Investigation on detachable vertical tube evaporator for small scale multi effect distillation system: Design, modelling, fabrication and experimental analysis

• Published in: Heat and mass transfer 2022-08, Vol.58 (8), p.1441-1458
• Main Authors: Deharkar, Rahul, Mudgal, Anurag, Patel, Vivek
• Format: Article
• Language: English
• Subjects: Boiler tubes; Detaching; Distillation; Engineering; Engineering Thermodynamics; Evaporation; Evaporators; Experimentation; Fresh water; Heat and Mass Transfer; Heat transfer coefficients; Industrial Chemistry/Chemical Engineering; Inlet temperature; Maintenance; Original Article; Pilot plants; Salt deposits; Thermodynamics; Thin films; Water temperature
• ISSN: 0947-7411; 1432-1181
• DOI: 10.1007/s00231-022-03185-3

Design and experimental performance of a detachable shell vertical tube evaporator with variation in feed water temperature is performed. The modified evaporator operates with a thin film of evaporating feed water on the outer surface of fluted tubes, resulting in high heat transfer coefficient for performance. Also, salt deposits on the outer surface, make the system easy for cleaning and maintenance. A detachable outer shell further allows ease for tubes maintenance. Baby boiler and parabolic dish collector together producing 30 kg/hr steam were installed with the pilot plant for experimental study. Experimentation of the evaporator as single effect with condenser system recorded a mean heat transfer coefficient of 9446 W/m 2 K at gain output ratio of 1.8 ± 0.02 for feed inlet temperature, motive steam pressure and temperature in at 100 °C, 1.3 ± 0.028 bar and 103 ± 0.5 °C respectively. The pilot plant with a single effect produce a maximum of 1282 L/day at fresh water cost of 1.05 $/m 3 . Theoretical Model for multi effect system in parallel feed flow configuration estimates lowest freshwater cost of 0.73 $/m 3 and total production of 2668 L/day with 4 effect system. Graphical abstract