高炉喷吹煤和废塑料混合燃料的可行性研究

分析了高炉喷吹混合燃料的可磨性、黏结指数和胶质层厚度等对高炉冶炼的影响,并对高炉喷吹煤粉、喷吹煤粉与废塑料混合燃料进行了燃烧模拟。结果表明,高炉喷吹煤与废塑料混合燃料在理论上是可行的。     

煤和塑料混熔喷吹技术研究

概述了国外高炉喷吹废塑料技术现状和国内研究进展,提出了煤与废塑料混熔高炉喷吹新工艺.对不同比例的废塑料与煤粉混合,在200 ℃的混熔温度下制成样品进行燃烧特性试验.结果表明:混熔样品具有良好的燃烧性能,开始燃烧温度和激烈燃烧温度都比煤粉低,塑料的存在对煤有提前燃烧作用,废塑料混熔比例在25%时燃烧时间较煤粉短,燃烧速度快;废塑料与煤混熔对高炉喷吹技术,理论上是可行的.     

废塑料入炉喷吹的数值模拟研究

基于高炉喷吹混合燃料的方法,探究废塑料作为燃料在高炉内的作用。以某2536m3高炉为研究对象,将喷入的煤粉及塑料作为粉相,分析混合燃料的水分、灰分、挥发分和固定碳等化学指标,采用高炉高温区热平衡分析法,计算高炉单一喷吹和混合喷吹条件下的焦比,对高炉内喷吹过程进行模拟研究。计算机模拟结果表明,将煤粉与废塑料混合喷吹降低了高炉焦比,提高了煤的利用率。     

高炉喷吹废塑料工艺技术探讨

介绍了国内外高炉喷吹废塑料工艺的研究进展,着重从化学成分、高炉内的反应情况、废塑料的分类回收以及塑料制粒角度说明了废塑料作为高炉喷吹燃料的可行性,并给出适合高炉喷吹废塑料的工艺流程,强调了废塑料与煤粉在风口前管路上混合能促进塑料和煤粉在回旋区更好地燃烧。     

在直吹管和风口内混合喷吹煤粉和废塑料的数值模拟

运用数值模拟方法,对废塑料和煤粉混合喷吹条件下直吹管和风口内的燃烧特性进行了研究。将废塑料与煤粉按不同比例混合,在不同粒径分布下喷吹时,分析了直吹管和风口内的挥发分析出和燃烧的规律。结果表明,随着混合燃料中废塑料比例增加,颗粒粒径减小,混合燃料的燃烧性能提高;从喷吹单一煤粉到喷吹煤粉与废塑料比为5∶5的混合燃料时,直吹管和风口内燃烧率从3.35%提高到36.31%。     

进口喷吹煤的研究与在韶钢高炉的应用

对进口喷吹煤俄罗斯南库巴斯煤进行了性能研究,并对韶钢3 200 m~3高炉喷吹应用情况进行总结。通过试验研究分析,得知进口喷吹煤具有较高的热值、较好的燃烧性能和较弱的爆炸性,可以单煤种喷吹和混合喷吹;进口煤与烟煤混合煤喷吹,有利于提高燃烧性能,同时没有爆炸性。工业试验结果表明,使用进口煤喷吹后,韶钢3 200 m~3高炉炉况稳定顺行,铁产量增加,燃料比降低,吨铁燃料成本降低约3.6元。     

高炉中喷吹废塑料的可行性研究（Ⅱ）——废塑料与煤粉的热特性对比研究

为了研究向高炉中喷吹废塑料的可行性,对几种常见废塑料与高炉喷吹用煤粉在升温过程的热行为进行了对比研究。结果表明：与煤相比,废塑料热值高,从着火到燃烧结束所需时间短,且占整个升温过程耗时比例低。从而表明从热特性角度分析,废塑料适用于高炉喷吹。     

高炉喷吹废塑料与喷吹煤粉比较分析

从工艺流程、原料化处理工艺及在高炉中能量利用三方面对高炉喷吹煤粉和废塑料进行比较分析可以看出,高炉喷吹废塑料和高炉喷吹煤粉一样可以作为高炉辅助喷吹燃料技术,高炉喷吹废塑料不仅为高炉炼铁提供了燃料,更能解决废塑料造成的环境污染问题,是兼顾社会效益、环境效益和生产效益的综合利用技术。     

