Experimental study on mercury release behavior and speciation during pyrolysis of two different coals

✍ Scribed by Ling LIU; Yu-feng DUAN; Yun-jun WANG; Hui WANG; Jian-jun YIN

• Publisher: Elsevier
• Year: 2010
• Tongue: Chinese
• Weight: 260 KB
• Volume: 38
• Category: Article
• ISSN: 1872-5813
• DOI: 10.1016/s1872-5813(10)60026-6

✦ Synopsis

Mercury release behavior and speciation during pyrolysis of Datong and Baorixile coals were studied in a temperature-programmed tube furnace under N 2 atmosphere. The results showed that mercury emission from coal pyrolysis significantly depended on temperature. The ratio of Hg release in coal increased dramatically with increasing temperatures, and more than 92% mercury was released at 600°C. Elemental mercury was the dominant species in the gaseous mercury during coal pyrolysis.

The percentage of Hg 0 of Datong coal increased first, and then decreased, while it reduced gradually for Baorixile coal. Both the rate of Hg release and the percentage of Hg 0 rose finitely through the time ranging from 0 to 60 min, and Baorixile coal displayed more significant increase than Datong coal. Higher heating rate promoted the mercury release in coal and enhanced the proportion of Hg 2+ in gas; especially for Baorixile coal it reached 19.5%, being apparently higher than that for Datong coal.