Reducing Lean and Environmental Wastes: The Integration of Value Stream Mapping with Environmental Wastes to Improve Production, Performance, Efficiency and Process Flow
Thesis DisciplineMechanical Engineering
Degree GrantorUniversity of Canterbury
Degree NameMasters of Engineering
Current concepts of environmental waste focus on the total production of waste from a production plant or industrial setting and the subsequent consequences on the natural environment. Hence, there is an emphasis on containing waste within the industrial boundaries and applying a post-production process to clean it up. However, waste is generated by individual processes within the production system and can be more effectively treated at this individual site level. Therefore, focused management of environmental waste reduction requires that production engineers first know what the environmental waste is and where specifically it is being generated. However, this is often simply not known with any accuracy. In addition, production plants are controlled and improved by lean methods. Current environmental waste methods lack integration with lean methods and thus are not included in the continuous improvement cycles. Consequently, there is a need to include environmental waste impacts alongside the other primary lean wastes. This work develops just such an integrative method which includes both environmental waste and Value Stream Mapping (VSM). This method was developed and tested in a re-manufacturing setting (i.e. Christchurch Engine Centre, Pratt and Whitney) and is able to represent a variety of environmental wastes. Specifically, it integrates aspects from the generic environmental standard ISO14001 through to an organisational environmental risk register. It provides integration within the VSM process which ensures that the established lean improvement programme (through the use of Kaizen improvements) is focused on specific environmental improvement actions. While the example for this thesis used the factors of carbon footprinting, perceived impact, costs to remediate and waste volumes (both removed from process and residual); the method is capable of being generalised to nth dimension environmental factors. It is thus able to represent a customised environmental waste index for any particular industry. Ambiguous user estimation of waste quantities was accommodated through PERT beta distributions. Several ways to represent the multi-dimensional environmental waste impact data were explored via industry focus group reviews and the preferred representation was designed to completion. The resulting method can be used by production staff to quantify and represent environmental impacts at the level of the individual processes and aggregated to report wastes for the whole value stream. The method may also be used by executives to align organisational practices with strategic objectives for waste reduction.