Oxidant scrubbers

CLINSULF DO [Direct oxidation] A process for recovering sulfur from gas streams containing low concentrations of hydrogen sulfide, under conditions where the conventional Claus process is not applicable. It can recover sulfur over a wider range than direct oxidation scrubbers. Operated in Austria and South Korea. 

In an effort to resolve some of the questions relating to the effectiveness of the oxidant scrubbers in various air masses, we have recently developed a new oxidant scrubber based on the aqueous chemistry of iodide. At neutral pH, excess aqueous iodide reacts with a variety of oxidants according to the net reaction ... 

Figure 1. Recovery of DMS standards added to atmospheric samples using various oxidant scrubbers. (A) 0.4g NajCC /Chromasorb in oceanic air with low ozone concentrations (O) 0.4g Na2C03/Chromasorb in oceanic air with intermediate ozone levels ( ) 0.4g (a) and l-5g ( ) Na2CC>3/Chromasorb in continental air with ozone concentrations of 55-65 ppb. (B) 0.4g Anakrom/ NaoCXDi in oceanic (v) and continental (A) air neutral aqueous KI in oceanic ( ) ana continental (O) air.

Burchfield and his associates (12, 13, 14) reported a procedure involving reductive pyrolysis of the effluent gases whereby compounds containing chlorine, sulfur, or phosphorus form HCl, H2S, or PH3, respectively. By using an aluminum oxide scrubber following the pyrolysis stage, the system was specific for phosphorus. However, the detection system appears to be inferior to other available detectors for phosphorus and will probably have little or no use for this purpose. 

Scrubbers are pollution control devices, which remove pollutants from gas streams, particularly from the combustion gases produced by facilities such as coal-fired power plants. Scrubbers may use absorbents in slurry or solution form (wet scrubbers), or in powder form (dry scrubbers), with wet scrubbers being more often used. Modern scrubbers can consist of several cleaning steps such as dust separation, sulfur removal, capture of mercury, lead, or other heavy metals, and breakdown of nitrogen oxides. Scrubbers of the future will also need to capture and sequester carbon dioxide. Currently, the most common application of scrubbers is still the removal of sulfur, frequently combined with capture of fly-ash. 

Capture of mercury in the sludge from a sulfur oxide scrubber. 

Fig. 6 Magnesium oxide regeneration and sulfur dioxide recovery section for a magnesium oxide scrubber. (From Ref.. )...

Kittler, P., Swan, H., andirvey, J., An indicating oxidant scrubber for the measurement of atmospheric dimethylsulfide, Armoj. Environ., 26A, 2661-2664, 1992. 

Other approaches and devices (thermal or catalytic oxidation, scrubbers, precipitation, and particulate filters) have been evaluated for general treatment of fugitive emissions of solvent. Some have proven useful in specific cases. But adsorption into activated carbon remains the standard treatment method to be used as a "black hole."... 

Both Andreae et al(1983c) and Saltzman and Cooper (1988) observed oxidant scrubber failure during sampling in polluted... 

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