Aiming at issues on flue gas des-ulfurization facing coal-fired power plants inChina, such as process selection, whetheradopting flue gas desulfurization (FGD) or not,qualification of flue gas desulfurization en-ginee...Aiming at issues on flue gas des-ulfurization facing coal-fired power plants inChina, such as process selection, whetheradopting flue gas desulfurization (FGD) or not,qualification of flue gas desulfurization en-gineering company, the localization of technicalequipment, charge for SO2 emission andnormalized management, this article makes acomprehensive analysis and puts forwardconstructive suggestions. These will providesome references for those being engaged in fluegas desulfurization in coal-fired power plants.[展开更多
To lower the cost of bauxite electrolysis desulfurization using NaOH solution as the supporting electrolyte, effects of electrolyte recycling on bauxite electrolysis desulfurization were investigated. The results in...To lower the cost of bauxite electrolysis desulfurization using NaOH solution as the supporting electrolyte, effects of electrolyte recycling on bauxite electrolysis desulfurization were investigated. The results indicate that electrode corrosion, cell voltage, the desulfurization rate and the pH value of the electrolyte have no obvious changes with the increase of cycle times. Additionally, there were some transitive valence S-containing ions in electrolyte after the electrolysis, such as SO3^2-,S2O3^2- . However, most of the sulfur in bauxite was eventually oxidized into SO4^2- into the electrolyte, and these S-containing ions did not affect the recycling utilization for electrolyte.展开更多
The optimum conditions for sulfur removal from coal by electrochemical reduction flotation in an aqueous NaCl solution were determined from orthogonal experiments. The effect of electrolytic conditions on the desulfur...The optimum conditions for sulfur removal from coal by electrochemical reduction flotation in an aqueous NaCl solution were determined from orthogonal experiments. The effect of electrolytic conditions on the desulfurization ratio was also studied. The electrochemical-reduction processed coal was examined by X-ray diffraction, Fourier transform infrared spectroscopy and wet chemical analysis. The results show that electrochemical reduction converts hydrophobic pyrite in Nantong coal into hydrophilic FeS and S2- and leads to an increase in the concentration of hydroxyl groups and aliphatic moieties and a corresponding decrease in carboxyl and carbonyl groups, which enhances the flotation desulfurization of the coal.展开更多
The effect of removing pyrite and ash ffom fine coal with electrostatic separator is determined by the electric property of coal, the distribution of corona ion and etectrostatic field, and the disperse and even feed....The effect of removing pyrite and ash ffom fine coal with electrostatic separator is determined by the electric property of coal, the distribution of corona ion and etectrostatic field, and the disperse and even feed. The dielectric constant of coal and mineral matter is studied in this paper and the amendment has been made to survey theory. The oscillogram is adopted to study the distribution of corona ion and electrostatic field.The paper details the study of remoing pyrite and ash from fine coal, and the test results demonstrate the high efficiency of removing pyrite and ash with electrostatic separator.展开更多
Influence of factors such as potential of electrolyte, electrolyzing time, concentration of electrolyte, and pH value on flotation and desulfurization of coal was researched. The result shows that the electrochemical ...Influence of factors such as potential of electrolyte, electrolyzing time, concentration of electrolyte, and pH value on flotation and desulfurization of coal was researched. The result shows that the electrochemical reduction can enhance the desulfurization effect and increase the yield of clean coal under certain conditions. So it is an effective method.展开更多
Problems in desulfurization of coal by electrochemical reduction is analyzed and calculated. The result shows that 1 ) the △rGm function of the reaction of pyrite into FeS and the modifying reaction decreasing the ox...Problems in desulfurization of coal by electrochemical reduction is analyzed and calculated. The result shows that 1 ) the △rGm function of the reaction of pyrite into FeS and the modifying reaction decreasing the oxygenous functions on coal surface is smaller than zero in a spontaneous reaction, and greater than zero in a non-spontaneous reaction; 2) the △rGm value can be adjusted by pH and the dosage of electrolyte to make it be greaterthan zero , which is favorable for the modifying reaction and useful for desulfurization of coal. The research has provided a theoretical foundation for determining reasonable technical parameters of desulfurization。展开更多
