【Daily Question No. 278】10.11.2018
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【Daily Question No. 278】October 11, 2018: Briefly explain the reasons for fluctuations in the pressure at the top of a distillation tower (1) Changes in the feed rate of raw materials, especially an increase in light components, will cause the tower pressure to rise; conversely, it will fall. (2) Changes in tower top temperature and reflux. (3) Pressure buildup in the downstream path after fuel gas is discharged from the reflux tank. (4) Changes in feed temperature and bottom temperature of the tower. (5) The instruments are not properly calibrated, or the control valve is malfunctioning. (Unless otherwise specified, all questions and answers are based on hydrogenation units.) ) Correct: 3 wealth, Incorrect: 1 wealth ； Mass posting of posts – rated based on the lowest score ； Replies that are unrelated to the answer are considered spam and will be deleted immediately. For management purposes, if you need to view content from a few days ago, please go to https://bbs.hcbbs.com/home.php?mod=space&uid=3862647&do=thread&view=me&from=space through the summary post below
①If the feed rate of raw materials changes, or if the load on the tower increases, especially due to an increase in the light components, the tower pressure will rise; otherwise, it will fall. ②Changes in tower top temperature and reflux. ③Pressure builds up in the backstream after the fuel gas is discharged from the reflux tank. ④Changes in feed temperature and bottom temperature of the tower. ④The instrument is not properly calibrated, or the control valve is malfunctioning.
①If the feed rate of raw materials changes, or if the load on the tower increases, especially due to an increase in the light components, the tower pressure will rise; otherwise, it will fall. ②Changes in tower top temperature and reflux. ③Pressure builds up in the backstream after the fuel gas is discharged from the reflux tank. ④Changes in feed temperature and bottom temperature of the tower. ④The instrument is not properly calibrated, or the control valve is malfunctioning.
1. Maintain a stable feed rate; or, in response to changes in the feed rate, adjust the heat load distribution at the top of the tower and increase or decrease the amount of exhaust gas emitted. If necessary, control valves or bypass valves can be used for this purpose. 2. Check whether the exhaust gas pipelines are blocked or whether the nozzles are clogged. If the blockages in the pipelines cannot be resolved, divert the exhaust gas to the flare line. 3. Keep the pressure in the gas liquid separation tank stable
(1) Changes in the feed rate of raw materials, especially an increase in light components, will cause the tower pressure to rise; conversely, it will fall. (2) Changes in tower top temperature and reflux. (3) Pressure buildup in the downstream path after fuel gas is discharged from the reflux tank. (4) Changes in feed temperature and bottom temperature of the tower. (5) The instruments are not properly calibrated, or the control valve is malfunctioning.
1. Changes in the feed rate of raw materials, especially an increase in light components, will cause the tower pressure to rise; conversely, it will fall. 2 Changes in tower top temperature and reflux. 3 Pressure buildup in the downstream circuit after fuel gas is discharged from the reflux tank. 4 Changes in feed temperature and bottom temperature of the tower. 5 The instruments are not properly calibrated, or the control valves are malfunctioning
①If the feed rate of raw materials changes, or if the load on the tower increases, especially due to an increase in the light components, the tower pressure will rise; otherwise, it will fall. ②Changes in tower top temperature and reflux. ③Pressure builds up in the backstream after the fuel gas is discharged from the reflux tank. ④Changes in feed temperature and bottom temperature of the tower. ④The instrument is not properly calibrated, or the control valve is malfunctioning.
1 Properties of the feed material and temperature fluctuations 2 Abnormal fluctuations in the liquid level at the bottom of the tower 3 Fluctuations in the exit temperature of the reboiler, leading to temperature fluctuations at the bottom of the tower 4 Abnormalities in the pressure control valve at the top of the tower or abnormal fluctuations in the downstream system 5 Water carried over in the reflux stream from the top of the tower 6 Abnormalities in the reflux stream at the top of the tower, resulting in temperature fluctuations
(1) Changes in the feed rate of raw materials, especially an increase in light components, will cause the tower pressure to rise; conversely, it will fall. (2) Changes in tower top temperature and reflux. (3) Pressure buildup in the downstream path after fuel gas is discharged from the reflux tank. (4) Changes in feed temperature and bottom temperature of the tower. (5) The instrument is not properly calibrated, or the control valve is malfunctioning
①If the feed rate of raw materials changes, or if the load on the tower increases, especially due to an increase in the light components, the tower pressure will rise; otherwise, it will fall. ②Changes in tower top temperature and reflux. ③Pressure builds up in the backstream after the fuel gas is discharged from the reflux tank. ④Changes in feed temperature and bottom temperature of the tower. ④The instrument is not properly calibrated, or the control valve is malfunctioning.
1. Changes in reflux temperature and reflux flow rate 2. Changes in feed flow rate 3. Changes in bottom temperature of the tower 4. Changes in reaction accuracy