Development Of The Wet Desulfurization Process In Slurry Bed Without The Addition Of Alkali

Researches on the removal of hydrogen sulfide have always been a hot spot over the past years,and a large number of research results have been reported,including wet desulfurization,dry desulfurization and biological desulfurization.But most desulfurization methods have different problems in practical applications.Because of its high sulfur capacity and good regeneration performance,hydroxyl-ferric oxide has caused people's great attention.However,hydroxyl-ferric oxide desulfurization agent has been applied only in the form of a fixed bed since it was developed.Fixed bed has many difficulties in the replacement of the catalyst,the process of which will make a great threat to the health of the workers.Some desulfurization processes in fixed bed will appear sulfur blocking problem.Most of the wet desulfurization process also used lye,which not only makes the equipment alkali-corrosion,but also causes secondary pollution.So it can be a good solution to these problems if the hydrogen sulfide can be removed in the form of slurry bed by making good use of hydroxyl-ferric oxide.In this paper,hydroxyl-ferric oxide was synthesized by the way of neutralization oxidation through the reaction between ferrous sulfate and sodium carbonate.Hydroxyl-ferric oxide with better desulfurization performance was synthesized by adjusting the temperature,pH value and concentration of ferrous sulfate ions.Hydroxyl-ferric oxide with high activity was prepared in the concentration of 1 mol / L,temperature of 60 ?,pH value of 8 and aging for 3 hours.Sulfur capacity could reach 103 mg H₂ S /g desulfurization agent after three hours of reaction.The selected samples were ?-FeOOH with high specific surface and mesoporous structure which were characterized by XRD,IR,SEM,TEM and desorption of nitrogen.Secondly,the desulfurization effect of hydroxyl iron oxide in the slurry reactor was investigated in this paper.The factors such as slurry solid content,apparent gas velocity,initial concentration of hydrogen sulfide and temperature were studied to investigate their effects on the performance of desulfurization.The conclusions are as follows: in the experimental range,the content of slurry solid,hydrogen sulfide concentration and temperature have great influence on the desulfurization of the system,and the effect of apparent gas velocity is less.The adaptive temperature for desulfurization system is 30 and it is suitable for the treatment of lower concentrations of hydrogen sulfide gas.?The desulfurization rate of the bed can be up to 95% under the appropriate conditions.Hydrogen peroxide regeneration and air regeneration can be a good performance for desulfurization agent regeneration and the former method has a great advantage in reducing the regeneration time.The performance of desulfurization agent is still maintained at 93% or more under 5 times recyclings.The production of high valence sulfur is main reason for the performance's decrease of the desulfurization agent in this two regeneration methods.Finally,the extraction separation of sulfur using o-xylene in this system was studied.From experiments we found that o-xylene could separate the sulfur in the system and the sulfur separation rate was above 97% under the conditions at the temperature of 65 ?,the extraction time of 70 min,and the liquid-solid ratio of 15: 1.