低温等离子体净化切削液废水的研究

Treatment of Cutting Fluid Wastewater by Non-thermal Plasma

为了探索处理切削液乳化废水新方法,采用低温等离子体技术处理,考察放电时间、废水pH、添加无机盐、电极间距、曝气量及电压的变化等因素。结果表明:随等离子体放电处理时间延长废水净化效率提高,最后趋于平缓;酸性条件有利于废水净化处理;添加少量无机盐可提高废水的处理效率,添加氯化钙的效果优于加入硫酸铝、硫酸亚铁、氯化钠;气相放电处理效果好于液相放电和气液两相界面放电处理效果;鼓入部分空气可提高废水的处理效果,鼓入空气量太大时,废水处理效率反而下降;随输入电压增大废水净化效率增加。最后得出:输入电压25 kV、电极间距35mm、曝气量0.2L/min、氯化钙加入量1.6 g/L,放电处理30min后COD和浊度最大去除率分别为90%和92%。

In order to discover a new method of treating cutting fluid emulsifying wastewater,non-thermal plasma technology was used.The influencing factors such as discharge time,wastewater pH,adding inorganic salt,electrode distance,airflow and different voltage were investigated.The results showed that effect of wastewater purifying ratio increases with prolonging plasma discharge time and tends to smooth finally;acidic conditions of wastewater is benefit to improve purifying ratio.Putting a little of inorganic salt can increase effect of wastewater purifying ratio,the effect of using CaCl2 is better than using Al2（SO4）3、FeSO4、NaCl.The purifying ratio of gas phase discharge is better then liquid phase discharge and gas-liquid interface.Putting air into the wastewater can increase the effect of treatment,but when the velocity of airflow is too high,the purifying ratio reduces.The purifying ratio increases with increase of input voltage.Final conclusion： when the input voltage was 25 kV、electrode distance 35 mm、airflow 0.2 L/min、CaCl2 1.6 g/L,discharge time 30 min,the removal ratio of COD and turbidity reached 90% and 92%,respectively.