Numerical analysis of the operating characteristics of a large‐scale <scp>CFB</scp> coal‐gasification reactor with the <scp>QC‐EMMS</scp> drag model

Liu, Yang; Huo, Pengju; Li, Xiaohong; Qi, Haiying

doi:10.1002/cjce.23911

Cited by 2 publications

(1 citation statement)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Due to the variety of configurations and their multiple effects on the solid-gas two-phase flow, there has been minimal research on the intake and outlet effects on the hydrodynamics in risers or combustors, but no precise classification or understanding has been reached. Therefore, it is crucial to comprehend the riser inlet sections' hydrodynamic properties [15]. It has been demonstrated that a CFB's riser output geometry significantly affects the hydrodynamics of the component.…”

Section: Introductionmentioning

confidence: 99%

Emissions Reduction by Combustion Modeling in the Riser of Fluidized Bed Combustor for Thar Coal Pakistan

Butt

Nergis

Ahmad

et al. 2022

PPASB

View full text Add to dashboard Cite

Pakistan has experienced a protracted electricity shortage for the past few years. However, despite Pakistan’s abundant coal deposits, modern coal combustion technology is still required to reduce emissions. Pakistan is struggling to utilize its energy resources and currently experiencing an electrical shortage of more than 8000 MW. The research study models the combustion performance in a fluidized bed riser using ANSYS FLUENT software to understand the combustion behavior of low-rank Thar coal. A simple circulating fluidized bed (CFB) combustion riser was modeled for computational fluid dynamics (CFD) to study the hydrodynamics of gas-solid flow in a circulating fluidized bed riser to reduce emissions and operating costs. Three different types of risers/combustors geometries were used center flow, counter flow, and parallel flow. The CFD model for the solids segment with a k-e turbulence model and the viscosity of static particles in the gas segment both showed excellent mixing performance. According to the FLUENT data, the riser/combustor maximum temperature is around 1400 K or 1130 o C at the primary burning sector in the bed center. According to velocity contours, the greatest velocity in the center-oriented riser/combustor peaks at 3.3 m/s. The CO and CO2 both mass fraction counters show maximum concentration in the center geometry, whereas lower CO concentration is found in parallel geometry. The lowest level of NOx is established in the parallel geometry at around 15 ppm, whereas the counter contours establish the maximum level of NOx at about 31 ppm. Circulating Fluidized Bed Combustor is found to be the most advantageous and effective technology for producing power from Thar lignite coal and reducing emissions.

show abstract

Section: Introductionmentioning

confidence: 99%

Emissions Reduction by Combustion Modeling in the Riser of Fluidized Bed Combustor for Thar Coal Pakistan

Butt

Nergis

Ahmad

et al. 2022

PPASB

View full text Add to dashboard Cite

show abstract

Investigation on influences of loose gas on gas-solid flows in a circulating fluidized bed (CFB) reactor using full-loop numerical simulation

Huo

Liu

et al. 2020

International Journal of Chemical Reactor Engineering

View full text Add to dashboard Cite

The influences of loose gas on gas-solid flows in a large-scale circulating fluidized bed (CFB) gasification reactor were investigated using full-loop numerical simulation. The two-fluid model was coupled with the QC-energy minimization in multi-scale theory (EMMS) gas-solid drag model to simulate the fluidization in the CFB reactor. Effects of the loose gas flow rate, Q, on the solid mass circulation rate and the cyclone separation efficiency were analyzed. The study found different effects depending on Q: First, the particles in the loop seal and the standpipe tended to become more densely packed with decreasing loose gas flow rate, leading to the reduction in the overall circulation rate. The minimum Q that can affect the solid mass circulation rate is about 2.5% of the fluidized gas flow rate. Second, the sealing gas capability of the particles is enhanced as the loose gas flow rate decreases, which reduces the gas leakage into the cyclones and improves their separation efficiency. The best loose gas flow rates are equal to 2.5% of the fluidized gas flow rate at the various supply positions. In addition, the cyclone separation efficiency is correlated with the gas leakage to predict the separation efficiency during industrial operation.

show abstract

Numerical analysis of the operating characteristics of a large‐scale CFB coal‐gasification reactor with the QC‐EMMS drag model

Cited by 2 publications

References 45 publications

Emissions Reduction by Combustion Modeling in the Riser of Fluidized Bed Combustor for Thar Coal Pakistan

Emissions Reduction by Combustion Modeling in the Riser of Fluidized Bed Combustor for Thar Coal Pakistan

Investigation on influences of loose gas on gas-solid flows in a circulating fluidized bed (CFB) reactor using full-loop numerical simulation

Contact Info

Product

Resources

About