Sacrificial Anode Cathodic Protection Research Articles

Utilization of Sodium Polyacrylate Hydrogels in the Sacrificial Anode Cathodic Protection Method for Steel Members at the Atmospheric Environment

Utilization of Sodium Polyacrylate Hydrogels in the Sacrificial Anode Cathodic Protection Method for Steel Members at the Atmospheric Environment

Recovery and utilization of zinc dross for sacrificial anode cathodic protection of steel structures

Zinc dross is highly zinc-rich industrial waste produced during galvanization of steel. It is a byproduct of the reaction between molten zinc and loose iron particles in a molten zinc bath. Generally, 10–20% of galvanized zinc is converted into zinc dross. This work proposes a unique way of recycling of dross into a high value sustainable resource material leading to development of sacrificial anode used in cathodic protection of steel. The electrochemical behavior was studied in 3.5 wt% NaCl solution. The anode performance test was performed as per the standard DNV-RP-B401 in an artificial seawater solution. The performance parameters, (closed circuit potential (CCP), anode efficiency, and consumption rate) of the recovered zinc anode from dross, are close to the commercial zinc anodes. It satisfies the required anode criteria. Hence, the recovered zinc anode from dross could be used as a sacrificial anode for the cathodic protection of steel structures.

Perancangan Proteksi Katodik pada Tangki Olein Kapasitas 450 KL dengan Metode SACP

Cathodic protection is needed as corrosion mitigation in oil tanks on land to minimize internal and external corrosion. Corrosion problems that often arise in tanks are corrosion on the shell, roof and bottom. In this research, a corrosion protection system was designed for an olein storage tank with a capacity of 450 kL for one of the palm oil ship industries located in Kalimantan. The corrosion protection used is SACP (Sacrificial Anode Cathodic Protection) where active anodes are used to protect metal surfaces which are more passive against corrosion attacks. To provide good corrosion protection, sufficient current, number of anodes and correct placement are required. From the calculation results it was found that for the shell, the current required is 0.0102446 A with a total of 46 anodes and the placement of each anode is 5.36 m. For the same bottom and roof, each requires a current of 0.0103869 A with 7 anodes and a distance within a radius of 6.74 m.

Corrosion protection failure test analysis of the initial damaged cable ICCP mechanism

Given the corrosion protection failure of the cable-stayed bridge cable in the actual project, the impressed current cathodic protection (ICCP) technology was used to carry out the anti-corrosion tests from steel wire scale to cable scale, analyze the corrosion protection characteristics of steel wire ICCP, deduce the corrosion factor ICCP diffusion model, and reveal the space ICCP mechanism of the initial damaged cable. The analysis shows that ICCP can effectively inhibit the corrosive effect of steel wires and cables, and reduce the loss of mechanical properties of steel wires. Its protective efficiency increases with an increase in the absolute value of its protective potential and decreases with an increase in the dead load level. ICCP has a blocking effect on the diffusion of corrosion factors in the cable space, and the corrosion spatial distribution range, corrosion factor concentration, and diffusion coefficient of the initial damaged cable decrease significantly with the increase in the absolute value of the protection potential. The open circuit potential moves in a positive direction with the development of the corrosion process, and the blocking effect of corrosive factor diffusion is transformed from the joint participation by sacrificial anode cathodic protection and ICCP to the dominance of ICCP.

Fundamental study on cotton-like fiber acting as electrolyte carriers in the sacrificial anode cathodic protection system for closed-section steel structures under atmospheric environments

In the pursuit of sacrificial anode cathodic protection (SACP) for closed-section steel structures exposed to atmospheric conditions, a cotton-like fiber serves as the electrolyte carrier. The efficacy of this approach was validated through assessments of water absorption, retention, electrochemical properties, and SACP trials. The cotton-like fiber exhibited notable hydrophilic characteristics, absorbing nearly seven times its weight of the electrolyte and retaining over 50% of its maximum water absorption capacity after 15 days. Furthermore, the ionic conductivity of the fiber, when fully saturated with 0.1 wt% NaCl aq, was nearly twice that of the same concentration solution without fibers, diminishing as the electrolyte content decreased. Additionally, the open-circuit potential (OCP) of the Al-3Zn sacrificial anode was approximately −0.2 V relative to steel. Moreover, Nyquist plots revealed that electrodes in fibers were more resistant to dissolution compared to those in 0.1 wt% NaCl aq. In the SACP tests, the combination of cotton-like fibers with the Al-3Zn anode exhibited a protective performance for steel members, as assessed by the current density, instant-off potential, and steel surface conditions.