Through analyzing the proportion of SO2 emission from thermal power plants in the nationwide SO2 emis- sion in USA, Japan etc. developed countries, and the developmental course of thermal power installed capacity and ...Through analyzing the proportion of SO2 emission from thermal power plants in the nationwide SO2 emis- sion in USA, Japan etc. developed countries, and the developmental course of thermal power installed capacity and the FGD capacity in USA, the FGD capacity of thermal power plants in China is forecasted from two angles. One is to predict FGD capacity in accordance with the policy in force in China. The other is to predict FGD capacity based upon the emission right trading policy. As compared, it is held that FGD equipment should be mainly installed on the large size units burning high sulfur coal according to the emission right trading policy. Such a method of work not only can economize large amount of investments and operation costs, but also can realize the same environmental effect.展开更多
The kinetics for hydrogen(H)adsorption on Ir(111)electrode has been studied in both HClO_(4) and H_(2)SO_(4) solutions by impedance spectroscopy.In HClO_(4),the adsorption rate for H adsorption on Ir(111)increases fro...The kinetics for hydrogen(H)adsorption on Ir(111)electrode has been studied in both HClO_(4) and H_(2)SO_(4) solutions by impedance spectroscopy.In HClO_(4),the adsorption rate for H adsorption on Ir(111)increases from 1.74×10^(-8)mol·cm^(-2)·s^(-1) to 3.47×10^(-7)mol·cm^(-2)·s^(-1) with the decrease of the applied potential from 0.2 V to 0.1 V(vs.RHE),which is ca.one to two orders of magnitude slower than that on Pt(111)under otherwise identical condition.This is explained by the stronger binding of water to Ir(111),which needs a higher barrier to reorient during the under potential deposition of H from hydronium within the hydrogen bonded water network.In H_(2)SO_(4),the adsorption potential is ca.200 mV negatively shifted,accompanied by a decrease of adsorption rate by up to one order of magnitude,which is explained by the hindrance of the strongly adsorbed sulfate/bisulfate on Ir(111).Our results demonstrate that under electrochemical environment,H adsorption is strongly affected by the accompanying displacement and reorientation of water molecules that initially stay close to the electrode surface.展开更多
The utilization of coal derived pyrite by electrolysis was studied. It is obvious that the sulfur and Fe in pyrite can be electrolyzed into Fe 3+ and SO 2- 4, and the no pollutant is drained off. In this paper, the in...The utilization of coal derived pyrite by electrolysis was studied. It is obvious that the sulfur and Fe in pyrite can be electrolyzed into Fe 3+ and SO 2- 4, and the no pollutant is drained off. In this paper, the influence of conditions, including electrolysis potential, time, temperature, the acidity of electrolysis solutions, the concentration of adding agent, the concentration of pyrite, and the rate of conversion of pyrite (Cr) was investigated. Cr increases with the rise of potential, time, temperature, acidity and the concentration of additive agent, but decreases with the rise of concentration of pyrite. At the certain conditions (at the potential of 3 0 V, temperature of 298 K, time of 12 h, the concentration of MnSO 4 of 6%, concentration of pyrite of 4%, and concentration of acid of 10%), Cr is high to 93%. In the same time, the mechanism of electrolysis of pyrite was provided. The electrolysis of pyrite is actually the recycle of Mn ion between anodic surface and pyrite. At last, the production of FeSO 4·7H 2O through electrolysis of pyrite was introduced.展开更多
A new electrochemical reactor with rotating cylindrical electrodes was designed and used to increase the regeneration efficiency of chelated iron desulfurization solution.The influence of operating parameters,such as ...A new electrochemical reactor with rotating cylindrical electrodes was designed and used to increase the regeneration efficiency of chelated iron desulfurization solution.The influence of operating parameters,such as the rotation speed of electrode,voltage,and inlet air and liquid flow rates,on the regeneration rate was investigated.Compared with the traditional tank-type reactor,the regeneration rate with the new electrochemical reactor was increased significantly.Under the optimum conditions,the regeneration rate was increased from 45.3%to 84.8%.Experimental results of continuous operation indicated that the new electrochemical regeneration method had some merits including higher regeneration efficiency,smaller equipment size and good stability in operation.展开更多
We prepared an SbSn intermetallic compound powder with a mixture of equal molar amounts of antimony (Sb) and tin (Sn) by melt-annealing and high-energy ball milling, and characterized the obtained substance with X...We prepared an SbSn intermetallic compound powder with a mixture of equal molar amounts of antimony (Sb) and tin (Sn) by melt-annealing and high-energy ball milling, and characterized the obtained substance with XRD (X-ray diffraction), DSC (differential scanning calorimetry), SEM (scanning electron microscopy), and XPS (X-ray photoelectron spectroscopy). The prepared SbSn has a hexagonal structure with a melting point of 425 ℃. The particles have a dendritic appearance in micromorphology images. More Sb atoms are enriched on the surface than Sn atoms. A desulfurization efficiency of up to 33.92% can be obtained when applying this powder as a medium in the electric desulfurization of crude oil under the following conditions an emulsion with a volumetric ratio of water to oil at 20:80, a surfactant mass fraction in the emulsion of 0.18%, a processing time of 17 h, and a voltage of 9.68 V. SbSn could be a promising catalyst for desulfurizing crude oil. The desulfurization performance is ascribed to the electron cavities formed by current induction.展开更多
