Questions about principles of chemical engineering
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Two questions. 1. Why does the heating efficiency deteriorate when the tower liquid level is higher than the return port of the vapor phase in the reboiler? 2. How do flow rate, velocity, and pressure change when the valve is closed?
Isn’t that just direct flooding? ； When the valve is closed, the pressure drop increases, the flow rate decreases, and the flow velocity increases
Generally, reboilers operate on the principle of thermosiphon effect to achieve circulation. When the outlet of your reboiler is below the liquid level in the tower, there is insufficient driving force for circulation to take place; in other words, the siphon effect cannot function. As a result, the heat exchange efficiency in your tower is poor, and this condition is known as a flooded tower!
1. If the liquid level is too high, it exceeds the gas outlet, which blocks the gas flow and results in poor heating performance of the heat exchanger. 2 When the valve is closed partially, the flow rate decreases, the velocity of the flow reduces, the pressure before the valve increases, and the pressure behind the valve decreases. --Haomai Chemicals
Hello, could you explain how the pressure control valve of type PICA regulates pressure by adjusting the valve opening?