Volatility of Arsenic and Lead from Simulated Incinerator Slags

Abstract

Experiments were conducted on arsenic and lead volatility from simulated slags containing either arsenic or lead. Samples were exposed to temperatures up to 900 C and atmospheres that were inert, oxidizing, reducing, or contained hydrogen chloride. Both arsenic and lead deposited within the system during the experiment, requiring a cleaning procedure to remove and capture the metal for measurement. Arsenic or lead volatility increased with increasing treatment time, temperature, and CO concentration. Lead volatility also increased with increasing HC1 concentration. The arsenic volatilized was two orders of magnitude less than lead for the same experimental conditions. The results show that under conditions similarly occurring in a hazardous waste incinerator, arsenic in a slag is relatively involatile, and only a small fraction of either arsenic or lead is volatilized.

Volatility of Arsenic in Contaminated Clay at High Temperatures

“…Gases from cylinders were metered through rotameters and mixed in a manifold to produce the desired atmosphere as described by Overcamp et al (1999). The gases flowed into a vertical tube furnace heated to the desired temperature.…”

“…The end caps could be removed to allow insertion and removal of the clay sample and the glass wool filter during the run. The tube's downstream end had an annular quench zone similar to that used by Overcamp et al (1999). A 38-mm o.d.…”

“…A cleaning cycle similar to the one used by Overcamp et al (1999) was used then to desorb and recover any arsenic that had sorbed to the walls of the tubes. At the conclusion of this procedure, the glass wool filter was removed and stored in a Ziploc ® bag.…”

“…Overcamp et al (1999) reported on the volatility of arsenic in a slag-like matrix. Waterland et al (1991) performed pilot-scale tests at the EPA Incineration Research Facility.…”

“…In a related study on the volatilization of arsenic and lead from simulated incinerator slags, Overcamp et al (1999) reviewed the literature on metal volatilization in incineration. This paper focuses on the behavior of arsenic in soils treated by incineration or other high-temperature processes.…”