Answer Happy

A reverse osmosis membrane to be used at 25°C for NaCl feed solution (density 999 kg/m3) containing 2.5 g NaCI/L has a water permeability constant A-4.81*10* kg/s/m²/atm and a solute NaCl permeability constant A.-4.42 107 m/s. Assume the permeate contains 0.1 kg NaCl/m³. The pressure drop across membrane is 27.2 atm. You can take a basis of 1 m³ solution. 1) Calculate osmotic pressure of feed solution [2 marks] 2) Calculate osmotic pressure of permeate. [1 mark] 3) Calculate water and solute flux through membrane. [2 marks] 4) Calculate solute rejection. [2 marks] 5) As a chemical engineer, you were asked to investigate increasing water flux across membrane. What are your suggestions? [1 Mark] 6) Explain two reasons for RO becoming the favorite technology in Bahrain? [2 marks] TABLE 1 Osmotic Pressure of Various Aqueous Solutions at 25°C Sodium Chloride Solutions Sea Salt Solutions Sucrese Solutions gmol NaCl Density W+% Selts (kg/m³) kg H₂O 10 997.0 997 4 10011 1017 2 1036 2 1072 3 0.01 0.10 0.50 100 2.00 Aw B = As Cwz NA (AP-Art) Osmetic pressure (atm) 10 0 100 0.47 4.56 1.45 7.50 45.80 10:00 96-20 R=C1-C₂= B(AP-6M) 1+B(AP-AM) Oumatic Pressure (atm) 0 7:10 25.02 58.43 82.32 Salute Mel. Fr. X10¹ 0 1798 5.375 1049 17.70 Oumatic pressurs 。 2.48 7.48 15.31 26.33