Article
Construction & Building Technology
Kaiyang Li, Yimin Zeng
Summary: In this study, the corrosion and stress corrosion cracking (SCC) behavior of X65 steel in H2O-saturated supercritical CO2 (s-CO2) containing SO2 and O-2 impurities were investigated. It was found that X65 steels experienced severe corrosion and formed a porous corrosion layer composed of iron sulfates, carbonates and oxy-hydroxides. The mass loss of X65 steel increased linearly with exposure time in the s-CO2 environment. Timely replenishing s-CO2 fluid is crucial for accurately determining the long-term corrosion kinetics. Factors such as SO2 content, H2O content, and addition of NO2 were found to affect the long-term corrosion rate, which was described by a power-function-based empirical model.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Energy & Fuels
Jia Liu, Dengzun Yao, Kai Chen, Chao Wang, Chong Sun, Huailiang Pan, Fanpeng Meng, Bin Chen, Lili Wang
Summary: The corrosion behavior of X52 pipeline steel in supercritical CO2 streams containing impurities was examined, with particular focus on the effect of water content. It was found that the impurities and water content significantly influenced the corrosion process of the steel.
Article
Engineering, Environmental
Guoxi He, Qing Zou, Kexi Liao, Jihui Leng, Shuai Zhao
Summary: The corrosion mechanism and failure behavior of 20 G steel in a high-pressure CO2/O-2/SO2 steam environment were studied. The influence of temperature on film formation kinetics was found to be greater than that of cathodic reaction thermodynamics, and the interaction between H+ and Cl- led to degradation of mechanical properties.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2022)
Article
Materials Science, Multidisciplinary
Chong Sun, Xianglin Yan, Jianbo Sun, Jianxin Pang, Weimin Zhao, Xueqiang Lin
Summary: The stress corrosion behavior of X65 steel in water-saturated supercritical CO2 streams with various impurities was studied. The localized corrosion, mainly depending on impurity type, was significantly accelerated by stress. Oxygen had little effect on the SCC susceptibility of X65 steel, while sulfur dioxide and nitrogen dioxide greatly increased it due to their strong corrosion effects.
Article
Materials Science, Multidisciplinary
Kexi Liao, Jihui Leng, Y. Frank Cheng, Qing Zou, Tengjiao He, Lujie Chen, Min Qin, Xin Liu, Shuai Zhao
Summary: Multi-component thermal fluid flooding is a mature technology for heavy oil recovery, but it can lead to corrosion in gathering pipelines due to the associated gas containing corrosive impurities. This study investigates the effects of different factors on steel corrosion and establishes an empirical model for predicting corrosion rate.
MATERIALS CHEMISTRY AND PHYSICS
(2023)
Article
Engineering, Environmental
Pengbo Hu, Qiyu Weng, Duanle Li, Tao Lv, Shujuan Wang, Yuqun Zhuo
Summary: This study theoretically investigated the effects of flue gas constituents on As2O3 adsorption on γ-Al2O3 surface using DFT, finding that O2 converts most physisorption structures to chemisorption structures and the differences in stable adsorption structures of O2, H2O, SO2, and CO2 are the main factors affecting the positions and quantities of As2O3 physisorption structures. This research provides valuable information for enhancing the capture capacities of γ-Al2O3 in actual flue gas environments.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Engineering, Chemical
Pengbo Hu, Shujuan Wang, Yuqun Zhuo
Summary: This study investigates the effects of alkaline metal promoters on the adsorption properties of MgO for CO2, and finds that alkaline metals can counteract the negative effects of SO2/O2/H2O and enhance the average adsorption energy of CO2. The research results have important practical applications.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Kaiyang Li, Yimin Zeng
Summary: The effects of impurities H2O and O-2 in transported s-CO2 on the corrosion modes and kinetics of pipeline steels were investigated. Pressure is a key factor affecting the solubility of H2O in s-CO2 and corrosion extent, and a threshold pressure above which corrosion rate remarkably increases with pressure was identified. In-situ electrochemical noise (EN) technique revealed that corrosion in s-CO2 with H2O and O-2 is dominated by gas chemical reactions rather than electrochemical reactions.
