

Salt caverns are increasingly considered for fluid storage in the Texas Gulf Coast. Types of fluids considered for salt cavern storage include: oil field wastes, natural gas, condensate, brine, and potentially hydrogen. Salt formations provide a temporary home for products needed for daily consumption. Salt caverns are stable with respect to injection and withdrawal cycles so they can accommodate a wide variety of energy resources. The storage capacity can be large enough for temporary storage, seasonal reserves, or strategic reserves. In this study, we present a high-level analysis of salt dome storage possibilities and analyze where the current storage activity is and its proximity to known CO₂ and H₂ pipeline infrastructure. We use publicly available data as well as data from the Bureau of Economic Geology.

Through fractionation of natural gas liquids and liquid petroleum gas, different products are stored underground for fuel and feedstock for power plants, refineries, homes, and businesses. Operators have to carefully monitor liquid saturation to prevent salt caverns increasing in size causing salt creep, cavern roof collapse, or uncontrolled leaching into water supplies.

Oil field wastes that are most troublesome to dispose of through regular class II injection are good candidates for salt caverns. There are three options for storing natural gas, condensate, brine, and potentially hydrogen in the United States. These include (1) depleted oil fields, (2) salt formations, and (3) depleted aquifers. Salt formations can either be deep and narrow or bedded making them wide and shallow. Depleted aquifers can be converted for storage of natural gas liquids by injection at high pressure, utilizing the permeable rock formations as overburden and the water of varying quality as containment.