WELL CASING CATHODIC PROTECTION UTILIZING PULSE CURRENT TECHNOLOGY

Materials and Corrosion, 2010

This paper introduces a comparative theoretical investigation of the conventional cathodic protection (CP) and the pulse cathodic protection (PCP) systems to show how both of them behave under different operating conditions. The effectiveness of the PCP system is also highlighted for a typical large-scale configuration as well as some field measurements have been carried out. The performance of PCP system has been analyzed in the light of getting better protection-current distribution along the protected well casing at reduced anode current together with reducing the stray current (corrosion) at any nearby unprotected structure(s). Many factors have been investigated to show their effects on the performance of the CP system, namely, soil resistivity, voltage pulse waveform and frequency, and multi-layer soil. In addition, the performance of both the conventional CP and the PCP systems has been compared to that when utilizing unused/abandoned well casing as anode energized by the conventional CP system. The PCP system shows better performance than that of the conventional CP, and a similar performance at high soil resistivity to that when using unused/abandoned well casing. On the other hand, the utilization of the unused/abandoned well casing gives superior performance, especially at low soil resistivities, where the protection-current profiles of both the conventional CP and the PCP systems decay sharply.

The cost of corrosion in the U.S. in 1986 was estimated to be close to $180 billion. Furthermore, estimates show that $70 billion worth of corrosion loss could have been prevented in 1986 by applying modern corrosion control technology. This section discusses the corrosion of metal in contact with moist soil or water, and the tendency of some metals to corrode preferentially with respect to other metals when located in the same environmental conditions. The use of a superimposed current to prevent or reduce the rate of corrosion by making the entire metal surface the cathode of an electrochemical cell and providing a separate anode is called cathodic protection. This section discusses the mechanisms of cathodic protection and the types of cathodic protection systems available for corrosion control. The different types of cathodic interferences are covered along with the safety considerations. A glossary of cathodic protection terms is also included. Sections 1200-1600 discuss specific applications of cathodic protection systems. The best cathodic protection system in the world is of no value if not properly checked and maintained. See Section 1800 on maintenance for details. Contents

This article discusses the use of CP (cathodic protection) for the cost effective control of external well casing corrosion. CP is an important tool because maintaining casing integrity is essential to oil and gas production, water and gas injection, and gas storage fields. When a leak develops, production (or injection) usually ceases until the leak is repaired or a liner is installed. When corrosion is severe, the casing can collapse and the well may have to be abandoned, which can result in lost reserves. CP can be utilized in maintaining casing integrity caused by external corrosion, thereby reducing operating costs and maximizing total production and profits.

2010

A project report submitted in partial fulfillment of the requirements for the award of the degree of Master of Engineering (Mechanical-Materials) Faculty of Mechanical Engineering Universiti Teknologi Malaysia APRIL 2010 iii DEDICATION To my beloved parents, siblings and friends for their endless loves and supports... iv ACKNOWLEDGEMENT Alhamdulillah, praise to be Allah, The Most Gracious and The Most Merciful. First of all, I would like to express my special thanks to Professor. Dr Esah Hamzah for her willingness to be my supervisor in this master's project. Your supports, encouragements, critics, guidance and friendship would never been forgotten. The opportunity to work under your supervision was a great experience. Special appreciations to Corrtroll company for the unconditional support, assistance and helps.My heartfelt thanks also to my parents and my siblings for the endless loves , supports, tolerance and understanding. In preparing this project report, I was very lucky to have chances to learn many new knowledge as this is a new field in corrosion protection and materials science and technology for me. Those experiences hoped to be used and fully utilized for my future undertaking. My sincere appreciation also extends to all my friends for the motivations and all the technicians in materials science laboratory and marine technology laboratory that involved in helping me to carry out all the laboratory works. v ABSTRACT Impressed current cathodic protection (ICCP) and coating give the optimum protection against corrosion for steel immersed in freshwater. This project presents the results of a study on the effectiveness of coating, impressed current cathodic protection and different environment conditions in preventing corrosion of steel.

International Journal of Electrical and Computer Engineering (IJECE), 2024

This paper introduces an innovative improvement to impressed current cathodic protection (ICCP) systems by integrating a pulse-feeding technique designed to address metal protection degradation during off-potential periods, a common issue in conventional systems. The proposed system enhances the overall effectiveness and reliability of ICCP, providing consistent corrosion protection for critical metal structures. A notable advantage of this method is its simplicity, utilizing a cost-effective microcontroller for pulse feeding. This approach simplifies integration processes and enhances cost-effectiveness, making it an attractive solution for improving cathodic protection system performance without substantial additional costs. The method addresses conventional ICCP weaknesses by applying a high-frequency pulse current during off-potential periods. This reduces excessive negative charge buildup on metal surfaces during interruptions, boosting the system’s effectiveness and stability. Research laboratory experiments were conducted using pulse width modulation (PWM) on an ATmega328P microcontroller to demonstrate the method’s effectiveness. Additionally, an IoT-monitored ICCP system was developed using an ESP32 microcontroller and the Blynk application. Results highlight the superiority of a 50 kHz pulse feeding frequency in preventing corrosion compared to lower frequencies. Overall, this advancement significantly enhances ICCP systems, providing improved corrosion protection and durability in harsh environments.