基于感应炉正交实验的钢包脱磷工艺研究

为降低提钒后半钢高P含量,减小转炉生产负荷,提出半钢钢包脱磷工艺研究,建立"提钒-脱磷-脱碳"三联冶炼工艺。基于感应炉脱磷四因素三水平正交实验,得出影响脱磷率的因素主次顺序为:供氧流量渣量Ca O质量分数供氧时间,并给出模拟实验下的最优半钢脱磷渣配比与供氧模式,为工业试验提供理论依据。根据感应炉实验结果分析,进行半钢脱磷工业试验,结果表明:大供氧流量与高半钢入炉温度可提高炉渣的脱磷能力。随脱磷渣碱度上升,脱磷率呈先上升后下降的趋势,拐点发生在碱度为3.26时,试验中脱碳量与脱磷量平均比例3.17:1。     

110t转炉脱磷工艺优化

结合某炼钢厂110 t转炉的实际生产情况,研究了转炉操作工艺对脱磷的影响。从转炉吹炼的角度探讨了供氧制度、底吹制度和加料制度对脱磷的影响以及这些影响因素之间的相互作用。建议采用"高-低-高-低"的氧枪操作制度,适当增大吹炼前期和后期的底吹强度,造渣料分批加入,从而达到快速化渣脱磷,降低渣中TFe,提高钢水收得率的冶炼效果。通过操作制度综合优化,可以达到稳定、有效地脱磷,满足现阶段所炼钢种的成分要求。     

50t氧气顶吹转炉脱磷影响因素分析

介绍了某钢厂生产现状及工艺流程,简要阐述转炉炼钢脱磷理论,并对50t氧气顶吹实际生产过程数据进行进行采集,所采集数据主要包括入炉铁水成分、入炉铁水温度、转炉终点成分、终点温度、终渣碱度、终渣成分等。对所采集的数据进行统计分析,研究转炉脱磷的影响因素,为提高转炉脱磷效率,降低炼钢成本提供指导。     

转炉不同冶炼工艺发展与应用

梳理了单渣法、双渣法和双联转炉冶炼工艺的特点，比较了不同工艺的优缺点。单渣法冶炼周期段、工艺简单，但是脱磷效果一般；双渣法可以防止喷溅、脱磷效果好，有利于提高前期脱磷、脱硫以及转炉热效率，保护炉衬降低石灰消耗。但是双渣法倒渣困难，前期温度控制不好，可能会带铁出炉，降低金属收得率。双联工艺脱磷效果好，渣铁分离更容易，降低石灰消耗，在控制合理时，可以缩短整个的生产周期。但是目前国内钢铁企业尚未完全发挥出双联工艺的优势，石灰消耗、脱磷水平以及冶炼周期还存在进一步优化的空间。     

干料打结工频炉衬的材料与施工

一、概述现代大型铸造车间为满足铸件生产质量的要求和适应大批量生产的需要,已较普遍采用冲天炉—工频炉的双重熔炼工艺。应用工频炉可以贮存铁水、均衡生产、均匀不同炉次的冲天炉铁水成份、提高浇注铁水的温度,特别是在连续生产的浇注线和薄壁体的生产中,更显其良好的作用。     

100t半钢钢包复吹脱磷工艺研究

通过水模拟实验,对100 t半钢钢包流动特性及冲击凹坑变化规律进行了研究,并根据结果进行工业试验,确定了半钢钢包的操作工艺。水模研究表明:当氧枪枪位600 mm、侧吹角度43°、顶吹流量3000(标准)m3/h及底吹流量100 L/min时,缩短了混匀时间,对熔池搅拌效果最好,以此确定工业试验方案。工业试验结果表明在半钢钢包复吹脱磷工艺下,脱磷渣化渣效果好,泡沫化程度高,渣中的Fe O含量适中,炉渣具有很强的脱磷能力,脱磷效果好,脱磷率达到65%;半钢包内脱碳及脱磷同时进行,且脱碳量与脱磷量平均比例为2.85。     

120t转炉双联炼钢工艺脱磷试验研究

对脱磷转炉脱磷机理和造渣过程进行了分析,研究了半钢温度、(C)对终点(P)的影响,炉渣碱度、(FeO)对炉渣(P2O5)的影响。结果表明:终点温度超过1 360℃,半钢(P)增加,脱磷效果变差;半钢(C)在3.0～3.4%之间时,半钢平均(P)较低,在0.020%以内;炉渣(FeO)低于30%时,渣中(P2O5)含量随炉渣(FeO)增加而增加,当炉渣(FeO)继续增加时,渣中(P2O5)变化不大;当炉渣碱度大于1.5时,炉渣碱度增加对渣中(P2O5)影响不大,主要是低温制约了化渣效果。     

感应炉石英砂炉衬(Ⅲ)

感应炉服役期是指从烘炉的第一炉起到拆炉为止出铁水量的总和(t)，电弧炉、中频炉与高频炉大都采用出完铁水再装料，可从熔炼了多少炉次(通常叫作炉龄)来计算服役期；工频炉都采用剩留铁水装入炉料熔炼，当每次剩留铁水不相同时，其服役期只能以出铁水量的总和来计算。     

