Research on Microwave Heating-Direct Steelmaking in Electric Furnace

Self-fluxing iron ore concentrates containing coal have good microwave Absorbability. With the voluminal heating property of microwave, the concentrates can be reduced uniformly and swiftly. The metallized semi-product can be directly charged into electric furnace for making clean steel. The total consumed energy of overall route is about 20 98 GJ.

Heat Transfer Analysis for Industrial AC Electric Arc Furnace

The heat transfer analysis was performed for an AC electric arc furnace (EAF). Heat losses by conduction, convection and radiation from outer surface, roof, bottom and electrodes of EAF were determined in detail. Some suggestions about decreasing heat losses were presented.

Mathematical model on heat transfer of water-cooling steel-stick bottom electrode of DC electric arc furnace

For predicting and controlling the melted depth of bottomelectrode during the process of steelmaking, the water-cooling steel-stick electrode is taken as an example, to analyze the process ofheat transfer, then 3D mathematical model by control capacity methodis built. At the same time, the measurement on the melted depth ofbottom electrode is conducted which verified the correctness of thebuilt mathematical model. On the base of verification, all kinds ofkey parameters are calculated through the application and a series ofresults are simulated. Finally, the optimum parameters are found andthe service life of bottom electrode is prolonged.

Theory and Practice of Heat Transfer in Electric Arc and Flare Furnaces and Power Plants

The author describes the fundamental laws of physics, the laws of thermal radiation of ionized and non-ionized gas volumes. Based on open laws, a modern theory of heat transfer and methods for calculating heat transfer in electric arc and flare metallurgical furnaces, furnaces of steam boilers, and combustion chambers of gas turbine plants of power plants have been developed. The use of scientific discovery makes it possible to create innovative electric arc steel-smelting furnaces, flare heating furnaces, and combustion chambers in which the consumption of electricity and fuel is reduced, productivity and service life are increased, and the amount of harmful emissions into the environment is reduced.

Fluid Flow Modeling of Arc Plasma and Bath Circulation in DC Electric Arc Furnace

A mathematical model describing the flow field, heat transfer and the electromagnetic phenomenon in a DC electric arc furnace has been developed. First the governing equations in the arc plasma region are solved and the calculated results of heat transfer, current density and shear stresses on the anode surface are used as boundary conditions in a model of molten bath. Then a two-dimensional time-dependent model is used to describe the flow field and electromagnetic phenomenon in the molten bath. Moreover, the effect of bottom electrode diameter on the circulation of molten bath is studied.

Electromagnetism and the Arc Efficiency of Electric Arc Steel Melting Furnaces

Results of analytically studied effect of electromagnetic blowing and the slag height on the arc efficiency are stated. An arc is blown from under an electrode toward the furnace walls under an electromagnetic force, arc radiation on the wall and roof increase and effective output, absorbed by the metal decreases. EAF (electric arc steel melting furnace) with independently powered arcs, eliminating its electromagnetic blowing is proposed. When arcs are powered independently, its efficiency increases significantly, and specific energy consumption decreases.

A Compound Cycle for Power Generation by Utilizing Residual Heat of Flue Gas in Electric Steelmaking Process

Electric furnace short process steelmaking is one of the most important steelmaking methods in the world today, and the waste heat recovery potential of electric furnace flue gas is huge.?The research on the recovery of electric furnace flue gas waste heat is of great significance. In order to make better use of this part of the heat,?in this paper, a compound cycle of nitrogen Brayton cycle as a first-order cycle and toluene transcritical Rankine cycle as a second-order cycle is proposed to recover waste heat from furnace flue gas in steelmaking process for power generation. A mathematical model was established with the net output power as the objective function and the initial expansion pressure, the final expansion pressure, the initial expansion temperature and the initial pressure of the second cycle as the independent variables. The effect of multivariate on the net output power of the waste heat power generation cycle is studied, and then, the optimal parameters of the compound cycle are determined. The results show that under the general electric furnace steelmaking process, the power generation efficiency of this new cycle can be increased by 21.02% compared with the conventional cycle.

