Improving The Structure Of The Wet-type Desulphurization Tower And Optimizing The Operation Conditions

Wet-type desulfurization（H₂S）technique has been widely used in coal chemical industry.Nowadays,the industrially applicable packed desulfurization tower has many advantages,such as big mass transfer area,high desulfurization efficiency,low cost and so on.However,with the expansion of enterprise production scale the increased consumption of high sulfur coal,and the upgrade of desulfurization standard,some drawbacks have been exposed on the usage of the packed tower.Especially for the desulfurization tower with big size,nonuniform distribution of gas and liquid occurs commonly,and the elemental sulfur which produced by the mass transfer absorption reaction is easily accumulated on the filler surface and the corner of the tower bottom,thus resulting in the block-up of the packed tower,decreasing the desulfurization efficiency,and finally bringing negative effect on practical production.In order to solving these problems,researchers have proposed some specific solutions and ideas,such as using the structured packing to replace the random packing,combining the filler and plate,and optimizing the technological conditions of desulfurization.At present,it is a very significant subject to solve the blocking problem of the packed tower by improving the structure of desulfurization tower and optimizing the concreted operation conditions for a practical unit device.In this thesis,the main work is focused on analyzing the structure parameters of a wet-type desulfurization tower and the operation process conditions of an actual running device in Jilin Cornell Chemical Industry.By considering the structure characteristics of the packed tower,specific process parameters and the actual effect of desulfurization,some schemes on improving the tower structure and optimizing the process conditions were put forward.The main proposal and measures are as follows:improving the purification grade by adopting a direct contact way with the sieve tray,and increasing the rate of mass transfer by utilizing the rapid reaction principle of H₂S and alkali solution;increasing screen-aperture and superficial gas velocity;upgrading the height of the plate,and enhancing the dynamic absorption effect on gas mixing with liquid.Furthermore,the process parameters of the desulphurization were optimized by adjusting the liquid circulation and pressure drop of the tower.The actual industrial running tests showed that the problem in tower blocking can be well solved by adjusting tower structure parameters and optimizing desulfurization process conditions.The whole device runs stably for long-term with exported standard of hydrogen sulfide emission,which can certainly bring excellent economic and environmental benefits.