Davidships....unfortunately Capt. Carlos isn't more here. But the port is certainly at south of Brazil, at Rio Grande state.

This one is elusive, Edson, but I suspect that it was a cargo barge on the Lagoa dos Patos and owned by Navely Navegação Elichirigoity Ltda, Porto Alegre which seems to have gone out of business some time ago, perhaps in the late 1980s. It would be helpful to know from Capt Carlos where and when the photo was taken, and whether he knows anything further about the vessel.