Simulation of Coal Gasification in a Low-Temperature, High-Pressure Entrained-Bed Reactor with a Volatiles Condensation and Re-Evaporation Model

Abstract

The objective of this study is to implement a tar condensation and re-vaporization sub-model in a previously established Computational Fluid Dynamics (CFD) model for the Entrained Slagging Transport Reactor (E-STR) gasifier, modified from the existing E-Gasifier simulation models in previous studies. The major modifications in E-STR, compared to the existing E-GasTM design, include higher operating pressure and lower temperature, with the aim of achieving a higher H2/CO ratio of syngas, which is more favorable for synthetic natural gas (SNG) production. In this study, the aforementioned sub-model is described by the UDF (User-Defined Function) and incorporated in a previously developed computational model for entrained-flow gasification process, to study the syngas composition without implementing a tars-cracking catalyst in the E-STR gasifier. The results show that incorporating the tar condensation model leads to a formation of approximately 6.47% liquid volatiles and an exit temperature increase about 135 K, due to the release of latent heat. These sub-models have been successfully implemented and will be useful in the condition that the gasifier temperature is intentionally kept low, just as the E-STR gasifier. The results indicate that high pressure and less oxygen feed produce a higher H2/CO ratio, more favorable for SNG production.

RETRACTED ARTICLE: Coastline geological parameters and beach motion image simulation based on particle swarm optimization

“…Nowadays, many studies on the pore structure of shale are limited to specific shale blocks, and do not comprehensively summarize the commonalities of shale storage layers, but only analyze the characteristics of specific shale storage layers. Therefore, the research on the relationship between the pore size distribution of marine and terrestrial shale and geological parameters is not very extensive (Chen et al 2019).…”

Unraveling the Relationship between Zeolite Structure and MTO Product Distribution by Theoretical Study of the Reaction Mechanism

“…The conversion of methanol to olefins (MTO) over acidic zeolites is an effective alternative way to cracking of naphtha to light olefins, as methanol can be expediently produced via synthesis gas from multifarious carbon sources such as coal, natural gas, and biomass. − In the past decades, a great deal of effort has been devoted to the elucidation of MTO mechanisms on the basis of experimental and theoretical studies. − A consensus has been reached that the hydrocarbon pool (HCP) mechanism, including aromatic-based and alkene-based cycles, dominates the reaction process at the steady period. In the aromatic-based cycle, polymethylbenzenes (polyMBs) trapped in zeolite pores are considered as active HCP species, whereas the alkene-based cycle is based on the successive methylation and cracking reactions of C 3 + alkenes .…”

Allothermal Gasification of Peat and Lignite by a Focused Light Flow

“…Therefore, it is a relevant task currently to develop efficient and inexpensive methods of converting fossil fuels into synthesis gas. The most well-known gasification techniques suggest the conversion of fuel through its partial combustion [11][12][13]. This method is good, but it requires special efforts to keep the efficiency at a high enough level when the fuel has low reactivity and high ash content [14,15].…”

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