Life Cycle Environmental Assessment of Biodegradable Packaging: Starch and Polystyrene Tray with End of Life Management

摘要

Life cycle assessment (LCA) was conducted to assess the environmental impacts of the production of two types of tray packaging materials: starch which was derived from cassava as a renewable material; and polystyrene (PS) which was petroleum-based and derived from crude oil. Two types of polystyrene,general purpose polystyrene (GPPS) and high impact polystyrene (HIPS) were considered. Life cycle inventory (LCI) data for the starch tray packaging material was collected from cassava planting,starch and tray pilot-production factories. Data on PS tray, both GPPS and HIPS were collected from the literatures and also tray production factories. Life Cycle Impact Assessment (LCIA) was done by using LCA software, SimaPro version 7.0, with the Eco-Indicator 99 method. The system boundary for the process was set to include raw material extraction, manufacturing and transportation and excluded the end of life management. The functional unit of this LCA was defined as 1,000 units of 20 x 14 x 1.5 cm tray. The environmental impact level was quantified in unit of Person-equivalent ("Pt"). The results showed that the cassava starch tray has 10.2 Pt. higher impact than polystyrene tray. The LCA results of starch tray show that electricity used in tray production phase had the highest environmental impact and followed by cassava starch production phase. The results also illustrated to the weak points that should be improved to increase environmental efficiency.The options proposed were to focus on large scale of tray production (1,000 pieces per hour); and product designed changes to reduce the material required by 15% with the large scale of production. The implementation of those options would reduce the environmental impact of the starch tray process by 9% and 43%,respectively.The second part of research is using LCA to evaluate final waste treatment of the different type of packaging materials. The environmental impact of waste treatment for cassava starch tray by composting method is the lowest and for polystyrene tray the land filling waste treatment is the lowest impact.Ongoing implementation of tray forming and cassava starch production technologies would further reduce the environmental impact and result in starch trays being a more environmentally friendly type of packaging.