工业加热电炉高耗电异常DCS数据主动采集技术研究

工业加热电炉在运行过程中容易出现高耗电现象,且异常用电数据产生的频率较高、数据量较大,使得对异常数据的采集效率降低。为此,提出工业加热电炉高耗电异常分布式控制系统数据主动采集技术研究。利用局部平均值计算工业加热缺失DCS数据,采用拉格朗日插值法对其插补,对插补后的数据标准化处理。构建用电不平衡特征矩阵,采用局部离群因子检测算法,提取出用电异常数据特征集,构建基于长短期记忆网络(long short-term memory,简称LSTM)的分位数回归模型,实现工业电炉异常DCS数据的主动采集。实验结果表明,所提方法有效地提高了采集效率和采集精度,采集平均用时仅为029ms,其准确率-召回率在98%以上。

基于TRNSYS的太阳能-电能互补采暖系统研究

针对我国北方农村地区冬季采暖污染严重、碳排放量大等问题,文章以沈阳市某地区典型农村单体式住宅为研究对象,综合考虑太阳能、电能,提出2套清洁供暖方案。首先对太阳能集热器的集热倾角和面积的选择进行优化,然后选取沈阳市供暖季温度较低的2天,根据天气情况分别作为晴天与阴天典型日,最后利用TRNSYS软件对供暖方案在典型日天气条件下模拟运行。结果表明在典型日天气条件下本研究提出的2种供暖方案均满足环保、室内温度适宜等采暖需求,且太阳能集热器+变频电磁采暖炉供暖方案更为节能。

铸造工厂熔化电炉冷却系统余热回收应用的探讨

随着国家推出的高质量发展理念及“碳达峰、碳中和”政策的实施,通过收集铸造工厂熔化电炉冷却相关的资料及运行参数,结合某项目应用的实际案例,介绍了熔化电炉冷却系统余热回收应用场合,同时对采用的余热回收技术方案进行了经济技术分析,确认本次探讨的电炉冷却水余热回收系统的技术方案具备初投资低、运行费用省,能够有效降低企业的碳排放,具备良好的社会经济效益。该余热回收技术方案的推广应用,是企业降低运行费用、减少碳排放的一个有效途径。

基于辐射能信号的火电厂直热式电炉温度控制方法研究

传统电炉温度控制方法存在控制稳定性较差、响应时间较慢等不足,影响了生产产品的质量,为此提出基于辐射能信号的火电厂直热式电炉温度控制方法研究。首先计算辐射能信号和炉内燃烧率,由此为基础,利用火焰彩色辐射图像处理技术获取的辐射能信息,对辐射能信号展开检测;其次以辐射能信号为中间变量,分析直热式电炉温度变化情况,获取温度变化状态;最后采用基于模糊免疫自适应算法的PID控制器,实现火电厂直热式电炉温度的有效控制。实验结果表明,所提方法在保障电炉温度控制稳定性的前提下,控制能力和抗干扰性能较好,具有较高的温度控制精度和效率。

石墨炉原子吸收法测定土壤中铅、镉的方法

土壤中的重金属污染已成为世界范围内环境保护的重要问题之一。铅和镉是常见的土壤重金属污染物,对人类健康和生态系统造成严重影响。因此,准确测定土壤中的铅和镉含量对于环境监测和土壤污染防治至关重要。本文介绍了一种使用石墨炉原子吸收光谱法测定土壤中铅和镉的方法,铅质量浓度0~600.0μg/L、镉质量浓度0~6.0μg/L范围内有良好的线性关系,相对标准偏差铅、镉分别为3.70%、4.29%,该方法具有高灵敏度、高选择性和较低的检测限,能满足土壤中铅、镉的监测要求。

电弧钢厂烟气余热回收用三段流化床反应器设计

针对间歇式电弧炉炼钢开盖时因高温烟气散发而导致的热量损失现象,设计了一台组合式流化床反应器。热回收工艺为:以熟石灰粉(Ca(OH)_(2))为介质,在夹带流反应器中,吸收高温(>600℃)烟气中的热量,转化生成CaO,再将CaO置于流化床反应器中进行水化反应,重新生成Ca(OH)_(2)并放热和降温,用于加热锅炉凝汽器循环水的热电循环。参与热回收的熟石灰循环利用。针对CaO降温与反应的温度要求,流化床反应器由高温段、反应段及低温段三段组成。过热的CaO粉末由上至下依次通过各层流化床层。设计包括流化床各段传热工艺计算、机械结构设计及附件选型。三段流化床为整体结构,工艺性好,为间歇余热利用设备制造设计提供借鉴和参考。

热电联产锅炉炉水电导率超标分析及处理

避免不合格盐水渗入冷凝水,本文对井矿盐热电联产锅炉水电导率异常的可能来源进行了综合分析,从制定应急预案、加强机组排污、锅炉回水监测及自动采样系统查漏补缺、完善锅炉自动采样系统、做好药品验收及改进化验技术等五个方面采取措施进行应对和治理,从而确保制盐预热器设备完好及运行参数稳定。

