Industrial Trials Research Articles

Investigation on the desulphurisation process by powder injection during RH refining process of non-oriented silicon steel

In the present study, the desulphurisation process by powder injection during RH (Ruhrstahl-Heraeus) refining process was studied by establishing a kinetic model. The predicted results by the model were compared with experimental data obtained from industrial trials to verify its accuracy. The effects of the desulphuriser particle diameter, desulphuriser composition and powder injection rate on the desulphurisation process were analysed and discussed. Results show that the desulphuriser particle diameter and powder injection rate considerably affected the desulphurisation process. By decreasing the desulphuriser particle diameter and increasing the powder injection rate, the reaction area between desulphuriser particles and liquid steel considerably increased. Therefore, the desulphurisation rate and ratio increased. When the desulphuriser particle diameter decreased from 3.0 to 0.1 mm, the desulphurisation ratio increased from 44.6% to 88.4%. The ratio increased from 32.8% to 62.2% for 3.0 mm desulphuriser particles when the powder injection rate increased from 100 to 250 kg min−1. Furthermore, an increase in the desulphuriser basicity and CaO/Al2O3 ratio improved the sulphur capacity and accelerated the desulphurisation process. The desulphuriser used herein had a low sulphur partition ratio, and thus it yielded a lower desulphurisation ratio than the CaO-SiO2-Al2O3 desulphuriser.

Influence of HPGR operating parameters on the edge and centre product – an industrial trial

ABSTRACT High pressure grinding rolls has been widely used in mineral industries as energy-efficient equipment. During the working life of an HPGR mill, the rolls’ surface wears out, and a concave wear profile (maximum wear in the middle) occurs on the rolls. As a result, a difference between HPGR discharge particle size from the middle and edges is also expected that has yet to be quantified. On the other hand, many operational variables affect the HPGR performance; however, there is an interaction between the operational variables and worn rolls. This work studied the effect of operational variables such as hydraulic pressure, rolls’ rotation speed, level of material in the hopper, and operational gap on the HPGR performance on an industrial scale. In addition, the particle size of HPGR discharge from the middle and edges of the rolls is also investigated. Results indicated that HPGR discharge from the middle of the rolls is always finer than discharge from the edges, while the difference between the discharge size from the middle and edges depended on the other variables. Furthermore, it was concluded that deeper material levels in the hopper and lower rotation speed of the rolls resulted in a finer HPGR discharge. This finding is crucial in optimising the HPGR performance and modifying the design of HPGRs to regulate the distribution of material on the rolls.

Progress Toward Biocarbon Utilization in Electric Arc Furnace Steelmaking: Current Status and Future Prospects

AbstractSteel is an essential material in modern infrastructure and industry, but its production is associated with significant carbon dioxide emissions. Biocarbon utilization in electric arc furnace (EAF) steelmaking represents a promising pathway toward reducing the carbon footprint of steel production. This review draws new perspectives on the current state of biocarbon utilization in EAF steelmaking by collectively examining the literature from multiple scales of testing, from laboratory experiments to industrial trials. The scientific insights from each scale are defined and the results are collectively pooled to give a comprehensive understanding of biocarbon’s performance for EAF applications. Several recent progressions are identified along with critical limitations, such as biocarbon’s high reactivity or low density. However, solution pathways like agglomeration are established from the thorough understanding developed by this study. These insights aim to enhance the progression of biocarbon utilization in the EAF process, ultimately facilitating the development of more efficient and sustainable steelmaking. The proposed areas for future research, such as optimizing key biocarbon properties or improved injection systems, are expected to have significant impact on the next phase of biocarbon adoption. Graphical Abstract

Patient enrollment to industry- versus NIH-sponsored cancer clinical trials.

