Simulation related to three-effect downstream evaporation of electrolytic alkali solution
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Hi friends, does anyone have any experience in simulating the evaporation and crystallization of electrolytic alkali solution? I recently want to learn how to crystallize an electrolytic alkali solution containing 10% NaOH and 18% NaCl through three-effect co-current evaporation to NaOH 30%. , NaCl5.8% electrolytic alkali solution flow rate is 40000kg/h, system washing water volume is 500kg/h, first-effect heating steam pressure is 6kg/cm2 (gauge pressure), third-effect vacuum degree is 650mmHg, and the third-effect heat transfer coefficient is respectively: 1500.1000.800 kcal/m2·h·℃, the average specific heat of the material liquid is 0.9 kcal·kg·℃. Calculate the heat transfer area of each effect evaporator. (The attached picture is an example question. I am a beginner and want to simulate learning by following the example question. * study * , if you have done similar simulations, I hope you can give me some advice. If you have similar simulation files, I hope you can share them so that I can learn from them. * Thank you! ! ! ! )
I still haven't figured out the material balance thoroughly, I want to understand it through simulation.
I know how to do calculations by hand, so what’s so difficult about computer calculations?
If you can do calculations by hand, what's so difficult about computer calculations?
Some of the calculations in the example questions didn’t work out, so I thought of using the conditions of the example question and ASPEN to simulate it. If you know how, teach me: lol
Some of the calculations in the example questions didn’t work out, so I thought of using the conditions of the example question and ASPEN to simulate it. If you know how, teach me: lol
Some of the calculations in the example questions didn’t work out, so I thought of using the conditions of the example question and ASPEN to simulate it. If you know how, teach me: lol
I feel like there is something wrong with the material balance calculation.: From 10% to 12.3% The amount of evaporated water and crystallized salt is a certain amount, as shown in the calculation, but adding wash water is different. After the cleaning water is added, the evaporated water will increase from 10% to 12.3%, and then the crystallized salt will remain unchanged.
Another problem is the increase in boiling point caused by static pressure: Generally, the material enters the evaporation chamber directly from the upper part after being heated up by the heat exchanger to evaporate. Therefore, it evaporates directly after entering the evaporation chamber. The static pressure is not considered, because the material below the liquid level needs to be cyclically heated and then evaporated. It is not the kind of interstitial evaporation. Therefore, I personally think that the increase in boiling point caused by static pressure can be ignored.
The change in boiling point caused by static pressure is relatively small, but it should still be considered in theoretical calculations to provide better guidance in engineering practice.