As an important procedure of the manufacturing process in refinery

oil blending could be abstracted as a complex non-linear optimization problem (NLP) with many constraints. It is difficult to obtain satisfying optimum solution by traditional methods. According to the oil blending and scheduling problem

a two particle swarms optimization algorithm with a mutation operator was presented. The proposed algorithm constructed two swarms of particles with different velocity restrictions

introduced a communication mechanism and a special mutation operator

and sequentially elevated the swarms to higher ability and velocity of global convergence. The new method was illustrated with a recipe optimization problem of gasoline blending

and the feasibility and effectiveness of the proposed algorithm was experimentally confirmed by the simulation results.