Arab J Sci Eng (2014) 39:8341–8346 DOI 10.1007/s13369-014-1355-5 RESEARCH ARTICLE - PETROLEUM ENGINEERING A New Correlation to Predict Dew Point Pressure in Wet Gas Reservoirs Ehsan Ghanaatpisheh · Hosein Vahdani · Kamal Bolandparvaz Jahromi Received: 26 June 2013 / Accepted: 31 January 2014 / Published online: 13 September 2014 © King Fahd University of Petroleum and Minerals 2014 Abstract Correlations and equation of state (EOS) are two important tools for dew point pressure calculation. Several correlations introduced for gas condensate reservoirs, these correlations have limited range of use, and they could not be applied for wet gas reservoirs. Although EOS is more general, but sometimes dew point pressure could not be cal- culated from EOS (i.e., when limited range of components are available). So a new correlation is needed to calculate dew point pressure for wet gas reservoirs (47749 < GOR < 231708 scf/STB) when limited range of component (i.e., up to C 7+ fraction) is available. A total of 114 samples from wet gas fields of south west of Iran are used to generate a corre- lation. The new correlation has an average relative deviation (ARD) of -0.15 % and average absolute deviation (AAD) of 2.28 %. The accuracy of the correlation has been compared with Soave–Redlich–Kwong and Peng–Robinson equations of states and available correlations in the literature. In some cases, it is not possible to calculate dew point pressure with regard to equation of states; moreover, gas condensate corre- lations available in literature are applicable for limited range of data. As a result, it is shown that for this range of data, the presented new correlation outperforms equations of state and gas condensate correlations available in literature. Keywords Correlation · Dew point pressure · Wet gas · Equation of state E. Ghanaatpisheh (B ) · H. Vahdani · K. Bolandparvaz Jahromi National Iran Oil Company (South Zagros Oil and Gas Production Co.), Shiraz Fars, Islamic Republic of Iran e-mail: ehsan.ghanaatpisheh@gmail.com Abbreviations a, b Constants for EOS AAD Average absolute deviation = ∑ (abs |( P dc - P d )/ P d |)/ N ARD Average relative deviation = ∑ (( P dc - P d )/ P d )/ N ¯ B Molal average boiling point COC Coefficient of correlation =  1 - ∑ ( P dc - P d ) 2 / ∑( P dc - P d ) 2 EOS Equation of state f Fugacity k Equilibrium ratio for the component MW C7+ Molecular weight of C 7+ P d Experimental dew point pressure (psia) P dc Calculated dew point pressure (psia) 123