Arsenic and selenium distribution and speciation in coal and coal combustion by-products from coal-fired power plants

Xie, Jin; Niu, Xiao-Dong; He, Kai-Qiang; Shi, Meng-Dan; Yu, Sujuan; Yuan, Chun-Gang; Liu, Jingfu

doi:10.1016/j.fuel.2021.120228

Cited by 35 publications

(11 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The SD and relative standard deviation (RSD) of each group, which reflected the degree of dispersion and accuracy of data, were also calculated. The results showed that the SD of each experiment was less than 5, and thr RSD was less than 20%, [ 30 ] which evidences the repeatability and accuracy of the experiment.…”

Section: Methodsmentioning

confidence: 99%

Migration and emissions of selenium during chemical looping combustion of coal

Kang

Guo

et al. 2022

Can J Chem Eng

View full text Add to dashboard Cite

Selenium is one of the most volatile toxic elements in coal, and its emissions must be strictly controlled. Chemical looping combustion (CLC) is a clean and efficient technology for coal. Herein, the iron-based oxygen carrier (OC) was used as an adsorbent to study the migration and emissions of selenium during the CLC of coal. Due to the oxidation and adsorption of selenium by ironbased OC, most of the selenium was retained in OC or distributed in the CO 2 stream. The proportion of gaseous selenium released into the atmosphere was less than 10%-significantly lower than that from the traditional combustion process of coal, which had a value of 91.79%. The presence of OC increased the distribution phase of selenium, promoted the conversion of gaseous selenium to solid selenium, and reduced selenium emissions in flue gas. During CLC of coal, the fuel reactor (FR) temperature and the number of OC re-oxidation cycles played an important role in the emissions and retention of selenium.The increasing FR temperature increased the gaseous selenium in the CO 2 stream, reduced the particulate selenium absorbed by OC, and reduced the selenium emissions in the atmosphere. After 10 continuous CLC cycles, the selenium concentration in OC increased from 0.889 to 8.20 mg kg À1 . The continuous cycling of CLC could realize the enrichment of selenium from coal to OC. Furthermore, the migration and transformation mechanism of selenium during CLC was deduced by experiments and thermodynamic simulation. This research provides a suitable reference for reducing selenium emissions and developing CLC technology. K E Y W O R D S chemical looping combustion, coal, iron-based oxygen carrier, selenium | INTRODUCTIONCoal is an important basic energy source that promotes rapid economic development and is a major source of carbon dioxide (CO 2 ) emissions. To reduce the impact of CO 2 emissions on global climate change, it is urgent to develop efficient and low-cost CO 2 capture technologies. [1] Chemical

show abstract

Section: Methodsmentioning

confidence: 99%

Migration and emissions of selenium during chemical looping combustion of coal

Kang

Guo

et al. 2022

Can J Chem Eng

View full text Add to dashboard Cite

show abstract

“…The next contribution in this section, from Xie et al , 81 described a method for As and Se distribution and speciation in coal and combustion by-products from coal fired power plants . In this study, a mixture of 1 M H 3 PO 4 and 0.1 M ascorbic acid was used to release As from coal and related solid wastes.…”

Section: Organic Chemicals and Materialsmentioning

confidence: 99%

Atomic spectrometry update: review of advances in the analysis of metals, chemicals and materials

Carter

Clough

Fisher

et al. 2021

J. Anal. At. Spectrom.

View full text Add to dashboard Cite

show abstract

“…Studies indicate that SeO 3 2– is more likely to migrate into the solid phases compared with SeO 4 2– . SeO 3 2– is also determined as the main selenium component in gypsum . Our previous work further investigated the process of selenium migration into gypsum .…”

Section: Introductionmentioning

confidence: 96%

“…33 SeO 3 2− is also determined as the main selenium component in gypsum. 34 Our previous work further investigated the process of selenium migration into gypsum. 35 The investigation suggests that only SeO 3 2− could migrate into gypsum during the crystal growth process of gypsum because SeO 4 2− could not stably exist in the gypsum crystal structure.…”

Section: Introductionmentioning

confidence: 99%

Comprehensive Effect of Oxidant Addition in an FGD Slurry on the Removal and Distribution of Selenium: A Field Study

Weng

Tian

Wang³

et al. 2022

Environ. Sci. Technol.

View full text Add to dashboard Cite

Flue gas desulfurization (FGD) scrubbers capture selenium in coal-fired power plants, leading to a high concentration of selenium in the slurry. This research proves that SO 3 2− is preferentially oxidized compared to SeO 3 2− by S 2 O 8 2− . With the increase in the oxidation−reduction potential (ORP) caused by S 2 O 8 2− addition, the conversion rate of SO 3 2− increased and the size of gypsum grains grew from 31.2 to 34.6 μm. SeO 3 2− migrates into gypsum grains during the growth of CaSO 4 •2H 2 O, leading to selenium fixation in gypsum.In a field study of a 350 MW unit, the ORP increased from 142 to 450 mV when Na 2 S 2 O 8 was fed into the FGD slurry. With the addition of the oxidant, 65.1% of selenium in the liquid phase migrated into gypsum. The concentration of selenium in the leachate of gypsum after oxidant addition decreased by 68.0%. A 2.34% increase in the selenium removal rate was observed in the scrubber. This study focuses on the migration and conversion of selenium in an actual FGD slurry via a field test. The results found in the 350 MW unit are consistent with laboratory results. The change in ORP has been proven to be effective in adjusting the selenium distribution in the FGD slurry.

show abstract

Arsenic and selenium distribution and speciation in coal and coal combustion by-products from coal-fired power plants

Cited by 35 publications

References 38 publications

Migration and emissions of selenium during chemical looping combustion of coal

Migration and emissions of selenium during chemical looping combustion of coal

Atomic spectrometry update: review of advances in the analysis of metals, chemicals and materials

Comprehensive Effect of Oxidant Addition in an FGD Slurry on the Removal and Distribution of Selenium: A Field Study

Contact Info

Product

Resources

About