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Journal of Mechanical Science and Technology

, Volume 33, Issue 11, pp 5499–5505 | Cite as

Experimental and numerical study of coal swirl fluidized bed drying on 100 angle of guide vane

  • Melvin Emil SimanjuntakEmail author
  • Prabowo
  • Wawan Aries Widodo
  • Sutrisno
  • M. B. H. Sitorus
Article
  • 9 Downloads

Abstract

Currently, low-rank coal is widely used as fuel in power plants. The swirl flow method is quite effective used to increase heating value through the drying process. This research studies the characteristics of low-rank coal drying using a swirl fluidized method with 100 angle of blade inclination experimentally and numerically. Coal with a moisture content of 25.17 % and a size of 6 mm was dried by dry air with a temperature of 55 °C, the relative humidity of 10.5 % and flow rate of 0.06 kg/sec. Moisture content is measured by the ASTM D3173. Numerical simulations performed in 3 dimensional, transient and multicomponent. The results of the experiment show that drying was effective in the first 5 minutes, which reduced moisture ratio to 0.26 while the simulation results reduced moisture ratio to 0.28. Numerical simulations show the pathline, velocity vectors, temperature, and humidity contours. Particle trajectory as simulation results agrees to the experiment.

Keywords

Coal Swirl fluidized bed Drying Angle of blade inclination Experimental Numerical 

Nomenclature

MR

Moisture ratio

Mi

Moisture content at initial time

Me

Moisture content at equilibrium

M

Moisture content at time, t

mvap

Mass of moisture evaporated, kg

hfg

Enthalpy evaporation, J/kg

mair

Mass of moisture evaporated, kg

Δhair

Increasing of air dryer enthalpy, J/kg

mp

Particle mass, kg

Cp

Heat specific of coal particle, J/kgK

Tp

Particle temperatur, K

h

Coefficient of convection, W/m2K

Ap

Surface area of particle, m2

T

Infinity temperature, K

dmp

Reducing of particle mass, kg

Ni

Molar flux of vapor (kmol/m2-s)

kc

Mass transfer coefficient (m/s)

Ci, s

Vapor concentration at the droplet surface (kmol/m3)

Ci,∞

Vapor concentration at the droplet surface (kmol/m3)

FD

Drag force, kgm/s2

u⃗

Velocity vector of air dryer, m/s

u⃗p

Velocity vector of particle, m/s

ρp

Density of particle, kg/m3

ρ

Density of air dryer, kg/m3

Re

Reynolds number

dp

Particle diameter, m

CD

Drag coefficient

μ

Dynamic viscosity, kg/m.s

a1, a2, a3

Are constants that apply over several ranges of Re given by Morsi and Alexander

Psat

Saturation pressure, Pa

R

Universal gas constant, 8134 J/mol K

εD

Drying efficiency

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Notes

Acknowledgments

The author acknowledges for the support funding for Sepuluh Nopember Institute Technology, Surabaya, and Medan State Polytechnic, Indonesia.

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Copyright information

© KSME & Springer 2019

Authors and Affiliations

  • Melvin Emil Simanjuntak
    • 1
    Email author
  • Prabowo
    • 2
  • Wawan Aries Widodo
    • 2
  • Sutrisno
    • 3
  • M. B. H. Sitorus
    • 1
  1. 1.Department of Mechanical EngineeringMedan State PolytechnicMedanIndonesia
  2. 2.Department of Mechanical EngineeringSepuluh Nopember Institute TechnologySurabayaIndonesia
  3. 3.Department of Mechanical EngineeringPetra Christian UniversitySurabayaIndonesia

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