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Show Although the 1990 Clean Air Act (CAA) did not modify the NSPS, it requires that emissions of NOx be cut by 2 million to 4 million tons 'annually, starting in 1992. Power plants, municipal and industrial incinerators, and other high temperature devices will need to remove the NOx from flue gases in order to comply with federal CAA and potentially more stringent local regulations. Although there are a number of commercial technologies that can reduce NOx in flue gases by about 50 to 70%, theyare .expensive and require major equipment modifications. There are no commercial processes that can conveniently scrub out NOx along with other undesirable pollutants. Consequently, a laboratory research program was started to test the potential of sodium chlorite to oxidize and absorb NO from gas streams that simulate the composition of incinerator effluents. The objective of the scrubbing tests were to: * * Determine the potential of NaCl02 aqueous scrubbing for NO oxidation and absorption. Obtain design parameters for controlling NO with sodium chlorite. EXPERIMENTAL PROGRAM The basic scrubbing apparatus consisted of a flue gas blending system,' a 'matched 'pair of gas scrubbers and an analytical train. The blending system was capable of producing a mixture of nitrogen, oxygen, nitric oxide and nitrogen dioxide in order to simulate a wide variety 'of flue gaseous compositions by mixing pure gases components and blends in different proportions. The synthetic flue gas was introduced into the scrubber through a polyethylene sparger. The effluent gases were carried to the gas analyzers for the determination of residual NO, N02 and 02. The scrubber consisted of a 5.1 cm diameter by 61 cm long pyrex pipe capped on both ends with 0.63 cm polyethylene tubes carrying the gaseous mixtures. FLUE GAS BLENDING SYSTEM The flue gas blending system mixed the desired gases from high pressure gas cylinders. The blending system was constructed out of 0.63 cm diameter (0.0.) by 60 cm long stainless steel type 316 tubing. Each component gas was delivered through a 0.32 cm (0.0.) teflon tubing to a calibrated rotameter to the blending mainfold. The total flow rate from the blending system ranged from 8.9 to 0.4 standard liters per minute. A schematic of the gas blending system is illustrated in Figure 1. SCRUBBING VESSELS The flue gas scrubbers were 5.1 cm in diameter by 61 cm long Pyrex glass columns with a polyethylene sparger located at the bottom. The flue gas was introduced into the scrubbing solution 3 |