Thunyaluk Pojtanabuntoeng

• Fellow at Curtin University

Molluscan shellfish aquaculture contributes to 42.6% of global aquaculture production. With a continued increase in shellfish production, disposal of shell waste during processing is emerging as an environmental and financial concern. Whilst major commercial species such as Crassostrea spp. has been extensively investigated on usage of its shell, w...

Phenolic-epoxy coatings, which are designed to protect substrates from thermal damage, are widely applied in many fields. There remains an inadequate understanding of how such coatings change during their service life after exposure to various temperature conditions. To further elucidate this issue, this case study investigated the effects of high...

This paper investigated carbon steel corrosion in an enclosed environment, where one set of steel was immersed in 3.5 wt.% NaCl solution and another exposed to humid (condensation) conditions. The study employed electrochemical noise and electrochemical impedance spectroscopy techniques to monitor real time corrosion behaviour. The samples were eva...

This study evaluated the efficacy of a commercial volatile corrosion inhibitor (VCI) in mitigating the corrosion of carbon steel insulated with mineral wool insulation, especially as a retrofitted solution to CUI management. When VCI was added in dry insulation before the test solution was introduced, severity of CUI was reduced after 14-day exposu...

Coatings can protect metallic substrates (e.g., piping, vessels, tubes, etc.) against corrosion attack. The adhesion strength of a coating to its substrate is an essential factor that defines the overall coating integrity and performance. A pull-off adhesion test is commonly performed to determine the coating adhesion strength. This study evaluated...

Calibration of the non-destructive testing (NDT) methods for pipeline inspections is commonly done via machined defects with simple shapes and known sizes. However, such defects do not represent, e.g. an actual pit morphology observed in the field, which could lead to the unreliable interpretation of the inspection results. This work proposed a sys...

Corrosion under insulation (CUI) is defined as any form of external corrosion that occurs on the underlying metal beneath insulated equipment, due to water ingress through the insulation layer. This type of corrosion is frequently observed in oil and gas production, where insulated piping is prevalent, and has historically remained a predominant ma...

Monoethylene glycol (MEG) is often used to reduce the differential pressure across well valves so that they can be opened without damage. This MEG ultimately commingles with production fluids and if not deoxygenated contributes to the overall content of dissolved oxygen that may be seen by a receiving production facility. Normally, the dissolved ox...

Selective laser melting (SLM) or powder bed fusion is a type of additive manufacturing (AM) technology with applications in, e.g., the orthopaedics, energy, and aerospace industries. Several studies investigated the localised corrosion behaviour of SLM-fabricated Type 316L (UNS S31603) stainless steel. Little is known, however, about the effects of...

Top of the Line corrosion (TLC) is a serious concern in wet gas transportation pipelines operating in stratified flow regime. Extensive research on TLC has been conducted in hydrocarbon-free environments while, in production environments, condensable hydrocarbons are always present. When water and hydrocarbons co-condense, the condensate comprises...

Throughout the years, a vast number of chemistries have been identified to mitigate corrosion of various metals and their alloys in a wide range of environments, and corrosion inhibitor products play a critical role in protecting assets in many industrial applications. If the operational requirements are met, carbon steel is commonly the preferred...

In-situ monitoring of CO2 corrosion of carbon steel and FeCO3 precipitation, under continuous replenishing of condensed water conditions, was investigated using a newly developed electrochemical probe. Comparable results were obtained using electrochemical and non-electrochemical methods that validated the design and efficacy of the probe for monit...

This study aims to i) determine the dissociation constant (pK a) of acetic acid (HAc) in monoethylene glycol (MEG) which is used to calculate the relative amount of undissociated HAc at different pH, and ii) investigate the influence of MEG on CO 2 corrosion of carbon steel in the presence of HAc. The study reveals that MEG increases the pK a of HA...

Corrosion of carbon steel under mineral wool insulation was studied using the electrochemical current noise (ECN) method. Intensities of corrosion were validated using gravimetry, and the form of corrosion confirmed using optical microscopy. The standard deviation of the current noise signal agreed with weight loss results and was demonstrated as a...

The efficiency of hydrogen sulfide scavengers directly injected into gas streams is often compromised by short contact times due to space limitations on offshore assets. The use of static mixers is often employed to increase the efficiency of gas-liquid mixing. The performance of two commercially available hydrogen scavenger products were assessed...

Corrosion under insulation (CUI) of the piping systems has posed a significant threat to the safe and continuous operations of refineries and petrochemical processing plants, especially for the aged facilities. Detection of damage caused by CUI is very challenging due to its insidious nature. If left unattended, CUI could proceed continuously at a...

Microbiologically influenced corrosion (MIC) is a complex process that generates economic losses to the industry every year. Corrosion must be managed to prevent a loss of containment of produced fluids to the external environment. MIC management includes the identification of assets with higher MIC risk, which could be influenced by nutrient level...

