Use of smoke towers for air raid defence

Hi,

I'm looking for information regarding the use of smokescreens on land. We have smoke towers in the Haifa bay area (Palestine/Israel) that were built by the British during WW2. They are part of a bigger system but only 3 are still standing. We believe the smoke towers were used to defend the port/air field/oil refinery against day time air raids, and were part of a big defence system that was deployed in the area. Haifa was air raided during the war but we don't know if the smoke screen was ever used. The towers have a bottom section and top section with chimney bricks and large roof opening.
Hoping to find some information regarding how they worked, when they were built, were smoke towers used in other locations and so on. Any information will be great since we know very little and hope to restore them.


Cheers,
Uri