Please, follow these following steps if no saves are stored.
1. Launch the game
2. Start the tutorial
3. Exit the game
Continue from here once a save game has been added. (Named or Autosave)

4. Open your folder C:\Users\[username]\AppData\LocalLow\Live Motion Games\TrainStationRenovation\Save
5. Edit the file that correspond to the name of your save. (With notepad for ease)
6. In the file, hit Ctrl + F search for amountOfSegregableTrash
7. Put 399 to it's value
8. Save and close.
9. Launch the game again.
10. Reload the savegame.
11. Start the tutorial.
12. Follow the guide on the usage of the Segregated Container
13. The achievement should unlock

(Note if this trick won't work, try to add 199 in the value, repeat the steps, if this unlocks the "Segregation Expert" achievement, redo the steps from 7.)