Water in oil emulsion was used to capture CO2 from biogas (CO2/CH4) under hydrate formation condition. Span 20 was used to disperse aqueous phase or hydrate in oil phase. The influences of temperature

feed gas composition

pressure and water cut on the separation efficiency of emulsion were investigated. The separation ability of the absorption-hydration hybrid method was much better than that of the single absorption separation method

and uniform and flowable hydrate slurry could be obtained. The separation ability of the emulsion system increased with decreasing temperature or increasing water cut in specific ranges. Taking into account both separation efficiency and flowability of the slurry

the suitable operation temperature

pressure and water cut were determined as 270.15—272.15 K

around 3.2 MPa and 20%—25%(vol)

respectively. Under these conditions

after a two-stage separation

the content of CO2 in vapor phase could be reduced from 31%(mol) to nearly 10%(mol)

more than 87%(mol) CO2 could be captured by the slurry.