Study On Synthesis And Performance Application Of Microcrosslinked Amphiphilic Polyacrylamide

Considerable amount of oily wastewater and oily sludge,whose direct discharge will cause great harm to the environment,will be generated in the process of crude oil mining,storage,transportation,and refining.Therefore,it has become the current research focus to treat these two wastes efficiently and reasonably.In this thesis,the application performance of a series of amphiphilic polyacrylamide polymers synthesized by micro-crosslinking free radical polymerization for the treatment of oily wastewater and oily sludge was evaluated.The main work is summarized below:1.Cationic polyacrylamide(PADO)with excellent flocculation performance was synthesized via inverse emulsion free radical polymerization method by using acrylamide(AM)and N-acryloyloxythyl N,N-ethyl dimethyl N-benzyl ammonium chloride(DBC)as the main comonomer,while vinyl alkoxysilane as the copolymerization crosslinking monomer.The structure and molecular weight of PADO was characterized by analytical techniques including IR,1HNMR,and static light scattering,PADO was used to treat the oily wastewater with complex composition generated from the site of the Bohai K platform.The experimental results showed that the deoiling rate of wastewater could achieve 90%when the PADO dosage was 300 mg/L and the solution was kept at room temperature for 2 hours.Using a stability analyzer to analyze the flocculation process,it was found that the wastewater treatment process had a short flocculation time,and the system had a high instability coefficient.The treated flocs had appropriate floc strength and recovery factors.In order to reduce the cost of treatment and improve the flocculation effect,PADO and inorganic flocculant polyferric chloride are deployed together.The deoiling rate achieved over 90%by maintaining the mixture in room temperature for 2 hours with the dosage of PADO and poly iron at 40 mg/L and 100 mg/L,respectively.2.An amphoteric polymer PADSV with salt resistance,high temperature resistance and excellent flocculation effect was synthesized by micellar copolymerization with acrylamide(AM),methacry loyloxy ethyl trimethyl ammonium chloride(DMC),methacryloyl ethyl sultaine(SBMA)and vinyl triethoxy silane(VTEO3)as comonomers.The structure and molecular weight of PADSV were characterized by 1HNMR spectroscopy.PADSV was used to treat the oily wastewater with complex composition generated from the site of Bohai K platform,which was tested by the TD-500D oil in water analyser.It was proved that the oil removal rate achieved over 95%after maintaining at room temperature for 2 hours with the dosage of PADSV at 300 mg/L.The wastewater flocs obtained after the PADSV treatment have lower floc strength and higher recovery factor.3.A surface-active anionic polymer(PASV)was synthesized from acrylamide(AM),sodium p-styrene sulfonate(SSS)and vinyl triethoxy silane(VTEO3).Analytical instruments including 1HNMR spectrometer,Zeta potentiometer,and interfacial tensiometer were used to characterize the structural properties of PASV.Oily sludge treatment reagent consists of anionic polymer PASV3 and cationic polymer PAFC with a mass ratio of 1:1.In practice,the concentration of the reagent in the oily sludge was 2%wt/wt.Stir and stand to separate the oil phase,water phase and solid phase.Theexperimental results showed that the recovery rate of crude oil in the sludge achieved 94%,while the residual oil rate in both the solid phase and water phase were reduced to 1.14%.The synergistic use of the polymer PASV and PAFC achieved efficient three-phase oil-cement separation.By careful analysis of the change of reagent morphology,the content of carbon element,and the interface wettability contact angle,a preliminary analysis of the three-phase separation mechanism was conducted.