Production Technology [Weekly Topic]: Production Q&A – Operation of Reboilers (2011-01-10~16)
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This post was last edited by shmily327 on 2011-1-21 08:57. Production Q&A: Please briefly describe the operation procedures for putting a reboiler into use. Remarks: 1. Participation is rewarded ； 2. Please hide your replies; for instructions, see: http://bbs.hcbbs.com/thread-492556-1-1.html. 3. Do not edit your replies after posting them. 4. The moderator will announce the answers in a timely manner. 5. Correct answers with thorough and reasonable analysis earn +1 charm. Key points for answering: introduce steam, supply steam, activate the traps, remove non-condensable gases (from high points), and pay attention to the heating rate.
Drain the water from within the tube side or shell side where the heat transfer oil flows. Slowly add the heat transfer oil and then raise its temperature.
This post was last edited by chinazwr on 2011-1-10 07:54. 1. First, drain the condensate water from the reboiler and open the steam trap； 2. Feed material to the reboiler ； 3. Once the liquid level of the material in the mixer is above that in the tube bundle, steam is introduced, with the amount of steam added or the steam pressure being controlled ； 4. Remove non-condensable gases through the non-condensable gas discharge valve ； 5. The temperature of the reboiler is controlled within the specified process parameters.
a) Open the drain before the inlet isolation valve to discharge the water accumulated in the pipe. b) Slightly open the condensate valve and the pre-valve drain to drain the water accumulated before the reboiler. c) Open the valve in front of the trap and the drain weir after the reboiler to drain all the water accumulated inside it. d) Slightly open the inlet and outlet isolation valves; when steam is discharged from each drain but no water flows, close those drains. e) Fully open the inlet and outlet isolation valves as well as the condensate discharge valve (start up the trap). f) If the condensate is not discharged in a timely manner, the bypass valve of the steam trap can be opened appropriately.
1. Open the drain valve to discharge the condensate water from the reboiler. Slightly open the drain valve again. 2. Open the steam trap assembly of the reboiler; when the reboiler is first started, the condensate flows through the bypass line of the steam trap. Prevent impurities from clogging the steam trap. 3. Introduce some steam into the reboiler; close the drain valve once steam starts to emerge from it. 4. Open the vent valve of the reboiler to discharge non-condensable gases, then close it. 5. Open the steam inlet valve to the specified value.
A reboiler is a special type of shell-and-tube heat exchanger that is installed at the bottom of certain towers. It allows the light components in the liquid phase at the tower bottom to be returned into the tower, thereby providing the heat required for separation processes as well as the vapor reflux needed. It is divided into kettle-type reboilers and thermosyphon reboilers. (1) Inspection and verification: Ensure airtightness is satisfactory, and drain all water from the equipment and pipelines ； Check to confirm that the corresponding heating steam is available ； Improve the single-tower circulation process, put into use the circulating water cooler and chilled water cooler, and start the vacuum pump system to create negative pressure in order to remove non-condensables from the top of the tower. (2) Pipe warming and preheating: Open the exhaust valve on the shell side of the reboiler and the bypass valve on the steam line, then begin to slowly warm and preheat the pipes. (3) Temperature rise and stabilization: Once a liquid level is observed in the bottom of the tower, increase the heating steam flow rate to the reboiler, close the bypass valve and the exhaust valve, and raise the temperature at the bottom of the tower at a rate of 20–30°C per hour; once this temperature reaches the required process value, maintain it at that level ； When the liquid level in the reboiler tank reaches 60%, the controller is set to automatic mode to maintain the top pressure within the requirements specified by the process
1. Cleaning, purging, and pressure testing. 2. Blow dry the residual liquid inside, then increase the temperature gradually
Operational note: The water inside the tube side or shell side where heat transfer oil flows must be completely drained. Slowly add the heat transfer oil and then raise its temperature.
The water inside the tube side or shell side where heat transfer oil flows must be drained completely. Slowly add the heat transfer oil and then raise its temperature.
This post was last edited by *nyang3390 on 2011-1-16 21:27. I want to learn* it*; could you share some materials with me? chenxuhui251@163.com
Drain the medium from the tube side or shell side before heating up and putting the reboiler into use