Capacitive desalination (CDI) fo r seawater desalination

1. Capacitive desalination (CDI) for seawater desalination Name:ZhangLiwen School: School of chemicalengineering and technology Number: 2012207148

2. 4. 5. 1. 2. 3. Introduction of capacitive desalination Situation of water resources Solutions to the problem Introduction of seawater desalination Conclusion Content

3. Situation of water resources The development of society Population growth

4. Situation of water resources Trash Truck Disposing of Garbage Pipelinedischarging sewage

5. Situation of water resources Highly Polluted River

6. Situation of water resources According to statistics, only 50% of people living in Central Africa can access safe water. The largest population without access to safe tap water is in China (25%)

7. Solutions to the problem Reducing water pollution Solutions Saving water Seawater desalination

8. Solutions to the problem What can we do about the water pollution? Protecting ourselves against polluted water. Not throwing trash or garbage into any stream or lake. Cleaning up polluted water First Second Finally

9. Solutions to the problem Saving water, begins frommyself. Don’t let our tears become the last drop of water on earth

10. Introduction of seawater desalination Definition Desalination is the process of removing salt and minerals from salt water to make it suitable for human consumption, irrigation and other fresh water uses.

11. Introduction of seawater desalination Saltwater is heated, evaporated and collected . Saltwater is forced through membrane sheets at high pressures Thermal Desalination Membrane Capacitance

12. Introduction of CDI Advantage Principle

13. Introduction of CDI Advantage Energy-efficient No pressure and heating Environment-friendly No chemical reagents

14. Introduction of CDI CDI reactors comprise pairs ofporous activated carbonelectrodes through which the brine flows.

15. Introduction of CDI Adsorption stage The cations in the aqueous solutionare adsorbed on the cathode and the anions are adsorbed onthe anode , leaving a deionizedsolution in the cell, which flows out as freash water. Adsorption Desorption

16. Introduction of CDI Desorption stage The electrodes are shorted,leading to ion desorption, thusformingconcentrated solutions that are expelled from the cellas waste. Desorption

17. Conclusion Desalination is useful in solving the problem of water shortage. CDI is regarded as a promising desalination process. Everyone has the accountability to save water and to propagate the concept of treasuring water.

18. Thank You !