Study On Structural Characteristic Of Heavy Crude Oil And The Preparation Of The Viscosity Reducer

Heavy crude oil is characterized by their high viscosities and low-degree API gravities. It is difficult to exploit because of its bad fluidity. The fluidity of the heavy crude oil is improved by adding various kinds of flowing remover in the course of its expoliting, transportation and refinery.It is necessary to investigate the chemical component and structure of the crude oil deeply if improving the fluidity of the heavy crude oil. The resin and asphaltene in the Wangzhuang heavy crude oil is composed by armotic structure by the analysis of UV and floresence spectrum. The conjugated aromatic rings in unit sheet are mainly three rings or four rings, whose connection is linear order, namely cata-condenesed The difference between asphaltenes and resins is that the resin has mainly less than five aromatic rings in conjugated aromatic unit and the asphaltene has more than five aromatic rings.In order to find out the polarity and the distribution of number of the aromatic ring in the asphaltenes and resins the asphaltene and resin in the Shengli viscous crude oil have been studied by FT-IR, UV-VIS spectrophotometry and synchronous fluorescence spectrometry. The results of FT-IR spectrum show that the molecules of the asphaltene and resin include hydroxy, amido, carboxyl, carbonyl which can produce hydrogen bond. It shows that there is the strong hydrongen bond interaction between the molecules of the asphaltene and that of the resin. It is the heavy components(the stucture of the resin and asphaltene)which brings the property of the Wangzhuang crude oil, such as high viscosity and density.In order to find out the reasons of the high viscosity of the Wangzhuang crude oil some experiments have been done. The experiments include the following infactors which influence the the viscosity of the crude oil. The infactors are the content of the heavy metal element, the concentration of the resin and asphaltent, temperature and diluent. The result shows that the amount of the heavy metal element V and Ni is the important factor which result in the high viscosity of the Wangzhuang crude oil. The concentration of the asphaltent has a very important inflenence on the viscosity of the crude oil. The viscosity of the crude oil increases with the concentration of the asphaltent. The concentration of the resin has a complex inflenece on the viscosity of the crude oil. When the concentration of the resin is low the resin can reduce the viscosity of the crude oil because of its despersant effect in the micellar structure of the crude oil solution. But the viscosity of the crude oil increase sharply the when the concentratio of the resin is above 50%. The reason is that the viscosity of the resin itself can increase the viscosity of the crude oil. The viscosity of the crude oil increases sharply, it shows that the mass fraction of the resin has a great influence on the viscosity of the crude oil.Temperature has a great influence on the viscosity of the crude. The viscosity of the crude oil reduces exponentially with the increase of temperature, but reduces slowly when temperature is above 50°C.The diluent has a great inflence on the viscosity of the crude oil, too. It reduces sharply with the diluent increasing, but reduces slowly when the diluent is up to a constant.The usual expoition has little effect on this kind of high viscous crude oil. The viscosity can be reduced only when some viscosity reducers are added so that the heavy crude oil can be exploited and trasnported easily. The polymer viscosity reducer is developed to deduce the viscosiy of the Wangzhuang crude oil. But the polymer viscosity reducer has a little inflence on the Wangzhuang heavy crude oil.The emulsifying viscosity reducer has been used widely because it has an evident effect on the crude oil. The emulsifying viscosity reducer JDLH has been chosen by the way of uniform design. The viscosity of the Wangzhuang heavy crude oil is reduced when adding JDLH viscosity reducer. It is a kind of the viscosity reducer which is used conveniently and economically.