Performance and economic analysis of the distilled seawater desalination process using low-temperature waste hot water

Abstract In this paper two waste-heat-driven MED desalination processes (HW-MED and Boost-HW-MED) using waste hot water from petrochemical industry were developed. The thermodynamic model of the two MED systems was established based on the energy and mass balance equations. Taking the typical production capacity of 10,000 m 3 /d as example the gained output ratio and total heat transfer area were selected as property indexes to compare the systemic performance of the two desalination processes based on the model calculation data. The effect of inlet temperature, outlet temperature and flow rate on the system performance were emphatically studied. Results showed that every 1 °C increment in feed water temperature would increase the output of freshwater by approximately 438 m 3 /d, and every 1 °C increase in return water temperature would decrease the output by 417 m 3 /d. Finally as the first recommendation, the investment and water-making cost of HW-MED process was investigated and compared with the common TVC-MED system. The operating cost of HW-MED system is only 2.354 RMB/m 3 , which is 39.5% lower than that of TVC-MED system motived by commodity steam. The financial evaluation and sensitivity analysis on the cost was carried out. The results show that HW-MED process has a strong ability to resist fluctuations of the freshwater production price, raw material prices and the total investment. The conclusion provides data reference and theoretical support for desalinating seawater using waste heat from low-grade energy sources.

[1]  Nagamany Nirmalakhandan,et al.  Desalination at low temperatures and low pressures , 2009 .

[2]  Fawzi Banat,et al.  Economic evaluation of desalination by small-scale autonomous solar-powered membrane distillation units , 2008 .

[3]  Hui Tong Chua,et al.  New MED based desalination process for low grade waste heat , 2016 .

[4]  Hisham Ettouney,et al.  Performance of parallel feed multiple effect evaporation system for seawater desalination , 2000 .

[5]  H. Ettouney,et al.  Multiple-effect evaporation desalination systems. thermal analysis , 1999 .

[6]  William J. Cosgrove,et al.  World Water Vision: Making Water Everybody's Business , 2000 .

[7]  Nagamany Nirmalakhandan,et al.  Desalination Using Low-Grade Heat Sources , 2007 .

[8]  Salim Newaz Kazi,et al.  Study of mineral fouling mitigation on heat exchanger surface , 2015 .

[9]  He Weifeng,et al.  Performance analysis of an air-heated humidification–dehumidification desalination plant powered by low grade waste heat , 2016 .

[10]  Roberto Borsani,et al.  Fundamentals and costing of MSF desalination plants and comparison with other technologies , 2005 .

[11]  Swellam W. Sharshir,et al.  A continuous desalination system using humidification – dehumidification and a solar still with an evacuated solar water heater , 2016 .

[12]  H. Ettouney,et al.  Fundamentals of Salt Water Desalination , 2002 .

[13]  Ali M. El-Nashar,et al.  Cogeneration for power and desalination - state of the art review , 2001 .

[14]  D. Yogi Goswami,et al.  Analysis of an innovative water desalination system using low-grade solar heat☆ , 2003 .

[15]  A. Ophir,et al.  Advanced MED process for most economical sea water desalination , 2005 .

[16]  S. Bingulac,et al.  Steady‐State Analysis of the Multiple Effect Evaporation Desalination Process , 1998 .

[17]  Jianhua Zhang,et al.  Pilot trial of membrane distillation driven by low grade waste heat: Membrane fouling and energy assessment , 2016 .

[18]  Adewale Giwa,et al.  Humidification–dehumidification desalination process driven by photovoltaic thermal energy recovery (PV-HDH) for small-scale sustainable water and power production , 2016 .

[19]  Kyaw Thu,et al.  Adsorption desalination: An emerging low-cost thermal desalination method , 2013 .

[20]  Henry Shih.  Evaluating the technologies of thermal desalination using low-grade heat , 2005 .

[21]  M. Elimelech,et al.  The Future of Seawater Desalination: Energy, Technology, and the Environment , 2011, Science.

[22]  Seung Jin Oh,et al.  Recent developments in thermally-driven seawater desalination: Energy efficiency improvement by hybridization of the MED and AD cycles , 2015 .

[23]  D. Yogi Goswami,et al.  Theoretical Analysis of a Water Desalination System Using Low Grade Solar Heat , 2004 .

[24]  Nagamany Nirmalakhandan,et al.  Feasibility study of a new two-stage low temperature desalination process , 2012 .

[25]  Conor J. Walsh,et al.  Desalination using low grade heat in the process industry: challenges and perspectives. , 2012 .

[26]  Mohammad Sadegh Hatamipour,et al.  A review on energy consumption of desalination processes , 2014 .

[27]  He Weifeng,et al.  Thermodynamic investigation of waste heat driven desalination unit based on humidification dehumidification (HDH) processes , 2016 .