46 Background: The conduct of cancer clinical research in the U.S. is supported by both private and public sponsors. Industry aims to obtain new drug approvals. Federally-sponsored trials examine a broad set of research questions that are not typically addressed by industry; these trials, which are also more commonly conducted in diverse populations, were recently shown to have contributed to gains of 14 million life-years for patients with cancer. Despite the different mandates, the proportion of patients who participate in industry vs. federally-sponsored cancer studies is unknown. Methods: We evaluated trial enrollment patterns from 2008-2022 using ClinicalTrials.gov data. The ratio of enrollments attributable to industry versus federal sponsors was estimated. A large set of 990 estimates based on different combinations of study characteristics were generated. Point estimates were determined as the mean of combinations and confidence limits by the interquartile range (IQR). Five-year intervals were examined to smooth annual variation. Results: N=26,080 studies were examined. The estimated enrollment ratio from 2018-2022 for all industry vs. federally-sponsored trials was 8.1 (IQR:6.2-9.9). For adult trials, the ratio increased from 4.8 (IQR:4.4-5.3) during 2008-2012 to 9.6 (IQR:7.4-11.8) during 2018-2022; for trials in children, the ratio increased from 0.7 (IQR:0.6-0.7) to 2.3 (IQR:1.8-2.7). For adult trials, annual enrollment attributable to industry sponsorship increased from 54,127 in 2008-2012 to 113,527 for 2018-2022. In contrast, annual enrollment counts for federally-sponsored trials were flat over the entire study period, including 11,282/year for 2008-2012 and 11,798/year in 2018-2022, even as incident cancer cases in the U.S. increased 18% from 1.53 million in 2010 to 1.81 million in 2020. Conclusions: In the U.S., there is a growing reliance on industry to conduct cancer clinical research. Underinvestment in federally-sponsored research comes at a cost for both patients and researchers, with lost opportunities for scientific, clinical, and population advances.

Industrial Trials on the Cleanliness Improvement, Microstructure Refinement and Performance Enhancement of Rare‐Earth‐Treated 75Cr1 Steel

Industrial Trials on the Cleanliness Improvement, Microstructure Refinement and Performance Enhancement of Rare‐Earth‐Treated 75Cr1 Steel

Innovative Adsorbents for Pollutant Removal: Exploring the Latest Research and Applications.

The growing presence of diverse pollutants, including heavy metals, organic compounds, pharmaceuticals, and emerging contaminants, poses significant environmental and health risks. Traditional methods for pollutant removal often face limitations in efficiency, selectivity, and sustainability. This review provides a comprehensive analysis of recent advancements in innovative adsorbents designed to address these challenges. It explores a wide array of non-conventional adsorbent materials, such as nanocellulose, metal-organic frameworks (MOFs), graphene-based composites, and biochar, emphasizing their sources, structural characteristics, and unique adsorption mechanisms. The review discusses adsorption processes, including the basic principles, kinetics, isotherms, and the factors influencing adsorption efficiency. It highlights the superior performance of these materials in removing specific pollutants across various environmental settings. The practical applications of these adsorbents are further explored through case studies in industrial settings, pilot studies, and field trials, showcasing their real-world effectiveness. Additionally, the review critically examines the economic considerations, technical challenges, and environmental impacts associated with these adsorbents, offering a balanced perspective on their viability and sustainability. The conclusion emphasizes future research directions, focusing on the development of scalable production methods, enhanced material stability, and sustainable regeneration techniques. This comprehensive assessment underscores the transformative potential of innovative adsorbents in pollutant remediation and their critical role in advancing environmental protection.

Study on Safety Tunneling Technology of Secondary Outburst Elimination by CO2 Gas Fracturing in High-Outburst Coal Seam

