Experimental Study Of Sterilization And Descaling By Underwater High Voltage Pulsed Spark Discharge

Underwater high voltage pulsed spark discharge technology is a new type of water treatment technology in recent years,because of its cleaning,do not use any chemical agents,action mechanism of clear and so on,which is more and more popular with scholars.In this paper,taking E.coli[CMCC(B)44102]standard strain as the research object.Firstly,under the condition of static experiment,the effects of underwater high voltage pulsed spark discharge on the inactivation of E.coli are studied.Then using artificial simulated circulating cooling water as the research object,studying whether the underwater high voltage pulsed spark discharge combined with the mesh filter can reduce the scale of circulating cooling water in high concentration ratio.The results show that:(1)Under the condition of static experiment,the more discharge times,the larger the discharge frequency,the better the inactivation effect of the spark discharge on E.coli,but the greater the energy consumption,so the number of discharge and the discharge frequency should be selected according to the actual situation;The effect of discharge voltage on the sterilization rate of the spark discharge is the energy rather than the voltage,It is not realistic to improve the rate of spark discharge by increasing the voltage.If you want to achieve sterilization effect,you can properly improve the discharge energy;The effect of the main ions on the sterilization rate of the spark discharge is negligible.The best concentration range of the initial concentration of Escherichia coli for the discharge sterilization is 10~6CFU/mL.(2)Under the condition of dynamic experimental,the effects of discharge times,discharge frequency and discharge voltage on the discharge of water are studied,the conclusion is consistent with the static experiment.In addition,the effects of solution conductivity and initial pH value on the sterilization effect of spark discharge are studied,the results show that the smaller the conductivity of solution,the smaller the flow rate of circulating water,the weak alkaline solution,the better the inactivation effect of E.coli.(3)The comparison of sterilization effects between dynamic and static experiments shows that,under the same experimental conditions,the dynamic sterilization effect is better than the static,and the reactor for discharge sterilization doesn't have to be big.(4)Under the current experimental conditions,underwater high voltage pulsed spark discharge can effectively remove the scale of circulating cooling water with a concentration of 12,and the operation cost is extremely low,only 0.26%of the cost of saving water.