Thanks for both replies. Flow comes from bottom up through solids and probably is well distributed. Near exit, fluid has to accelerate from 1X to 10X out the outlet pipe. Without CFD to draw pretty arrows, I have to assume the flow nearest to the pipe has the highest vertical velocity and...
A properly designed settler or clarifier has an overflow launder to distribute the upward velocity evenly around the tank. But when a cylindrical tank is installed with a single overflow outlet, say with an outlet velocity 10X the upflow velocity, what is the magnitude of the effect on upflow...
Another significant effect on pH is the temperature. If your temperature control range is wide, especially at the point of pH measurement, you will see a lot of variability in pH in addition to that caused by the caustic variability. Long time ago I ran a stripper with temperature and pH as...
Thanks TBP, I haven't done one in quite a while. For the liquid streams I assumed an outlet temperature for one, then calculated the outlet for other from m*Cp*dT. Also assumed exchanger size and calculated log mean dT and heat transferred, BTU/h. Changed assumed outlet until heat change in...
What is the best way to estimate size of exchanger in a tank recirculation loop to heat a tank of fluid from one temperature to another in a given time using a steady (and limited) flow of heating fluid at constant supply temperature? It is unsteady state in that the process inlet to the...
Thank you for the response. We already have level controls in the receivers that don't work very well and the pumps frequently lose prime. A strictly hydraulic solution would be very attractive. Seems like the balance line would have to be much smaller than the process lines to avoid...
Vacuum filtrate receiver pump occasionally pumps receiver empty and loses its prime when level control fails. Pump is about 10 feet below bottom of receiver. An old filter manual says that receivers can be fitted with an added connection for centrifugal pumps to prevent loss of prime. However...
Are there some rules of thumb for accuracy of estimates at various stages of engineering, like ballpark, back of envelope, preliminary engineering, detailed engineering, etc? Seems like I have seen figures from 250% going down to 10% as engineering effort is expended.
EvW - Presumably you are mixing a tank with the circulating pump. You can get as detailed or as simple as time allows. If your tank mixing seems fairly turbulent, consider it a stirred-tank and the rule-of-thumb is to wait for three turnovers to get 95% of a step change. A 1000 gallon tank...
WMS helped very much! Although my application was a dilute solution of ethanol in water, the Tank 3.1 program allowed me to estimate maximum loss from pure ethanol so that I had a number to show my environmental engineer. Thirty years after my last diffusion calculation, I needed a simple aid...
