Desulfurization Of High Sulfur Coal Research Articles

Experimental Study on Electro Chemical Catalytic Oxidation Desulfurization of High Sulfur Coal Based on Computer

Coal and other fossil energy has a greater pollution, especially in the process of its combustion will bring a variety of environmental pollution problems, such as sulfur dioxide combustion, which produces more serious air pollution. Therefore, in order to reduce coal pollution, it is necessary to carry out desulfurization treatment before coal combustion. There are many shortcomings and problems in the traditional coal desulfurization methods, mainly in secondary pollution and harsh operating environment. As a mild desulfurization and purification technology, the research value of Electrochemical Catalytic Oxidation Desulfurization (ECOD) is highlighted. Based on this, this paper first analyses the process flow and desulfurization mechanism of high sulfur coal Electrocatalytic Oxidation Desulfurization (EOD) technology, and then studies the ECOD technology of high sulfur coal, and verifies the influencing factors of ECOD of high sulfur coal.

Effect of vibration on the separation efficiency of high-sulfur coal in a compound dry separator

The direct combustion of high-sulfur coal can cause serious problems such as the formation of acid rain; therefore, the desulfurization of high-sulfur coal before combustion can reduce environmental pollution. On the basis of an analysis of raw coal, the use of a compound dry separator is proposed in this paper to separate high-sulfur coal across the full size range of 80–0mm. The effects of the vibration amplitude (A), frequency (f), and angle (θ) on the separation results were systematically analyzed in this study. The results showed that when the high-sulfur coal was separated using the compound dry separator under the optimal vibration parameters of f=38Hz, A=2.6mm, and θ=46.5°, the yields of the concentrate and tailings were 71.24% and 28.76%, respectively, with corresponding sulfur contents of 0.93% and 28.59%. The probable error (E) was 0.145 with the largest degree of sulfur content segregation. Under these separation conditions, the acceleration at a clean coal segment increased by 58.06% compared with that at a gangue area; moreover, the material stratification at the clean coal segment was apparent, and the clean coal area was the main separation area. The stratification of dense material at the gangue area was poor, and the gangue area was mainly used to transport and discharge gangue.

Mechanism Research on Electrochemical Catalytic Oxidation Desulfurization of High Sulfur Coal

Electrochemical desulfurization is a mild chemical desulfurization method. This paper introduces the electrochemical catalytic oxidation method which is used to process High Sulfur Coal samples under acidic condition. Study tells that during the processing of electrochemical catalytic oxidation desulfurization ,pyrite and organic sulfur in coal are oxidized and converted into water soluble sulfur compounds by some active oxygen and other oxidizing agent or high valence ions which are produced on the surface of electrolytic anode.After analyzing the experiments ,another conclusion that the desulfurization process is faster for the added catalyst ion also involving in the reaction is reached.

04/01735 Experimental research on enhancing desulfurization of high sulfur coal in flotation by electrochemical methods: Yang, Y. et al. Meitan Zhuanhua, 2003, 26, (2), 60–63. (In Chinese)

04/01735 Experimental research on enhancing desulfurization of high sulfur coal in flotation by electrochemical methods: Yang, Y. et al. Meitan Zhuanhua, 2003, 26, (2), 60–63. (In Chinese)

Demineralization and Desulfurization of High-Sulfur Assam Coal with Alkali Treatment

Demineralization and desulfurization of high-sulfur coal from Assam (Makum coalfield), India, was investigated using aqueous solutions of sodium hydroxide, potassium hydroxide, and their mixtures (...

Organic Desulfurization of Assam Coal and Its Sulfur-Rich Lithotypes by Sequential Solvent Extraction to Obtain Cleaner Fuel

In this paper the distribution of sulfur in different lithotypes in Assam coal is reported and an attempt is made for organic desulfurization of Assam coal by directly using original run-of-mine coal as well as by taking its sulfur-rich lithotypes, using sequential solvent extraction to obtain cleaner fuel. More than 80% organic sulfur was found to have been removed by this treatment. The vitrinite content of the coal seemed to play no significant role on the organic desulfurization of the coal and sulfur-rich lithotypes. Successive sequential extraction of coal may help in desulfurization of high sulfur coals to obtain cleaner fuels.

98/02657 Chemical-catalytic depolymerization and desulfurization of high sulfur coal with superacid catalyst (II). Catalysis by HF/BF 3: Shimizu, K. et al. DGMK Tagungsber., 1997, 9704, (Proceedings ICCS '97, Volume 3), 1349–1352.

98/02657 Chemical-catalytic depolymerization and desulfurization of high sulfur coal with superacid catalyst (II). Catalysis by HF/BF 3: Shimizu, K. et al. DGMK Tagungsber., 1997, 9704, (Proceedings ICCS '97, Volume 3), 1349–1352.

98/00939 Desulfurization of high-sulfur coal in cement kiln: Xie, J. et al. Wuhan Gongye Daxue Xuebao, 1996, 18, (2), 17–20. (in Chinese)

