Quality improvement in the chemical process industry using Six Sigma technique

Abstract Although Six Sigma has been so successful in many organizations, the successful applications of Six Sigma are rare for the chemical processes due to highly nonlinear causality. This paper provides a successful case for the chemical process industry in which degraded quality has been improved by performing the proposed Six Sigma strategy. The strategy consists of required techniques in each phase and the techniques include not only existing tools such as 5M1E approach, partial least squares (PLS), and design of experiment (DOE) but also a new methodology to discover exact key sources of quality degradation. This case study has been a great success; from 3.5 initial sigma to 5.5 sigma has been achieved by applying the proposed methodology to the quality degradation problem.