The process of water evaporation from flue gas
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I would like to ask: When water at 20 degrees Celsius is sprayed into a large amount of unsaturated flue gas at 180 degrees Celsius, the temperature of the flue gas drops from 150 to 80 degrees Celsius, and the flue gas remains unsaturated at the end. In this process, does the water first heat up before vaporizing, or does it vaporize first before heating up?
The vaporization of water is relative to the influence of the surrounding environment on it. In nature, water is constantly vaporizing and condensing to reach a certain balance. When the environment of water changes, it turns into water vapor by absorbing heat; conversely, water vapor turns back into water. (After accounting for humidity factors). As for whether smoke can turn water into steam, that is inevitable; as the smoke passes through the water, its moisture content reaches saturation. As water evaporates, its temperature rises. If the water temperature is to remain constant, evaporation is necessary; it allows a large number of water molecules to evaporate, thereby carrying away heat and keeping the water temperature stable. (This might be a provocative question.) It’s an insight I gained from the cooling principle of the venturi in converter flues.
The process isn’t important; what matters is the result. The initial and final states already reflect the energy transformation process
How do you say synchronization? Shouldn’t it require external energy to vaporize? Even for just a moment, it’s the temperature that rises first, right?
Engineering technology is of an applied nature; there is no need to understand the intermediate states, as those processes are very complex. We can simply simplify things: in the transition from one state to another, regardless of how the process takes place, the end result is that we are in another state. All we need to know are the initial and final states in order to calculate the amount of energy change that has occurred in between
You can take a look at the explanation of Bernoulli’s equation: it concerns the states of two points, and regardless of the path taken in between, the change in energy between those two points remains constant
This is incorrect. It’s fine for water to boil and vaporize when it reaches its boiling point, but it can also vaporize below that temperature; it just can’t be called boiling. Evaporation is also a process that can achieve gasification. I think spray cooling is more like an evaporation process, utilizing the heat absorption that occurs during evaporation.