A Cross-flow Rotating Bed Towards Desulfurization Of Exhaust Gas Of Ships

With the development of economic globalization,shipping plays an important role in foreign trade.The combustion of fuel oil by ships and warships produces a large amount exhaust gas contained SO2,which has a serious impact on the environment and human health.In order to meet the desulfurization standard proposed by IMO,more and more attention has been paid to develop novel devices and technology towards process intensification for purifying exhaust gas.In view of the difference of desulfurization on ships and on land,a new cross-flow rotating bed reactor towards desulfurization of exhaust gas of ships was proposed in this paper.The device uses double-layer hydrophobic wire mesh to disperse liquid,which can contact with gas in a cross-flow mode.It has the advantages of small floor area,simple structure and easy to be reformed in pipeline.This paper firstly studies the structure and main parameters of the new cross-flow rotating bed.For the discharge standards and characteristic requirements of different sea areas(open seas and coastal ports),the characteristics of open seawater and closed alkali desulfurization were studied experimentally.The effects of operating parameters,absorbent characteristics,and reactor effective height on desulfurization efficiency and gas phase mass transfer coefficient(Kya)were investigated.Based on the experimental results,the Kya correlation between open seawater desulfurization and closed alkali desulfurization was determined.Using the correlation method,the effective height of the reactor for predicting the discharge of the ship's exhaust gas is predicted,and the experimental verification is carried out.The results show that Kya can reach 1.8 kmol/(m3s)in open seawater desulfurization,and the desulfurization efficiency can reach 86%,which meets the high seas emission requirements.Kya can reach 3.0 kmol/(m3s)in closed alkali desulfurization,and the desulfurization efficiency can reach 97%,which basically meets the coastal port emission standards.Compared with other desulfurization reactors,the Kya value of the new cross-flow rotating bed is 2-10 times of that of other reactors,and its volume is 1/100-1/20 of that of other reactors,which has great potential for application in ship desulfurization.