This is a simple guide as to where you can find the various Drone Modules in the game.
Industrial Electromagnet (Biolabs)
It is on a platform, near the first T section, right outside of the OPS of the Biolabs.
However to get to it, you need to take the shortcut near the Tram upwards and go right and drop down into the hole near the wall(either kill the worker and robot or run past them).
Proceed until you come to a platform where one of the rails has been partially dislodged. You can jump onto the right most steel girder in the wall and drop down onto the Platform to get the drone.
Emergency Coolant Vent (Chemical Refinery/Communications Tower)
Emergency Coolant Vent
To get the Emergency Coolant Vent in the Chemical facility you go away from the Tram that lead to the Biolabs and head over the bridge to the right, to enter the Communications Tower.
You then walk up the stairs until you get to the floor where there are two pathways down. Go down and keep going down, you will eventually come to a door that is guarded by an enemy (I also think you may need to have the security rig to access the door but I am not sure), but opening the door is fortunately not mandatory.
Near him there are two crates you can smash. Inside of them you will find the Module.
Flamethrower Tank Module (Research and Development)
Flamethrower Tank Module:
You can find it inside of the Research and Development place. Head out of the OPS and head to the place where you can find Dr. Gene Barret.
Head into the room opposite of his and you will face 3 enemies, one of which will be on top of a platform and shoot gasgrenades at you.
Climb onto the platform, jump on the table, and if you face the wall you can see a shutter through which you can jump.
Inside of that you will find the Flamethrower Module. It will also unlock a shortcut.
Anti-Kinetic Shield (Executive Forum)
When you exit OPS go to your right, enter the room with 3 security guards, there will be stairs leading up on the left, stairs leading down on the right, it’s under the stairs on the right.