Experimental Study On Viscosity Reduction Of Heavy Oil Emulsion Under Pressure

Due to the growing consumption of conventional petroleum and natural gas resources,the huge conventional resources,such as heavy oil,get the developable potential.However,the high viscosity and poor fluidity,which are caused by the rich presence of asphaltene and resin,bring technical difficulties to oil recovery and pipeline transportation.Currently,the main pipeline transportation methods of heavy oil are heating,mixing with diluent and upgrading to reduce the viscosity.the the nano-particle as catalyst with microwave assisted is used to reduce the viscosity of heavy oil economically and effectively,which can lay a foundation for the field application.In this paper,the nano-particle as catalyst with microwave assisted is chosen as the main method for viscosity reduction.Firstly,the oil sample is tested to get its properties,which leads us determine the experimental parameters and their ranges.In addition to the three main factors,such as catalyst content,temperature and microwave power,water content and pressure are chosen for viscosity reduction tests.Response surface method is used to measure the viscosity reduction percent for different water contents and obtain the optimal parameter combinations.It is found that better viscosity reduction effect is shown for high water content oil samples,and it can be maintained for a long time.A series combination of catalyst content,temperature and microwave power is then tested to reduce the viscosity for different water contents under different pressures.The result demonstrates that pressure can slightly affect the viscosity reduction effect of microwave heating,but it can’t affect the viscosity reduction effect of catalyst.Lastly,based on the above experimental datas,the economic estimation manifests that nano-catalyst assisted by microwave has economic advantages under certain conditions.The mechanism of viscosity reduction for nanocatalysts assisted with microwave heating is investigated.The compositions of virgin and treated heavy-oil emulsions are tested through four-component determination method,infrared spectroscopy,elemental analysis and GC×GC/MS.The results demonstrate that the viscosity reduction is caused by the increasing of small molecule and decreasing of the macromolecular compounds.The characteristic functional groups don’t show significant change.But the proportion of nitrogen compound changes a lot,which decreases with the increase of water content.As a result,microwave heating and nano-catalysts have a synergistic effect to reduce the viscosity of heavy oil.