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From: Laila Bahgat
This question is not specifically related to WinAsim however I'll very much appreciate any clarification regarding it: Within my MATLAB ASM2d simulations I need to activate the 2 last equations of the model related to the chemical precipitation of P through adding a constant rate of Xmeoh. In a paper I reviewed lately it was written that a dosage rate of 0.6 cubic meters/d equals 600 Kg Xmeoh/ d (although I can't figure out how this comes) so here is what I did: I took this weight equivalent or: 600 Kg Xmeoh/d = 600 * 1000 g Xmeoh/ d ÷ tank volume (say 1000 cubic meters) leading to 600 gm Xmeoh/ cubic meters* day so I added 600 to the derivative equation of Xmeoh of the model and simulated the system. Can someone please tell me if what I did was right or not and how should this constant rate be represented? By the way I have been told that it is erroneous to represent the dosage rate using volume units i.e. 0.6 cubic meters/ day since it should change as its chemical form changes, so how come the paper refers to the dosage rate as a volume and how did they relate this volume unit as equal to the weight unit they mentioned? Thank you very much.
In my opinion, the calculation of a precipitation rate from a dosage rate is rather adventurous. The amount of Phosphate precipitated depends on the amount of Metal added in mol or grams. You can calculate that from the volume added, if you know the metal concentration. If you want to add a constant rate of MeOH, just add a second influent with a constant flow rate and the required Me-concentration. Best regards Christian Abegglen
Thank you for the clarification