EQ-COMP is a chemical process simulation software for calculation of bubble point, hydrocarbon dew point, water dew point, phase envelope, compressibility factor, McCabe Thiele curves, gas hydrate equilibrium curve, CO2 freezing and frost curve and other binary / multicomponent vapor liquid equilibrium (VLE) properties for hydrocarbon mixtures / oil and natural gas mixtures. Oil and natural gas samples comprise primarily of non-polar and mildly polar hydrocarbon compounds. EQ-COMP has been developed considering these non-polar and mildly polar hydrocarbons. 

Present day hydrocarbon industry cannot function without accurate knowledge of Vapor-Liquid Equilibrium properties of pure hydrocarbons and hydrocarbon mixtures. Vapor-Liquid Equilibrium properties of hydrocarbons are required in designing and effective operation of each and every equipment involving hydrocarbons ranging from hydrocarbon pumps to pressure vessels and distillation columns. VLE properties are also required in upstream hydrocarbon processes like planning and simulation of oil and gas wells and drilling and production of hydrocarbons. Atmospheres of various heavenly bodies in the universe are composed of hydrocarbons like methane, ethane, propane and heavier hydrocarbons in combination with inorganic gases like Nitrogen, Carbon dioxide and Hydrogen sulfide. Exploration of these heavenly bodies require simulation of their atmospheres which require accurate prediction of VLE properties of the mixture of various hydrocarbons with inorganic gases constituting their atmospheres. Accurate prediction of Vapor-Liquid Equilibrium properties require complex calculations which can only be executed through complex computer programs run on latest computers.

EQ-COMP is a complex chemical engineering process simulation software tool for automatically calculating vapor-liquid equilibrium properties of pure hydrocarbons and binary and multi-component mixtures of hydrocarbons by just clicking a button. EQ-COMP is written using very basic software tools like MS Excel and VBA. EQ-COMP can predict vapor-liquid equilibrium properties for hydrocarbon mixtures for almost any composition with upto a maximum of 112 components using Peng-Robinson cubic equation of state. The possible components can include non-polar hydrocarbons, mildly polar hydrocarbons, non-polar inorganic gases or mildly polar inorganic gases. LIST OF HYDROCARBONS – EQ-COMP.  Various modules of EQ-COMP can be used to find out bubble point temperature, bubble point pressure, hydrocarbon dew point temperature, hydrocarbon dew point pressure, phase envelope, two phase composition and compressibility factor. EQ-COMP can accurately predict VLE properties in retrograde region and for compositions involving high proportions of non-condensates where other similar softwares falter. The phase envelope generated using EQ-COMP consists of equilibrium temperature values at a specified interval of 0.4 bars. This phase envelope clearly marks the critical point of mixture and cricondenbar and cricondentherm for the mixture can also be located on the phase envelope. Carbon dioxide freezing and frost curve for hydrocarbon mixtures containing CO2 can be calculated using EQ-COMP. Carbon dioxide freezing and frost curve is calculated by using temperature dependent binary interaction parameters (BIPs) in Peng-Robinson cubic equation of state. This curve provides safe operating temperature and pressure conditions for handling hydrocarbon mixtures containing CO2 under cryogenic conditions. Separate modules are designed to find out water dew point curve for mixtures containing water between 1 weight % and 50 weight % and gas hydrate equilibrium curve for hydrocarbon mixtures using temperature dependent binary interaction parameters (BIPs) in Peng Robinson equation. Gas hydrate dissociation curve / gas hydrate equilibrium curve for pure hydrate forming components and hydrocarbon mixtures containing at least one hydrate forming component can be calculated using EQ-COMP. Hydrate forming components included in EQ-COMP are methane, ethane, propane, n-butane, i-butane, ethylene, propylene, acetylene, cyclopropane, nitrogen, hydrogen sulfide, carbon monoxide, carbon dioxide, argon and oxygen. Also hydrate equilibrium curves for pure hydrocarbons and hydrocarbon mixtures in presence of hydrate inhibitors like salts (LiCl, NaCl, KCl, CsCl, CaCl2 and MgCl2), salt mixtures, organic liquids (methanol, ethylene glycol, ethanol, 1-propanol, 2-propanol, t-butyl alcohol and glycerol) , sugars (deoxyribose, ribose, fructose, sucrose, glucose and maltose), urea and formamide can be calculated using EQ-COMP. Concentration diagrams (x-y plot), temperature concentration diagrams (T-x-y plot) and enthalpy concentration diagrams (H-x-y plot) can be generated for binary mixtures using binary VLE calculation module of EQ-COMP.  These diagrams can be used in Mc-Cabe Thiele method and Ponchon Savarit method to design distillation columns for binary hydrocarbon mixtures. More accurate basic stage by stage design calculations for binary distillation columns and multi-component distillation columns to find out minimum reflux ratio, number of equilibrium stages in rectification section and stripping section, equilibrium temperature of various stages and liquid and vapor compositions at various stages can be performed using multicomponent distillation calculation module of EQ-COMP. Also various thermodynamic properties for hydrocarbon mixtures like enthalpy, entropy, gibbs free energy, specific heats, sonic speed, isobaric thermal expansivity and joule thomson coefficient can be calculated using thermodynamic properties calculation module of EQ-COMP. Upto a maximum of 40 Pseudo components can be included in various VLE calculations using EQ-COMP.  EQ-COMP can also be used to find VLE properties of mixtures containing few highly polar compounds like carbon monoxide (CO) and ammonia (NH3). 

Bubble point software / calculator, hydrocarbon dew point software / calculator, water dew point software / calculator and other calculation modules of EQ-COMP are available for use through VLE CALCULATOR page.

Vapor liquid equilibrium software

Phase Envelope for a typical natural gas composition