I’d like to ask the seniors about the process of the MVR evaporation system.
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The boiling point elevation we designed for was 10°C; now we are continuing to reflux and evaporate the mother liquor (we’re not sure exactly what it is, as its color is much darker than before). Once further evaporation was no longer possible, we measured a boiling point elevation of 12°C. I would like to ask what else can affect the boiling point elevation besides the solution concentration? How do I measure this thing? Can it be proven using conductivity?
It should be the result of it becoming thicker,,,
Could it be a high-boiling-point organic compound that is completely miscible with water? Try extracting it and see
Weren’t we already able to measure it (12 degrees)? Now, it is only possible to discharge the mother liquor in an appropriate amount; by controlling the increase in boiling point, operations can be maintained.
This post was last edited by sifangok on 2017-9-10 at 14:59. When designing an MVR evaporator, the boiling point at the desired concentration ratio is a very important parameter. For strong electrolyte solutions, the design temperature rise can be determined by plotting a concentration-boiling point curve; for solutions containing organic substances, the design temperature rise can be determined by plotting a solution density-boiling point curve (since measuring conductivity in the presence of high levels of organic matter does not yield accurate estimates of the material concentration). To measure the boiling point, the micromethod should be used; otherwise, it may lead to significant errors. To reduce such errors, measure the boiling point of water before using the thermometer. The boiling point is primarily influenced by air pressure and the components of the material along with their concentrations
The increase in boiling point caused by the continuous concentration and accumulation of high-boiling-point organic substances, once it exceeds the temperature rise allowed by the compressor, leads to a sharp decline in the system’s processing capacity and efficiency.
It is related to factors such as pressure, concentration, and the presence of impurities (coking, heavy boiling substances), etc. If the color turns black, it is likely due to the presence of impurities or the accumulation of impurities in the mother liquor after multiple cycles, causing its concentration to exceed the calculated value. Is it possible to take a sample, evaporate it to dryness, and check what the solid content is, so as to compare it with the calculated value?