How is residence time calculated? ?
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Excuse me, how is the duration of stay calculated? For example, a tower has an inlet volume of 20 m3, an outlet volume of 20 m3, and a total volume of 500 m3. There are three circulation pumps in operation, with each pump having a circulation capacity of 3600 m3. How is the liquid residence time calculated?
I think 500÷20 is the residence time. As for the three circulation pumps, they shouldn’t affect the residence time, right?
That’s how I understand it; I’m not sure if it’s correct. Feel free to give your feedback~~ Why is there a loop? Is this an absorption tower? But in any case, the cycle is just an internal cycle; it has nothing to do with the residence time. But the residence time generally referred to is that of the bottom of the tower, and it has no direct relation to the 20 units of material fed in; it should be determined based on the output volume from the bottom of the tower. Moreover, the residence time refers only to the area indicated by the liquid level gauge at the bottom of the tower, not to the total volume of the entire tower. Are you sure that those 500 m3 refer to the bottom of the tower?
There are two types of residence time: cycle residence time = volume of slurry at the bottom of the tower/cycle volume； Material emptying residence time = Volume of slurry at the bottom of the tower / Slurry discharge rate
Use the bottom liquid level height to calculate the volume of that portion, and divide it by the discharge flow rate.
Dwell time: refers to the period during which something remains inside without leaving. Cycles cannot be considered together in this context; if something stays inside without exiting, it cannot be called a cycle.
The discharge flow rate has no circulation volume.
The operating height of the bottom liquid level gauge is the volume between the low-low level of the liquid at the bottom of the tower divided by 20, in cubic meters per hour; it can also be converted to minutes or seconds. If there is no low level, then it is simply the volume below the operating level of the liquid level at the bottom of the tower divided by 20. 500 is an imaginary number; your tower isn’t operating at full liquid level, right?
Residence time = (liquid level volume * liquid level percentage) / 20 m3/h. I believe the author is referring to residence time in this sense; if cycle residence time is taken into account, what is its significance then? As I understand it, \"dwell time\" refers to how long the material stays inside the container before coming out; so perhaps there’s no need to consider circulation