Seeking everyone's advice on steam electric heating
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The original distillation system had a long reaction time, with low steam pressure and temperature – around 0.5 Mpa and 165°C. Therefore, a 35 kW electric heater was added to the main distillation steam pipeline in order to raise the steam temperature; the target heating temperature was set at 200°C. However, tests conducted during recent production have shown that the temperature at the outlet of the electric heater can indeed reach 200°C, but this does not have a significant impact on the distillation process, and the reaction time remains long. Could anyone tell me what the reason for this is? After exiting the steam drum, the distillation steam passes through an electric heater and then is divided into three streams, which go respectively to the distillation columns A/B/C. See the figure below for details
What is the material? Has the reflux ratio been increased? What are your expected outcomes? Raising the steam temperature can only increase the extraction rate; it doesn’t help with anything else
You heated the saturated steam, which served as the heat source, using the pipes, turning it into superheated steam; fortunately, the degree of superheating was not high, otherwise the heating effect would have been even worse. The heat used for this process came from the latent heat, which is the energy released when steam turns into water. When the temperature is increased while the steam pressure remains constant, the steam becomes superheated, and its sensible heat increases; this sensible heat cannot be released unless the latent heat is also released
A higher temperature only increases the sensible heat slightly, which is negligible when it comes to the heat transfer amount
If you find a process technician with a few years of experience in the chemical industry to help, they won’t use such a heating method.
If the problem cannot be resolved with steam, the heating method will have to be modified.
Using superheated steam results in a lower heat transfer coefficient compared to saturated steam, so the effect is not significant. To solve the problem, it is necessary to increase both the steam temperature and the steam pressure.
You can increase the distillation speed by raising the steam flow rate or expanding the heating area
Is the distillation effect not significant? If it refers to substandard products, that would be another topic for discussion. If it’s a lack of heat, it fits the description; adding an electric heater for overheating and increasing the amount of sensible heat should yield only mediocre results. If possible, consider operating under negative pressure to lower the boiling point