The No. 3 coal seam in the Yuxi Coal Mine has a measured maximum gas content of 25.59 m3/t, along with a maximum gas pressure of 2.9 MPa, indicating its high risk to gas and outbursts. To mitigate outburst risks of the coal seam, the 1301 working face has been implemented with gas pre-drainage measures by grid boreholes from underlying roadways. After one year of extraction, it was confirmed that the gas content at all 33 test sites was below 8 m3/t, meeting the outburst prevention standards. However, during subsequent coal tunnel excavation, the gas desorption index K1 value frequently exceeded the standard, resulting in numerous occurrences of abnormal gas emission or small-scale outbursts. To tackle the challenges associated with safe excavation following the first-round regional outburst prevention measures, a research and industrial trial of CO2 gas fracturing (CO2-Frac) technology for secondary outburst prevention and rapid excavation was completed. The results show that the dual-hole and high-pressure (185 MPa) CO2-Frac considerably contributes to outburst prevention. K1 exceedances per hundred meters of tunnel excavations were from an average of 2.54 without CO2-Frac to an average of 0.28 after the new technology was implemented, leading to an eight-fold reduction. Additionally, the monthly excavation footage increased from an average of 81.64 m without CO2-Frac to an average of 162.42 m with CO2-Frac, resulting in a two-fold improvement. The dual-hole and high-pressure CO2-Frac is an advanced technology for safe and efficient excavation for secondary outburst elimination in highly outburst-prone coal seams in the Yuxi Coal Mine, with potential for widespread application in similar coal seam conditions.

Effects of delivery tube configuration regarding the gas atomization for preparing Fe-based amorphous powders: Numerical and experimental investigation

The volume of fluid (VOF) model and the discrete phase model (DPM) were adopted for primary and secondary atomization processes, respectively. The effects of the inlet-limited delivery tube geometry on the flow field, melt breakup and particle cooling were then investigated. The results show that under the delivery tube extrusion length of 5 mm, the suction effect and the breakup efficiency can be improved, and the risk of freeze-off can be inhibited. With the decrease of the delivery tube diameter from 2.5 to 1.5 mm, the calculated median diameter is decreased by more than half and the average cooling rate is more than doubled. The industrial trial results under different delivery tube diameters match the simulation results, and the stable casting of melt with low flow rate can be realized by adopting the inlet-limited delivery tube. When the delivery tube diameter is 1.5 mm, the amorphous powder has a median diameter of 38.9 μm and optimal soft magnetic properties with saturation magnetization of 135.0 emu·g−1 and coercivity of 0.26 Oe.

Realization of Bio-Coal Injection into the Blast Furnace

The steel industry accounts, according to the International Energy Agency, for ~6.7% of global CO2 emissions, and the major portion of its contribution is from steelmaking via the blast furnace (BF) route. In the short term, a significant reduction in fossil CO2 emissions can be achieved through the introduction of bio-coal into the BF as part of cold bonded briquettes, by injection, or as part of coke. The use of bio-coal-containing residue briquettes was previously demonstrated in industrial trials in Sweden, whereas bio-coal injection was only tested on a pilot scale or in one-tuyere tests. Therefore, industrial trials replacing part of the pulverized coal (PC) were conducted. It was concluded that the grinding, conveying, and injection of up to 10% of charcoal (CC) with PC can be safely achieved without negative impacts on PC injection plant or BF operational conditions and without losses of CC with the dust. From a process point of view, higher addition is possible, but it must be verified that grinding and conveying is feasible. Through an experimentally validated computational fluid flow model, it was shown that a high moisture content and the presence of oversized particles delay devolatilization and ignition, lowering the combustion efficiency. By using CC with similar heating value to PC, compositional variations in the injected blend are not critical.

Investigation of cellulosic fines removal in dissolving pulp production with small-holed screen plates

This study investigates the influence of hole diameter and hole spacing on the fractionation performance using an industrial scale pressure screen. The objective is to increase the quality of the long fiber fraction during dissolving pulp production by separating cellulosic fines from unbleached softwood sulfite pulp containing 8% (w/w) primary fines (fibrous particles shorter than 0.200 mm fiber length). Different screen basket designs were applied, using the same hole spacing while varying hole diameter, and vice versa. This allowed a comparison of the separate influence of hole diameter and hole spacing on the separation efficiency. Production parameters of screening devices are always a compromise between separation efficiency, runnability/plugging, and throughput. High aperture velocity, high feed consistency and low reject rate were identified as the crucial operating parameters for high cellulosic fines removal efficiency, which turned out to be positive in terms of throughput. Considering the different hole diameters, the industrial trials showed that smaller holes yielded better fractionation results. Whereas reduced hole spacing resulted in a denser fiber network on the screen, reducing the amount of fines and short fibers passing, thereby leading to worse fractionation results. By choosing suitable screening conditions, we found that the weight-weighted fines content was reduced more than 50 percent using a one stage fiber fractionation screen set up under industrial conditions. The lowered fines content in the long fiber fraction is expected to allow a reduced purification effort and a lower chemical demand in the subsequent processes of dissolving pulp production. By reducing the fines fraction, consisting of short fibers, fiber fines, as well as mainly short-chain alkali-soluble carbohydrates (hemicelluloses), improvements in process efficiency and dissolving pulp quality can be achieved.