转炉石灰石双渣低成本工艺研究与实践

通过对转炉炼钢前期脱磷和石灰石造渣的理论分析,开发了一种降低成本的转炉炼钢工艺。在脱磷期用石灰石代替石灰作为造渣剂,脱磷结束后,倒除部分富磷渣,然后进行小渣量脱碳,吹炼终点保留脱碳渣用于下一炉脱磷。研究结果表明：与常规冶炼工艺相比,采用石灰石双渣工艺,转炉的石灰石消耗45 kg/t,轻烧白云石消耗20 kg/t,渣料成本10.5元/t,同比石灰双渣法吨钢成本降低9.6元。吹炼终点钢水w（P）控制在0.008%～0.018%,平均为0.011%,满足冶炼工艺的要求。     

基于计算机网络技术的脱磷工业炉过程控制系统设计

基于计算机网络技术设计了脱磷工业炉过程控制技术,并对其实践应用效果进行了分析。结果发现,控制系统运行效果较好,L1级与L2级自动化控制系统不仅可显著延长炉使用寿命,减少耐材整体消耗,还可切实合理利用生产工艺中的不平衡,节约故障处理时间;静态模型与动态模型炼钢运行稳定性与可靠性较高,一次性拉碳与终点温度命中率实现了显著提升,减少了炉渣内的铁含量,脱磷效果良好,且集成了炼钢时的快速测量、智能计算、快速动作。     

太阳能制氢研究现状及展望

综述了国内外制氢研究现状。对常用的太阳能制氢方法：直接热分解法、热化学循环法、光电化学分解法(PEC)以及光催化法进行了分析，指出了各种方法的研究难点和重点。并结合我国的现状提出目前我国应该把光电化学分解法和2步热化学循环法作为研究的重点。     

Evaluation of hydrogen production methods using the Analytic Hierarchy Process

In this paper, seven common hydrogen production processes are evaluated using the Analytic Hierarchy Process (AHP) in respect to five criteria. The processes to be evaluated are steam methane reforming (SMR), partial oxidation of hydrocarbons (POX), coal gasification (CG), biomass gasification (BG), the combination of photovoltaics and electrolysis (PV–EL), the combination of wind power and electrolysis (W–EL) and the combination of hydropower and electrolysis (H–EL). The selected criteria that were used in the evaluation, for each of the seven hydrogen production processes are CO₂ emissions, operation and maintenance costs, capital cost, feedstock cost and hydrogen production cost. According to the evaluation, the processes that combine renewable energy sources with electrolysis (PV–EL, W–EL and H–EL) rank higher in classification than conventional processes (SMR, POX, CG and BG).     

Hydrogen production by biological processes: a survey of literature

Hydrogen is the fuel of the future mainly due to its high conversion efficiency, recyclability and nonpolluting nature. Biological hydrogen production processes are found to be more environment friendly and less energy intensive as compared to thermochemical and electrochemical processes. They are mostly controlled by either photosynthetic or fermentative organisms. Till today, more emphasis has been given on the former processes. Nitrogenase and hydrogenase play very important role. Genetic manipulation of cyanobacteria (hydrogenase negative gene) improves the hydrogen generation. The paper presents a survey of biological hydrogen production processes. The microorganisms and biochemical pathways involved in hydrogen generation processes are presented in some detail. Several developmental works are discussed. Immobilized system is found suitable for the continuous hydrogen production. About 28% of energy can be recovered in the form of hydrogen using sucrose as substrate. Fermentative hydrogen production processes have some edge over the other biological processes.     

Hydrogen,nuclear energy,and the advanced high-temperature reactor

Nuclear energy has been proposed as an energy source to produce hydrogen (H₂) from water. An examination of systems issues in this paper indicates that the infrastructure of H₂ consumption is now compatible with the production of H₂ by nuclear reactors. Alternative H₂ production processes were examined to define the requirements such processes would impose on the nuclear reactor. These requirements include supplying heat at a near-constant high temperature, providing a low-pressure interface with the H₂ production processes, isolating the nuclear plant from the chemical plant, and avoiding tritium contamination of the H₂ product. A reactor concept—the advanced high-temperature reactor—was developed to match these requirements for H₂ production.     

