Study On Synthesis Cationic Polyacrylamide And The Agents' Performance Of Treatment Of Oily Wastewater

There are many sources to produce large amount of oily wastewater.The oily wastewater forms a stable homogeneous phase system with the oil coexisting in a variety of forms,such as,water suspended solids,dissolved organic compounds,bacteria,etc.So the treatment of oily wastewater is very difficult.The development of high efficient flocculant of oily wastewater is the most effective and economical process in wastewater treatment industry.Cationic monomer?N,N-dimethyl-N-acryloyloxyethyl-N-benzyl?ammonium chloride?DBC?was synthesized via ester-exchange reaction and quaternization reaction.The characteristic functional groups of intermediates and products were characterized by nuclear magnetic resonance?NMR?and infrared spectra.With the reaction yield as index,the optimization for synthesis process of N,N-dimethylaminoethyl acrylate?DMAEA?and DBC were studied and the best reaction conditions were determined.Then the inverse microemulsion system was obtained with the conditions:DBC and acrylamide?AM?as monomers,isoalkane as dispersion medium,Span80-wt2524 as compound emulsifier,quality ratio of oil phase and water phase is 3:7,the composite emulsifier for 3.5%.P?AM-DBC?was synthesized by using KBrO3-Na2S2O5 oxidation reduction initiator in inverse microemulsion polymerization.Through the single factor experimental research,the effects of dosage,reaction temperature,and cation content on the molecular weight and conversion rate were systematically investigated,and the synthesis conditions were optimized.It takes these factors which the cationic monomer ration is 15%,the amount of KBrO₃ is 0.01%,the amount of Na₂S₂O₅ is 0.006%,the reaction time is 3hours,and the reaction temperature is 25?,as the P?AM-DBC?option conditions for synthesis.The relative molecular mass of P?AM-DBC?based on this synthetic condition is8.21 million and conversion rate is 99.5%.In the basis of AM and DBC inverse microemulsion polymerization system,acryloyloxyethyl trimethyl ammonium chloride?D-AC?was introduced as the third monomer,and on the basis of KBrO3-Na2S2O5 oxidation reduction initiator,tert-butyl hydroperoxide?TBHP?was introduced in this reaction system.The experimental results show that the addition of TBHP was benefit for the activation of the initiator system and improve the conversion rate.Through the flocculation evaluation experiment in laboratory,the effects of P?AM-D-BC?and P?AM-DBC-DAC?on treating waste water in Jinzhou Oilfield were investigated.The experimental results showed that P?AM-DBC?with 6.23 million molar mass and17.5%cationicity had a good flocculation effect,the turbidity removal rate was 95.6%and the oil removal rate was 94.0%when dosage was 25mg/L and pH is 5.When P?AM-DBC-DAC?was used to treat waste water in Jinzhou Oilfield,oil content and turbidity removal rate has been further improved.The two kinds of agents were contrast with other kinds of flocculants on treatment wastewater in Jinzhou Oilfield,that shows hydrophobic association CPAM in the lower cation degree can achieve the best flocculation effect and save the cost.P?AM-DBC?and P?AM-DBC-DAC?as coagulant,were respectively used with PAC and the effects of dosage,pH on flocculation performance upon waste water from polymer flooding in Daqing Oilfield were investigated.Finally,the heterotrophic bacteria sterilization experiment shows that the two kinds of cationic polyacrylamide medicament on heterotrophic bacteria had a certain role in the killing,and with the increase of dosage,the sterilization rate had increased.