Soft Constrained MPC Applied to an Industrial Cement Mill Grinding Circuit Guru Prasatha,b,c, M. Chidambaramc, Bodil Reckeb, John Bagterp Jørgensena, aDepartment of Applied Mathematics and Computer Science, Technical University of Denmark, Matematiktorvet, Building 303B, DK-2800 Kgs Lyngby, Denmark bFL Automation A/S, Hø dingsvej 34, DK-2500 Valby, Denmark