Article
Chemistry, Multidisciplinary
Xiangdong Kong, Cheng Wang, Zifan Xu, Yongzhi Zhong, Yan Liu, Lang Qin, Jie Zeng, Zhigang Geng
Summary: The diffusion of H2O was modulated by controlling the thickness of the carbon black layer, which effectively regulated the product distribution during CO2 electroreduction. A volcano-type relationship between the thickness of the carbon black layer and the faradaic efficiency for multicarbon products was observed. The faradaic efficiency for C2+ products reached 63.2% on the Cu gas diffusion electrode coated with a 6.6 μm thick carbon black layer at an applied total current density of 800 mA cm(-2), which was 2.8 times higher than that on the Cu gas diffusion electrode without a carbon black layer (16.8%).
Article
Materials Science, Multidisciplinary
Edoardo Basilico, Sabrina Marcelin, Remy Mingant, Jean Kittel, Marion Fregonese, Richard Barker, Joshua Owen, Anne Neville, Francois Ropital
Summary: Water containing CO2 can form a protective pseudo-passive corrosion product layer on carbon steel, but oxygen contamination can significantly alter the corrosion behavior.
Article
Thermodynamics
Xiaoyu Zhang, Shujun Zhu, Jianguo Zhu, Yuhua Liu, Jiahang Zhang, Jicheng Hui, Hongliang Ding, Xiaoyang Cao, Qinggang Lyu
Summary: In this study, anthracite was preheated using a circulating fluidized bed under different atmospheres, and the preheating and combustion characteristics were investigated. The preheated char showed improved structural characteristics, such as increased BET surface area and small aromatic rings, under the O2/CO2 and O2/CO2/H2O atmospheres compared to the O2/N2 atmosphere, particularly when the oxygen concentration was 31%. HCN was found to be the main NOx precursor during preheating under different atmospheres. Additionally, a comprehensive evaluation method for ignition and stable combustion characteristics of preheated fuel was proposed, considering the minimum thermal power required for preheated char combustion and the combustion heat of preheated coal gas as the main factors. The highest combustion efficiency of anthracite was 98.85% under the O2/N2 atmosphere (with oxygen concentrations of 31.0%, 36.0%, and 35.0% for primary, secondary, and tertiary gases), and the lowest NO emission in the tail flue gas was 24.24 mg/MJ under air atmosphere.
Article
Materials Science, Multidisciplinary
G. Y. Zhu, Y. Y. Li, B. S. Hou, Q. H. Zhang, G. A. Zhang
Summary: The study found that 13Cr stainless steel exhibits self-passivation in high pressure CO2/O-2 environment, but the dissolution of steel inside crevice is accelerated under stress. Applied stress reduces the induction stage of crevice corrosion, resulting in a larger galvanic current and promoting the development of crevice corrosion. Additionally, adding 0.1 MPa O-2 helps form a more stable passive film but leads to a greater galvanic effect.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
Kaiyang Li, Yimin Zeng, Jing-Li Luo
Summary: The study found that adding 100 ppm H2O significantly increased oxidation reactions in supercritical CO2, while the presence of O2 led to the opposite tendency. Alloy 740 showed better resistance to carburization and exhibited good corrosion resistance in the supercritical CO2 environment when compared to SS310.
Article
Materials Science, Multidisciplinary
Reyixiati Repukaiti, Lucas Teeter, Margaret Ziomek-Moroz, Omer N. Dogan, Richard P. Oleksak, Randal B. Thomas, John Baltrus, Douglas R. Kauffman, Julie D. Tucker
Summary: Through immersion experiments in aqueous environments, it was found that in low-temperature components of direct supercritical CO2 power cycles, specimens exposed at 100 degrees Celsius had the highest corrosion rate, followed by those exposed at 50 degrees Celsius, while specimens exposed at the highest temperature exhibited the lowest corrosion rate. The specimen surfaces formed an outer noncontinuous, nonprotective Fe-rich oxide layer and a well-adhered inner oxide layer containing both Fe and Cr, with the inner oxide layer transitioning from amorphous to crystalline with increasing temperature.
Article
Energy & Fuels
Xiaoqian Liu, Yinhe Liu, Qiang Lv, Bo Wang, Yandi Zhang, Yao Zhou
Summary: Oxy-fuel combustion is a promising carbon capture technology that can alleviate the slagging and fouling issues in high alkali Zhundong coal-fired boilers. However, the existing kinetic models often neglect the gasification reactions by CO2 and H2O, leading to insufficient prediction accuracy. This study established a co-gasification reaction model and proposed a novel method considering the chemical cooling effect to calculate the char-O-2 reaction rate under high temperature and complex atmosphere. A comprehensive high temperature gasification reaction model was successfully developed.
