Performance Evaluation And Formular Adjustment Of Paraffin Remover/Inhibitor For Changqing Waxy Crude Oil

Wax deposition in oil well is key problem which leads to the descent of productivity and the risen of cost during the oil production process. The crude oil and paraffin from five different block of Changqing Oilfield were investigated in this paper to solve the above problems, some experiments on crude oil and paraffin properties, such as rheological property, composition of the crude oils, non-oleaginous composition and the DSC thermal characterizes, were carried out and the results show that all of the oil samples are acidic and the wax content, salinity and water content of Changqing crude oil are higher than that of other Oil fields. The high content of asphalt and non-oleaginous composition in crude oil may be the main effect for paraffin remover. The treatment agent was screened by single factor experiments based on above experimental results, then combined by uniform design experiments repeatedly, finally, the suitable formulas of oil-based and the emulsion paraffin remover were optimized for Changqing crude oil.The effect of paraffin remover was evaluated under laboratory experimental condition, it was shown that the effect of oil-based paraffin remover to Changqing crude oil performed well. The highest paraffin removal efficiency is97.13%per hour at45℃. Furthermore, the concentration of benzene in oil-based paraffin remover is less than6%. Compared to the same type paraffin remover of Changqing oil field, it reduced the toxicity of paraffin remover and secondary pollution for containing aromatic hydrocarbon bringing to post-treatment of oils; the paraffin removal effect of emulsion paraffin remover is also higher than other reported paraffin remover, but its stabilization is not well enough and hard to store. The efficiency of oil-based paraffin inhibitor are all exceed to65%for most oil sample, among which water-based paraffin inhibitor is more fit for high salinity oil, but the oil-based paraffin inhibitor influenced by the content of gum and asphalt severely in crude oil, except for the acidity and alkalinity of crude oil.