Seek advice on determining the recovery temperature for light hydrocarbons in natural gas
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The main components recovered are heavier fractions such as ethane. In actual production, the pressure in the demethanization tower is around 1.35 MPa; the ethane content is approximately 3%, resulting in a partial pressure of around 0.04 MPa. The saturated vapor pressure of ethane lies between -110 and -100°C, yet the actual operating temperature is -80°C. Why is that? Can propane still be recovered when the temperature is above the saturated vapor pressure? Where did I go wrong? ? ? ? ?
You see, the proportion of ethane is around 3%; during the low-temperature separation stage, propane and other compounds liquefy first, so the proportion of ethane can increase to around 5%. Using the actual pressure of 1.35 multiplied by 5% of the volume, the partial pressure comes out to 0.0675 MPa. The unit on the saturated vapor pressure table is 0.1 MPa; does 0.675 MPa correspond to a temperature of -95°C?
How is the relationship between saturated vapor pressure and dew point calculated? The ethane recovery rate in the plant is around 50%. What is the relationship between dew point temperature and saturated vapor pressure?