$17.$ The concepts of degree of separation and degree of difficulty of separation are vital for refining operations, as they influence decisions regarding $\_\_\_\_$ configuration, $\_\_\_\_$ management, and $\_\_\_\_$ optimization.

$18.$ Packie charts facilitate the optimization of $\_\_\_\_$ points in distillation columns, enabling refineries to improve $\_\_\_\_$ yield and $\_\_\_\_$ quality.

$19.$ In refining operations, desalting effectively removes contaminants like $\_\_\_\_$ and $\_\_\_\_,$ which, if left untreated, could cause $\_\_\_\_$ and $\_\_\_\_$ in downstream processes.

$20.$ Stabilization of crude oil is essential for safely transporting and storing the oil by removing $\_\_\_\_$ components, thus preventing $\_\_\_\_$ release and maintaining $\_\_\_\_$ quality.