Water vapor ratio algorithm

Let me give you an example: Given； With a pressure of 4.0 MPa and a temperature of 222 degrees, which is equivalent to 240 °C, and a pressure of 5.97 MPa (the parameters of the process gas at the outlet of the carbon black washing tower), the water-to-gas ratio under these operating conditions can be calculated. By referring to tables of thermodynamic properties, it can be determined that the equilibrium pressure of water vapor at 240 °C is Pe = 3.4138 MPa. Then the comparative pressure is: Pr = Pe/Pc = 3.4138/21.76 = 0.157. In the equation, Pe represents the equilibrium pressure of H2O, in MPa; Pc represents the critical pressure of H2O, also in MPa. Comparison temperature: Tr = T / Tc = (240 + 273) / 647.3 = 0.793. Where: Tc is the critical temperature of H2O, in K. According to Hougen and Watson’s generalized compressibility factor chart, the compressibility factor of water vapor under the operating conditions can be obtained from Pr and Tr tables: Z = 0.89. The water-to-vapor ratio at the outlet of the carbon black washing tower is: Pe/ Z/ ( P - Pe) = 1.50. Where: P is the operating pressure for carbon black washing, in MPa.