kthaxton
TDR MEMBER
I am responsible for large deionization systems at my work. DI water has quite a range of purity level and can still be considered Deionized. Further, bacteria can exist in it and be undetectable by traditional means of measurement (resistivity).
Any evaporation process using distilled water (like a humidifier) that leaves traces of mineral, is likely from what the water mist absorbed from the air.
For all intents and purposes however, higher purity DI water is as good as distilled and can usually be used interchangeably, but as mentioned above, not a good idea to drink because bacteria can exist in it.
Economics is likely the only reason to use DI water in a manufacturing process (i.e. DEF) vs. distilled.
In the end, they are merely two different methods to achieve a similar level of purity, distilled is just more reliable in its purity.
Any evaporation process using distilled water (like a humidifier) that leaves traces of mineral, is likely from what the water mist absorbed from the air.
For all intents and purposes however, higher purity DI water is as good as distilled and can usually be used interchangeably, but as mentioned above, not a good idea to drink because bacteria can exist in it.
Economics is likely the only reason to use DI water in a manufacturing process (i.e. DEF) vs. distilled.
In the end, they are merely two different methods to achieve a similar level of purity, distilled is just more reliable in its purity.