Development of Conductive Mortar for Efficient Sacrificial Anode Cathodic Protection of Reinforced Concrete Structures—Part 2: Four-Year Performance Evaluation in Bridges

This study explores the efficacy of a sacrificial anode cathodic protection (SACP) system with an activated carbon-based conductive mortar in bridge structures. In the previous Part 1 study, various admixtures were compared to identify a conductive mortar for enhancing the performance of the SACP system, assessed through electrical conductivity, resistivity, cathodic protection (CP) potential and current, and 4 h depolarization potential. Part 2 extends the investigation by applying the developed conductive mortar containing activated carbon to an SACP system on an actual bridge structure in which corrosion has already been initiated. Before CP installation, the physical properties of the conductive mortar were evaluated to satisfy the standard requirements for concrete structure maintenance. Subsequently, zinc mesh and bulk anodes were installed on the bridge pier, followed by the application of a conductive mortar with an admixture ratio of 5%. Over a four-year period, performance was measured through regular 4 h depolarization potential checks and visual inspections. The SACP system with the conductive mortar demonstrated superior CP performance compared to the general mortar, confirming the effectiveness of the developed conductive mortar. Visual inspection after four years confirmed the workability of the SACP system with conductive mortar.

Corrosion-resistant behavior and structural optimization of Ti/Cr, Ti/Cu, Cr/Cu, Ti/Cr/Cu multimetallic layer coatings in simulated seawater

This article is based on the sacrificial anode cathodic protection principle and the optimization method of multilayer structure. According to the standard electrode potential of metals, starting from the corrosion-resistant passive film formed by the metal itself, Ti/Cr, Ti/Cu, Cr/Cu, and Ti/Cr/Cu coatings were prepared on a 316L stainless steel substrate using magnetron sputtering technology. The corrosion performance of the coatings was studied to explore the interaction patterns between them. The results showed that in artificial seawater, the Cr/Cu, Ti/Cu, and Ti/Cr metal bilayer film coatings exhibited an increasing impedance arc radius and widening phase angle plateau in the electrochemical impedance spectroscopy. In the polarization curve, the self-corrosion current, the self-corrosion potential and polarization resistance are all better than the substrate. In the static immersion test, the weight loss rate of the metal multi-layer film gradually decreased, with all samples showing a lower weight loss rate in the second week compared to the first week, ranging from 27% to 52%. By further designing the microstructure of the coating to mitigate the contradiction between hardness and toughness, and reduce the generation of pores, the corrosion performance of the new Ti/Cr/Cu coating is significantly improved. The coating can repair surface defects of the material, fill in micro and nano gaps, and enhance the cathodic protection effect of sacrificial anodes.

Application of cathodic protection method on steel structures using sacrificial anode and sodium polyacrylate-sodium carboxymethyl cellulose (PANa–CMC) hydrogel electrolyte

An ionically conductive sodium polyacrylate-sodium carboxymethyl cellulose (PANa–CMC) hydrogel electrolyte was developed for the sacrificial anode cathodic protection (SACP) of carbon steel in high-humidity environments. The incorporation of varying ratios of CMC into hydrogel formulation enhanced the water retention capacity, adhesion strength, and electrochemical performance, making it suitable for SACP applications. Particularly, PANa-5% CMC hydrogels demonstrated a current density of approximately 3 μA/cm², inhibited passive corrosion product formation, and sequestered metal ions from anodes, thus minimizing contamination. These findings highlight the substantial potential of PANa–CMC hydrogels as electrolytes, expanding the application of the SACP method to atmospheric environments.

