The Oil Sand Cold Production Of The Mathematical Model And Its Application

The cold heavy oil production (CHOP) is a new way of exploiting the heavy oil reservoir, which is originated from Canada at the end of the 1980's. Nevertheless, there are many aspects to be perfected, especially in the mechanism of the CHOP, which almost is blank in China. Based on the mass conservation principle and Darcy' flow principle, only considering the effect of the continuous sanding on enhancing the oil rate, this paper studies the mechanism of the CHOP deeply, and comes to the following conclusions:Firstly, the definition of the seepage flow velocity is corrected, and based on the mass conservation principle in the fluid mechanics; the concept of the mass density is extended from non-porous media to porous media, so that the general mass conservation equation is obtained.Secondly, the CHOP model is constructed under the conditions of the single phase and incompressible fluid in rigorous porous media. The model consists of three continuous equations, Darcy equation, sanding equation and supplementary equations (permeability equation, gorp viscosity equation and the equation of the relation between the real velocity and the seepage flow velocity). Then the model is solved in one-dimensional flow and radial flow conditions respectively. So we can get some variables related to the time t, such as the sand concentration, oil rate, sand rate, the variation of the porosity and the skin factor.Thirdly on the foundation of comparing the results of the model with the experience in oil field, and the reliability of the model is proved. In addition, the mechanism of the CHOP can be realized more clearly.Then, it is analyzed that the effects of the heavy oil's viscosity and the formation cementation (reflected by the sanding factor) on the achievement of the CHOP. And this is favorable when deciding a reservoir is whether applicable to the CHOP or not.The last, the defects of the model are discussed in detail, and the development of the model is looked to the future in oneself opinion. Moreover, the ideal of the limited sanding is put forward.It is believed that the research on the mechanism of the CHOP in the paper is the theoretical basis of modeling and forecasting the production when the reservoir is exploited by the CHOP. And also, the theoretical foundation on the mechanism of the CHOP can be found out in the paper, finally some new realizations are got.