This paper introduces present state of industrialization development in flue gas desulfuration, including technological selection, state of design and contracting capability, localization of equipment, etc. in China. ...This paper introduces present state of industrialization development in flue gas desulfuration, including technological selection, state of design and contracting capability, localization of equipment, etc. in China. It points out main problems currently existed and presents proposals on promotion of desulfuration technology with selfowned intellectual property right, perfection of demonstrative projects and pushing forward localization of desulfuration equipment.展开更多
The Ontario Hydro Method (OHM) recommended by the United States Environmental Protection Agency (EPA) was used to determine mercury speciation in the combustion flue gas across wet FGD systems. Four coal-fired uni...The Ontario Hydro Method (OHM) recommended by the United States Environmental Protection Agency (EPA) was used to determine mercury speciation in the combustion flue gas across wet FGD systems. Four coal-fired units with wet FGD systems were chosen to evaluate mercury speciation and mercury removal efficiencies through these wet FGD systems. Chlorine content in coal had been suggested as a main factor that affects mercury speciation in flue gas. It is shown that the higher the chlorine concentration in coal is, the higher the percentage of oxidized mercury (Hg2+) is removed in wet FGD systems, which can increase overall mercury removal efficiencies through wet FGD systems. The selective catalyst reduction (SCR) system has a function of oxidizing ele- mental mercury (Hg0) to oxidized mercury. A higher percentage of oxidized mercury in the total vapor mercury at the FGD inlet is observed when SCR is in service. Therefore, higher overall mercury removal efficiencies through wet FGD are attained. Because of different wet FGD operating conditions, there are different mercury removal efficiencies in different units. Elemental mercury reemission took place when a fraction of oxidized mercury absorbed in the slurry is reduced to elemental mercury, and Hg2+ is reemitted from stack, which results in decreases in mercury removal efficiencies through wet FGD systems.展开更多
Oxidative desulfurization (ODS) of Azeri crude oil was studied under the electric field.By means of orthogonal experiments,the optimum conditions for desulfurization of crude oil were identified,while the effect of ox...Oxidative desulfurization (ODS) of Azeri crude oil was studied under the electric field.By means of orthogonal experiments,the optimum conditions for desulfurization of crude oil were identified,while the effect of oxidative desulfurization under the electric field was compared with that of the single oxidative desulfurization method.The test results showed that the desulfurization reaction taking place under the electric field would be better than the traditional method.The desulfurization rate of crude oil could reach up to 77.06% at 115 ℃ at a distilled water amount of 10 m%,a desulfurizer dosage of 200 μg/g,and a demulsifier dosage of 50 μg/g.展开更多
文摘Aiming at issues on flue gas des-ulfurization facing coal-fired power plants inChina, such as process selection, whetheradopting flue gas desulfurization (FGD) or not,qualification of flue gas desulfurization en-gineering company, the localization of technicalequipment, charge for SO2 emission andnormalized management, this article makes acomprehensive analysis and puts forwardconstructive suggestions. These will providesome references for those being engaged in fluegas desulfurization in coal-fired power plants.[
基金Projects(51004090,51474198)supported by the National Natural Science Foundation of ChinaProject(KF13-03)supported by State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingProject(2015036)supported by Youth Innovation Promotion Association,Chinese Academy of Sciences
文摘To lower the cost of bauxite electrolysis desulfurization using NaOH solution as the supporting electrolyte, effects of electrolyte recycling on bauxite electrolysis desulfurization were investigated. The results indicate that electrode corrosion, cell voltage, the desulfurization rate and the pH value of the electrolyte have no obvious changes with the increase of cycle times. Additionally, there were some transitive valence S-containing ions in electrolyte after the electrolysis, such as SO3^2-,S2O3^2- . However, most of the sulfur in bauxite was eventually oxidized into SO4^2- into the electrolyte, and these S-containing ions did not affect the recycling utilization for electrolyte.
基金supported by the Special Fund for Major State Basic Research Program of China (Project 2004CB217601).
