A selfdeveloped high⁃pressure CO2⁃crude mixing container is used to mix up CO2 and waxy crude oil respectively under reservoir condition, and gelling and yielding properties of the waxy crude oil are studied by gas chromatograph, DSC, rheological measurement, microscopic observation and other instruments. A brief summery about the effect of CO2 pretreatment on waxy crude oil was given. After treated by CO2, the reduction of light component in the waxy crude oil can inhibit the wax dissolution and increase the wax appearance temperature of waxy crude oil. The size of wax crystals becomes smaller and disperser after treated by CO2, which gives rise to the enhancement of the gel structure and the depravation of the low⁃temperature rheological property. With the increase of the pressure of CO2 during mixing process, the gelling and yielding properties of waxy crude oil are changed more and more obviously.

An experimental device for high water⁃cut crude oil is designed and built, which mainly includes test pipeline, oil⁃water separation system, data acquisition system and circuit control system. The test section is designed of organic glass tube with a water bath, which observes flow morphology and initial deposition process. Considering the working conditions in the production site, oil⁃water mixing device is designed by drawing lesson of the principle of jet mixer. In order to ensure the effective separation of free water and crude oil during the experiment, an oil⁃water separator suitable for high water⁃cut crude oil is designed on the basis of free water separator. At the same time, a data acquisition system and circuit control system are designed, which can effectively solve the problems of data acquisition and parameter control. After Experimental verification, the experimental device can fulfill the research work of flow and deposition of high water⁃cut crude oil.