Qingbin Song

Environmental effects of heavy metals derived from the e-waste recycling activities in China: a systematic review.

As the worlds leading manufacturing country, China has become the largest dumping ground for e-waste, resulting in serious pollution of heavy metals in China. This study reviews recent studies on environmental effects of heavy metals from the e-waste recycling sites in China, especially Taizhou, Guiyu, and Longtang. The intensive uncontrolled processing of e-waste in China has resulted in the release of large amounts of heavy metals in the local environment, and caused high concentrations of metals to be present in the surrounding air, dust, soils, sediments and plants. Though the pollution of many heavy metals was investigated in the relevant researches, the four kinds of heavy metals (Cu, Pb, Cd and Cr) from e-waste recycling processes attracted more attention. The exceedance of various national and international standards imposed negative effects to the environment, which made the local residents face with the serious heavy metal exposure. In order to protect the environment and human health, there is an urgent need to control and monitor the informal e-waste recycling operations.

Measuring treatment costs of typical waste electrical and electronic equipment: A pre-research for Chinese policy making

Waste Electrical and Electronic Equipment (WEEE) volume is increasing, worldwide. In 2011, the Chinese government issued new regulations on WEEE recycling and disposal, establishing a WEEE treatment subsidy funded by a levy on producers of electrical and electronic equipment. In order to evaluate WEEE recycling treatment costs and revenue possibilities under the new regulations, and to propose suggestions for cost-effective WEEE management, a comprehensive revenue-expenditure model (REM), were established for this study, including 7 types of costs, 4 types of fees, and one type of revenue. Since TV sets dominated the volume of WEEE treated from 2013 to 2014, with a contribution rate of 87.3%, TV sets were taken as a representative case. Results showed that the treatment cost varied from 46.4RMB/unit to 82.5RMB/unit, with a treatment quantity of 130,000 units to 1,200,000 units per year in China. Collection cost accounted for the largest portion (about 70.0%), while taxes and fees (about 11.0 %) and labor cost (about 7.0 %) contributed less. The average costs for disposal, sales, and taxes had no influence on treatment quantity (TQ). TQ might have an adverse effect on average labor and management costs; while average collection and purchase fees, and financing costs, would vary with purchase price, and the average sales fees and taxes would vary with the sales of dismantled materials and other recycled products. Recycling enterprises could reduce their costs by setting up online and offline collection platforms, cooperating with individual collectors, creating door-to-door collection channels, improving production efficiency and reducing administrative expenditures. The government could provide economic incentives-such as subsidies, low-cost loans, tax cuts and credits-and could also raise public awareness of waste management and environmental protection, in order to capture some of the WEEE currently discarded into the general waste stream. Foreign companies with advanced WEEE utilization technology could invest or participate in this area, producing profits for themselves while helping to develop and implement environmentally friendly and energy-saving technologies applicable to the Chinese market.

Lead recovery from scrap cathode ray tube funnel glass by hydrothermal sulphidisation

This research focused on the application of the hydrothermal sulphidisation method to separate lead from scrap cathode ray tube funnel glass. Prior to hydrothermal treatment, the cathode ray tube funnel glass was pretreated by mechanical activation. Under hydrothermal conditions, hydroxyl ions (OH–) were generated through an ion exchange reaction between metal ions in mechanically activated funnel glass and water, to accelerate sulphur disproportionation; no additional alkaline compound was needed. Lead contained in funnel glass was converted to lead sulphide with high efficiency. Temperature had a significant effect on the sulphidisation rate of lead in funnel glass, which increased from 25% to 90% as the temperature increased from 100 °C to 300 °C. A sulphidisation rate of 100% was achieved at a duration of 8 h at 300 °C. This process of mechanical activation and hydrothermal sulphidisation is efficient and promising for the treatment of leaded glass.

Characterization of brominated flame retardants from e-waste components in China

Many studies show that high levels of many toxic metals and persistent and bio-accumulative chemicals have been found in electronic waste (e-waste) dismantling sites and their surrounding environmental media. Both flame-retardant plastic housing materials and printed circuit boards (PCBs) could be the major contributors. However, relatively little work has focused on the use or content of toxic substances and their changing in scrap housing materials and PCBs from home appliances. This study evaluated the existence of brominated flame retardants (BFRs, including polybrominated diphenyl ethers (PBDEs) and Tetrabromobisphenol-A (TBBPA)) in housing plastics and PCBs from home appliances collected from various e-waste recyclers in China. These were then analyzed for the potential migration of BFRs from the e-waste components into their recycled products. The results show that both PBDEs and TBBPA were found with high level in most of e-waste samples, indicating that the widespread use of BFRs in home appliances are entering into the end-of-life stage. For the plastics samples, CRT TVs and LCD monitors should be given priority for the control of BFRs. Regarding PBDEs, the dominant congeners of BDE-209 in the plastics samples contributed 90.72-93.54% to the total concentrations of PBDEs, yet there are large variations for PCBs samples: BDE-28, -47, -99, and -153 were also important congeners compositions, except for BDE-209. Compared with previous studies, the BFRs concentrations in current Chinese e-waste are trending to decline. This study also found that BFRs in housing plastics and PCBs will be transferred into the recycled products with other purpose use, and the new products could have highly enriched capacities for BFRs. The obtained results could be helpful to manage e-waste and their components properly in order to minimize associated environmental and health risks of BFRs, particularly for their further reuse.