Effect of sulfur removal on scale adhesion to PWA 1480

1995 ◽  
Vol 26 (2) ◽  
pp. 427-435 ◽  
Author(s):  
J. L. Smialek ◽  
B. K. Tubbs
1991 ◽  
Vol 22 (3) ◽  
pp. 739-752 ◽  
Author(s):  
James L. Smialek

Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 245
Author(s):  
Toyohisa Fujita ◽  
Taichi Aoki ◽  
Josiane Ponou ◽  
Gjergj Dodbiba ◽  
Chunlin He ◽  
...  

This study investigated the removal of sulfur and iron from shungite rocks through different methods after fine grinding: flotation, magnetic separation, microwave treatment, and chemical leaching. In this work, first, a mineralogical study of shungite was conducted. The carbon, silica, iron, and sulfur compositions in the as-received shungite were 45.4%, 38.3%, 4.6%, and 2.4%, respectively. In flotation, a sulfur grade of 1.4% was obtained. In the wet high-gradient magnetic separation at a magnetic flux density of 1 tesla, the iron and sulfur grades in the nonmagnetic fraction were 2.8% and 1.9%, respectively. Furthermore, the sulfur reduced to 0.2% by the 9 min microwave irradiation. In addition, chemical leaching using chelating reagents and inorganic acids was utilized to remove iron and sulfur. Nitrilotriacetic acid (NTA) could reduce the iron and sulfur grades to 2.0% and 0.9%, respectively. For leaching using reverse aqua regia, the iron and sulfur grades were reduced to 0.9% and 0.23%, respectively. For leaching using a 6N HCl with H2O2 aqueous solution, the iron and sulfur grades were reduced to 0.8% and 0.34%, respectively. Overall, chemical leaching using HCl with H2O2 was the most effective for iron and sulfur removal from shungite.


2007 ◽  
Vol 46 (9) ◽  
pp. 2735-2740 ◽  
Author(s):  
Do Heui Kim ◽  
Ya-Huei Chin ◽  
George Muntean ◽  
Aleksey Yezerets ◽  
Neal Currier ◽  
...  

2015 ◽  
Vol 1107 ◽  
pp. 341-346
Author(s):  
Wan Nazwanie Wan Abdullah ◽  
Rusmidah Ali ◽  
Wan Azelee Wan Abu Bakar

Due to the low specifications for sulfur content in diesel, a lot of research work are been conducted to develop alternative method for desulfurization. Catalytic oxidative desulfurization (Cat-ODS) has been found to be an alternative method to replace a conventional method which is hydrodesulfurization.New catalyst formulation using tert-butyl hydroperoxide polymolybdate based catalyst system was investigated in this research utilizing tert-butyl hydroperoxide (TBHP) as oxidant and dimethylformamide (DMF) as solvent for extraction. A series of polymolybdate supported alumina catalysts were prepared using wet impregnation method, ageing at ambient room temperature for 24 hours and followed by calcination process. A commercial diesel with 440 ppmw of total sulfur was employed to evaluate the elimination of sulfur compounds. Besides, the percentage of sulfur removal was measured by gas chromatography-flame photometric detector (GC-FPD). The sulfur content in commercial diesel was successfully reduced from 440 ppmw to 35 ppmw under mild condition followed by solvent extraction. From catalytic testing, Mo-Al2O3 calcined at 500°C was revealed as the most potential catalyst which gave 92% of sulfur removal.


2003 ◽  
Vol 37 (17) ◽  
pp. 319A-320A ◽  
Author(s):  
Britt E. Erickson
Keyword(s):  

2021 ◽  
Vol 52 (2) ◽  
pp. 590-593
Author(s):  
Liushun Wu ◽  
Kunlong Liu ◽  
Wei Xu ◽  
Jue Wang ◽  
Haichuan Wang ◽  
...  

2021 ◽  
Author(s):  
Chourouk Romdhani ◽  
Zahrah Alhalili ◽  
Soumaya Elarbaoui ◽  
Moez Smiri

Abstract Thiols represent a source of environmental pollution especially wastewater. The present work aims to evaluate the degradation of sulfur in two biological treatment plants in Tunisia: conventional plant of Rades Malienne, and vertical and horizontal flow from the Grombalia plant. We analyzed (1) wastewater properties, (2) the hydrosulfur (thiol) group, (3) membrane processes ultrafiltration technique and (4) characterization of the quality of wastewater from different plants. We used ultrafiltration membrane assisted ZnO and TiO2 NPs application on real effluents from different biological treatment plants. STEP1 is found to be more loaded with sulphur. Application of AC-ZnO membrane gives 99.07% and 99.55% of sulfur removal from wastewater of STEP1 and STEP3. STEP3 is 50 times less charged on sulfur than STEP1. We suggested that when the sulphur content is high, this leads to an increase in mineral elements. This could be explained by the interactions between thiols and the major elements that cause mineral pollution.


Author(s):  
Paula M. Crnkovic ◽  
Ivonete A´vila ◽  
Fernando E. Milioli ◽  
Josmar D. Pagliuso

Sulfur oxides are present in the gases from burning coals and these pollutants are harmful to the environment. Sulfur removal in the fluidized bed reactor applying limestones is an efficient technology. During sulfation, the formation of CaSO4 leads to the partial or complete blockade of the particle interior, resulting in a low efficiency of the use of limestones. As the desulphurization capacities of the sorbents are strongly affected by thermal condition, this paper focuses on the study of the development of the particles’ physical structure before and during sulfation reaction. The experiments were performed for two Brazilian limestones, a calcite and a dolomite. The particles were well characterized by BET analysis and mercury porosimetry and the behavior of the sorbents was observed through thermogravimetry analysis (TGA). The morphological analysis of the surface of both raw calcite and dolomite particles indicated that dolomite was a less compact sorbent. However, after calcination and sulfation, the change in pore and voids distributions showed that for dolomite both swelling and partial pore filling could take place, whereas for calcite the spaces between particles were maintained constant, possibly owing to a less intense swelling. In 30 min of reaction under air atmosphere TGA measurements provided conversions of 0.40 ±0.061 for the calcite, and 0.55 ±0.089 for the dolomite. The results showed strong dependence on meso and macropores region with high conversion of the sorbents. The reactivity differences between calcite and dolomite can also be explained based on the swelling of the particles.


Sign in / Sign up

Export Citation Format

Share Document