Acid Dew Point Calculation Spreadsheet [PDF]

Zitiervorschau

244606215.xls.ms_office

Calculations for Recommended Flue Gas temperature to avoid S-dew point corrosion. INPUTS SO2 in flue gas ppm v/v 220 FD Fan outlet air temperture 150 Flue gas pressure-Air preheater outlet 5100 H2O in flue gas 11.92

ppm v/v deg.c. mm WC % vol

as given by EMS Lab/Online analyser Site Reading Site Reading Lab analysis

CALCULATION(Please do not change the formulae) SO2 in flue gas vol % 0.022 H2O in flue gas vol % 5 5100 mm WC Flue gas pressure 200.79 inch WG 1.4933 ata

Dew Point of Acid Vapors Sulfurous acid 1000/Tdp=2.276-0.0294 ln(PH2O)-.0858 ln(PSO3)+0.0062 ln(PH2O)ln(PSO3) The dew points are in deg K and partial pressures in mm Hg.

PH20 84.742 mm Hg Ln(PH2O) 4.4396 SO2 to SO3 2% wt. basis PSO3 0.004 mm Hg Ln(PSO3) -5.523 1000/Tdp

tw=tg-(tg-ti)xhi/(hi+ho) tw=average tube wall temperature tg,ti= flue gas and air inlet temperatures hi,ho= tube side and gas side heat transfer coefficients In an air preheater ,hi and ho=10 & 15 Btu/ft2hF

Tdp

2.467309 405.2999 deg K 132.2999 Deg C

tw recomm.

132.2999

hi/(hi+ho) =

0.4

tI = tw= tg =

150 132.2999 120.4999

RESULTS S-Dew Point Temperature Recommended Flue gas Temp

132.3 Deg.c. 120.5 Deg.c. Issued by

Technical Services TCL Mithapur PAGE 1

244606215.xls.ms_office

18/04/2003

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