So 27 n 12 H2O 18657 799947 0496 1323 n 12 n G1F n G1 N2 n G1 H2 n G1 H2O 00874

So 27 n 12 h2o 18657 799947 0496 1323 n 12 n g1f n g1

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So, ( )
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27 n 12, H2O = (18.657 + 7.99947) * 0.496 = 13.23 n 12 = n G1,F + n G1, N2 + n G1, H2 + n G1, H2O = 0.0874 + 14.796 + 0.874 + 13.23 = 28.988 n L1, H2O = n 10 + n 9, water (second run) n 12, H2O = 18.675 + 7.99978 13.23 = 13.445 n L1, M = 0 + n 11, M n 12, M = 0 + nGo 0 = 1.26 n 13 = n L1, M + n L1, F + n L1, H2O = 1.26 + 8.6526 + 13.445 = 23.358 1.2.5. Mass balance around the distillation column: Assumptions: 5- Light Key : methanol 6- Heavy key: H 2 0 7- Non-heavy key: formaldehyde 8- Constant Molal Overflow (CMO) n 14 = D + B ……………………………………………. (1) Dx M = frac. 1 * n 14 * x M,n14 = 0.997 * 23.458 * 0.054 = 1.25755 Bx M = (1 frac. 1 ) * n 14 * x M,n14 = 0.003784 Bx H2O = frac. 2 * n 14 * x water,n14 = 0.99 * 23.358 * 0.576 = 13.3197 Dx H2O = (1 frac. 2 ) * n 14 * x water,n14 = (1 -0.99) * 23.358 * 0.576 = 0.13454
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28 Bx F = 0.37 * 23.358= 8.6425 D = ΣDx Di = 1.25755 + 0.13454 = 1.39209 B = ΣBx Bi = 0.0038 + 13.3197 + 8.6425 = 21.966 x M, D = 0.9335 x H2O, D = 0.0.0966 x M, B = 0.00173 x F, B = 0.39345 x H2O, B = 0.60637 Component Mol fraction (yi) n j = y i * n tot Molecular weight m i = n i * M Mass faction x i = m i /M tot Methanol 0.00173 0.0038 32.042 0.12176 0.006244 Formaldehyde 0.39345 8.6425 30.026 259.5 0.51965 Water 0.60637 13.3194 18 239.73 0.4801 1.2.6. Mass balance around mixing point at streams 17, 18 and 19: Scaling up of the mass balance is needed in order to get the required production of 60000 ton/year of formaldehyde. Scaling up calculations was done and it is shown in the following finalized mass balance data sheets:
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29 1.3 Mass Balance Data Sheet 1- Initial mass balance (before Scaling) on 10 kmol methanol/hr. basis: 2- Initial mass balance (before Scaling) on kilogram/year mass unit: stream number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 methanol 0 8.7466 10 10 0 10 0 10 1.26 1.26 0 0 1.26 1.26 1.25755 0.0038 0.0038 0 0.0038 0.0038 oxygen 3.933 0 0 0 3.933 0 3.933 3.933 0 0 0 0 0 0 0 0 0 0 0 0 formaldehyde 0 0 0 0 0 0 0 0 8.74 8.74 0 0.0874 8.6526 8.6526 0 8.6425 8.6425 0 8.6425 8.6425 water 0 0 0.13378 0.13378 0 0.13378 0 0.13378 7.99978 7.99978 18.675 13.23 13.445 13.445 0.13454 13.3197 13.3197 11.16667 24.48637 24.48637 hydrogen 0 0 0 0 0 0 0 0 0.874 0.874 0 0.874 0 0 0 0 0 0 0 0 nitrogen 14.796 0 0 0 14.796 0 14.796 14.796 14.796 14.796 0 14.796 0 0 0 0 0 0 0 0 summation kmol/hr 18.729 8.7466 10.13378 10.13378 18.729 10.13378 18.729 28.86278 33.66978 33.66978 18.675 28.9874 23.3576 23.3576 1.39209 21.966 21.966 11.16667 33.13267 33.13267 stream number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 methanol 0 280.2586 320.42 320.42 0 320.42 0 320.42 40.37292 40.37292 0 0 40.37292 40.37292 40.29442 0.12176 0.12176 0 0.12176 0.12176 oxygen 125.856 0 0 0 125.856 0 125.856 125.856 0 0 0 0 0 0 0 0 0 0 0 0 formaldehyde 0 0 0 0 0 0 0 0 262.4272 262.4272 0 2.624272 259.803 259.803 0 259.4997 259.4997 0 259.4997 259.4997 water 0 0 2.40804 2.40804 0 2.40804 0 2.40804 143.996 143.996 336.15 238.14 242.01 242.01 2.42172 239.7546 239.7546 201 440.7546 440.7546 hydrogen 0 0 0 0 0 0 0 0 1.748 1.748 0 1.748 0 0 0 0 0 0 0 0 nitrogen 414.288 0 0 0 414.288 0 414.288 414.288 414.288 414.288 0 414.288 0 0 0 0 0 0 0 0 summation kg/hr 540.144 280.2586 322.828 322.828 540.144 322.828 540.144 862.972 862.8322 862.8322 336.15 656.8003 542.1859 542.1859 42.71614 499.3761 499.3761 201 700.3761 700.3761
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30 3- Mass balance (after Scaling) on ton/year mass unit: 4- Mass balance (after Scaling) on kmol/year mass unit: stream number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 methanol 0 24009.26 27449.82 27449.82 0 27449.82 0 27449.82 3458.678 3458.678 0 0 3458.678 3458.678 3451.953 10.43093 10.43093 0 10.43093 10.43093 oxygen 10781.865 0 0 0 10781.86 0 10781.86 10781.86 0 0 0 0 0 0 0 0 0 0 0 0 formaldehyde 0 0 0 0 0 0 0 0 22481.69 22481.69 0 224.8169 22256.87 22256.87 0 22230.89 22230.89 0 22230.89 22230.89 water 0 0 206.2926 206.2926 0 206.2926 0 206.2926 12335.89 12335.89 28797.39 20401.04 20732.58 20732.58