In order to investigate the phenomenon of gas⁃liquid bias in parallel separators in oil⁃gas gathering and transportation system, an experiment facility for gas⁃liquid two⁃phase splitting was designed, constructed and instrumented. Flow rates, pressure, pressure drop，liquid level and liquid holdup were measured and recorded by data⁃acquisition system. Gas⁃liquid splitting pipelines of two geometries (horizontal pipeline⁃T junction⁃ horizontal pipeline and horizontal pipeline⁃T junction⁃vertical pipeline) were constructed. Experiments on splitting of slug flow were carried out and splitting characteristics of gas⁃liquid were studied with symmetrical and asymmetrical pipeline conditions. When the pipeline conditions are symmetrical, the two phases of slug flow splitting into two separators are even for pipelines of two geometries. When the pipeline conditions at the outlets of separators are asymmetrical, mal⁃distribution of both two phases occurs and liquid tends to split more evenly than gas. Based on the calculation of pressure drop, a splitting model was established and the influence of gas⁃liquid velocity on the flow characteristics was explained simply.

Using insulated tubing as production string is an effective measure to raise wellhead oil temperature and to reduce energy consumption of gathering and transportation system. Through investigation and analysis, optimization of aerogel as heat insulation material for insulated tubing, the thermal insulation effect of the insulated tubing is further verified by the measured data. Taking the actual oil well as an example, the governing equations of flow and heat transfer for down hole insulated tubing are established, the heat transfer characteristics of the insulated tubing are numerically simulated, and the influence of different insulation structures on the temperature drop of the oil flow in the pipe is studied. The results show that the four insulation structures meet the production requirements by using 6 mm,10 mm,6 mm+10 mm and 3 mm+10 mm, which provides a theoretical basis for the production of thermal insulation tubing by aerogel nano insulation materials.

Solvent refining of VGO No.5 using N-methyl-2-pyrrolidone(NMP) and furfural separately were studied. Based on the optimum operation conditions of NMP and furfural refining, simulating three stages about NMP and furfural extracting VGO No.5 and dewaxing the refined oil were carried out. The properties of refined oil and dewaxed oil were analyzed. The qualities of refined oil from single stage refining using NMP and furfural were closed to. The dewaxed oil of two can satisfy the indication of quality. For NMP refining, compared with furfural refining, the solvent to oil ratio dropped down 50% and the yield increased 7%. For simulating three stages refining using NMP, as compared to furfural, the solvent to oil ratio dropped down 50% and the yield increased 4%. The qualities of refined oils are closed to and better than these of single stage refining oils. The study show that NMP refining had a better result than furfural refining.