转炉钢渣热闷技术在济钢的开发应用

通过对转炉渣在闷渣池内的集中喷淋水,并合理调整喷水压力、流量、闷制冷却时间,充分利用钢渣余热,使钢渣通过闷渣工艺处理后全部粉化.一方面彻底消除钢铁企业钢渣放炮事故的安全隐患;另一方面有效降低了钢渣粉尘导致的环境污染,为职工创造良好的工作环境.并可采取对粉化渣进行磁选工艺,能够提高钢渣二次利用率、渣中金属回收率,为企业降低成本、实现循环经济创造条件.     

钢渣资源化利用技术现况和探讨

介绍了目前我国钢渣预处理工艺和尾渣资源化利用的主要方法,并对钢渣的资源化利用发展进行了探讨。我国钢渣的资源化利用主要受到地域、钢渣性质以及市场3方面因素的限制。建议大力推广钢渣有压热闷等先进钢渣预处理技术,使钢渣处理更加高效、环保。钢渣尾渣用于制备胶凝材料和道路建设是大批量消纳钢渣的可行方法,应争取政府和财政的支持,推动跨行业的合作,促进钢渣的资源化利用。     

钢渣热态资源化利用新技术

简述了钢渣处理的现状 ,即大部分钢渣资源化工艺是先水淬处理 ,后综合利用 ,指出了这种传统钢渣处理工艺的缺点 ,提出了一种钢渣热态资源化利用的新技术     

改性钢渣颗粒吸附去除废水中磷的研究

利用酸、碱、盐、水及煅烧等对钢渣颗粒进行改性,研究改性方法、煅烧温度和煅烧时间对钢渣吸附除磷的影响,并通过表面特征分析、吸附动力学试验和吸附等温试验研究优选改性钢渣和未改性钢渣吸附除磷的特征.结果表明,粒径为0.9～2 mm的钢渣经过3mol/L NaOH浸泡24h和800℃煅烧1h改性后对磷的吸附效果最佳,最大吸附量可达13.39 mg/g,比未改性钢渣提高了60.75％.扫描电镜和比表面积分析可知,钢渣经碱改性后表面变粗糙,吸附孔径变小,比表面积和孔容变大.准一级动力学模型能较好地描述未改性钢渣对磷的吸附过程,碱改性钢渣的吸附动力学过程则符合Elovich模型.未改性和碱改性钢渣对磷的吸附过程均可用Langmuir吸附等温方程较好地拟合.     

钢渣综合利用的途径

在国外,钢渣一直被看作资源而加以利用.在美国,钢渣的利用已实现了专业化和企业化,70年代就已达到排用平衡.除钢厂自用的部分钢渣外,全国有27家较大的渣处理公司,年产值一亿多美元.日本钢渣的利用率也已达80%以上.     

钢渣综合利用的途径

介绍了钢渣的组成以及钢渣在钢铁冶炼、建材生产、环境工程、农业等方面综合利用的途径。     

国内外钢渣处理技术与综合利用技术的发展分析

介绍了国外钢渣综合利用概况,分析了我国钢渣处理技术与国外之间的差距.对存在的问题提出了建议.     

国内外钢渣处理技术与综合利用技术的发展分析

介绍了国外钢渣综合利用概况,分析了我国钢渣处理技术与国外之间的差距,对存在的问题提出了建议。     

典型钢渣的易磨性和胶凝活性分析

分析了25家钢铁企业转炉和电炉钢渣的易磨性和胶凝活性,分析结果表明,钢渣中的一些含铁物相,如橄榄石、铁酸钙类物质属于难磨物相,而RO相相对易磨,电炉氧化渣比转炉渣易磨,热闷渣比热泼渣易磨;碱度≥1.8的转炉钢渣的胶凝活性较好,能符合GB/T 20491—2006《用于水泥和混凝土中的钢渣粉》中规定的二级钢渣粉的活性指数要求,而电炉渣由于碱度偏低,胶凝活性较差。     

典型钢渣的f-CaO含量和稳定性分析

测试分析了25家大型钢铁联合企业钢渣样品中f-Ca O的含量、显微形貌以及钢渣的稳定性,测试分析结果表明,热泼转炉渣的f-Ca O的质量分数大多在4%以上,而热闷渣、滚筒渣和风淬渣的f-Ca O含量相对较小;电炉渣的f-Ca O的质量分数都在1%以下;转炉钢渣中存在2类f-Ca O,一类为死烧石灰,另一类由C3S在高温冷却过程中分解形成。钢渣的稳定性与钢渣的f-Ca O有显著的正相关性,要将浸水膨胀率控制在2%以下,f-Ca O的质量分数应当控制在3%以下,而要将压蒸粉化率控制在5.9%以下,f-Ca O的质量分数应当控制在2%以下。     

Coal dust emissions: From environmental control to risk minimization by underground transport. An applicative case-study

Coal dust emission from open coal storage parks and handling plants can represent a significant part of the overall atmospheric emission contribution in different industrial activities, such as power stations or coke production plants. The emissions are strictly connected to technical characteristics of the handling system, chemico-physical properties of coal and environmental conditions. In this paper, we present a full-scale operational solution to the problem of limiting coal dust emissions during transportation from the harbor site to the final utilization plant. To this end, a simple mathematical framework is developed in order to evaluate explosion risk inside the enclosure and set-up proper technical and managerial layers of protection suitable to minimize the risk.     

