Answer: scrape off the traces of glue, soften the glue of each tomette with a steam engine and then sand if necessary.
The solution depends mainly on the surface to be stripped and the amount of glue. If the surface covered with glue is rather large, here is the procedure to follow: to start, you must scrape off the biggest traces of glue with a tile scraper. Then get a steam engine, which will soften the glue on each tile. It will then be much easier to remove. If this is not enough, you will need to use a large belt sander (only if the surface to be sanded is flat! Otherwise, you risk damaging the tiles). If the surface to be sanded is not sufficiently flat, use a small belt sander, and sand the tiles tile by tile. If by chance, the surface to be stripped is smaller, you can use acetone or white spirit. These solvents are effective if you only have a few tiles to clean (and even more effective if you can dismantle them and bathe them in the product). They are however useless on a large surface, because the solvents will evaporate even before you have attacked the glue.