Advanced Gasification Mercury/Trace Metal Control with Monolith Traps

Musich, Mark ; Swanson, Michael ; Dunham, Grant ; Stanislowski, Joshua

University of North Dakota. Energy and Environmental Research Center.

关键词: 10 Synthetic Fuels;   

DOI  :  10.2172/989755
RP-ID  :  DOE/NT42461
RP-ID  :  FC26-05NT42461
RP-ID  :  989755

美国|英语

来源: UNT Digital Library

【 摘 要 】

Two Corning monoliths and a non-carbon-based material have been identified as potential additives for mercury capture in syngas at temperatures above 400°F and pressure of 600 psig. A new Corning monolith formulation, GR-F1-2189, described as an active sample appeared to be the best monolith tested to date. The Corning SR Liquid monolith concept continues to be a strong candidate for mercury capture. Both monolith types allowed mercury reduction to below 5-μg/m{sup 3} (~5 ppb), a current U.S. Department of Energy (DOE) goal for trace metal control. Preparation methods for formulating the SR Liquid monolith impacted the ability of the monolith to capture mercury. The Energy & Environmental Research Center (EERC)-prepared Noncarbon Sorbents 1 and 2 appeared to offer potential for sustained and significant reduction of mercury concentration in the simulated fuel gas. The Noncarbon Sorbent 1 allowed sustained mercury reduction to below 5-μg/m{sup 3} (~5 ppb). The non-carbon-based sorbent appeared to offer the potential for regeneration, that is, desorption of mercury by temperature swing (using nitrogen and steam at temperatures above where adsorption takes place). A Corning cordierite monolith treated with a Group IB metal offered limited potential as a mercury sorbent. However, a Corning carbon-based monolith containing prereduced metallic species similar to those found on the noncarbon sorbents did not exhibit significant or sustained mercury reduction. EERC sorbents prepared with Group IB and IIB selenide appeared to have some promise for mercury capture. Unfortunately, these sorbents also released Se, as was evidenced by the measurement of H2Se in the effluent gas. All sorbents tested with arsine or hydrogen selenide, including Corning monoliths and the Group IB and IIB metal-based materials, showed an ability to capture arsine or hydrogen selenide at 400°F and 600 psig. Based on current testing, the noncarbon metal-based sorbents appear to be the most effective arsine and hydrogen selenide sorbents. The noncarbon sorbent was able to reduce the concentration to 0 ppb from a starting concentration of 120 ppb. This compares to the target value of 5 ppb (~17μg/m{sup 3}). The EERC-prepared metal-based pellet and coprecipitate sorbents exhibited arsine reductions of 90% or greater, being below 10 ppb. Corning SR Liquid monoliths exhibited brief periods (<1 hour) of attaining 90% arsine reduction but were able to achieve greater than 80% reduction for several hours. With respect to hydrogen selenide, all Group IB and IIB metal-based sorbents tested exhibited 100% reduction from an inlet concentration of approximately 400 ppb. Corning SR Liquid monoliths exhibited an 82% reduction when two monoliths were tested simultaneously in series.