The mobilisation of sodium and potassium during coal combustion and gasification

Thompson, D.; Argent, B.B.

doi:10.1016/s0016-2361(99)00115-5

Cited by 41 publications

(36 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Substantially less is known about the mechanistic and chemical aspects of deposit formation during gasification of coal and biomass mixtures, especially following the exposures to high temperatures and pressures characteristic of EF gasifiers. In contrast to combustion under oxidizing conditions, thermodynamic modeling predicts a much higher proportion of alkali in the gas phase under reducing conditions during gasification [9]. Alkali species in coal are mostly associated with mineral matter and are not easily volatilized during gasification.…”

Section: Scientific and Technical Meritmentioning

confidence: 99%

“…In the presence of chlorine, alkali chlorides become the most thermodynamically stable gas-phase alkali species at the high temperatures that are typical in EF gasifiers. Additionally, experiments and thermodynamic modeling show that under both combustion and gasification conditions the alkali volatilization can be significantly enhanced by chlorine [9,10]. For the biomass feedstocks of interest in this program, the concentrations of sulfur and nitrogen species in the product gas from biomass gasification are expected to be lower, compared to those from coal gasification.…”

Section: Scientific and Technical Meritmentioning

confidence: 99%

See 1 more Smart Citation

Product Characterization for Entrained Flow Coal/Biomass Co-Gasification

Shawn¹,

Subramanian²,

Rizeq³

et al. 2011

View full text Add to dashboard Cite

Section: Scientific and Technical Meritmentioning

confidence: 99%

Section: Scientific and Technical Meritmentioning

confidence: 99%

Product Characterization for Entrained Flow Coal/Biomass Co-Gasification

Shawn¹,

Subramanian²,

Rizeq³

et al. 2011

View full text Add to dashboard Cite

“…Thermodynamic calculations have shown the amount of alkali in the gas phase is proportional to the amount of chloride in the atmosphere. Alkali–halide salts, in the presence of sulfur and oxygen, speciate as Na 2 SO 4 , which presumably makes the alkali more reactive towards slag‐forming species.…”

Section: Introductionmentioning

confidence: 99%

Alkali, boron and phosphorous removal from coal‐derived syngas: review and thermodynamic considerations

Dolan

Ilyushechkin

McLennan

et al. 2011

Asia-Pacific J Chem Eng

View full text Add to dashboard Cite

Alkalis are highly corrosive towards materials associated with syngas processing and utilisation, including ceramic particulate filters and metallic components. The removal of alkali species, consequently, is an important step in the cleaning of coal and biomass-derived syngas. The origins of the alkali contaminant govern the ability of specific sorbents to remove these species via chemical means. Alkali salt removal is dependent on the formation of an acid halide species, a reaction, which in the absence of H 2 O, involves hydrogen and carbon dioxide. This reaction becomes increasingly unfavourable above 1000 C, but below this temperature, equilibrium conversion approaches 100%. The fluxing of a gasifier slag, which is often necessary to reduce viscosity to a level that allows tapping, reduces its ability to absorb alkali halides. This effect however was not observed with oxide-based alkalis, which shows strong affinity for gasifier slag regardless of fluxing, up to 1600 C. Furthermore, there is a potential for removal of boron and phosphorous contaminants using these same sorbents. In a complete high-temperature, dry gas cleaning sequence, alkali removal would ideally be undertaken prior (or simultaneously to) halide removal and prior to sulfur removal.

show abstract

“…However, our results based on field 445 measurements in Shanghai go against the inherent notion of Cu origins. Gathering evidences have shown that topsoil and coal ash are also enriched in K (Schlosser, et al, 2002;Thompson and Argent, 1999;Westberg et al, 2003;Reff et al, 2009 …”

mentioning

confidence: 99%

First long-term and near real-time measurement of atmospheric trace elements in Shanghai, China

Chang

Huang

Deng

et al. 2017

Preprint

View full text Add to dashboard Cite

Atmospheric trace elements, especially metal species, are an emerging environmental and health concern with poorly constrained on its abundances and sources in Shanghai, the most important industrial megacity in China. Here we 20 continuously performed a one-year (from March 2016 to February 2017) and hourlyresolved measurement of eighteen elements in fine particles (PM2.5) at Shanghai urban center with a Xact multi-metals monitor and several collocated instruments.Independent ICP-MS offline analysis of filter samples was used to validate the performance of Xact that was based on energy-dispersive X-ray fluorescence analysis Ni were confirmed as the prominent and exclusive tracer of heavy oil combustion from shipping traffic. Fe and Ba were strongly related to brake wear, and exhibited significant 45 correlation with Si and Ca, suggesting that Si and Ca in Shanghai were primarily sourced from road fugitive dust rather than long-distance dust transport and local building construction sites. Stationary combustion of coal was found to be the major source of As, Se, Pb, Cu and K, and the ratio of As/Se was used to infer that coal consumed in Shanghai likely originated from Henan coal fields in Northern China. Cr, 50Mn and Zn were the mixed result of emissions from stationary combustion coal, ferrous metals production, and nonferrous metals processing. Ag and Cd in Shanghai urban atmosphere were also the mixture of miscellaneous sources. Collectively, our findings in this study provide baseline data with high detail, which are needed for developing effective control strategies to reduce the high risk of acute exposure to atmospheric 55 trace elements in China's megacities.Atmos. Chem. Phys. Discuss., https://doi

show abstract

The mobilisation of sodium and potassium during coal combustion and gasification

Cited by 41 publications

References 9 publications

Product Characterization for Entrained Flow Coal/Biomass Co-Gasification

Product Characterization for Entrained Flow Coal/Biomass Co-Gasification

Alkali, boron and phosphorous removal from coal‐derived syngas: review and thermodynamic considerations

First long-term and near real-time measurement of atmospheric trace elements in Shanghai, China

Contact Info

Product

Resources

About