10th International Aerosol Conference September 2 - September 7, 2018 America's Center Convention Complex St. Louis, Missouri, USA
Abstract View
Physical and Chemical Properties of Particulate Matter in a Chinese Electrolytic Zinc Manufacturing Facility
ZIZHEN MA, Xu Huang, Fuyuan Xu, Ge Zhang, Linhua Jiang, Jingkun Jiang, Lei Duan, Ning Duan, Tsinghua University
Abstract Number: 283 Working Group: Workplace Aerosol
Abstract China is the largest producer and consumer of refined zinc in the world. More than 80% refined zinc is produced by hydrometallurgy during which the electrolysis is a key step. During this step, large amount of particulate matter (PM) containing acid mist and heavy metals are generated because of the burst of oxygen bubbles. If not controlled properly, it can lead to significant adverse effects on atmospheric environment and on human health in surrounding area. In this study, PM characteristics in a typical Chinese electrolytic zinc manufacture facility was investigated. TSP, PM10 and PM2.5 were collected and analyzed for mass concentration and chemical compositions. We found that PM2.5 and PM10 accounted for 1.6 ~ 3.2% and 29.1 ~ 37.1% of TSP, respectively. TSP contained ~54.0% acid mist in which 47.6% was sulfuric acid and 52.4% was sulfate. The average concentration of acid mist in TSP, PM10 and PM2.5 was 1.84, 1.54, and 0.11 mg/m3, respectively. These are higher than the values set by various occupational health and safety regulations in the world. The acid mist collected was unevenly distributed in working place. It increased with the decreasing in the height above the electrolytic bath. Moreover, the acid mist above the electrolytic bath was higher than that those collected in the nearby aisles. The enrichment of acid mist in PM was observed, i.e., the percentage of SO42- in PM was more than twice the percentage of SO42- in electrolyte. The Smol/Znmol for PM2.5 samples were higher than those in PM10 and TSP samples. Zn, Mg, Mn and Al were the major metallic elements in PM samples. Some hazardous heavy metals (e.g., Pb, Cr, Sb and Cd) were found to be enriched in PM, especially in PM2.5.