A sample of Tabas coal from Iran was oxidized using air, peroxyacetic acid (PAA), and PAA + air as a pretreatment for desulfurization with sodium butoxide in a batch reactor. The effects of air oxidation temperature, PAA oxidation time, sodium butoxide reaction time and temperature, solvent concentration and particle size on the reduction of sulfur were investigated. The PAA + air oxidation pretreatment was the most effective method for enhancing sulfur removal. This procedure increased pyritic sulfur removal by approximately 15% and organic sulfur removal by 20% in leaching with sodium butoxide. Increasing the temperature from 25 (unoxidized) to 100 °C on air oxidized samples, increased sulfur reduction for organic and inorganic sulfur by 7% and 11%, respectively. Further increases in temperature decreased the sulfur removal. For PAA oxidized samples that dried at room temperature, penetration of PAA into the coal pores blocked them, leading to a reduction in the diffusion of sodium butoxide. For oxidized/desulfurized samples, depending on the desulfurization conditions, the reduction in pyritic, organic and total sulfur ranged from 28% to 84%, 8% to 49% and 19% to 67%, respectively. The particle size reduction had a positive effect on the efficiency of the leaching process. For particle sizes <300 μm, after oxidation and desulfurization at 150 °C for 90 min, pyritic, organic and total sulfur decreased from 0.9%, 0.82% and 1.72% to 0.18%, 0.45% and 0.64%, a reduction of 81%, 49% and 65%, respectively. The results show that PAA + air oxidation pretreatment can be used as an effective method for enhancing the removal of organic and inorganic sulfur without severe dissolution of the coal organic matrix.

98/00938 Desulfurization of high-sulfur coal during hydropyrolysis. II. Effects of reaction parameters on desulfurization in hydropyrolysis: Chen, H. et al. Ranliao Huaxue Xuebao, 1997, 25, (5), 404–409. (in Chinese)

98/00938 Desulfurization of high-sulfur coal during hydropyrolysis. II. Effects of reaction parameters on desulfurization in hydropyrolysis: Chen, H. et al. Ranliao Huaxue Xuebao, 1997, 25, (5), 404–409. (in Chinese)

97/00774 Solubilization and desulfurization of high sulfur coal at mild condition with trifluoromethane sulfonic acid

97/00774 Solubilization and desulfurization of high sulfur coal at mild condition with trifluoromethane sulfonic acid

96/04688 Solubilization and desulfurization of high sulfur coal under mild conditions with trifluoromethanesulfonic acid

The two types of high-sulphur coals Mequinenza and Illinois No. 6, in the initial form and subjected to potassium/liquid ammonia reduction, were analysed by atmospheric pressure–temperature programmed reduction (AP–TPR) method. It has been shown that preliminary demineralisation was beneficial for AP–TPR measurements because of the removal of calcium compounds. The reduction of sulphides and disulphides in the potassium/liquid ammonia system was found to lead to formation of aromatic and aliphatic thiols. The presence of the latter is better manifested in the AP–TPR kinetograms when the measurements are performed in the presence of a special reducing mixture. It has been shown that the coal reduction in the potassium/liquid ammonia system apart from transformations of non-thiophene sulphur groups also leads to breaking up of the C–S bonds in some thiophene systems.

96/02025 Desulfurization of high sulfur coals by rapid pyrolysis with alkali treatment

96/02025 Desulfurization of high sulfur coals by rapid pyrolysis with alkali treatment

Desulfurization of High Sulfur Coals by Rapid Pyrolysis with Alkali Treatment.

Desulfurization of High Sulfur Coals by Rapid Pyrolysis with Alkali Treatment.

Evidence of the reciprocal organic matter-pyrite interactions affecting the sulfur removal during coal pyrolysis

Abstract The mutual influences of the organic matter and pyrite on the removal of sulfur during coal pyrolysis were studied. Several high-sulfur, low-rank Spanish coals with different organic and pyritic sulfur contents were pyrolysed in a swept fixed-bed reactor to temperatures up to 800 °C at 5 K min −1 . The coals and chars were demineralized with HF-HCl and examined by SEM-EDX and X-ray diffraction. A calibration curve of organic sulfur concentration vs. peak/background ratio was established for demineralized coals. The results indicated that organic sulfur tends to decrease with increasing pyrolysis temperature for coal samples containing very little or no pyrite. However, starting from 500 °C the organic sulfur content of chars from pyrite-containing coals increased, and the degree of dispersion of organic sulfur also increased with temperature. These findings indicated that H 2 S released from pyrite decomposition can be reincorporated in char as organic sulfur. The influence of the organic matter on pyrite decomposition was investigated using float-sink fractions with pyrite contents of 0.4–33 wt% and organic matter contents of 20–80 wt%. Samples with higher pyrite contents released very little sulfur as H 2 S at >630 °C, whereas samples with lower pyrite contents and hence higher organic matter contents evolved more H 2 S. SEM-EDX and XRD showed that at 600 °C and with low organic matter contents, pyrite remained practically unaltered and pyrrhotite was very scarce. At 800 °C the transformation was incomplete, resulting in a pyrite core surrounded by a pyrrhotite shell. On the other hand, with high organic matter contents, pyrite particles showed evident signs of decomposition and were almost entirely transformed into pyrrhotite at 600 °C. These results show that only partial desulfurization of high-sulfur coals can be achieved by pyrolysis, owing to organic matter-pyrite interactions.

Treatment of high-sulfur coal using selective flocculation and microbial desulfurization in a draft-tube slurry bubble column

Experiments are performed to study a novel precombustion coal cleaning process for deashing and desulfurization of high-sulfur coals. The process is based on the integration of selective flocculation and microbial desulfurization in a draft-tube slurry bubble column bioreactor (DTSB). In the process, the unique features of the selective flocculation in ash reduction is preserved. Desulfurization of the pyrite particles is subsequently achieved through oxidation of pyrite by Thiobacillus ferrooxidans in a DTSB bioreactor. Samples of Pittsburgh No. 8 seam are used to test this multistage process. In this study, the effect of bacterial adaptation on the oxidation rate of pyrite is examined. Based on the kinetic data, a reactor model for the bio-oxidation rate of pyrite is developed. This model considers the bacterial adhesion and the kinetics of direct and indirect pyrite oxidation by T. ferrooxidans.