In Example 17-14, part \(\mathrm{A}, \Delta \mathrm{L}_{\text {growth }}=0.2971 \mathrm{~mm}\) compared to \(0.2918 \mathrm{~mm}\) in Example 1713. Why does the very sharp seed distribution \(\left(\mathrm{L}_{\mathrm{S}}=0.15 \mathrm{~mm}\right.\) for all particles) show more growth than the slightly wider distribution \(\left(\mathrm{L}_{\mathrm{S}}=0.13,0.15\right.\) and \(\left.0.17 \mathrm{~mm}\right)\) despite the same median particle size?

Example 17-13

Example 17-14

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A saturated aqueous solution of sodium acetate NaC2H3O2 at 40C is cooled to 0C and fed to a continuous crystallizer. For each 100 kg of entering water, 2.5 kg of hydrated seed crystals are added. The seeds are very tightly classified and can be considered to consist of three sizes, 30% by weight 0.13 mm, 40% by weight 0.15 mm, and 30% by weight 0.17 mm. Data: From Table 17-1, the stable form of sodium acetate crystals at 0C is hydrate NaC2H3O2-3H2O, and solubilities are (in g anhydrous NaC2H3O2 per 100 g water) 65.5 at 40C, 36.3 at 0C. Phydrate = 1450 kg/m, k = 1.0. A. Find kg/h of hydrate and anhydrous products per 100 kg/h of water feed. B. Find the weighted average size of product. C. If t = 19 h, find the linear growth rate required. TABLE 17-1. Solubilities of selected inorganic and organic compounds in water Compound Formula Stable Hydrate T, C, Solubility, kg Anhydrous Compound/100 kg Water # HO 0 20 40 60 80 100 Ammonium NH4Br 60.6 75.5 91.2 108 126 146 bromide Ammonium NH4CI 29.4 37.2 45.8 55.3 65.6 77.3 chloride Ammonium NH4 155 172 iodide Ammonium NH4NO 118.3 192 nitrate Ammonium (NH4)2SO4 209 229 250 421 580 871 70.6 75.4 88 95 103 sulfate Barium chloride BaCl2 Calcium chloride CaCl2 Cobalt chloride CoCl2 Copper sulfate CuSO4 Lithium chloride LiCI Magnesium Mch chloride Manganese MnCl chloride Nickel chloride NiCl2 Potassium chloride KCI 2 6 56 61 31.2 35.8 40.8 46.2 52.5 59.4 59.5 74.5 128 137 147 159 43.5 52.9 69.5 93.8 97.6 106 14.3 20.7 28.5 40.0 55.0 75.4 69.2 83.5 89.8 98.4 112 128 52.9 54.6 57.5 61.0 66.1 73.3 63.4 73.9 88.5 109 113 115 53.4 60.8 73.2 81.2 86.6 87.6 28.0 34.2 40.1 45.8 51.3 56.3 Potassium KF FFF 44.7 94.9 138 142 150 | fluoride Potassium nitrate KNO3 13.3 31.6 63.9 110 169 247 Sodium acetate NaC2H3O2 139 153 170 Sodium acetate NaCH3O2 3 36.3 46.5 65.5 139 Sodium chloride NaCl 35.7 36.0 36.6 37.1 38.0 39.2 Sodium nitrate NaNO3 73 88 104 124 148 180 Sodium sulfate Na2SO4 48.8 45.3 43.7 42.5 Sodium sulfate NaSO4 7 19.5 44.1 Sodium sulfate Na2SO4 10 5.0 19.4 Benzoic acid C6H3COOH 0.17 0.29 0.56 1.16 2.72 Citric acid C3H4OH(COOH)3 1 96 Fructose C6H12O6 75 Glucose CH12O6 46 8 146 215 277 372 80 85 90 - 92 160 280 440 - Sucrose C12H22O11 179 204 238 287 362 | | 8 5.88 526 487