A solution of sodium hydroxide leaves a dissolver at 80ŽC and is to be cooledto 40ŽC, using cooling water. The maximum flow-rate of the solution will be8000 kg/h. The maximum inlet temperature of the cooling water will be 20ŽCand the temperature rise is limited to 20ŽC.Design a double-pipe exchanger for this duty, using standard carbon steel pipe andfittings. Use pipe of 50 mm inside diameter, 55 mm outside diameter for the innerpipe, and 75 mm inside diameter pipe for the outer. Make each section 5 m long.The physical properties of the caustic solution are:temperature, ŽC 40 80specific heat, kJkg1ŽC1 3.84 3.85density, kg/m3 992.2 971.8thermal conductivity, Wm1ŽC1 0.63 0.67viscosity, mN m2s 1.40 0.43