Abstract
ABSTRACTMercury, being bound with metal concentrate, is released to atmosphere in the smelting process, and has adverse effects on surrounding ambient air quality and public health. In this study, based on literature and field investigations, onsite measurements of mercury emissions to the atmosphere for four large-scale gold smelters were estimated. Almost all of the atmospheric mercury released from the roasting pretreatment process occurred before acid plants. All the concentrations of mercury emitted from the four tested gold smelters were much lower than the emission standard of air pollutants for GB 9078–1996 Grade II level areas of 1000 µg m–3. The speciation of Hgp took up the largest proportions for the total mercury concentrations. Because of using high mercury oxidation efficiency of double-conversion double absorption (DCDA) technology, the proportions of Hg2+ in the exhaust flue gas was higher than Hg0. Average emission factors of atmospheric mercury for these four tested gold smelters were calculated to be 1.7 kg of Hg per ton gold produced, and the national total amount of mercury emitted from large-scale gold smelting industry in the year of 2014 was estimated to 639.9 kg. However, mercury emission factors obtained from present study were much lower than that in previous research. Thus, with the exact emission factor obtaining from more specific field-test data and the detailed activity data information about gold smelting industry, an accurate inventory of mercury emissions to the atmosphere from large-scale gold smelters in China can be updated in the future.
Highlights
Mercury (Hg) has become one of the most widelyviewed global environmental pollution problems, because of its persistence, mobility and high bioaccumulation in the environment
With the exact emission factor obtaining from more specific field-test data and the detailed activity data information about gold smelting industry, an accurate inventory of mercury emissions to the atmosphere from large-scale gold smelters in China can be updated in the future
This paper focuses on the current atmospheric mercury emission situation and the mercury speciation distribution in flue gas associated with large-scale gold smelting industry of China
Summary
Mercury (Hg) has become one of the most widelyviewed global environmental pollution problems, because of its persistence, mobility and high bioaccumulation in the environment. There are three types of mercury speciation, including elemental gaseous mercury (Hg0), oxidized gaseous mercury (Hg2+), and particle-bound mercury (HgP). Three forms of mercury in the atmosphere can experience a complicated interchangeable process. In the process of photochemical reaction, Hg0 can be oxidized to Hg2+ by some strong oxidizing substances, such as ozone, hydrogen peroxide, halogen, etc. Hg0 and Hg2+ are adsorbed by aerosol and formed HgP. Previous study found that Hg0 could transport for very long distance, participate in global mercury cycle, and stay in the atmosphere for a long time. The deposition of Hgp generally occurred in the vicinity of the emission sources (Liu and Luo, 2012)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
