After the application of a non?ionic polyether clear water agent in an oilfield in the Bohai Sea,the difficulty of dewatering crude oil in the downstream terminal treatment plant increased,and the water content of the outgoing crude oil frequently exceeded the standard.The Effect of nonionic polyether water clarifier on crude oil dehydration was researched,the reasons of difficulty in dewatering were analysed,and the emulsion could not be treated by conventional polyether demulsifier.Polyamines were synthesised from dimethylamine,dodecyl dimethyl tertiary amine and epichlorohydrin,while polyethylene?polyamines were used as cross?linking agents to synthesise polyamine copolymer emulsion breakers.The emulsion breaker can reduce the water content of the external crude oil to less than 0.5% at a concentration of 80 mg/L,and reduce the static dewatering time of the crude oil from more than 120 h to less than 48 h.This effectively solves the problem of excessive water content in the external crude oil of the terminal treatment plant.

In order to study the influences of swing, H₂O and N₂ on the removal of CO₂ from offshore natural gas by adsorption and purification, dynamic penetration experiments of mixed multi?component gas in the dry and aqueous 13X zeolites under static and swing conditions were carried out. Mixtures of CH₄/ CO₂ and CH₄/ CO₂/ N₂ were obtained by matching CH₄, CO₂, and N₂ in proportion through a mass spectrometer. In addition, under static and swing conditions, the partial pressure of each gas in the mixtures at the exit of the dry and aqueous 13X zeolites at different time was measured during dynamic penetration experiments, and the penetration curve and penetration time were obtained. The adsorption and purification effect of CO₂ in the two mixtures in the dry and aqueous 13X zeolites under the two conditions was analyzed according to the penetration time, and then the influences of swing, H₂O and N₂ on the removal of CO₂ from offshore natural gas by adsorption and purification were clarified. The experimental results show that 13X zeolites have the strongest capacity in absorbing CO₂ and the weakest capacity in absorbing N₂ under static or swing conditions. N₂ is conducive to the removal of CO₂ from offshore natural gas by adsorption and purification, while the swing and H₂O fail to do so.