Experimental Studies On Oilfield Pipe Scale By Ultrasonic

At present, due to the high salinity within the pipeline of field in the country, the scaling is severe and difficult to be removed, causing a significant impact on safe oil production, Therefore it is necessary to carry out the research on the antifouling technology for oil pipeline. In the existing cleaning methods, mainly including chemical descaling cleaning and physical descaling cleaning.Because of the medium added material,Chemical descaling cleaning method may cause secondary pollution and do not meet the requirements of environmental protection, so this paper mainly studies the physical cleaning methods, namely the effect of ultrasonic cleaning and practical application parameters.In all types of scales in the oil field, the salt scale is the most common, the scope of the maximum. Ultrasonic has a poor effect on wax scale, grease and solid impurities containing more dirt.so the main research object of this article is the salt scale. Scaling in the pipeline comes from insoluble and soluble mixture in the injected water and formation water. The effect of ultrasonic on the mixed salt can’t be evaluated, so the effect of ultrasonic wave on different salt is mainly for a research on single salt scale. This paper on calcium carbonate, calcium sulfate, barium sulfate, strontium sulfate, the four kinds of common oil fouling was conducted in laboratory scale experiments and ultrasonic anti-fouling simulation experiment.Indoor simulation experiment of static scaling refers to coupon in the stationary state of fouling experiments. In the experiment, changing the scaling time 8,24,48,72 hours and the scaling degrees 40 ℃,60 ℃,80℃, as well as the junction between different materials coupon obtained Scaling amount under different conditions and finally focuses on temperature, pipes, and time on the fouling rate and amount of fouling.Ultrasonic anti-fouling simulation experiment instrument was improved on the basis of the China University of Petroleum (East China), Xu Zhenyu’s research Respectively at different frequencies 20 KHz,28 KHz,68 KHz,120 KHz ultrasound study through the ultrasonic cleaning tank at the bottom of the replacement to achieve. In the practical application of ultrasonic anti-fouling technology, the main research is the optimal parameters of anti-fouling instrument and under this circumstances the four single scale controlling effect. Using different transducers Ultrasonic studies scaling optimum frequency and Changes in the role of time researches the best ultrasonic antifouling irradiation time. Changing ultrasonic cycle obtains the optimal cycle of ultrasonic antifouling. Finally, using the above optimal parameters do experiment on the four scale.It was found in the experiments that better control effect of ultrasonic wave on salt scale, especially on calcium sulfate scale at 40 ℃ reached about 80% of the descaling. In the practical application, the frequency at 28 KHz has strong scale effect and ultrasonic time was 5 minutes when the best economic returns and the scale and crystal formation ability is weak; when the effect of ultrasonic cycle is 12 hours, antifouling ability is strong.