Oddworld: Soulstorm Enhanced Edition

PuckJunkie's guide is helpful and accurate, I unlocked this in a single level using a single recycling machine, but is missing one very important detail. You have to recycle EXACTLY 100 bottles, similar to the issue with the moolah gates. If you turn in 101 or more, the achievement will not unlock. I also did not have to start a fresh save so I don't think that step is necessary.

Use the level Feeco Depot, there are more than enough bottles in this level if you hit the secret areas early on and search all lockers/trashcans/dumpsters/boxes. Once you have 99 bottles in your inventory, find a recycling machine that has some bottles on the ground somewhere nearby. Turn in your 99 bottles and then carefully pick up ONE more from the ground. You can crouch and use sneak to creep forward in small increments to make sure you only grab one. Now go turn in that last one, making 100, to the same machine you already gave your first 99. Achievement should unlock.

First, note that even though the text doesn't mention it, you'll need to do this within a single level. That was the case in the PS version, reportedly, and it appears to still be the case.

In fact, I was only able to get it on a fresh run, turning in all the bottles in at a single recycling vending machine, without leaving the area.. Playing in level select did not move the tracker. Turning in over 100 bottles in a single level on a fresh run, but across multiple vending machines, did not help - although it did increase the tracker counter to 95 when I actually turned in that many at one of the machines. It increased to 99 when, on a fresh run, I turned in 99 at once; but when I backtracked to the machine after getting another bottle, it did not unlock.

I got this achievement on level 6, "Phat Station," which I believe is your earliest opportunity. On a new run, save up all your bottles until you have 99 and there are unsearched bins/trashcans near a recycling machine. I turned in 99, then climbed up a ledge directly above me to grab one more from a bin. When I dropped back down and turned it in, it unlocked the achievement.

Good luck.