How to calculate the evaporation rate of liquid ammonia when the temperature of the liquid ammonia sphere tank increases
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There are two liquid ammonia storage tanks (2,000 cubic meters each), one in use and one as a backup; the backup tank is connected to the main tank at the gas phase. The temperature of the liquid ammonia increases from 16°C to 19°C. What is the evaporation rate of the liquid ammonia? Please specify the calculation formula, thank you. If the pressure increases from 1.5 MPa (gauge pressure) at a temperature of 16°C to 1.6 MPa at a temperature of 19°C, how much liquid ammonia will evaporate? Or, what is the evaporation rate of liquid ammonia for every 0.1 MPa increase in pressure? Thank you.
The evaporation rate of liquid ammonia can be calculated using the difference in saturated vapor pressures. First, it is necessary to determine the saturated vapor pressure of liquid ammonia. Based on the relationship between temperature and pressure, the saturated vapor pressure of liquid ammonia can be calculated using the Van der Waals equation: P = nRT / (V-nb) – an^2 / (V^2). Here, P represents pressure, n is the number of moles (the number of moles of liquid ammonia is proportional to its mass), R is the gas constant, T is the temperature, V is the volume, and a and b are the parameters of the Van der Waals equation. Then, the difference in the saturated vapor pressures of liquid ammonia at different temperatures is calculated, which represents the amount of evaporation: Amount of evaporation = n1 * (P2 - P1) / P1, where n1 is the number of moles of liquid ammonia, P1 is the saturated vapor pressure at the initial temperature, and P2 is the saturated vapor pressure at the final temperature. If the pressure increases from 1.5 MPa (gauge pressure) at a temperature of 16°C to 1.6 MPa at a temperature of 19°C, the amount of liquid ammonia that evaporates can be calculated using the formula mentioned above: First, determine the saturated vapor pressure of liquid ammonia at the initial temperature, P1; then determine its saturated vapor pressure at the final temperature, P2. By plugging these values into the formula, the amount of liquid ammonia that evaporates can be calculated. If the pressure increases by 0.1 MPa, the amount of liquid ammonia that evaporates can be calculated using the formula above: First, determine the saturated vapor pressure P1 of liquid ammonia at the initial temperature; then determine the saturated vapor pressure P2 after an increase of 0.1 MPa. By plugging these values into the formula, the amount of liquid ammonia that evaporates can be calculated. .