Effect of Zinc Addition in Filler Metal on Sacrificial Anode Cathodic Protection of Fin-Tube Aluminum Heat Exchanger

<p>This study investigated the tri-metallic galvanic coupling of different metals in the tubes, fillers, and fins of a heat exchanger. The goal was to prevent corrosion of the tubes using the fin as a sacrificial anode while ensuring that the filler metal has a more noble potential than the fin, to avoid detachment. The metals were arranged in descending order of corrosion potential, with the noblest potential assigned to the tube, followed by the filler metal and the fin. To address a reduction in protection current of the fin, the filler metal was modified by adding Zn to decrease its corrosion potential. However, increasing the Zn content of filler metal also increases its corrosion current. The study examined three different filler metals, considering their corrosion potential, and kinetics. The results suggest that a filler metal with 1.5 wt.% Zn addition is optimal for providing cathodic protection to the tube while reducing the reaction rate of the sacrificial anode.</p>

Effect of Nacl Solution on Protection Rate of BJTP 40 Steel (SNI 07-2052-200219) With Sacrificial Anode Cathodic Protection Utilizing Zn Anode

Reinforced concrete is a crucial element in infrastructure. However, it is unfortunate that the issue of corrosion in reinforced concrete structures has a significant impact and requires detailed consideration. Since the 1980s, research on corrosion-related problems has been initiated, one of which involves the SACP (Sacrificial Anode Cathodic Protection) approach using Zn sacrificial anodes. The purpose of this method is to control the corrosion rate in reinforced concrete. Environmental factors, such as the composition of solutions, play a role in influencing the resulting corrosion rate. Therefore, research is conducted by applying different solutions, namely 4% and 5% NaCl solutions, as well as Freshwater. This aims to compare the effects of these solutions on the measured corrosion rate using Zn anodes. The test results over a 4-week period indicate that the 5% NaCl solution exhibits a very high corrosion rate, as evidenced by the corrosion potential value of -790.3 mV. Conversely, the freshwater solution demonstrates a lower corrosion rate, with a corrosion potential value of -225.6 mV and a corrosion risk of only around 10%. This research provides a deeper understanding of the impact of solutions on the corrosion rate in reinforced concrete and offers a more scientific and contemporary perspective in line with current developments.

Analisis Penggunaan Cathodic Protection dengan Metode Sacrificial Anode Sebagai Pengendalian Korosi Pipa Minyak 16 Inci PT. Chevron Pacific Indonesia Simp. Perawang-Minas Area

Cathodic protection is a thermodynamic corrosion control method using metal as the cathode. There are two methods of cathodic protection, namely Sacrificial Anode Cathodic Protection (SACP) and Impressed Current Cathodic Protection (ICPP). This study will analyze the use of Cathodic Protection with the Sacrificial Anode method as corrosion control on a 16 inch oil pipe at PT. Chevron Pacific Indonesia. Carbon steel pipe (API 5L Grade B) with cast magnesium anode material. Calculation of anode requirement for corrosion prevention will be compared with actual field data within 10 years. The calculation results show that the number of calculation parameters used affects the results of the anode requirement on an oil pipe with a length of 16 meters, a diameter of 16 inches, anode with a length of 0.648 m, net weight of anode 7.7 Kg, magnesium anode material with an anode output of 10.8 A/m2, anode density 1765 Kg/m3, wear and tear (volume) 2296 x 10-3 m3 A/y, and a life time of 10 years. Theoretical calculations get 6 anode rods while the actual data requires 8 anode rods.

Examination of the Potential Effect of Corrosion Current Density of Ship Hulls on the Sacrificial Anode Cathodic Protection

In this study, the sacrificial anode cathodic protection system, which is one of the electrical protection methods in the prevention of corrosion in ships, was examined. Within the scope of the study, the potential effects of corrosion current density, which is an important parameter for cathodic protection design, were studied. The study includes cathodic protection calculations for a bulker with a protected hull area of 9406 m2 and a general cargo ship with a protected hull area of 1770 m2. As a result, it was estimated that each 1 mA/m2 change in the electric current density parameter changes the anode usage amount by 64 kg in bulker and 12 kg in general cargo, depending on the reference parameters such as protected hull area, anode type, and design life. It can be stated that the evaluation of the corrosion current density parameter, taking into account the operating conditions of each ship, will be beneficial in terms of optimizing the sacrificial anode consumption.

