Effective recycle planning for construction and demolition wastes.

摘要

Construction and Demolition (C&D) wastes are materials produced in the process of construction, renovation, or demolition of structures (buildings and roads). It also includes materials generated as a result of natural disasters (EPA, 2009 A). Preliminary estimates from the U.S. Environmental Protection Agency (EPA) show that the nation generated more than 160 million tons of building related C&D wastes in 2003. Also, Pennsylvania Department of Environmental Protection (PADEP) estimated that in 2005, Pennsylvania disposed over 2.25 million tons of C&D wastes in its municipal and C&D landfills (PADEP, 2009 A). Though previous studies have shown that it is cost-effective and environmentally friendly for contractors or construction managers to recycle C&D wastes rather than disposing them in landfills, these previous studies, however, paid little or no attention to detailed cost of recycling C&D wastes in a particular geographical area or region as compared to the availability of market for recycled materials or monetary value of the recycled materials.;Hence, the objective of this study was to develop a mathematical model that helps stakeholders in construction business to evaluate the potential cost of recycling C&D waste components in their geographical area or region, and the potential revenue from the recycled materials. The model developed in this thesis will enable private companies or individuals to identify, invest and participate in the recycling of C&D waste components that yield good profits in their region or area. It will also enable Government to identify, sponsor or provide incentives for the recycling of C&D waste components that yield no or less profit in order to reduce environmental pollution and generate jobs.;A case study is conducted in Pennsylvania to test the model developed in this thesis and the test has been successful. Based on the mathematical model and logic structure for selecting C&D waste components for recycling, drywall, roofing shingles and wood are identified as the components whose recycling will yield good profit and thus may not need government's support or incentives. Moreover, C&D waste components such as concrete, brick, block and asphalt, have been identified as components whose recycling will not be profitable enough and therefore would require government's support or incentives. The result of the case study also shows that the quantity of non-ferrous metals in C&D wastes are very small and their recycling will not yield any significant profit.