In previous works CO2 emissions in oil refineries have been studied for production unit planning. In this manuscript the associated CO2 mitigation costs are added to the scheduling of crude oil unloading and blending. Numerical simulations executed on literature cases show that the optimal scheduling may be affected, and thus CO2 emissions may be greater than those predicted from production unit planning. Furthermore, the biobjective problem of maximizing profits and minimizing CO2 emissions is studied; pareto-optimal solutions and the lowest carbon pricing that induces the refinery to minimize CO2 emissions are presented for each case.