Modelling of 3D periodic cathodic protection problems in reinforced concrete structures with accelerated boundary element method

The steel used for concrete reinforcement exhibits either active or passive electrochemical behavior. As long as the concrete environment remains highly alkaline, the steel remains passive. However, carbonation and/or chloride contamination of concrete will cause steel to become active and corrode. In the latter case, a common strategy is the use of cathodic protection (CP) systems to lower the potential of the steel at a protective level. The numerical modelling of cathodically protected concrete buildings and infrastructures usually requires large-scale models due to their size and complex geometry. An efficient modelling approach is to consider any possible periodicity in these problems by applying periodic boundary conditions to a representative volume element of the structure. The boundary element method (BEM) is extensively used for solving CP problems. A BEM formulation is proposed for solving 3D periodic CP problems in this work. The computation cost is reduced by applying acceleration techniques based on adaptive cross approximation (ACA). As an engineering application, a sacrificial anode CP system of a reinforced concrete column is designed, illustrating the importance of detailed modelling in the design of such systems. To this end, the macrocell corrosion problem is initially solved, and a parametric study with respect to concrete conductivity is carried out.

A Study on the Applicability of Cathodic Protection for the Outdoor Sculptures Corrosion

In this study, we proposed the sacrificial anode cathodic protection method as a countermeasure to reduce the corrosion of the steel sculptures under outdoor conditions and proved the anticorrosive effect experimentally. To affix the Mg sacrificial anode and the steel plate specimen, an adhesive bonding strength test was conducted with three types of conductive adhesives. Hence, the suitability of the conductive epoxy adhesive was confirmed, and a C-clamp experiment was conducted to supplement the connection. In addition, by applying a sacrificial anode suitable for the soil where the artwork is installed, the field applicability was reviewed through an artificial determination of resistance to cyclic corrosion conditions test(salt fog/dry/humid) to prove the suitability of the cathodic protection method by sacrificial anode. Hence, corrosion monitoring is in progress by test-laying steel plate specimens in an outdoor sculpture park to identify natural deterioration. In the future, based on the results of the outdoor exposure test, we plan to determine the proper method of bonding the sacrificial anode and the steel sculpture, and the replacement period of the sacrificial anode.

Test Study of the Bridge Cable Corrosion Protection Mechanism Based on Impressed Current Cathodic Protection

The cable system is an important bearing element of a bridge with stay cables or slings and a matter of major concern in the safety of the bridge structure. Bridge cables are vulnerable to corrosion induced by leakage and soaking during their service life. To solve this problem, and based on the idea of proactive control by means of the impressed current cathodic protection (ICCP) of bridge cables, this study designs and develops an ICCP system device for bridge cable protection. In this study, an accelerated corrosion test was conducted to test the ICCP system of steel wires inside the cables and the cables under acid rain conditions. The corrosion protection behavior of ICCP was analyzed to reveal the corrosion protection mechanism of bridge cable ICCP. The results show that in the cable ICCP system, the impressed current generated by a more negative voltage may improve the efficiency of corrosion protection, but an excessively negative voltage may cause hydrogen embrittlement of the cable steel wire due to overprotection. The rational range of −1.13 V to −1.15 V was set as the result of the overall consideration. Within this range, the cable is subject to the joint protection of ICCP and sacrificial anode cathodic protection (SACP). Corrosive products can delay the development of cable corrosion to a certain degree; the SACP protection efficiency of the galvanized coat reduces gradually with corrosion development; and cable ICCP protection efficiency increases gradually. The ICCP for cable corrosion protection is transformed from joint protection using both a sacrificial anode and impressed current into protection, mainly using an impressed current.

Sacrificial Anode Cathodic Protection System Modelling Using Direct Boundary Element Method

Abstract Cathodic protection system is commonly employed approach for the protection of the metallic infrastructure placed in electrolyte against corrosion. Adequate design of the cathodic protection system requires the determination of electrical potential and current density distribution on the protected object surface that meets the defined criteria. In this paper, the application of the direct boundary element method in conjunction with Newton-Raphson method was considered for the calculation of the electric potential and current density distribution on the surface of the cathodically protected underground object. The considered method was applied on the sacrificial anode cathodic protection system of the underground pipeline. The non-linear boundary conditions of the electrode surfaces of the cathodic protection system are taken into account. The method was used to determine the current density and electric potential distribution on the external wall of the protected pipeline.

Development of Conductive Mortar for Efficient Sacrificial Anode Cathodic Protection of Reinforced Concrete Structures—Part 1: Laboratory Experiments

This experimental study proposes a conductive mortar to increase the efficiency of the sacrificial anode cathodic protection (SACP) system by decreasing resistivity and maintaining it for a long time. The resistivity characteristics of the mortar that contained electrically conductive admixtures and/or chemical agents were evaluated by the Brunauer–Emmett–Teller (BET) method and resistivity measurements. The conductive mortar with activated carbon and sodium hydroxide had the lowest resistivity. The SACP system was then designed to evaluate the cathodic protection (CP) performance with the proposed activated-carbon-based conductive mortar. The proposed conductive mortar contributed to lower CP potential and higher current density and depolarization potential than the general mortar.

