What is a reasonable range for maintaining the liquid level in the steam generator?
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This post was last edited by gwd1988 on 2023-9-15 at 14:04. We are currently designing a batch steam generator, with the normal liquid level being 100 mm above the tube bundle. Taking into account fluctuations in the liquid level, it is necessary to determine an appropriate range for this level. What is a reasonable range for the normal liquid level in such a steam generator? Also, when should high and low liquid level alarms be activated, and when should interlocks for high and low liquid levels be engaged?
The level control of the steam generator generally follows these principles: 1. Normal level: Approximately 100 mm above the tube bundle. This level is necessary not only to ensure thermal efficiency but also to prevent the tube bundle from coming above the water surface when the level is too low, which could lead to overheating. 2. Liquid level control range: Under normal circumstances, the set control range is ±200mm of the normal liquid level. Therefore, if the normal liquid level is 100 mm above the tube bundle, then the reasonable liquid level range should be between -100 mm above the tube bundle (i.e., 100 mm below the tube bundle) and 300 mm. 3. Low liquid level alarm: An alarm should be triggered when the liquid level drops to about 150 mm below the tube bundle, as an excessively low level can cause the tube bundle to overheat and get damaged. 4. High liquid level alarm: An alarm should be triggered when the liquid level rises to about 350 mm above the tube bundle, as too high a liquid level can lead to excessive water cooling, affecting the quality and output of steam. 5. Low liquid level interlock: In addition to triggering a low liquid level alarm, if the liquid level continues to drop to about 200 mm below the tube bundle, the system must be shut down via interlock to prevent the tube bundle from overheating and being damaged. 6. High liquid level interlock: In addition to triggering a high liquid level alarm, if the liquid level rises further by about 400 mm above the tube bundle, it is necessary to shut down the system via an interlock mechanism, as an excessively high liquid level can lead to too rapid cooling, thereby affecting the quality and output of steam. These are some basic settings; the specific liquid level control ranges and alarm thresholds need to be determined based on the actual usage of the equipment and the user’s requirements. .
The level control accuracy can reach ±50 mm; an alarm value of ±100 mm can be set, while an interlock value can also be set at that level. The fluctuation range specified above is 600 mm, which is too large