Seawater FGD process

There are two basic seawater FGD process concepts one uses the lutural alkalinity of the seawater to neutralize absorbed SO2 the other uses added lime. All commercial seawater FGD processes rely on the alkalinity of the hicarhonate in the seawater to neutralize the SO2... 

The absorption by the sea of SO2 released into the atmosphere from chimneys can be viewed as a particular case of flue gas desulphurization (FGD). In what follows we consider two examples of FGD processes using seawater the inertion of engine exhaust on oil tankers and the reduction of SO2 emission on coastal industrial plants. Because of its alkalinity, seawater can absorb approximately three times as much SO2 as fresh water. 

The Bischoff wet FGD process utilizes either limestone or lime as the sorbent. Bischoff s early scrubber experience was with lime and natural oxidation. With the increased demand for gypsum as the preferred byproduct and the use of sea water for at least a portion of the process water, Bischoff has evolved their wet FGD technology in the direction of limestone with forced oxidation. Limestone is the preferred sorbent when seawater is used as the process water. 

Bechtel has developed a concqitual design fin a 2S0 MW seawatm FGD plant based on their dolomitic lime FGD process as used on Montana Power s Colstrip Units 3 and 4 (Abrams et al., 1988 Shield, 1992). Magnesium hydroxide formed by the reaction of magnesium in the seawater with lime in the legenmation tanks is die primary absorbent... 

Glenna, K. and Tokerud, A. (ABB Flakt, Oslo, Norway), 1991, Unique FGD Process Uses Seawater as Absorbent—Desulfurization of Flue Gas Without Chemicals in a Norwegian Oil Refinery, ABB Review, April. 

FGD and DeNO Manual, 1988, Fiakt-Hydro Seawater Process, Mcllvaine Company, Northbrook, IL, February, pp. 210.1-210.9. 

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