ABSTRACT
Many modern processes are reasonably complex and have multiple output characteristics. For example, a heat treatment process like induction hardening needs to be executed to meet the requirements on surface hardness and case depth. The performance of the pulp cooking process can be unsatisfactory due to the presence of assignable causes. To check whether the pulp cooking process is in statistical control, control charts are constructed for the pulp yield and viscosity. A lot of research has been carried out in the field of simultaneous optimization of multiple characteristics. The optimum setting of the factors that would increase the pulp yield as much as possible without increasing the viscosity beyond 52 is identified by formulating the problem as a constraint optimization problem. Through discussions with technical professionals, three factors, namely, percentage of sulfidity in the cooking medium, percentage of black liquor in the cooking medium, and cooking time are selected for the study.