混合喷吹煤粉和废塑料对高炉炉腹煤气的影响

为了研究混合喷吹时煤粉和废塑料对高炉炉腹煤气的影响,通过计算,得到喷吹不同比例混合的煤粉与废塑料时高炉炉腹煤气量及煤气成分。结果表明:随着混合燃料中废塑料比例增加,炉腹煤气量增加,煤气成分也相应改变;当PE(煤粉与聚乙烯)∶PP(聚丙烯)按5∶5混合时,炉腹煤气中φ(CO+H2)所占比例为47.96%,而单一喷吹煤粉时φ(CO+H2)所占比例为44.44%。     

低变质煤热解提质及其半焦作为高炉喷吹用燃料的特性分析

为降低焦比、优化高炉燃料结构和降低生铁成本,结合高炉喷吹要求,对半焦部分特性进行了分析。结果表明:与既有的两种喷吹煤对比,样品半焦的燃烧性能均介于两种喷吹煤之间,但半焦之间差异明显;工业分析和半焦的表面与攀钢喷吹煤相似,但累积比表面积较大;基本上能满足高炉喷吹燃料要求,但对于部分高灰分和挥发分半焦,应当考虑混合使用或不用。     

Investigation on Co-Combustion Kinetics of Anthracite and Waste Plastics by Thermogravimetric Analysis

 In order to effectively recycle resource for the benefit of the global environment, the utilization of waste plastics as auxiliary injectant for blast furnaces is becoming increasingly important. Combustion kinetics of plastics-coal blends with 0, 10%, 20% and 40% waste plastics (WP) are investigated separately by thermogravimetric analysis (TGA) from ambient temperature to 900 ℃ in air atmosphere. These blends are combusted at the heating rates of 5, 10 and 20 ℃/min. The results indicate that, with the increase of waste plastics content, the combustion processes of blends could be divided into one stage, two stages and three stages. The waste plastics content and heating rates have important effects on the main combustion processes of blends. With the increase of waste plastics content, the ignition temperature and the final combustion temperature of blends tend to decrease, while the combustion reaction becomes fiercer. With the increase of the heating rate, the ignition temperature, the mass loss rate of the peaks and the final combustion temperature of blends combustion tend to increase. The Flynn-Wall-Ozawa (FWO) iso-conversional method is used for the kinetic analysis of the main combustion process. The results indicate that, when the waste plastics content varied from 0 to 40%, the values of activation energy increase from 126.05 to 184.12 kJ /mol.     

The Combustion Efficiencies of the Waste Plastics as Supplemental Fuel for Blast Furnace

The possibility of using waste plastics as a source of secondary fuel in the blast furnace has been of interest recently. In order to study the feasibility of injecting waste plastics into blast furnaces, the paper compares the combustibility of several kinds of waste plastics with that of pulverized coal. To improve the combustion efficiency of waste plastics in the blast furnace, the effects of plastic particle size, blast furnace temperature and different atmosphere were investigated in the laboratory. The result shows that compared with pulverized coal, waste plastics have lower thermal ignition temperature, shorter burning time, higher burning rate, lower ash ratio and higher calorific values, which are beneficial for blast furnace injection. With the increase of both the blast temperature and the level of oxygen enrichment, as well as the decrease in the particle size of waste plastics, the combustibility of waste plastics can be improved immensely. The optimization of blast furnace injection utilizing recycled plastics as a source of secondary fuel is possible by considering all these variables.     

