Not sure where Vilanova Park is, but there are two Carrefour's: one on the outskirts of Tarragona (Les Gevarres), and one in Reus.The one in Tarragona is probably the better of the two, if you intend to do other shopping whilst there: it is in the main shopping centre, and there are quite a few other large supermarkets, and two Chinese 'supermarkets'(they sell all sorts of things...typical Chinese quality,AND PRICES!!) there too.
Looking on Google, it looks like the Vilanova Park is just south of Sitges?? So probably about 40 miles from Salou. If it is the place just south of Sitges, I think the address for the nearest Carrefour will be:-