Ultralow Level Mercury Treatment Using Chemical Reduction and Air Stripping: Scoping Report

Looney, B.B.

Savannah River Site (S.C.)

关键词: Stripping;    Reduction;    Ground Water;    Remedial Action;    Mercury;   

DOI  :  10.2172/760274
RP-ID  :  WSRC-RP-2000-00697
RP-ID  :  AC09-96SR18500
RP-ID  :  760274

美国|英语

来源: UNT Digital Library

【 摘 要 】

Data collected during the first stage of a Savannah River Technology Center (SRTC) Strategic Research and Development Project confirmed the efficacy of chemical reduction and air stripping/sparging as an ultralow level mercury treatment concept for waters containing Hg(II). The process consists of dosing the water with low levels of stannous chloride to convert the mercury to Hg. This form of mercury can easily be removed from the water by air stripping or sparging. Samples of Savannah River Site (SRS) groundwater containing approximately 130 ng/L of total mercury (as Hg(II)) were used for the study. In undosed samples, sparging removed 0 percent of the initial mercury. In the dosed samples, all of the removals were greater than 94 percent, except in one water type at one dose. This sample, which was saturated with dissolved oxygen, showed a 63 percent reduction in mercury following treatment at the lowest dose. Following dosing at minimally effective levels and sparging, treated water contained less than 10 ng/L total mercury. In general, the data indicate that the reduction of mercury is highly favored and that stannous chloride reagent efficiently targets the Hg(II) contaminant in the presence of competing reactions. Based on the results, the authors estimated that the costs of implementing and operating an ultralow level mercury treatment process based on chemical reduction and stripping/sparging are 10 percent to 20 percent of traditional treatment technologies.