Innovative approaches for vaccine trials as a key component of pandemic preparedness - a white paper.

WHO postulates the application of adaptive design features in the global clinical trial ecosystem. However, the adaptive platform trial (APT) methodology has not been widely adopted in clinical research on vaccines. The VACCELERATE Consortium organized a two-day workshop to discuss the applicability of APT methodology in vaccine trials under non-pandemic as well as pandemic conditions. Core aspects of the discussions are summarized in this article. An "ever-warm" APT appears ideally suited to improve efficiency and speed of vaccine research. Continuous learning based on accumulating APT trial data allows for pre-planned adaptations during its course. Given the relative design complexity, alignment of all stakeholders at all stages of an APT is central. Vaccine trial modelling is crucial, both before and in a pandemic emergency. Various inferential paradigms are possible (frequentist, likelihood, or Bayesian). The focus in the interpandemic interval may be on research gaps left by industry trials. For activation in emergency, template Disease X protocols of syndromal design for pathogens yet unknown need to be stockpiled and updated regularly. Governance of a vaccine APT should be fully integrated into supranational pandemic response mechanisms. A broad range of adaptive features can be applied in platform trials on vaccines. Faster knowledge generation comes with increased complexity of trial design. Design complexity should not preclude simple execution at trial sites. Continuously generated evidence represents a return on investment that will garner societal support for sustainable funding. Adaptive design features will naturally find their way into platform trials on vaccines.

Formation Mechanism and Control Strategy of Transverse Corner Cracks in Continuous Casting of 55SiCr Spring Steel

An experimental study is conducted to reveal the formation mechanism of transverse corner cracks by analyzing the metallurgical structure, crack morphology, and hot ductility. The results reveal that the corner temperature of the billet tends to be lower during mold solidification, leading to the formation of grain boundary low‐plasticity ferrite. Additionally, during the straightening process, the corner temperature of the billet falls into the serious low‐temperature brittle zone with temperature lower than 850 °C. These two factors contribute to the formation and propagation of cracks along the grain boundary ferrite under straightening forces. Therefore, after the verification of mold simulation test and industrial trial, the temperature at billet (section size 150 × 150 mm2) corner is improved by increasing the mold chamfer radius from 6 to 12 mm. This adjustment ensures that the straightening temperature at billet corner elevated from 830 to 880 °C, remaining outside the serious low‐temperature brittle zone, and the maximum depth of corner cracks decreases from 741.49 to 344.89 μm.

Optimization of the gas system for gas–water combined atomization technique in FeSiBC amorphous powder production

The gas–water combined atomization is an advanced technology for Fe-based amorphous powder preparation, and its gas/water system parameters have significant impacts on powder properties. In this study, numerical simulations and industrial trials were combined to optimize the gas atomization parameters. The results showed that increasing the atomization pressure promotes the transition of the flow field to the closed wake. Moreover, the median particle size was significantly refined and the cooling rate was improved. Extending the extrusion length facilitated the decrease in suction pressure, while excessively long extrusion lengths led to instability in the atomization process. The decrease in delivery tube diameter enhances droplet breakup and cooling, but increases the risk of clogging. Industrial trials at different atomization pressures showed that low atomization pressure led to the formation of needle-shaped powder, and the FeSiBC amorphous powder prepared at 3.0 MPa exhibited optimal comprehensive properties, with saturation magnetization of 166.1 emu·g−1 and coercivity of 4.5 Oe.

