Shengli Crude Oil Additives Modified

Energy saving and safe transportation of the crude oil with the easy solidification and high viscidity have been the major technological challenges that that oil storage and transportation sector has to face. After more than 40 years of unremitting efforts, great achievements in this field have been made in our country, but many technological difficulties in the energy saving and safe transportation of Shengli crude oil with the high wax content still have remained to be solved at present. Because Shengli crude oil much gelatinous components that have bad influence on the effectiveness of adding agents, it is difficult to to significantly improve the flowability of Shengli oil only by using the common adding agents. In order to reduce the consumption at the oil transportation process and to decrease the capital cost for new construction of the second or third time infilling wells and the cost of oil production, we focused on the preparation and application of the normal temperature and low temperature adding agents for Shengli crude oil. At the present time, Construction Design and Research Institute of Shengli Oil Field has produced three different chemical agents applicable to the normal atmosphere temperature or low-temperature oil transportation in different regions of Shengli Oil Field, named VOE series flow improver for crude oil. After the crude oil flow improvers were applied in the transportation of Shengli crude oil, the transportation oil temperature decreased to a considerable degree, and economic effectiveness was also greatly promoted. The flow in the pipeline of the pseudo emulsion that formed after addtion of the VOE series flow improvers is a new phenomenon in petroleum recovery and oil and gas gathering. In comparison with conventional flow of oil-water mixture, the use of adding agents not only can decrease the cold start pressure very obviously, but also greatly reduce the on-way resistance along the pipeline. However, the mechanisms of this flow phenomenon and the quantitative relationship have not yet been solved, this thesis will investigate the cold start pressure rules and the on-way resistance rule to flow along the pipeline after quiescence and stratification of the oil-water pseudo emulsion, thereby providing the theoretical basis for adding flow improver to achieve the normal atmosphere temperature and low-temperature oil storage and transportation. In this thesis, we mainly studied the action mechanisms of the flow improvers, the factors that affected the cold start-up pressure gradient, the on-way resistance pressure drop and the viscidity influence factors, and the possible results caused by these factors. Based on the theoretical simulation, we determined the fluid type of pseudo emulsion, established the formulae for pressure drop and viscosity, calculated the experimental data, and in-depth discussed the rheological characterization of oil-water mixture after adding the flow improvers.