Qualitative and quantitative assessment of waste generation in a refrigerator-manufacturing plant based on a waste tree and mass balance

In this study, wastes originating at each production station during refrigerator manufacturing were identified and classified based on a waste tree. A mass balance study revealed a total waste production factor of 0.046 kg/kg of a product of which 75.3%, 23.9%, and 0.8% were non-hazardous wastes (NHWs), packaging wastes (PWs), and hazardous wastes (HWs), respectively. Wastes produced during refrigerator manufacturing were grouped under 35 different waste codes. Waste codes that contributed more than 5% by weight were 15 02 02 (contaminated absorbent material), 15 01 10 (contaminated packaging), 16 02 13 (electronic cards), 07 02 14 (polyol) and 08 05 01 (isocyanates), 19 08 13 (treatment sludge), 16 02 15 (capacitors), and 13 01 13 (hydraulic oil) for HWs, 12 01 01 (ferrous metal), and 16 02 16 (components) for NHWs, and, finally, 15 01 03 (wooden), 15 01 01 (paper&cardboard), and 15 01 02 (plastic) for PWs over 5 years. Scrap costs were used as a surrogate to determine production stages that generated high amounts of metal and plastic wastes. Logarithmically, increasing and decreasing trends were observed for PWs and NHWs over the study period, respectively. HW amounts did not exhibit a statistically significant trend. Twenty-eight BATs (best available techniques) were identified that could be applied in refrigerator manufacturing for waste minimization and management. Among those, 8 of them were proposed for further improvement for waste management in the facility.