改进PID控制算法的电加热炉炉温控制系统研究

在工业生产过程中,温度控制效果关系到产品质量以及安全。因此在钢铁冶炼、石油萃取的生产过程中,选用先进的温控算法的使用是十分必要的。随着工业化进程的加快,电加热方式逐渐取代传统方式成为工业温控的首选。温度控制系统在实际工业过程中的应用非常广泛。电加热炉作为新型、安全的特种工业炉,可以以导热油为热载体,通过热油泵使热载体循环,将热量向热设备传递,是一种高效性的工业温度控制设备。以SXF-4-10电加热炉作为研究对象,分析了传统PID电加热炉炉温控制系统的原理以及温控局限性,最后将蚁群算法以及免疫算法相结合提出改进的温度控制方法并加以仿真实验分析,结果发现改进后的PID控制算法能够提升温控系统的响应速度以及抗干扰性,具有显著的优势。

自适应Fuzzy-Smith-PID控制器在加热炉温度控制中的研究与仿真

以箱式加热炉为研究对象,针对PID控制在温度控制中存在滞后和时变性的缺陷,提出一种带有Smith补偿环节的新型模糊PID控制方案,利用MATLAB实现仿真。由仿真结果可知,相比Smith控制和模糊控制,改进后的系统精度更高,抗干扰性和鲁棒性增强,系统过渡过程较为平稳,整体控制效果理想,具有良好的推广价值。

分子筛脱水装置再生加热系统技术对比分析

目的确定直接式电加热器、盘管式铸铝电加热器、燃气导热油炉、电加热导热油炉4种分子筛再生加热系统的技术和经济适用性,为选择最优的再生加热系统提供技术参考。方法对再生加热系统的设备结构、常见故障、技术要点进行了介绍,从适用工况、安全性能、设备投资、优缺点等方面进行了技术对比分析。结果直接式电加热器的建议热负荷在300 kW以内,同时应配备完善的多维度多点控制保护措施;盘管式铸铝电加热器建议使用在高压、腐蚀性、有毒介质等特殊工况,单台热负荷在200 kW以内;电加热导热油炉系统易于实现小型化、标准化、模块化,建议热负荷为150~400 kW;燃气导热油炉系统在热负荷大、多点用热和双温位用热等工况下建议选用。结论分子筛脱水装置应在设计条件下进行技术经济对比后选择合适的再生加热方式。

粗苯精制管式加热炉改造

以焦炉煤气为燃料气的管式加热炉,在粗苯精制生产中存在着诸多弊端,通过不同加热介质的比选,对管式加热炉进行了改造,有效规避了原管式加热炉在安全、烟气排放以及调控精度等方面的弊端。

基于神经网络算法的电加热过程温度控制

采用单神经元PID与传统PID控制相互结合的方法,探索高效电加热过程智能温度控制系统,并利用Simulink软件对传统PID控制和单神经元PID控制下的加热炉温度控制系统进行了仿真对比实验。结果表明,单神经元PID模型控制下的加热炉温度控制系统能够实时调整控制参数,使得控制参数和温度控制系统较为匹配,可以实现系统在最稳定的状态运行,该系统对干扰的抵抗性更好,鲁棒性更强。而实际试验中,单神经元PID控制下的加热炉温度控制系统在温度响应阶段具有较高的稳定性,同时在稳态阶段也拥有较高的控制精度,但是在初始温升过程中的响应速度较低。

电加热炉变电设备运行质量安全数据追溯方法设计

在电加热炉变电设备运行质量安全数据的反向追溯过程中,由于当前相关流程均缺少电加热炉变电设备运行质量的评价指标体系,导致追溯过程主观性过强,缺少统一追溯方法,因此设计了电加热炉变电设备运行质量安全数据追溯方法设计。通过电加热炉技术采集的虚拟数据结合追溯法,建立电加热炉变电设备运行质量的指标体系。再结合斯皮尔曼等级相关系数和熵权,计算质量追溯指标对应的客观权重,通过理想点法构建电加热炉变电设备运行质量数据反向评估模型,完成电加热炉变电设备运行质量的安全追溯。实验结果表明:这种追溯方法可准确地获取电加热炉变电设备的功能失效率和系统安全风险系数,安全追溯结果精准度高。