文摘The optimum conditions for sulfur removal from coal by electrochemical reduction flotation in an aqueous NaCl solution were determined from orthogonal experiments. The effect of electrolytic conditions on the desulfurization ratio was also studied. The electrochemical-reduction processed coal was examined by X-ray diffraction, Fourier transform infrared spectroscopy and wet chemical analysis. The results show that electrochemical reduction converts hydrophobic pyrite in Nantong coal into hydrophilic FeS and S2- and leads to an increase in the concentration of hydroxyl groups and aliphatic moieties and a corresponding decrease in carboxyl and carbonyl groups, which enhances the flotation desulfurization of the coal.
文摘The effect of removing pyrite and ash ffom fine coal with electrostatic separator is determined by the electric property of coal, the distribution of corona ion and etectrostatic field, and the disperse and even feed. The dielectric constant of coal and mineral matter is studied in this paper and the amendment has been made to survey theory. The oscillogram is adopted to study the distribution of corona ion and electrostatic field.The paper details the study of remoing pyrite and ash from fine coal, and the test results demonstrate the high efficiency of removing pyrite and ash with electrostatic separator.
基金The National Natural Science F oundation of China ( 5 0 1740 5 4)
文摘Influence of factors such as potential of electrolyte, electrolyzing time, concentration of electrolyte, and pH value on flotation and desulfurization of coal was researched. The result shows that the electrochemical reduction can enhance the desulfurization effect and increase the yield of clean coal under certain conditions. So it is an effective method.
基金National Natural Science Foundation of China(50174054)
文摘Problems in desulfurization of coal by electrochemical reduction is analyzed and calculated. The result shows that 1 ) the △rGm function of the reaction of pyrite into FeS and the modifying reaction decreasing the oxygenous functions on coal surface is smaller than zero in a spontaneous reaction, and greater than zero in a non-spontaneous reaction; 2) the △rGm value can be adjusted by pH and the dosage of electrolyte to make it be greaterthan zero , which is favorable for the modifying reaction and useful for desulfurization of coal. The research has provided a theoretical foundation for determining reasonable technical parameters of desulfurization。
文摘Through analyzing the proportion of SO2 emission from thermal power plants in the nationwide SO2 emis- sion in USA, Japan etc. developed countries, and the developmental course of thermal power installed capacity and the FGD capacity in USA, the FGD capacity of thermal power plants in China is forecasted from two angles. One is to predict FGD capacity in accordance with the policy in force in China. The other is to predict FGD capacity based upon the emission right trading policy. As compared, it is held that FGD equipment should be mainly installed on the large size units burning high sulfur coal according to the emission right trading policy. Such a method of work not only can economize large amount of investments and operation costs, but also can realize the same environmental effect.
基金supported by the National Natural Science Foundation of China(No.91545124,No.21972131,No.21832004).
文摘The kinetics for hydrogen(H)adsorption on Ir(111)electrode has been studied in both HClO_(4) and H_(2)SO_(4) solutions by impedance spectroscopy.In HClO_(4),the adsorption rate for H adsorption on Ir(111)increases from 1.74×10^(-8)mol·cm^(-2)·s^(-1) to 3.47×10^(-7)mol·cm^(-2)·s^(-1) with the decrease of the applied potential from 0.2 V to 0.1 V(vs.RHE),which is ca.one to two orders of magnitude slower than that on Pt(111)under otherwise identical condition.This is explained by the stronger binding of water to Ir(111),which needs a higher barrier to reorient during the under potential deposition of H from hydronium within the hydrogen bonded water network.In H_(2)SO_(4),the adsorption potential is ca.200 mV negatively shifted,accompanied by a decrease of adsorption rate by up to one order of magnitude,which is explained by the hindrance of the strongly adsorbed sulfate/bisulfate on Ir(111).Our results demonstrate that under electrochemical environment,H adsorption is strongly affected by the accompanying displacement and reorientation of water molecules that initially stay close to the electrode surface.
文摘The utilization of coal derived pyrite by electrolysis was studied. It is obvious that the sulfur and Fe in pyrite can be electrolyzed into Fe 3+ and SO 2- 4, and the no pollutant is drained off. In this paper, the influence of conditions, including electrolysis potential, time, temperature, the acidity of electrolysis solutions, the concentration of adding agent, the concentration of pyrite, and the rate of conversion of pyrite (Cr) was investigated. Cr increases with the rise of potential, time, temperature, acidity and the concentration of additive agent, but decreases with the rise of concentration of pyrite. At the certain conditions (at the potential of 3 0 V, temperature of 298 K, time of 12 h, the concentration of MnSO 4 of 6%, concentration of pyrite of 4%, and concentration of acid of 10%), Cr is high to 93%. In the same time, the mechanism of electrolysis of pyrite was provided. The electrolysis of pyrite is actually the recycle of Mn ion between anodic surface and pyrite. At last, the production of FeSO 4·7H 2O through electrolysis of pyrite was introduced.
