REVIEW | doi:10.20944/preprints201812.0153.v1
Subject: Chemistry And Materials Science, Metals, Alloys And Metallurgy Keywords: Carbon dioxide; Injection; Blast Furnace; Converter; Combustion
Online: 12 December 2018 (15:32:35 CET)
A overview on application of CO2 in the ironmaking and steelmaking process is presented. Study on resource utilization of CO2 is significant for the reduction of CO2 emissions and the coping with global warming. The paper introduces the research progress of CO2 utilization in the sintering, Blast Furnace, Converter, secondary refining, Continuous Casting and smelting process of stainless steel in recent years in China. According to the foreign and domestic research and application status, the paper analyzes the feasibility and metallurgical effects of the CO2 utilization in the ferrous metallurgy process. The paper mainly introduces such new techniques as 1) flue gas circulating sintering, 2) blowing CO2 through Blast Furnace tuyere and CO2 as a pulverized coal carrier gas, 3) top and bottom blowing CO2 in the converter, 4) Ladle Furnace and Electric Arc Furnace bottom blowing CO2, 5) CO2 as Continuous Casting shielding gas, 6) CO2 for stainless steel smelting, and 7) CO2 circulation combustion. CO2 has a very wide application prospect in ferrous metallurgy process and the quantity of CO2 utilization is expected to be 100kg per ton of steel. It will effectively facilitate the progress of metallurgical technology and strongly promote the energy conservation of metallurgical industry.
ARTICLE | doi:10.20944/preprints202306.0064.v2
Subject: Engineering, Marine Engineering Keywords: n/a; ship and Ocean Engineering; Marine Structures; Global Stress; Artificial Intelligence; structure health monitoring (SHM)
Online: 8 June 2023 (10:52:36 CEST)
This paper proposes an AI-based approach to overcome the limitations of the SHM system in measuring global stress with limited sensors. Feature elements are selected based on correlation analysis among finite elements and used as stress-measured points. An ANN is used to establish the solution relationship between the feature and correlation elements. The proposed method is applied to the connector structure of an offshore platform, and an optimal ANN is established to optimize accuracy by considering factors like the number of sensors, neural network framework, and convergence criteria. The accuracy of the ANN is verified through a real-scale model test, demonstrating 93.6% accuracy. This technology represents a significant advancement, enhancing the practicality of the structural health monitoring (SHM) system from “point monitoring" to “field monitoring".
ARTICLE | doi:10.20944/preprints202305.2181.v1
Subject: Engineering, Civil Engineering Keywords: debris flow simulation; remote sensing; tree ring; Massflow; northeastern Tibet
Online: 31 May 2023 (07:29:40 CEST)
Rare study on quantitative relationship between energetic impact of debris flows on the intensity and duration of growth disturbances of tree rings was carried out, partly due to lack of feasible approaches and detailed field evidence. In this study, we firstly determine the age of a recent debris flow derived from historic landslide deposits at Qingyang mountain (QYM) on the northeastern Tibet plateau by dendrogeomorphic technique. We acquired the quantitative data of annual widths of tree rings in history and confirmed the influence of debris flow rather than other factors (e.g. climatic event and inset outbreaking) in disturbing the growth of tree rings in a specific year. Using the approach, we determined the age of the debris flow at QYM occurred in 1982, which was speculated to be triggered by high monthly precipitation of July in 1982. Subsequently, based on the boundaries of historic debris flow identified on remote sensing images before and after 1982 and depth-integrated continuum model, we reconstructed the process of 1982-debris flow and obtained the kinematic energy of debris flow impacting on the sampled trees. Based on the study, we observed that two growth disturbance patterns of tree rings influenced by the reconstructed 1982-debris flow were revealed including growth suppression and asymmetric growth. A raw logarithm relationship between duration (i.e. lasting time for the disturbed tree rings to recover the initial width) and intensity of growth disturbances (i.e. growth suppression ratio of disturbed tree rings) was obtained. We concluded that there is a negative exponential relationship between simulated kinematic energy of debris flow impacting on the disturbed trees and time to recover the initial width of corresponding tree rings.