| With the rapid growth of global population,abnormal changes in climate and environment,increasing energy demand and pollution and waste caused by poor management,the shortage of freshwater resources has become the most important survival crisis facing mankind.In the face of the increasingly severe water resource crisis,researchers all over the world are seeking solutions.Among them,relying on desalination technology,converting abundant seawater into fresh water that can be used by people becomes one of the most possible solutions.Compared with traditional seawater desalination technologies such as thermal technology method and membrane method,as a new type of seawater desalination technology,has the advantages of simple operation,low energy consumption and green environmental protection,and has attracted more and more attention from scholars at home and abroad.Two models for CDI simulation are introduced,one is based on the first-order reaction kinetics model and the other is based on the molar purification rate model.Through comparative analysis,the physical meaning is selected,which can be used to study the influence of various factors on the process.It is more suitable for the molar purification rate model of the simulation and analysis of the process,and the resistance of the model desorption stage is corrected to make it more in line with the actual situation.Then the simulink simulation model of seawater desalination is established through the selected model.According to the Simulink simulation model,the influence of each parameter on the minimum effluent concentration was studied.The results show that the minimum effluent concentration decreases with the increase of voltage and capacitance,increases with the increase of flow rate,channel volume and dead zone volume,and the time spent in adsorption phase increases with the increase of voltage and capacitance,decreases with the increase of flow rate and channel volume,and almost remains unchanged with the increase of dead zone volume.According to the water production efficiency and energy consumption,the parameters were optimized,and the result was the best when the flow rate was 0.5mL/s and the loading voltage was 1.2V.Using the established mathematical model,the design of 500L/d capacitive desalination unit was carried out.The treatment capacity of the device was 500L/d.The process is as follows.About 30 devices with 10 serial channels are operated at the same time.After 11 minutes of adsorption,they are then re-energized for 2 minutes for regeneration,and finally backwashed for 3 minutes to complete a processing cycle.The experimental device was made to test and optimize the operating parameters of NaCl solution with different conductivity.When the conductivity is 3000?S/cm brine,if the high water yield is pursued,the operating parameters are set to 1.2V for forward and reverse charging,700mL/min for flow rate,and 738.7L/d for water production.If low energy consumption is pursued,the operating parameters can be The positive and negative charging voltage is 0.8V,the flow rate is 650mL/min,and the water production is 526.56L/d.When the treatment conductivity is 10000 ?S/cm brine,the preferred operating parameters are: positive and negative charging pressure is 1.0V,influent flow rate is 450mL/min,and the obtained water volume is 370.32L/d.When the conductivity is 35000 ?S/cm brine,the high positive and negative charging pressure and the appropriate flow rate are desalted to medium and high concentration,and then the parameters are optimized. |
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