Research On The Scale Prevention And Removal Equipment Based On Ultrasonic And Electromagnetic

In recent years, with the ongoing process of water flooding, almost all oilfileds have entered in succession of high water-cut stage. Pipe scaling becomes more and more serious; scaling problem brings the influence on production and surface gathering system. So it makes important sense to research anti-scaling and descaling technology.This paper separately studies the mechanism of ultrasonic and electromagnetic anti-scaling and descaling. It analyzes the dynamic equation of cavitation bubble using MATLAB. Various factors influencing on ultrasonic anti-scaling and descaling are discussed. Finally it gets the best parameters. Using ANSYS to simulate the distribution of electromagnetic field in pipe, validate electromagnetic has the effect on scale prevention and removal. Based on the demand of scale prevention and removal equipment, design the circuit of ultrasonic part and electromagnetic part to achieve different control demand. Rectifier part of the main circuit adopts the chopper-type rectifying circuit structure, in order to achieve the purpose of regulating voltage and power. Ultrasonic part adopts the cascade multilevel inverter structure, uses non-PWM control method to control the multilevel inverter, to ensure high-frequency and high-power, the output is closed to sine wave which has the low harmonic content. As the square wave has the high harmonic content which can improve the effect of scale prevention and removal, electromagnetic part adopts the single phase half bridge inverter structure, which has the easy structure and convenient to control.This article also designs frequency tracking and Power controlling except the main designing about the power supply system. Frequency tracking adopts the maximum current feedback-DPLL method, in the big scope using the maximum current feedback method, in the small scope using the DPLL method. It improves the speed and also ensures veracity and accuracy of frequency tracking.This paper uses TMS320LF2407 DSP as control chip, designs related peripheral circuit, including sampling circuit, drive circuit and protection circuit. Based on the designing of hardware circuit, completes the PWM driver, frequency tracking, power regulation related programs.Finally, an experiment of ultrasonic-electromagnetic scale prevention and removal device is carried out using weight loss method. Experimental results show that ultrasonic or electromagnetic can achieve anti-scaling and descaling effect, but the effect of anti-scaling and descaling by ultrasonic-electromagnetic mixed field is more obvious and better than a single physical field, with no causing environmental pollution.