The Development And Application Of Paraffin Remover And Inhibitor Of High Pour Point Crude Oil In Dongsheng Oildom

With the reason of the flow-ability of high pour point crude oil was bad at low temperature and high wax content, the oil wells were easily blocked at room temperature, so the research of high pour point crude’s paraffin removal and prevention mode has become the main topic of this study. This paper was mainly aimed at high pour point crude oil in weibei area in shengli oil field, we conduct paraffin remover and inhibitor laboratory screening and performance evaluation, analyzed the IR, XRD and structural state of paraffin before and after adding reagents; Also we created a good depressive effect’s depressant to counter the carbon number distribution of oil sample, and optimized the conditions for pour point depression, finally through the viscosity-temperature curve、rheogram、the heat flow and the wax crystal morphology of high pour point crude oil before and after adding pour-point depressant, analyzing the mechanism of pour point reduction, provided a theoretical guidance for the solution of blocked oil wells.The selected formulations of paraffin remover and inhibitor by experiment(mass fraction): Benzene and toluene 89 %、EVA4260 5 %、EVA19400 5 %、TA1031 0.5 %、OP-10 0.5 %, this formulations has good paraffin removal and prevention effect, and every indicators were qualified, the wax cleaning effect was most remarkable, wax dissolving rate was 0.0829 g/min as more than 5 times than the industry standard; paraffin removal rate was 45.8 %, 15.8 % higher than the industry standard; viscosity reduction rate was 71.4 % at 48 ℃, pour point reduction range of crude oil was 5 ℃. The result after adding pour-point depressant shows that, infrared absorption peak area ratio of the paraffin increased, intensity of X-ray diffraction peak weaken. In the cooling process, wax crystal morphology changed into spherical flocculating constituent from a large number of irregular shape small particles, analyzed of growth in the wax crystal phase, adsorption-eutectic mechanism played a good role of paraffin prevention.According to the number of carbon distribution of high pour point crude oil, to synthesize AMV-22, with EVA mixture as raw material, when the heat treatment temperature of crude oil was 75 ℃, the total dosage was 1 %, at the same time added SLA-107 with 1000 mg/L, it could make the pour point reduction range of crude oil in 11 ℃, then achieved the best depressive effect. The viscosity-temperature curve result of crude oil showed that, pour point depressant could greatly reduce the pour point and viscosity of crude oil, but has a little decrease of the wax precipitation point; The rheological diagram showed that shear thinning effect of crude oil was more obvious when the temperature was higher, and when the shear rate was higher than 100 s-1, viscosity was little changed, also the oil yield stress was greatly reduced after adding the pour-point depressant; The heat flow result of crude oil showed that, pour point depressant was not to reduce the precipitation amount of wax to influence the pour point, but to change the wax crystal morphology to influence the pour point, this was because the finally accumulated wax precipitation volume were 29 %, there was no difference between before and after adding pour-point depressant. The microscope photos showed that, after adding pour-point depressant, three-dimensional network structure of wax crystal was destroyed more obviously, especially at the low temperature, wax crystals became more compact and approximately spherical, flow resistance of crude oil was reduced, so the aggregation of wax crystals and the formation of three-dimensional network played a decisive role on the pour point of crude oil.