Research On Sewerage Treatment From Polymer Flooding By Ultra-Hydrophobic Mesh Filtration

During the past 20 years,polymer flooding has become a successful Enhanced oil recovery(EOR)technique for the mature reservoirs with high water cut and high recovery percent in the world,particularly in China Daqing oilfield.Nevertheless,sewerage from polymer flooding cannot be treated using conventional techniques.Moreover,the discharged water must meet more stringent waste disposal regulations imposed by local,national and international authorities.Consequently,efficient removal of oil from the polymer flooding produced sewerage still has drawn significant concern.In this work,in order to treat the sewerage from polymer flooding produced fluids,a high flux ultra-hydrophobic copper mesh was prepared using two-stage processes;immersion in the coating solution and finally treated with stearic acid.The surface of the ultra-hydrophobic mesh was characterized using various techniques such as SEM,OCA 20-contact angle goniometer,durability,and intrusion pressure tests.It was found that the static contact of the angle of the ultra-hydrophobic copper mesh was reached up to 165~o while the role of angle is 2~o with a 5-k Pa intrusion pressure.After characterization of the mesh surface,the ultra-hydrophobic mesh separator was assembled.The oil removal efficiency of the ultra-hydrophobic mesh separator for both kerosene and crude oil based sewerage is above 98%with oil purity>99.9%.The performance of the mesh was also evaluated under different internal and external factors such as oil to water ratio,oil type,viscosity,mesh pore size,polymer concentration,shear rate,salinity,and p H of the wastewater.The mesh can maintain its ultra-hydrophobic characteristics under extreme salinity and p H conditions.In addition,the mesh can be a potential candidate for the treatment of both polymer-free and a polymer-containing crude oil based sewerage.The configuration and separation mechanism was further explained in detail.