Scrubber energy

Ammoniation NHi, NH4CI, S1F4, HF Cyclone, electrostatic precipitator, baghouse, high-energy scrubber... 

The electrostatic effect can be incorporated into wet scrubbing by charging the particulates and/or the scrubbing-liquor droplets. Electrostatic scrubbers may be capable of achieving the same efficiency for fine-particulate removal as is achieved by high-energy scrubbers, but at substantially lower power input. The major drawbacks are increased maintenance of electrical equipment and higher capital cost. 

Coke oven discharging (pushing) Hydrocarbons, coke dust Hoods to fans and venturi scrubbers, low-energy scrubbers followed by ESPs (may use water spray at oven outlet)... 

The continuous-spray design is ideal for any application in which there is a relatively light loading of submicron particles or condensed organics that form a submicron flame. Ordinarily, the only other piece of equipment applicable to this type of loading would be a high-energy scrubber. Since dust resistivity has no effect on the precipitator, it can be applied successfully on many very difficult dry applications. 

Particulate emissions can amount to as much as 0.25 tonne/tonne of pulp produced, particularly for an older pulp mill operating without controls (Table 15.13). Electrostatic precipitators, wet scrubbers, or occasionally both can achieve particulate containment of 95% or better [49]. The precipitator catch is returned to the black liquor stream for chemical recovery from the captured inorganic chemicals. Fumes lost from the dissolving tank vent are captured by demister pads or small low-energy scrubbers, which return the collected material to the green liquor circuit. Wet scrubbers are used for lime kiln dust containment. The waste liquor is used for slaking or other recycle functions in the lime circuit (Chap. 7), helping to decrease make-up chemical requirements and water emissions. 

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