Computed tomography (CT) scanning to visualize eye formation and internal structure in Grevé cheese

The Grevé cheese, a semi-hard Swedish cheese, is well-known for its characteristic flavor and shape of eye formation. The size and distribution of the eyes play a crucial role for the sensory attributes, aesthetic value and quality of the cheese. This article focuses on investigating the feasibility of using computed tomography (CT) scanning as a non-destructive tool to observe early-stage eye formation in Grevé cheese within an industrial trial. It is crucial to achieve a perfect combination of small and big sized eyes, evenly distributed within the cheese wheel, without having cracks/splits for optimal quality. Such variations could be visualized using CT-scanning of cheeses at a young and mature stage by providing high-resolution, three-dimensional CT-scanning images of the cheese's internal structure, without the need for physical dissection. Further, the distribution of eyes, their shape and number, could be visualized and compared for the same cheese scanned at young and mature stages. Thus, the importance of monitoring eye formation through non-destructive techniques is emphasized to ensure consistent product quality.

Qualitative Analysis of Inquiries Received by FDA Regarding Conduct of Clinical Trials during the Covid-19 Public Health Emergency

BackgroundThis report describes the U.S. Food and Drug Administration (FDA) experience in establishing a dedicated mailbox, and in publishing related guidance, to address concerns among interested parties regarding the conduct of clinical trials during the COVID-19 public health emergency (PHE).MethodsSix hundred and thirty-four mailbox inquiries were received from March 2020 through February 2022. Qualitative methods were used to provide a structured description of, and identify common themes among, these inquiries.ResultsMost inquiries came from U.S.-based interested parties, including sponsors, industry trade associations, academic institutions, hospitals, clinics, research sites, trial participants, and individual persons. Approximately one-fifth of questions were related directly to COVID-19 (e.g., proposals for treatment); other inquiries were related to conduct of routine trial-related activities, and concerns were often focused on maintaining compliance with good clinical practice. In March 2020, FDA published a guidance titled Conduct of Clinical Trials of Medical Products During the COVID-19 Public Health Emergency; the document was subsequently revised eight times based in part on issues raised in mailbox inquiries.ConclusionsThe dedicated mailbox enabled expedited communication among invested parties during the COVID-19 PHE; FDA also provided updates of the aforementioned guidance. These efforts supported the continuance of ongoing trials and the initiation of new trials during the PHE in accordance with good clinical practice guidelines, thereby helping to ensure the safety of trial participants while maintaining the quality of trial data. By soliciting and responding to trial-related inquiries and addressing corresponding needs and concerns, FDA improved transparency and communication.

Physical field regulation of magnesium alloy wheel formed by backward extrusion process with multi-stage variable speed

To reduce the tonnage required during the forming process of magnesium (Mg) alloy wheels by backward extrusion (BE) and refine the grains at the wheel bottom, the multi-stage variable (MSV) speed process is proposed based on the characteristics of Mg alloy wheels formed by BE. A numerical model for the BE process of Mg alloy wheels using the Defrom-3D was constructed, and the effects of constant speed and MSV speed processes on the physical fields and DRXed grain size evolution during the forming of Mg alloy wheels were investigated. Lastly, the simulation results were indirectly verified by industrial trial production. The results show that constant speed extrusion has a small effect on the effective stress, but a large effect on the wheel temperature distribution, where the forming speed of the upper rim plays a decisive role in the final temperature distribution of the wheel. MSV speed process is used to regulate the physical field evolution during wheel forming based on the effect of constant speed on the physical field of the wheel. With the high-speed forming of the rim and low-speed forming of the upper wheel rim (9-9-1 mm/s), the temperature and effective stress distribution of the wheel blank are reasonable while reducing the forming tonnage and refining the grains at the wheel bottom.

