Put on a pair of protective glasses and a mask. This will prevent the wood dust from sanding from getting into your eyes or being inhaled into your lungs.
Begin by sanding the damaged and swollen area with 220-grit sandpaper. Sand the area until the damaged part looks smooth and even.
Sand the entire table until the whole table is even. Several sanding disks will be needed to completely sand down the table
If the table is not perfectly even, mix bleach with water into a bucket. Scrub the entire table with the bleach and water, focusing on the damaged area.
Let the table dry. Sand the surface once more to get a smooth, even finish.
Apply furniture oil to the coffee table. Rub the oil into the table with a rag, adding coats of oil until the desired depth of color has been reached.
Allow the oil to dry.
Apply furniture polish to a clean cloth and buff the table. Do this the following day.