Condensate water issues after steam temperature reduction
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To reduce steam consumption, our factory has installed temperature reduction devices. After their installation, there have been no negative effects on the manufacturing process; however, the workers in the workshop reported an increase in the amount of condensate water What’s going on here? Is it normal? Is an increase in condensate water a good thing or a bad thing? Thank you!
So, it seems that fewer steam traps are needed for pipes designed for superheated steam compared to those required for saturated steam
I’m sorry, I didn’t understand； Could you explain it in more detail?
It turns out that the pipes were insulated and equipped with steam traps in order to handle superheated steam. Now that the operating conditions have changed and the temperature has dropped, the insulation remains unchanged; as a result, heat loss may increase. There are also no additional steam traps, so the condensate may not be able to be discharged in time. Pay attention to whether there is an increase in the frequency of \"water hammer\" phenomena in the pipes
In which area is there more condensation water?
Previously, superheated steam was used, and the steam trap would remove a portion of the saturated steam; now, saturated steam is used after passing through a temperature reduction device. This improves the efficiency of steam utilization and ensures thorough vapor liquefaction, which results in more condensate water.
Your answer should be correct; could you explain it in more detail?； Make workers believe that saturated steam is better than the original superheated steam? It’s normal to have an excess of condensate water ； Thank you!
It is well known in the industry that the heat transfer efficiency of superheated steam is lower than that of saturated steam, and this is why you need to carry out technical upgrades. Although superheated steam has high pressure and temperature, it is not possible to liquefy it entirely and release its thermal energy during the heat exchange process. The condensate discharged through the steam trap will contain steam, and due to the high pressure of the steam, the back pressure of the steam trap is also high, resulting in a high discharge pressure. This is what is known as flashing, which leads to the waste of some of the thermal energy. By using saturated steam, it is possible to liquefy almost all of it, releasing thermal energy for use in heat exchange; as a result, more condensate water is produced, which helps save thermal energy.
This post was last edited by ylb913 on 2015-12-11 at 19:29. There is something strange about this issue: steam is superheated in order to prevent condensation during transportation. Reducing pressure followed by reducing temperature is likely due to the requirements of the heated medium regarding the maximum steam temperature (out of concern for local overheating); that’s why cooling water is added, and as a result, the amount of condensate produced after heat exchange increases naturally. But it ultimately comes down to a difference in enthalpy. Assuming that the temperature of the condensate remains constant (which is normal as long as there is sufficient heat exchange area), the enthalpy of superheated steam is higher than that of saturated steam; therefore, more saturated steam is required. As a result, the amount of condensate produced increases. However, this is mainly because the use of superheated steam is not permitted under these conditions – there’s no alternative.
The temperature reduction devices sometimes come with inadequate supporting facilities, and the design institutes may not consider everything thoroughly. This requires enhanced inspections during operation; if there is too much condensate, a manual drainage valve can be considered.