I have a question regarding the condensation of low-temperature water vapor
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Hello everyone, I’m new to the refrigeration industry and would like to ask for advice on a solution for the condensation of low-temperature water vapor. Under negative pressure (approximately -96 kPa, with the negative pressure being generated by a water pump and a jet injector), the boiling point of water is around 34 degrees. The subsequent condensation stage in the equipment requires the vapor to be condensed back into water before it can be discharged; the conventional approach involves using a coiled tube heat exchanger, with the refrigerant flowing through the tubes while the water vapor flows through the shell. I was wondering if there are any better solutions, as coil-type heat exchangers are too large in size. Is it possible to use plate-type heat exchangers, which could achieve the same purpose while **reducing the size**? If that doesn’t work, could you explain what problems or potential risks might arise from using a plate heat exchanger to cool low-temperature steam? Thank you so much! :handshake
It is entirely feasible to use plate exchangers in the evaporation plant; the system operates under negative pressure as well. The final stage involves plate cooling, which is used to condense any excess steam into water and remove it
Okay, by the way, I would like to ask how to calculate the heat exchange area for a plate exchanger used with condensed steam. Compared to cooling liquids, by how much does the heat exchange area need to be increased?
What about the parameters? Steam volume, temperature, condensate water volume, temperature. I can help you calculate them. As for how to do the calculations, it can’t be explained in just a few words; you’ll need to study on your own
Thank you. For example, if the steam volume is 50 L/h (the amount after all the steam has condensed into water), the temperature is assumed to be 33 degrees by default; only the condensation work is taken into account. The cold side represents the air circuit with a 10P compressor operating at full load. For any parameters that are not specified, please help to define them customarily{:1_90:}
The steam carried away by the water jet pump – once it mixes in, doesn’t it turn into water? ? No special cooling is required; if the back pressure is high and the pressure cannot be withstood, a water ring pump can be connected in series!
There are many types of condensers available, differing only in their structural design. It’s just that without corrosive gases, using a water jet unit is a bit outdated; the vacuum system can be modified.
I don’t think you need a low-temperature condenser at all. You mentioned that negative pressure is achieved by using a water jet pump to draw in low-temperature steam; the outlet of the jet pump is at normal pressure. It’s as if the steam is compressed and then directly condensed into water.