Development of a model for iron concentrate tonnage with least angle regressions – An industrial trial

ABSTRACT The optimal concentrate assay and weight recovery are among the most important factors in mineral processing plants, particularly iron ore beneficiation plants. The optimal balance between concentrate assay and total recovery is typically determined through chemical analysis and application of the Davis tube test in the laboratory. Consequently, the level of concentrate assay and tonnage is regulated in the plant by (a) sampling and chemical analysis in the lab and (b) application of weighing equipment such as belt scales. Belt scales also have a random error and specified standard deviation in weighing and are not completely reliable. Modifying the assay obscures the variation in concentrate weight. The best subset method can be used to extract the relation between concentrate tonnage and process variables; however, this method is unsuitable due to the variance inflation factor (VIF). In this investigation, to circumvent VIF, simple models using least angle regressions (LARS), Lasso, and LAR are presented utilising 2655 data (for each variable) collected from the Gohar Zamin beneficiation iron ore plant. The highest model’s R-square was 66.51%, and it predicted that if the concentrate assay decreases from 68.41% to 67%, the total concentrate tonnage can increase by 33800–35300 tons per year with a 95% prediction interval for the 2 million-ton capacity plant.

Desulfurization characteristics of slaked lime and regulation optimization of circulating fluidized bed flue gas desulfurization process—A combined experimental and numerical simulation study

Circulating fluidized bed flue gas desulfurization (CFB-FGD) process has been widely applied in recent years. However, high cost caused by the use of high-quality slaked lime and difficult operation due to the complex flow field are two issues which have received great attention. Accordingly, a laboratory-scale fluidized bed reactor was constructed to investigate the effects of physical properties and external conditions on desulfurization performance of slaked lime, and the conclusions were tried out in an industrial-scale CFB-FGD tower. After that, a numerical model of the tower was established based on computational particle fluid dynamics (CPFD) and two-film theory. After comparison and validation with actual operation data, the effects of operating parameters on gas–solid distribution and desulfurization characteristics were investigated. The results of experiments and industrial trials showed that the use of slaked lime with a calcium hydroxide content of approximately 80% and particle size greater than 40 μm could significantly reduce the cost of desulfurizer. Simulation results showed that the flow field in the desulfurization tower was skewed under the influence of circulating ash. We obtained optimal operating conditions of 7.5 kg·s−1 for the atomized water flow, 70 kg·s−1 for circulating ash flow, and 0.56 kg·s−1 for slaked lime flow, with desulfurization efficiency reaching 98.19% and the exit flue gas meeting the ultraclean emission and safety requirements. All parameters selected in the simulation were based on engineering examples and had certain application reference significance.

Fluid Flow, Solidification and Solute Transport in Slab Continuous Casting with Different S-EMS Installation Positions

During continuous slab casting, strand electromagnetic stirring (S-EMS) has a significant effect on improving the slab quality. In the current work, a numerical model based on the practical slab continuous casting machine and coupled electromagnetic field, flow field, solidification, and solute transport was established to investigate and evaluate the effect of the S-EMS installation position with various current intensities on metallurgical behavior. The model was verified by magnetic field measurement, infrared camera, and nail shooting experiments. The results show that moving the S-EMS installation position to the solidification end reduces the stirring effect due to the skin effect and the increasing thickness of the slab shell. A higher installation position is beneficial for improving the equiaxed grain rate, while a lower one is beneficial for reducing carbon segregation. The maximum segregation index and range decrease from 1.26 to 1.2 and from 0.42 to 0.36 with the installation position being decreased from −3 m to −12.8 m, respectively. The industrial trials show that S-EMS installed at 3 m has a significant effect on expanding the equiaxed grain zone and a deteriorating effect on reducing carbon segregation.

Effects of the addition of arch-supplied secondary air on the performance of the Foster Wheeler down-fired boiler: Air/particle flow, combustion and NOx emissions

This study proposes a low NOx combustion method for Foster Wheeler type down-fired boilers. The effectiveness of this technique was validated through laboratory-scale gas-particle two-phase experiments and industrial trials. The flow field characteristics within FW-type boiler furnaces equipped with arch-supplied secondary air injection nozzles were investigated. Furthermore, the application of this technique to a 660 MW subcritical FW-type boiler was examined, focusing on NOx emissions and combustion characteristics. Results demonstrate that optimizing the damper openings for F-layer and arch-supplied secondary air can significantly reduce NOx emissions by over 33 %. Additionally, increasing the mass flow rate of arch-supplied secondary air aids in reducing unburned carbon in fly ash and inducing a downward shift in the flame center within the furnace.