SOLUBILITIES OF LONG-CHAIN HYDROCARBONS IN CARBON-DIOXIDE

Heavy hydrocarbons are becoming an increasingly important problem for the natural gas industry as it develops more costly gas reserves, such as those in the deep Gulf of Mexico. The waxy substances precipiate d uring natural gas processing, causing blockage of transmission pipelin es. Knowledge of the solubility behavior of these hydrocarbon solids i s therefore necessary to develop solutions to the solid deposition pro blem. This work reports solid-supercritical fluid equilibrum data for long-chain n-alkanes in carbon dioxide, a component of natural gas, ov er a range of temperatures and pressures that are typical of natural g as processing. A flow apparatus was used to measure the solubility, an d the data were correlated by the Patel-Teja equation of state. Satisf actory agreement was obtained between calculated and experimental valu es, so the equation of state may be used to estimate the conditions fo r solid deposition and the amounts of solids formed at typical process ing conditions.