高炉喷吹废塑料技术及应用前景

从废塑料喷吹后的燃烧分析、对高炉冶炼的影响、能量的利用等多方面分析了废塑料应用于高炉喷吹的可行性。并分析了国外高炉喷吹废塑料的实践与进展。分析表明：高炉喷吹废塑料的技术既为废塑料的综合利用和治理“白色污染”开辟了一条很好的途径,也为冶金企业节约能源提供了一种新的手段。     

废塑料与煤粉的热解特性对比及动力学研究

 采用热重分析法(TGA)研究了城市固体垃圾中的4种常见废弃塑料——废弃聚乙烯农膜(PE)、废弃聚苯乙烯泡沫塑料(PS)、废弃聚丙烯编织袋(PP)、丢弃的聚对苯二甲酸乙二醇酯饮料瓶(PET)和高炉喷吹用煤粉的热解特性,并计算出它们各自的热解动力学参数。结果表明：废塑料和煤粉的热裂解都属于一级反应,但是煤粉裂解温度远高于废塑料,而裂解量却远小于废塑料,在高炉高温条件下,废塑料将具有比煤粉更好的燃烧特性。     

Numerical Analysis of Pulverized Coal Combustion inside Tuyere and Raceway

The process of pulverized coal combustion inside the tuyere and raceway plays a very important role in the performance of a blast furnace. A three‐dimensional multiphase CFD model using Eulerian approach has been developed to simulate the coal devolatilization and combustion process inside tuyere and raceway. The velocity field, temperature distribution, and combustion characteristics have been determined in details and the effect of tuyere diameter on the pulverized coal combustion process has been predicted. Numerical results show that the pulverized coal combustion process displays different characteristics when the tuyere diameter changes. For a bigger diameter tuyere, there is more coal devolatilization, and combustion occurs inside the tuyere, which results in a better combustion condition compared to smaller tuyere diameters. The gas temperature distributions inside the raceway are dependent on the tuyure diameter; the temperature for the large size tuyere is higher than that of the small one. The coal burnout changes from 85.3% to 60.0% when the tuyere diameter reduces from 0.165m to 0.146 m.     

Recycling Rubber Tyres and Waste Plastics in EAF Steelmaking

Electric Arc Furnace (EAF) steelmaking uses different carbon based materials as foaming agents. Depending on cost and availability, anthracite and metallurgical coke are among the conventional injecting materials. Considering the energy and green house gas emissions requirements, alternative carbon sources are put on the spot to replace, at least partially, the conventional materials, i.e. waste materials such as rubber and high density polyethylene (HDPE) plastics may react with gas and slag phases resulting in devolatilization, combustion and iron oxide reduction reactions. The addition of waste tyres and waste plastics in EAF steelmaking has been studied in detail by our groups at UNSW and OneSteel is developing a method for EAFs to use blends of different proportions of rubber/HDPE plastics and coke as a slag foaming agent. Initially, laboratory investigations were carried out to establish the feasibility of carbon and polymer blends as foaming agents. The enhanced slag foaming performance compared to coke was found to be in good accordance with the results obtained in the laboratory indicating an increased slag volume when using polymeric blends. Following the successful installation of materials handling systems at both plants, the use of a rubber and coke blend is no longer considered a trial and is instead standard practice.     

废塑料与煤粉升温过程中的燃烧特性

试验研究废塑料燃烧特性。在空气和氧气的不同条件下,研究了不同品种废塑料颗粒和对比煤粉的燃烧特性。结果表明：在氧气条件下,不同品种废塑料升温时尾气中CO含量明显升高的温度都比在空气中的低30℃,CO2含量比在空气中的显著升高;在空气或氧气同一条件下,废塑料的CO2最大含量都比煤粉大幅提高,废塑料完成燃烧的温度比煤粉的低300~500℃。     

高炉喷吹废塑料工艺新探索

介绍了国内外高炉喷吹废塑料的研究进展,提出了煤与废塑料共熔喷吹的新思路,以期对我国“白色污染”的治理和冶金企业节约能源和降低成本提供一条新途径。     

高炉喷吹废塑料的先进技术

废塑料循环利用技术对于全球环境保护和社会发展都是一个非常重要的课题。JFE制钢公司为了将废塑料作为高炉的还原剂,通过热模燃烧实验;研究了废塑料的燃烧气化率。经过研究,为了改善粗粒废塑料的燃烧性,开发了同时喷吹煤粉或／和天然气的技术,为了提高废塑料的燃烧和气化率及炉内透气性,JFE开发出将废塑料与碳酸钙（CaC03）复合造粒技术。另外,JFE还研究了废塑料精细粉碎技术。此技术已经应用在实际生产中。