Mechanism Of Desulphurization Research Articles

Desulphurization mechanism and engineering practice of carbide slag.

In order to give full play to the alkaline neutralization value of carbide slag and reduce the environmental hazards of carbide slag, it is of great practical significance to study the resource utilization of carbide slag. The adsorption of sulfur compounds on carbide slag was studied in the laboratory, and the process parameters of carbide slag desulfurization were explored and optimized. The specific surface area, pore distribution, and other physicochemical parameters were analyzed by XRD and SEM, which explained the changes of products and carbide slag before and after desulfurization. The test results show that carbide slag and limestone have almost the same desulfurization effect. The kinetics of carbide slag desulfurization process conforms to pseudo-first-order kinetics, and the sulfur content of calcium carbide slag reaches to 1000 mgSO2·g-1. A project demonstration was carried out in the gold smelting Tielu Plant of Zhenyuan Huashuo Precious Metals Development Co., Ltd., in Yunnan. The results of the 2-year demonstration project showed that the desulphurization efficiency of the four-stage series desulphurization tower exceeds 95%. The concentration of sulfur dioxide in the discharged flue gas is reduced to less than 20mg·m-3, which meets the requirements of ultra-low emission standard in China. Therefore, whether from theoretical research or engineering practice analysis, it is feasible to replace limestone with calcium carbide slag for flue gas desulfurization. The paper also discusses the problems existing in the demonstration project, and provides a new idea of "using waste to treat waste" in order to solve the problem of carbide slag disposal.

A Desulphurization Mathmatical Model for Single Snorkel Refining Furnace

With an increasing demand for high grade electric magnetic steels, SSRF(Single Snorkel Refining Furance) has got much attention due to its high efficiency of both decarburization and desulphurization. However the desulphurization mechanism of this kind SSRF is remarkably different from that of other steel refining processes such as LF,RH etc. , so it is necessary to understand the behaviour of desulphurization clearly. A mathmatical model has been established in this paper to investigate the degree of desulpurization with time on the basis of the influencing factors such as sulphur capacity of flux ,stirring energy of molten steel. It is shown that the desulpurization rate constant is about 1.0E-8 in accordance with the data from the practical test of a steel plant with SSRF.

Molecular dynamics simulation of desulfurization by ionic liquids

AbstractIonic liquids (ILs) have shown an excellent performance for removing the sulfur compounds of fuel. In this work, molecular dynamic simulations were performed to screen suitable IL instead of the traditional method which is inefficient. DBT and DBTO2 were used as model compounds to study the mechanism of desulphurization. An all‐atom force field was proposed for dibenzothiophene (DBT) and dibenzothiophene 5,5‐dioxide (DBTO2). The calculated results are in good agreement with the experimental value. We investigated the interaction between the model compounds and a series of ILs composed of 1‐alkyl‐3‐methylimidazolium cations ([Cnmim]+, n = 4, 6, 8, 10) and BF, PF anions. We found that the interaction between hydrogen atoms in imidazolium ring and oxygen atoms in DBTO2 is stronger than that of sulfur atoms in DBT, and it means that DBTO2 is extracted by ILs more easily than DBT. In this work, we also compared and discussed the desulphurization mechanism as a function of different ILs, sulfur contents, temperatures, and inclusion of water or not. The above results may help us design extractant and improve the operating conditions. © 2010 American Institute of Chemical Engineers AIChE J, 56: 2983–2996, 2010

Sorption and transport behavior of gasoline components in polyethylene glycol membranes

Desulphurization mechanism of polyethylene glycol (PEG) membranes has been investigated by the study of solubility and diffusion behavior of typical gasoline components through PEG membranes with various crosslinking degrees. The sorption, diffusion and permeation coefficients were calculated by the systematic studies of dynamic sorption curves of gasoline components such as thiophene, n-heptane, cyclohexane, cyclohexene and toluene in PEG membranes. Furthermore, the temperature dependence of diffusion and solubility coefficients and the influence of crosslinking degree on sorption and diffusion behaviors were conducted to elucidate the mass-transfer mechanism. According to the discussions on dynamic sorption curves, transport mode, activation energy and thermodynamic parameters, thiophene species were the preferential permeation components. Crosslinking is an effective modification way to improve the overall performance of PEG membranes applied in gasoline desulphurization. The pervaporation (PV) and gas chromatography (GC) experiments results corresponded to the conclusions. All these investigations will provide helpful suggestions for the newly emerged membrane desulphurization technology and complex organic mixture separation by pervaporation.

Desulphurization of coal via low temperature atmospheric alkaline oxidation

Different from other options which usually required strict conditions, a method combining atmospheric oxidization and chemical cleaning with alkali solutions was employed to desulphur coals at temperature around 90 °C. The data show that 66% organic sulphur, 44% sulphide sulphur, and 15% pyrite sulphur were lost when the coal was treated in 0.25 M NaOH at 90 °C, while the solution being aerated at the flow rate of 0.136 m 3 h −1. The rate increased to 73% for organic sulphur, 83% for sulphide sulphur and 84% for pyrite sulphur when the previous coal was further treated in acidic solution containing HCl at pH 1 for another hour. The mechanism of desulphurization was explored using inductively coupled plasma mass spectrometry, X-ray photoelectron spectroscopy and infrared. It was found out that the bond of –C S was broken by atmospheric oxygen in basic environment, leading to the lost of organic sulphur in coal. Scanning electron microscope data show that the physical structure of the coal was not adversely affected by the treatment and thermogravimetric analysis results prove that the pyrolysis behavior remained unchanged, indicating that the burning process of the coal would not be adversely affected. Unlike other oxidizing methods, this technique does not lower the heating value of the coal which was manifested by relevant data.

揺動鉄浴における脱硫機構の研究

揺動鉄浴における脱硫機構の研究