Scrubber electric power demand

Figure 4. Effect of adipic acid concentration on gross electric power demand for 90% SOi removal in TCA scrubber.

Figure 5. Gross electric power demand of limestone scrubbers using hot (300°F)...

The gross electric energy demands of the three types of limestone scrubbers are compared in Table III as percentages of the total plant power production. The comparison is based on 2420 cfm per MW (saturated flue gas at 125°F, 1 atm) and 70 percent fan efficiency. In no case does the electric demand for 90 percent S02 removal exceed 0.83 percent of production. It is interesting to note that the differential between the highest demand (spray tower) and the lowest demand (TCA) amounts to only 0.16 percent of the total plant power production. From this viewpoint, the simplicity and increased reliability of the spray tower are not expensive attributes in terms of additional energy drain. 

The gross electric energy demand of a spray tower is greater than that of a TCA, mainly due to the higher efficiency of fans relative to slurry pumps. The difference between the two scrubber types, however, amounts to only about 0.16 percent of the generated power. 

Adipic acid can reduce the electric demand for 90 percent SO2 removal in a TCA scrubber by 30 percent at a concentration of 1400 ppm. It sets a ceiling on the power demand at 2.4 percent of plant power production at a higher demand, the value of the power saved exceeds the cost of the additive. 

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