Is it possible to add multiple CalendarInfo to a Gantt Chart.
For example I have many tasks that can run on different time span.
No, that is not possible. I'm afraid I don't understand your requirement, but if you can clarify exactly what you mean by "run on different time span", we can try to help you.
Task one can be done anytime, anyday (like a piece drying..)
Task two can be done only between 8am and 5pm
I guess I could just use a generic calendar, but our object model has a calendar for every resource