The Effectiveness Evaluation of Sacrificial Anode in Reinforced Concrete that has been Installed for One Year

Generally, reinforcing steel in concrete is protected from corrosion. This happens because the cement content in the concrete has an alkaline effect. It can reduce the risk of corrosion, but the reinforcing steel may still corrode if exposed to a corrosive environment. One method of providing a high protection value against corrosion is the sacrificial anode cathodic protection system. This study aims to evaluate the effectiveness of the sacrificial anode cathodic protection on reinforced concrete. Three types of specimens were used in the study. The specimens were (a) unconnected anode-cathode specimen, (b) connected anode-cathode (design 1), and (c) connected anode-cathode (design 2). The dimensions of the concrete specimen are 1000 mm in length, 100 mm in width, and 100 mm in height. Profometer 5+ was used to locate the reinforcing steel in the concrete. In this study, the condition of the protected criteria of reinforced concrete was achieved within 30 weeks in 2019 after wet-dry cycle treatment in 3.5% NaCl media, and thus, the specimen was exposed in an open air for one year. In 2020, all of the specimens were treated again with a wet-dry cycle for 3 weeks to measure the potential value of the reinforcing steel after a year. The measurement result of the corrosion potential value after one year showed that the specimen (c) had a potential value of -884.67 mV. While the specimen (b) had a potential value of -689 mV. These results show that the specimen (c) still within the protected criteria based on the NACE standard after one year of exposure, whereas the specimen (b) is no longer protected after one year of exposure.

Combine merits of both sacrificial and impressed current cathodic protection in one system to mitigate chloride-induced corrosion in reinforcement concrete

Abstract The protection of Egyptian reinforcing concrete infrastructures from corrosion is a pressing and critical task for construction engineering and industry, particularly in coastal locations. The primary aim of this case study is to integrate the advantages of both sacrificial anode cathodic protection (SACP) and impressed current cathodic protection (ICCP) in a single cathodic protection (CP) system and to use the new system in Alamein New Place near the Mediterranean sea (Egypt). The results showed that the new cathodic protection system is running very well to protect the concrete iron bars from corrosion. With the passage of time, the protective system’s efficiency and stability improve. During 30 days, the zinc anode’s potentials remain much more negative, indicating that the zinc anode can retain strong electrochemical activity for an extended length of time. The application of the CP method decreases the corrosion rate of rebar steel in concrete samples over time, according to electrochemical impedance spectroscopy (EIS).

Effective Use of Sacrificial Zinc Anode as a Suitable Repair Method for Severely Damaged RC Members Due to Chloride Attack

In many cases, the repair strategy by using sacrificial anodes for cathodic protection in real RC structures requires additional zinc anodes after several years due to the decreasing protective area. This experimental study evaluates the effectiveness of time lag application of sacrificial anode cathodic protection applied to RC beam specimens that deteriorated severely due to chloride attack. In the experiment, sacrificial anodes and cathodic protection (SACP) were applied to 41-year-old RC beam specimens exposed to natural marine environments in which the embedded steel bars were significantly corroded. The repair work was performed in three stages. Instant-off and rest potential tests of steel bars were conducted periodically to demonstrate the time-dependent depolarization value. In the first stage, a polymer-modified mortar as a patch repair material was cast to replace the concrete in the middle tensile part with small sacrificial anodes embedded in the mortar. After the protective current reaches an equilibrium state, the sacrificial anodes are disconnected from the steel bars for a year, defined as the second stage. During the one year in the second stage, the steel bar in the patch repair area remained passive, without any sign of corrosion. As for the third stage, additional sacrificial anodes were installed in the existing concrete part to protect the steel in it. From one year of observation after applying sacrificial anodes to old concrete parts, the time lag SACP application of both in patch and non-patch repair parts was clarified to be effective in stopping the corrosion of steel bar in both parts until 20–30 years based on the service life prediction. Doi: 10.28991/CEJ-2022-08-07-015 Full Text: PDF