Design And Experimental Study On The Oil-water Separator

At present,most of the oil fields in China have entered the middle and late stage of oil exploitation,the oil content of crude oil is low while the water content is 80% ~ 95%,some oil fields even reach to 98%.At the same time,national economy's blossom has been bringing soaring turnover in the catering industry,whereas,producing a large number of high concentration of oily wastewater,which is challenging the present oil water separation technology and equipment.Therefore,fining an effective way to separate the oil from the water so as to reduce the wastewater's environmental hazards and improve the utilization of recycled oil resources has become a hot issue for researchers.There are many oil and water separation technologies,including physical,chemical and biological methods.Among those treating methods,physical treatment has been widely used because of its inherent strength: no power consumption,no secondary pollution,low maintenance cost and so on.The combination of gravity separation and coalescence technology can enhance the oil removal efficiency to the greatest extent,which has good social and economic benefits and vast development value.Coalescence method is to add lipophilic or hydrophilic polymer material in the oil-water separator,through "collision" or "wetting" to achieve small oil droplets in water interception,aggregation and release?Currently,coalescence materials is rapidly developed,and now a large scale of coalescence tools can be chosen in different shapes and materials.They can be classified into two categories: discrete and regular coalescence materials.The author has designed a novel oil-water separator,which is mainly characterized in that it can perfectly adapt to the inflow by adding or decrease the number of columns flexibly,the oil and water fluid run in the same direction but collected in different zones,multistage settlement structure ensures the separation efficiency,small volume,simple structure and easy disassembly which makes it can easily be equipped to a water treatment vehicle and add different function with some fundamental modification,.Its drawback lays in the treating capacity for the volume of each column is fixed,meanwhile,the separation effect for small size oil droplet is in a moderate level.This paper will test the basic performance of the device and study how to improve it.Figuring out how the equipment react to different condition and study countermeasures.Through the trails,the best oil thickness was found.The separator's maximum and minimum water separation efficiency were achieved under 1~5 L/min's water flow oilwater ratio between 1:20~1:400;on the test to the best and worst group under coalescence,how much positive effect coalescence bring to the separation can be obtained.At the same time,author had studied the way coalescence affecting separation performance;in order to investigate whether the changes of series can improve the separation efficiency,this paper will also examine the influence on the separation efficiency of the series;it also discussed the effect of adding surfactant on the separation efficiency of equipment.The experimental water and oil were emulsified by the pipeline pump,and its emulsifying effect is stable in the whole test.Using standard spectrophotometric method to get the oil content's information,using Malvin Laser Particle Size Analyzer to find its particle size distribution,the experimental equipment functioned stable throughout the trails.The author chose polymer fiber ball as coalescence material,sodium dodecyl benzene sulfonate(SDBS)as emulsifier.When the water flow rate is 1 L/min and the oil/water ratio is 1:200,separation efficiency is the highest.The separator's can remove 10% ~ 30%'s oil form influx basically in 60 L/h ~ 300 L/h ‘s water intake.By adding coalescence materials with 93% porosity,the removal efficiency can be improved.Through experiments,three level's oilwater separator is reasonable,by changing the series to improve the its separation efficiency is not desirable in theory;the addition of a surfactant can cause significantly reduced in separation efficiency,even though adding coalescence materials in the separator,no obvious change were saw in the separation efficiency,some other ways should be come up with if aiming to improve the separation efficiency for this equipment in the presence of surfactant.