【Daily Question】1.15 Short-answer question: Causes of changes in the low liquid level in the initial distillation tower
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This post was last edited by Catalyzing a Grain on 2016-1-22 at 10:22. Brief question: What are the reasons for changes in the low liquid level in the initial distillation tower? Changes in feed rate, changes in crude oil properties, changes in feed temperature, changes in tower top pressure – Correct: +2; In-depth discussion: +5 @Guan Gongyu
1. Changes in the feed rate to the fractionating tower and the amount pumped out by the pump at the bottom of the fractionating tower. 2. Fluctuations in the liquid level at the bottom of the tower due to changes in the properties of the crude oil. 3. Changes in the feed temperature to the fractionating tower. 4. Variations in the top pressure and temperature, which affect the liquid level at the bottom of the tower. 5. The vaporization rate.
What are the causes of changes in the low liquid level in the initial distillation tower? Answer: Changes in the properties of crude oil, changes in the feed volume, changes in the feed temperature, and changes in the top pressure of the tower.
Answer: The small diameter of the initial distillation tower results in a high flow rate per unit volume, and minor fluctuations in the crude oil flow can cause changes in the liquid level at the bottom of the initial distillation tower. The main reasons for changes in the bottom liquid level of the primary distillation tower include: (1) changes in the feed flow rate to the primary distillation tower and the discharge flow rate from the pump at the bottom of the tower. When adjusting the processing capacity or the liquid level at the bottom of the initial distillation tower, the flow rates in and out of the tower are not properly balanced. For example, if the flow rate into the tower is high and the flow rate out of the tower is low, the liquid level will rise. (2) Changes in the properties of crude oil will cause fluctuations in the bottom liquid level. For example, the crude oil becomes heavier, and the liquid level at the bottom of the tower rises ； The crude oil becomes lighter, and the liquid level at the bottom of the tower drops. (3) Changes in the feed temperature of the initial distillation tower. When the top temperature is not adjusted in a timely manner, the feed temperature is high and the liquid level drops ； A low feed temperature causes the liquid level to rise. (4) The levels of pressure and temperature at the top of the tower affect changes in the liquid level at the bottom of the tower. The high temperature at the top of the tower and low pressure reduce the vaporization rate of oil within the tower; the unvaporized oil moves to the bottom of the tower, causing the liquid level there to rise ； The temperature at the top of the tower is high and the pressure is low, while the liquid level at the bottom of the tower decreases.
1. Changes in the feed rate to the initial distillation tower and the amount pumped out by the pump at the bottom of the tower. 2. Fluctuations in the liquid level at the bottom of the tower due to changes in the properties of the materials. 3. Changes in the feed temperature of the initial distillation tower. 4. Variations in the top pressure and temperature of the tower, which affect the liquid level at the bottom of the tower
1. Changes in the feed rate to the initial distillation tower and the discharge rate from the pump at the bottom of the initial distillation tower； 2. Fluctuations in the bottom liquid level caused by changes in crude oil properties ； 3. Changes in the feed temperature of the initial distillation tower ； 4. The levels of pressure and temperature at the top of the tower affect changes in the liquid level at the bottom of the tower.
What are the causes of changes in the low liquid level in the initial distillation tower? Reasons for changes in the bottom liquid level of the initial distillation tower: High water content in the crude oil ； Low heat exchange temperature ； Changes in crude oil properties ； The material balance wasn’t managed properly ； Changes in tower top pressure ； Changes in tower top temperature.
1. Pressure and temperature at the top of the tower 2. Feed temperature and flow rate of the distillation column 3. Changes in the properties of the crude oil
The pressure at the top of the tower decreases, the crude oil feed becomes lighter, and the feed volume drops.
Generally: feed rate, pump operation status, changes in raw material properties
⑴Changes in the feed flow rate to the primary distillation tower and the flow rate pumped out by the pump at the bottom of the tower; (2) Changes in the properties of the crude oil can cause fluctuations in the liquid level at the bottom of the tower; (3) Changes in the feed temperature of the primary distillation tower; (4) Variations in the pressure and temperature at the top of the tower affect the liquid level at its bottom