The effect of sulphur compounds and temperature on the microbiologically influenced corrosion of carbon steel has been assessed using multispecies biofilms. Biofilm composition, community structure and activity level shifted in response to environmental conditions, which resulted in substantial differences in pitting susceptibility of carbon steel....

Crude oil and formation water in oil reservoirs host a variety of microorganisms. The community structure of these microbial populations depends on the environmental conditions. Petroleum reservoirs are generally characterized by high temperatures, favouring the activity of thermophilic microorganisms. Nonetheless, temperature decreases after the o...

This study presents the solubility of calcium carbonate in monoethylene glycol (MEG)/water solution at high temperatures and high MEG concentrations. The conditions simulate the water removal process During MEG regeneration. Solubility was measured by dissolution at equilibrium and the thermodynamic of dissolution process of calcium carbonate was a...

This study investigated the susceptibility to pitting corrosion of 316L in CO2 and N2 environments at temperatures from 30 to 80°C in 3 wt-% NaCl at pH 4. Results from cyclic polarisation technique confirm greater pitting susceptibility of 316L in the CO2 environment. Electronic properties and composition of the passive film were identified by elec...

The influence of monoethylene glycol (MEG) on the condensation process and corrosion behaviour of carbon steel is investigated. The results show that increasing MEG concentrations at the bottom of the line increases MEG co-condensation, reduces condensation rates and, consequently, uniform corrosion rates. However, localised corrosion occurs and pi...

Top-of-the-line corrosion (TLC) is a concern for subsea wet-gas transportation pipelines operating in a stratified flow regime. The insufficient volume of electrolyte at the top of the line combined with the low electrical conductivity of the condensed liquid has confined the majority of TLC studies to the weight loss method which only provides int...

50 and 80 wt.% monoethylene glycol (MEG)/water mixtures at pH 4 and 6 were tested under different hydrodynamic conditions to investigate the MEG effects on CO2 corrosion of carbon steel. At pH 4, the presence of MEG resulted in a lower and less flow-dependent corrosion current density (icorr) than those of aqueous solutions. Since MEG changed the p...

The effect of pH controlled by n-methyldiethanolamine (MDEA), partial pressure of CO2, and monoethylene glycol (MEG) on corrosion behaviour of carbon steel (X65) at 10 °C was investigated. Linear polarization resistance and electrochemical impedance spectroscopy techniques were used. The optimum pH which yielded reasonable corrosion rate reduction...

This study investigates the oxygen-scavenging behavior of bisulfite ions in monoethylene glycol (MEG)/water mixtures at concentrations commonly found in gas-transportation pipelines. Temperatures and pH values were varied. The influence of transition-metal (TM) ions to catalyze the bisulfite oxygen scavenging was studied. Experimental results indic...

This study investigates the influence of surface temperature and droplet retention time (DRT) on the corrosion rate, FeCO3 supersaturation, and scaling tendency of carbon steel exposed to water condensation. This corrosion phenomenon is also known as top of the line corrosion (TLC). TLC is found to be governed by surface temperature irrespective of...

Jacketing or a weather barrier is usually installed in insulated piping systems and pressure vessels to prevent water ingress and protect the insulation. In the event of water penetration and accumulation resulting from poor design and/or aging of the jacketing, drain holes are proposed to accelerate the water dry-out process. This study investigat...

Monoethylene glycol (MEG) is injected in the pipelines to prevent hydrate formation, and subsequent pipeline blockage. Recent investigations indicated that presence of MEG could impede CO2 corrosion of carbon steel, although many aspects remain unknown. In the current study, experiments were conducted at 80 °C (176 °F), atmospheric pressure, and 10...

Corrosion under insulation (CUI) has been one of the major causes of failure in the oil and gas industry. In most cases, progress of corrosion under the insulation is detected during routine maintenance and inspection. However in a few situations CUI is only realized detected after a failure and a significant loss of containment has occurred. Predi...

During the transportation of wet gas, temperature gradient between the internals of the pipeline and the outside environment leads to the condensation of water vapor. Freshly condensed water is very corrosive and can lead to the so-called Top-of-the-Line Corrosion (TLC). However, a certain fraction of hydrocarbons will co-condense along with the wa...

The effect of mercury on the corrosion of materials used for tubing in oil and gas production wells was studied. Carbon steel (L80) and 13% chromium stainless steel (13Cr) were selected for study by potentiodynamic polarisation. Simulated produced water, with the composition obtained from the Gulf of Thailand field, was used as a corrosive solution...

Top of the line corrosion (TLC) is a great concern in wet gas transportation where temperature gradient between the internals of the pipeline and the outside environment leads to the condensation of water vapor and a lighter fraction of hydrocarbons. Liquid water from the condensation is greatly corrosive as it is saturated with the acid gases; e.g...