Why isn’t normal temperature steam used for heat transfer in industry?

What is the state of water vapor at room temperature? How low must the vapor pressure of water at 50 degrees be, and how much heat can it transfer?

Heat exchange also requires consideration of heat exchange efficiency and the utilization of waste heat. It’s not about mechanically considering only the factor of high latent heat.

This post was last edited by zzjp on 2016-4-25 at 18:11. Higher latent heat means higher heating efficiency; what about the utilization of waste heat? It’s difficult to make use of the condensate water

The owner faces the following disadvantages when using atmospheric pressure steam: 1. The material to be heated cannot be heated if its temperature exceeds that of the steam (as high-pressure steam has a higher temperature). 2. The heat exchange efficiency is low due to a small temperature difference between the steam and the material; for example, to heat water from 100 degrees Celsius to 90 degrees Celsius using steam at 100 degrees Celsius, a large heat exchanger is required, even after taking phase changes into account. However, with high-pressure steam at 200–300 degrees Celsius, a smaller heat exchanger would be much more economical. The original poster should consider both the first law of thermodynamics and the second law of thermodynamics. Second law of thermodynamics: It is impossible to transfer heat from a colder object to a hotter object without causing some other change.

Is the high-pressure steam of over 200 degrees you mentioned saturated steam?