DOI: http://dx.doi.org/10.1065/lca2004.09.180.7
Goal, Scope and Background. Green Productivity (GP) is a newparadigm in sustainable manufacturing where resource conservationand waste minimization constitute the strategy in simultaneouslyenhancing environmental performance and productivity.This productivity approach to the sustainability of industriesrequires the adoption of clean production technology and thedevelopment of appropriate indicators and instruments to measureenvironmental performance in a continuous improvementstrategy that focuses on the manufacturing stage of the productlife cycle. The analysis may be expanded to include the entirelife cycle with increasing details on impacts, improvement strategiesand indicators.
Methods. The study proposes a methodology for GP assessmentthat integrates the essential components of life cycle assessment(LCA) and multicriteria decision analysis specifically the analytichierarchy process (AHP). LCA provides a systematic andholistic perspective for GP analysis that spans inventory, impactand improvement assessment. The AHP is utilized as a decisionframework and valuation tool for impact and improvement assessmentto come up with priority weights. Indicators are derivedand measured from a streamlined LCA focused on a numberof parameters within the gate-to-gate analysis to demonstratethe GP concept in relation to resource utilization and waste minimization.An input-output approach using a suitable materialbalance in a scenario analysis provides the basis of GP performancemeasurement.
Results and Conclusion. The diagnostic model is applied on asemiconductor assembly/packaging operation. From the streamlinedlife cycle inventory, impact factors were derived for waterresource depletion (WRD), energy resource depletion (ERD),human toxicity-air (HTA), human toxicity-land (HTL), humantoxicity-water (HTW), aquatic ecotoxicity (ETA) and terrestrialecotoxicity (ETT). Valuation of impact factors using the AHPshowed the high significance of ETT, HTL, WRD and ERD.This especially reflects the impact of the industry on the solidwaste problem as a result of emissions to land associated withhuman toxicity and ecotoxicity effects and the intensive use ofwater and energy resources. Using scenario analysis, the effectof implementing a process-based improvement technique on aproduct-specific operation was determined and the highest valuesin GP are for energy utilization, water utilization and terrestrialecotoxicity.
Recommendation and Perspective. Expert system technology wasexplored in developing a diagnostic prototype that emulates howhuman experts diagnose green productivity of manufacturingprocesses. The aim was to investigate how such a diagnosis couldbe performed in an intelligent fashion that it is also easily accessibleas a decision support for industries. The expert systemmodel will provide flexibility in testing the relationships of environmentalperformance and productivity parameters as wellas in preserving and disseminating valuable human expertise inGP program implementation. This is a continuing research effortthat is building the knowledge base for GP assessment. Itwill include case studies over a wider range or level of detailregarding the impacts and improvement techniques and the otherstages of the product life cycle. |