Application of the exergy method to environmental impact estimation: The ammonium nitrate production as a case study

The exergy method is used to compare different production processes and various methods for emission abatement with respect to their overall environmental impact. Some ammonium nitrate production processes are studied as examples, because the pollutants (ammonia and ammonium nitrate), emitted from these processes into the air and/or into the water, are really a feedstock and a product from the production process. Therefore, the essential result of the waste flows treatment is the recycling of the pollutants (ammonia and ammonium nitrate) back into the production process, decreasing simultaneously the exergy input and cumulative exergy consumption     

Comparing biological and thermochemical processing of sugarcane bagasse: An energy balance perspective

The technical performance of lignocellulosic enzymatic hydrolysis and fermentation versus pyrolysis processes for sugarcane bagasse was evaluated, based on currently available technology. Process models were developed for bioethanol production from sugarcane bagasse using three different pretreatment methods, i.e. dilute acid, liquid hot water and steam explosion, at various solid concentrations. Two pyrolysis processes, namely fast pyrolysis and vacuum pyrolysis, were considered as alternatives to biological processing for the production of biofuels from sugarcane bagasse. For bioethanol production, a minimum of 30% solids in the pretreatment reactor was required to render the process energy self-sufficient, which led to a total process energy demand equivalent to roughly 40% of the feedstock higher heating value. Both vacuum pyrolysis and fast pyrolysis could be operated as energy self-sufficient if 45% of the produced char from fast pyrolysis is used to fuel the process. No char energy is required to fuel the vacuum pyrolysis process due to lower process energy demands (17% compared to 28% of the feedstock higher heating value). The process models indicated that effective process heat integration can result in a 10-15% increase in all process energy efficiencies. Process thermal efficiencies between 52 and 56% were obtained for bioethanol production at pretreatment solids at 30% and 50%, respectively, while the efficiencies were 70% for both pyrolysis processes. The liquid fuel energy efficiency of the best bioethanol process is 41%, while that of crude bio-oil production before upgrading is 67% and 56% via fast and vacuum pyrolysis, respectively. Efficiencies for pyrolysis processes are expected to decrease by up to 15% should upgrade to a transportation fuel of equivalent quality to bioethanol be taken into consideration.     

Treatment of olive mill wastewater by different physicochemical methods and utilization of their liquid effluents for biological hydrogen production

In this study various two-stage processes were investigated for biological hydrogen production from olive mill wastewater (OMW) by Rhodobacter sphaeroides O.U.001. Two-stage processes consist of physicochemical pretreatment of OMW followed by photofermentation for hydrogen production. Explored pretreatment methods were chemical oxidation with ozone and Fenton's reagent, photodegradation by UV radiation, and adsorption with clay or zeolite. Among these different two-stage processes, strong chemical oxidants like ozone and Fenton's reagent have the highest color removal (90%). However, their effluents were observed to be unsuitable for both hydrogen production and bacterial growth. On the other hand, clay treatment method was selected as the optimum process that allows fast and low-cost treatment as well as its effluent found to have the highest hydrogen production potential (31.5 m³ m^?3). Spent-clay regeneration was also investigated on the grounds that solid waste minimization is important for the overall efficiency of this process.     

Biohydrogen production from wastewater-based microalgae: Progresses and challenges

Microalgae originating from wastewater has been exhibiting particularly promising results in terms of biohydrogen production and wastewater treatment. This paper aims to review the factors affecting production, pretreatment techniques to improve synthesis, advanced technologies utilized for enhancing biohydrogen production, and techno-economic feasibility evaluation of the processes at a commercial scale. Microalgae possess metabolic components to synthesize biohydrogen using photobiological and fermentative processes but must undergo pretreatment for efficient biohydrogen production. The efficiency of these processes is influenced by factors such as the microalgae species, light intensity, cell density, pH, temperature, substrates, and the type of bioreactors. Moreover, many limitations, such as oxygen sensitivity, altered thylakoid constitution, low photon conversion efficiency, light capture disruption, and the evolution of harmful by-products hinder the sustainability of biohydrogen production processes. High operational and maintenance costs serve as the major bottleneck in the scaling up of the process as an industrial technology. Therefore, future research needs to be directed towards increasing optimization of the processes by reducing energy and resource demand, recycling metabolic wastes and process components, genetically engineered microalgae to adopt more efficient routes, and conducting pilot studies for commercialization.     

Investigation of hydrogen production methods in accordance with green chemistry principles

Hydrogen, as a clean fuel of future, is always counted environmentalist. However, production of hydrogen is not always green. Therefore, a need appeared to re-design the processes for terminating non-renewable resource dependency, minimizing wastes, increasing efficiency, and becoming greener. A systematic approach, Green Chemistry, which is based on 12 principles can be an instructive. This paper aimed to investigate the hydrogen production methods in accordance with green chemistry principles. Each method was evaluated for 12 principles to decide if they could meet the requirements or not. Hydrogen production methods investigated were classified under 4 groups according to the energy sources: electrical, thermal, hybrid and biological. After an overview of the main hydrogen production processes, we show that water electrolysis among electrical methods, biomass gasification as being CO₂ neutral among thermal methods, photo-electrochemical production among hybrid methods and bio-photolysis and photo-fermentation among biological methods makes hydrogen production “green”.     

Coupling of thermochemical hydrogen production processes with an HTGR

The rates of hydrogen production by the two thermochemical processes we proposed were estimated when they were coupled with an HTGR. Also, the sensitivities of the hydrogen production rate to the highest reaction temperature and to the highest secondary helium temperature were investigated for each process. On those temperatures, the hydrogen production rate is strongly dependent, because of the relatively large requirement of the process heat at the high temperature region.