If anyone know the definition about process and non-process.
Electricity will fall under process or non-process.
As air, water, steam and nitrogen falls under nitrogen so same as electricity also falls under utility ?
Really vaguely worded question but in my mind, process is all the piping directly associated with chemical feeds, process side of heat exchangers, etc. Whatever your "process" is - stuff handling the raw materials, intermediate components/materials, and final components are "process".
"Utility" is everything else that supports the process work. Chilled water, river water, steam, nitrogen, air, etc...You need these for the process/equipment to work but they aren't process lines.
Strictly, process means "a series of steps or actions taken to achieve a particular end".
In real life process industries, the "process" side of piping and/or cabling refers to stuff actively involved in the process either through control, material handling, or movement. "Non-process" would be everything else - up to and including the utility connection on the electrical side or the water/gas equivalent on the mechanical side.
Converting energy to motion for more than half a century
As far as I know, there's not a code or standard that explicitly defines process vs non-process or utility. Since different requirements may apply to systems that are considered part of the process vs not, it's always best to confirm the definition with whomever is responsible. I've had customers with more or less generous definitions of what is considered process vs utility piping, which drove different requirements for things like NDE, for example.