Sodium-based flue gas desulfurization sludge disposal ponds. Final report

Technical Report · Fri Apr 01 04:00:00 EST 1994

OSTI ID:10160488

Ainsworth, C C; Rai, D; Smith, S C; Felmy, A R; Amonette, J E; Resch, C T ^[1]

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1. Battelle Pacific Northwest Lab., Richland, WA (United States)

Two flue gas desulfurization (FGD) sludge disposal ponds, each receiving sludge from a different sodium (Na)-based FGD scrubbing system, at a subbituminous coal-fired power plant were investigated. Samples of pond and pore waters, and sludge solids from selected ponds were obtained to characterize pond biogeochemistry to identify common or distinguishing reactions that affect disposal of FGD sludge and to evaluate possible causes for the different H{sub 2}S{sub (g)} emissions observed for the two pond systems. Very high levels of total dissolved solids characterized both Na-based FGD scrubber material used, the biogeochemistry of the sludge disposal ponds is very similar, and certain biogeochemical reactions are generic to controlling the leachate chemistry of FGD ponds. Dissimilatory microbial SO{sub 4}{sup 2{minus}} reduction to sulfide is present in both ponds and reacts with various solution-phase heavy metals (e.g., Cd, Cu, Fe, Ni, Pb, and Zn) to form low-solubility sulfide minerals, and hence, aqueous concentrations of these metals are at or near the analytical detection limits. The H{sub 2}S{sub (g)} emissions result from H{sub 2}S{sub (g)} generation in the sediments and diffusion up through the water column. Oxidation of H{sub 2}S{sub (g)} as it migrates up the water column is dependent on (1) the chemical oxygen demand of the pond waters, (2) the pH and hence speciation of the H{sub 2}S, (3) the depth of the water, and (4) the temperature and salinity of the water.

• Research Organization: Electric Power Research Inst., Palo Alto, CA (United States); Battelle Pacific Northwest Lab., Richland, WA (United States)
• Sponsoring Organization: Electric Power Research Inst., Palo Alto, CA (United States)
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 10160488
• Report Number(s): EPRI-TR--103915; ON: UN94013847
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010800
20 FOSSIL-FUELED POWER PLANTS
200202
CADMIUM
COPPER
DESULFURIZATION
ELEMENTS
EPRI
FLUE GAS
FOSSIL-FUEL POWER PLANTS
IRON
LEAD
NICKEL
NOXIOUS GAS AND PARTICULATE EMISSIONS
PONDS
SCRUBBERS
SLUDGES
SULFATE-REDUCING BACTERIA
SULFIDES
TRACE AMOUNTS
WASTE DISPOSAL
WASTE MANAGEMENT
ZINC