Applied Research Of High Voltage Electric Field In Lubricant Purification

With the rapid development of the national economy,our country's consumption demand for lubricants has grown dramatically.Because of the moisture and other impurities infiltrated inevitably in the course of using lubricants,the physical and chemical properties of lubricants are reduced and the lubricant becomes wasted.However,the improper disposal of waste lubricant,like discarded or burned directly,not only causes waste of resources,but also leads to serious pollution to the air,water and soil.In all kinds of pollution of lubricant,the emulsifying water is very hard to be removed using traditional centrifugal separator because its droplet size is too small.Before the traditional centrifugal separator,this paper uses high voltage pulsed electric field to pre-process the waste lubricant to improve the overall purification and dehydration.To demonstrate the effectiveness of high voltage pulsed electric field,this paper first studies the effect of purification and dehydration under high voltage pulsed electric field and the dynamic change of water droplets under electric field.By comparing the effect of purification and dehydration under different electric fields,high voltage pulsed electric field is chosen to be the right one.After exploring the high voltage pulsed electric field parameters(voltage,frequency and duty ratio)on the influence law of waste lubricant purification and dehydration,this paper concludes that as they grow,dehydration will increase first and then decrease,and there exist the optimal electric parameters which can be obtained by theoretical calculation.Furthermore,this paper does the dynamic research of water droplet including the force analysis(electrostatic force,resistance,gravity,buoyancy and internal and external pressure),the induced polarization deformation,coalescence demulsification and migration patterns.By building the experimental platform and designing the experimental flow,it has been demonstrated that it is effective for high voltage pulsed electric field pretreatment technology and it is founded for the law effect of frequency and voltage on purification and dehydration under high voltage pulsed electric field,which are in accordance with the above theoretical analysis.Besides,the optimal electric parameters are also obtained to support the engineering application.The experimental platform includes high voltage pulsed electric field power,new electrostatic coalescer indoor rapid evaluation device,GHP80 centrifugal vacuum oil purifier,cooling device and RIGOL DS1202CA digital oscilloscope and high voltage probes.Based on the emulsion of 50 L46#lubricant and 500 ml water as experiment medium,the data will be recorded once in a while including the bright time,the amount of separated water and voltage.After analyzing the data,it is concluded that(1)High voltage pulsed electric field improves effect of purification dramatically.The average purification time was reduced by 661.7 min the purification efficiency was improved by 178.1%,the average amount of dehydrated water was increased by 81.3 ml,the result of purification was improved by 27.7%(based on 1500 Hz);(2)The purification dehydration rate increases first and then decreases with the increase of the frequency and there exist the optimal electrical field parameters(1500 Hz),which is in accordance with the theoretical analysis;(3)Under 3100 V,with the increase of voltage,the purification and dehydration has been increased.According to the theoretical inference,the optimal voltage should be larger than 3100V.(4)Comparing the voltage and frequency,the effect of purification and dehydration on frequency is larger than that of voltage.