This can be a long story. ...
Published by Jack Zhao, Process Engineer - Produced water and Facilities
This can be a long story. Think that largest user would be Canadian oil sites using warm lime softening to remove hardness and silica from produced water. Other example not directly water but related is water treatment sludge drying/neutralization using lime.
Yes, some issues from unloading to dosing ,sludge recycle and process control and operation,you can get some more ideas via google above topics.