baggage conveyor and baggage carousel are at an airport, that delivers checked luggage to the passengers at the baggage claim area at their final destination and conveyor belt is mostly used to transport materials such as large volumes of resources and agricultural materials, such as grain, salt, coal, ore, sand, overburden and more.

Baggage conveyor and baggage carousel bring almost the same meaning. They are interchangeably used between British and American. I come across carousel in the USA more often there than here in Malaysia as British English is the preferred standard of language. Conveyor belt is just specifically referring to the a specific belt that function to move any thing on it. So, it is not necessary refering to luggage. You could say, ' The luggage is on the conveyor belt.' We would know that the luggage is being moved by belt. ' The luggage is on the belt' would mean that luggage is just static (not moving) on the belt. The carousel ( although also describe the action of moving) denotes that something is being moved but around a centerpiece or counter instead of just moving. So, if the luggage is moved around a centrepiece in the airport, that is why the word 'luggage carousel' is used..just like a merry-go round.