The image below is a schematic flow diagram of a typical oil refinery that depicts the various unit processes and the flow of intermediate product streams that occurs between the inlet crude oil feedstock and the final end products.
In order to check-in into a hotel, the person must be 21 years old.  If the person is younger than 21, then a parent or guardian can  give permission for them to check-in. 1 person found this useful.
Generally the answer is 18. If you have your parentsâ consent to rent a hotel room, you can rent hotel rooms in Europe at age 16. Since that generally requires you using your parentsâ credit card, this regulation is pretty self-enforcing.hose walking into a hotel with a 21 age limit might test the policy. Hotels might be willing to rent to 19- and 20-year olds if you have the identification and driverâs license. Itâs not illegal to rent to you, so their policy becomes a matter of preference and circumstance.