基金Supported by the National Natural Science Foundation of China(21376229)the Excellent Innovation Projects of Postgraduates of Shanxi Province(20103084)the Science and Technology Innovation Projects of Shanxi Province Colleges and Universities(2013128)
文摘A new electrochemical reactor with rotating cylindrical electrodes was designed and used to increase the regeneration efficiency of chelated iron desulfurization solution.The influence of operating parameters,such as the rotation speed of electrode,voltage,and inlet air and liquid flow rates,on the regeneration rate was investigated.Compared with the traditional tank-type reactor,the regeneration rate with the new electrochemical reactor was increased significantly.Under the optimum conditions,the regeneration rate was increased from 45.3%to 84.8%.Experimental results of continuous operation indicated that the new electrochemical regeneration method had some merits including higher regeneration efficiency,smaller equipment size and good stability in operation.
文摘We prepared an SbSn intermetallic compound powder with a mixture of equal molar amounts of antimony (Sb) and tin (Sn) by melt-annealing and high-energy ball milling, and characterized the obtained substance with XRD (X-ray diffraction), DSC (differential scanning calorimetry), SEM (scanning electron microscopy), and XPS (X-ray photoelectron spectroscopy). The prepared SbSn has a hexagonal structure with a melting point of 425 ℃. The particles have a dendritic appearance in micromorphology images. More Sb atoms are enriched on the surface than Sn atoms. A desulfurization efficiency of up to 33.92% can be obtained when applying this powder as a medium in the electric desulfurization of crude oil under the following conditions an emulsion with a volumetric ratio of water to oil at 20:80, a surfactant mass fraction in the emulsion of 0.18%, a processing time of 17 h, and a voltage of 9.68 V. SbSn could be a promising catalyst for desulfurizing crude oil. The desulfurization performance is ascribed to the electron cavities formed by current induction.
文摘This paper introduces present state of industrialization development in flue gas desulfuration, including technological selection, state of design and contracting capability, localization of equipment, etc. in China. It points out main problems currently existed and presents proposals on promotion of desulfuration technology with selfowned intellectual property right, perfection of demonstrative projects and pushing forward localization of desulfuration equipment.
文摘The Ontario Hydro Method (OHM) recommended by the United States Environmental Protection Agency (EPA) was used to determine mercury speciation in the combustion flue gas across wet FGD systems. Four coal-fired units with wet FGD systems were chosen to evaluate mercury speciation and mercury removal efficiencies through these wet FGD systems. Chlorine content in coal had been suggested as a main factor that affects mercury speciation in flue gas. It is shown that the higher the chlorine concentration in coal is, the higher the percentage of oxidized mercury (Hg2+) is removed in wet FGD systems, which can increase overall mercury removal efficiencies through wet FGD systems. The selective catalyst reduction (SCR) system has a function of oxidizing ele- mental mercury (Hg0) to oxidized mercury. A higher percentage of oxidized mercury in the total vapor mercury at the FGD inlet is observed when SCR is in service. Therefore, higher overall mercury removal efficiencies through wet FGD are attained. Because of different wet FGD operating conditions, there are different mercury removal efficiencies in different units. Elemental mercury reemission took place when a fraction of oxidized mercury absorbed in the slurry is reduced to elemental mercury, and Hg2+ is reemitted from stack, which results in decreases in mercury removal efficiencies through wet FGD systems.
基金financial supports from the Science and Technology Office of Liaoning Province (Project number:2008403001)the Liaoning Provincial Office of Education for Innovation Team (Project number:2009T002)
文摘Oxidative desulfurization (ODS) of Azeri crude oil was studied under the electric field.By means of orthogonal experiments,the optimum conditions for desulfurization of crude oil were identified,while the effect of oxidative desulfurization under the electric field was compared with that of the single oxidative desulfurization method.The test results showed that the desulfurization reaction taking place under the electric field would be better than the traditional method.The desulfurization rate of crude oil could reach up to 77.06% at 115 ℃ at a distilled water amount of 10 m%,a desulfurizer dosage of 200 μg/g,and a demulsifier dosage of 50 μg/g.