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Table 3.5.3 Summary of Mole Balances - Methanol-Synthesis Process

2 nd subscripts: CH 4 = 1, H 2O = 2, H 2 = 3, CO = 4, CO 2 = 5, N 2 = 6, CH 3OH = 7

MIXER (M-1)
Mole Balances

m
m
yi.i' i + X2,i 2 = Y3,i' m 3 (3.5.1)
yi, 3 'mi + Y2,3 m 2 = y 3, 3 m 3 (3.5.2)

yi/T m, + y 2, 4 m 2 = y 3j4 m 3 (3.5.3)
y\,s m, + y 2, 5 m 2 = y 3, 5 m 3 (3.5.4)

yi,6 f m, + y 2>6 m 2 = y 3>6' m 3 (3.5.5)
y2,i + y 2,3 + y 2,4 + yy + y 2,6 = 1 (3.5.6)

y 3/ + y 3,3 + y 3,4 + y^ + y^' = 1 (3.5.7)

Variables
y2,i - y 2,3 - y 2,4 - y2,s - y 2,e - ys,3 - y3,4 - y 3,s - m, - m 2 - m 3

Degrees of Freedom

F = l l - 7 = 4
CONVERTER (R-3)

(A) 2H 2 + CO -> CH 3OH

(B) 3H 2 + CO 2 -> CH 3OH + H 2O
Mole Balances

y 3/ m 3 = y 4jl m, (3.5.8)

x By3,5 m 3 = y 4)2m 4 (3.5.9)
y 3, 3 m 3 = y 4i3 rru + 2 X A y 3, 4 m 3 + 3 X B y 3>5 m 3 (3.5.10)

y 4, 4 m4 + x A y 3,4m 3 (3.5.11)
(3.5.12)
= y 4, 5 m, + X B y 3>5m 3

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