Document 896D5kvyENEMZVkG8Qwew7jm

668 CHAPTER 38 1946 Guide sensible heat removal simultaneously. In many industrial applications it is not necessary to aftercool the air. In applications requiring low drybulb temperatures excess sensible heat must be removed by an aftercooler. Since the absorption process can continue only as long as there is a difference in vapor pressure between the absorbent and the air-vapor mixture and since at a given temperature of the absorbent the vapor pressure depends on the concentration of the solution, evidently there must be a relation between these quantities which, if known, would state Fig. 3. Temperature--Pressure--Concentrations For Calcium Chloride the limits of the process. The relationship would also depend on the absorbent being used, and would have to be determined for each sub stance used as an absorbent. This relationship is shown graphically in Fig. 2 for lithium chloride, and Fig. 3 presents similar data for calcium chloride. These charts are essentially similar to Fig. 1, and their direct usefulness is limited by much the same considerations. Other physical .'properties of lithium chloride are shown in Tables 1, 2 and 3. In Fig. 2 and Table 1 the unit of concentration is the mol. An M molal solution is defined as a solution containing M X 42.37 grains of anhydrous ' lithium chloride.per 1000 grains of water. The formula connecting con-, centration in mols with weight in per cent is equivalent to:' (100 X MX 42.37) -f [1000 + (AfX 42.37)]. ' Dehumidification by Sorbent Materials 669 Table 1. Properties of Lithium Chloride Solutions Concen tration Pound Mols (42.4 Lb) UCl PER 1000 Lb Water Concen tration Per Cent by Weight Specific Gravity at 100 F Viscosity ' (Millipoise) 80 F 180 F Partial Heat of Mixing At 0 F. Btu per Lb Temp. Coeff. OF Partial Heat of Mixing Btu per Lb per F Specific Heat at 70 F Boiling Point F at (760 mm Hg) Freezing Point. F 10 no 7,8 14 ft 90 9 9ft.3 29.7 1.000 1.037 1.076 1.111 1.143 1.172 8.61 11.19 14.42 18.62 24.32 32.28 -3.48 4.56 601 7.78 10.00 12.91 0.00 2.04 7.24 16.70 31.90 51.10 0.000 -0.014 -0.036 -0.069 -0.109 -0.143 0.998 0.901 0.831 0.778 0.739 0;710 212.0 215.8 221.5 228.9 238.1 248.4 32.0 16.3 " 6.S --ii4,2 --69.0 --90.0 18 20 33 7 37 4 40 4 43.3 46.0 1.199 1.225 1.248 1.270 1.291 43.45 60.26 82.04 113.80 16.56 21.28 27.10 35.48 46.45 75.70 -0.160 90.80 -0.167 124.80 -0.176 145.00 -0,186 162.00 -0.194 0.687 0.666 0.647 0.631 258.8 268.9 277.9 285.8 293.2 -40.0 1.0 36.5 58.1 86.4 48 4 fiO 3 32 57.5 60.67 84.33 171.00 177.00 182.00 191.00 194.00 198.00 -0.200 -0.200 -0.210 -0.210 -0.210 -0.220 300.2 307.0 313.0 318.0 323.0 328.0 133.0 156.0 180.0 190.0 195.0 280.0 Table 2. Dew-Point of Air in Equilibrium with Lithium Chloride Solutions DewPoint at Zero Conc. 2.0 1 4.0 6.0 8.0 Concentration ot Lithium Chumuds 10.0 12.0 14.0 16.0 18.0 20.0 22.0 24.0 26.0 28.0 30.0 320 315.2 308.7 299.9 300 295.4 289.1 280.5 280 275.6 269.5 261.1 260 255.8 250.0 241.9 240 236.0 230.4 222.5 220 216.2 210.8 203.2 200 196.4 191.2 183.9 180 176.6 171.6 164.7 160 156.8 152.1 145.4 140 137.0 132.6 126.1 120 117.2 113.0 106:8 110 107.3 103.2 97.2 100 97.4 93.4 87.5 90 87.5 83.6 77.9 80 77.6 73.8 68.4 70 67.7 64.0 58.7 290.2 270.9 251.7 232.6 213:5 194.4 175.4 156.4 137.4 118.4 99.4 89.9 80.5 71.0 61.6 52.2 279.7 260.6 241.5 222.7 203.8 184.9 166.1 147.3 128.6 109.9 91.1 81.9 72.7 63.3 54.0 44.8 269.4 250.5 231.6 212.8 194.2 175.5 259.6 251.5 244.1 236.5 230.0 223.8 218.6 214.5 2103 240.8 -222.2 232.6 214.0 225.4 206.7 218.0 199.7 211.8 193.5 205.8 187.8 200.8 183.2 196.9 179.3 192.8 175.2 . 203.5 195.5 188.4 181.7 175.4 170.0 165.6 162.0 158.4 185.0 166.4 177.1 158.6 170.0 151.6 163.6 145.3 157.5 139.6 152.2 134.6 148.3 130.7 144.6 127-3 140.5 124.2. 156.7 148.0 140.3 133.5 127.3 121.9 117.0 113.3 110.1 138.1 129.6 1223 115.5 109.4 104.2 99.6 96.0 119.7 11U 103.9 97.4 91.6 86.6 82.2 101.3 93.1 85.9 79.5 73.8 69.0 82.7 74.7 67.8 61.5 56.0 73.5 65.6 58.8 52.6 47.1 64.4 56.6 49.8 43.7 38.2 55.2 47:6 40.8 34.8 29.3 46.1 38.5 31.8 25.9 20.6 37.0 29.5 22.9 17.2 12.0 60 57.8 54.3 49.1 42.7 35.5 27.9 20.5 14.0 ' 8-3 40 38.0 34.7 29.9 23.9 16.9 9.6 2.4 -3.9 .20 15.1 10.7 5.0 -1.7 . -8.7 -15.4 C --4.5 -8.6 -13.9 -20.2 `--27.0 -33.3 1'