[Emission Characteristics and Emission Factors of Volatile Organic Compounds from E-waste Dismantling and Recycling Processes]

Huan Jing Ke Xue. 2022 Jan 8;43(1):150-159. doi: 10.13227/j.hjkx.202104137.
[Article in Chinese]

Abstract

A large number of volatile organic compounds (VOCs) are emitted from the high temperature treatment process in the dismantling and recycling procedure of e-wastes, which has a significant impact on the surrounding environment and human health. In this study, an e-waste dismantling and recycling yard was selected to measure the VOCs concentrations and compositions in the exhaust of treatment facilities of heating baking board, plastic granulation, wet extraction, and pyrometallurgical workshops, and the emission characteristics of VOCs and emission factors for total VOCs from different production processes were investigated. The results showed that there were significant differences in total VOCs emission concentrations among different production processes. The concentrations of total VOCs produced in different workshops followed the descending order of the heating baking board (heating rotary plate furnace) process[(2096.1±732.4) μg·m-3] > plastic granulation process[(1639.1±538.5) μg·m-3] > heating baking board (electric heater) process[(625.3±535.5) μg·m-3] > pyrometallurgical process[(436.8±305.2) μg·m-3] > wet extraction process[(271.3±73.1) μg·m-3]. The compositions of VOCs emitted from different production processes were also clearly different; however, the major components of VOCs were generally oxygenated compounds and aromatic hydrocarbons. The specific component characteristics were as follows:the dominant groups of VOCs emitted from the heating baking board process (including heating rotary plate furnaces and electric heaters) were oxygenated compounds and aromatic hydrocarbons, accounting for 74.1%-79.7% of the total. The main components of VOCs emitted from the pelletizing process were aromatic hydrocarbons and oxygenated compounds, accounting for 71.8% of the total. Oxygenated compounds and aromatic hydrocarbons, which contributed equally, were also the main groups of VOCs discharged by the wet extraction process, and the sum proportion of the two groups was 84.2%. Halogenated hydrocarbon was the dominant group of VOCs from the pyrometallurgical process, accounting for 92.1% of the sum of VOCs. There was a substantial divergence in the total VOCs emission factors of different production processes. The ranking of the mean values of emission factors of total VOCs was as follows:the heating baking board (electric heater) process (297.0 g·t-1) > plastic granulation process (29.5 g·t-1) > wet extraction process (25.4 g·t-1) > heating baking board (heating rotary plate furnace) process (25.2 g·t-1) > pyrometallurgical process (1.9 g·t-1). Therefore, the main VOCs emission processes of the e-waste centralized dismantling and recycling industry were the heating baking board process and plastic granulation process.

Keywords: E-waste dismantling and recycling; emission characteristics; emission factors; organized emission; volatile organic compounds (VOCs).

MeSH terms

  • Air Pollutants* / analysis
  • Electronic Waste*
  • Environmental Monitoring
  • Humans
  • Plastics
  • Recycling
  • Volatile Organic Compounds* / analysis

Substances

  • Air Pollutants
  • Plastics
  • Volatile Organic Compounds