Effect of depithing on the safety and environmental aspects of bagasse stockpiling

Large scale sugarcane bagasse storage in uncovered stockpiles has the potential to result in adverse impacts on the environment and surrounding communities through hazards associated with nuisance dust, groundwater seepage, spontaneous combustion and generation of contaminated leachates. Managing these hazards will assist in improved health and safety outcomes for factory staff and reduced potential environmental impacts on surrounding communities. Removal of the smaller fibres (pith) from bagasse prior to stockpiling reduced the dust number of bagasse by 50% and modelling suggests peak ground level PM₁₀ dust emissions would reduce by 70%. Depithed bagasse has much lower water holding capacity (～43%) than whole bagasse.This experimental and modelling study investigated the physical properties of depithed and whole bagasse. Dust dispersion modelling was undertaken to determine the likely effects associated with storage of whole and depithed sugarcane bagasse.     

A real-time method for sensing suspended dust concentration from the light extinction coefficient

In powder handling and processing industry, location of dust emission can vary, with the suspended dust concentration assessment requiring installation of an immovable or wired equipment. For increased dust sensing, not limited by location within the facility, a portable suspended dust concentration measuring system is needed. In this study, a new method of sensing suspended dust concentration under daylight environment using the change in light extinction coefficient was developed. The method involves capturing images of the suspended dust cloud and then analyzing the light extinction coefficient. This method mitigated the environmental light scattering and absorption and eliminated the noise from the images obtained through a camera by calibration between two targets. Cornstarch, corn dust, and sawdust were used as test materials in this study. The light extinction coefficient (ε) was found to correlate with the suspended dust concentration, and the ε values depended on the dust properties. Mass extinction coefficient (K) was obtained for cornstarch, saw dust and corn dust, from known suspended dust concentrations using image analysis. The mass extinction coefficient of the three sample materials tested in this study were in the range of 0.03–0.04. This method of using light extinction coefficient can be used for real-time sensing of suspended dust concentration in both open and confined spaces.     

含锌废物综合利用项目环境影响评价工程探索

工业生产的废物当中包含多种重金属,例如钢铁厂的粉尘当中就含有锌。含锌粉尘不仅会在高炉内循环和富集,影响高炉的运行,还会造成环境污染。基于此,本文主要分析含锌废物综合利用,对该项目进行环境评价,探讨有效的对策,以提高含锌废物综合利用的科学性,提高环境保护等级。     

TSLCDM长袋低压脉冲布袋除尘器及其应用

为了使电炉烟气治理过程中污染源的排放达到国家排放标准,提出一种TSLCDM长袋低压脉冲除尘器(简称TSLCDM除尘器)。通过对该除尘器结构、除尘原理以及不同工况下除尘效率和过滤阻力的分析,得到该除尘器的除尘效率>99.9%,压力损失<1200 Pa,最终排出的烟气含尘质量浓度约5.54 mg/m3,满足了国家的超低排放要求,以泉州某公司电炉项目除尘系统为研究对象,证明了该新型脉冲布袋除尘器在电炉烟气治理除尘系统的应用效果,具有很好的经济和环境效益。     

某铁路货车检修车间污染治理分析

某车辆段货车检修中抛丸除锈、电焊、喷漆、探伤等工艺存在粉尘颗粒物、有机废气等职业危害因素。检测表明,电焊烟尘产生的粉尘颗粒物为主要污染源,急需治理。通过改造设置下送上回式的排烟除尘系统,车间污染情况得以有效改善,经检测室内粉尘满足工作场所有害因素职业接触限值要求,颗粒物排放满足国家环保标准要求。     

移动通风槽技术在攀钢炼铁高炉矿槽除尘系统的应用

采用移动通风槽技术对攀钢炼铁高炉矿槽除尘系统槽上原有吸尘点进行改造,改造后达到节能减排、降低成本的目的,具有一定的经济效益及环境效益.     

卸载破碎区域气动喷雾联合抑尘网除尘的数值模拟研究

为了有效治理安家岭煤矿输煤系统中卸载破碎区域的粉尘污染,提出卸载坑外围设置柔性抑尘网及坑口处设置气动喷雾的防尘方案。采用现场测试与三维数值模拟相结合的方法,得出卸载坑粉尘逸散规律。通过对卸载坑气动喷雾的雾化效果和设置抑尘网后的风速分布的数值模拟,分析该方案的除尘机理,并通过在安家岭煤矿的现场试验,验证该方案的可行性。结果表明:坑口处的气动喷雾能有效抑制坑内粉尘飞扬,外围设置的柔性抑尘网能有效控制坑口处的风速,防止粉尘受外界气流影响,有效降低粉尘污染浓度,其降尘效率达到90%以上,该综合除尘方案为输煤系统卸载破碎区域的粉尘治理提供理论依据。     

Influence of workpiece materials on aerosol emission from die sinking electrical discharge machining process

Simultaneous investigation of environmental emissions and machining aspects of electrical discharge machining process is essential for achieving hygienic and efficient machining. The main objective of the present work is to experimentally investigate and analyze the aerosol emission rate and the material removal rate from a die sinking electrical discharge machining process for three commonly used work piece materials viz., tool steel, mild steel and aluminum using Taguchi methodology of Experimental Design in order to suggest suitable process conditions for green manufacturing. The aerosol emission profile of all workpiece materials was found to be closely related to the material removal profile. A significant variation in emission and material removal rate was observed for workpiece materials which may be accorded to the variation in melting and vaporization temperatures. It was also observed that majority of aerosol constituents evolved from workpiece materials and that the constituents with low melting points were having high relative concentration in the aerosol emitted. The study introduced a parameter, the relative emission rate for comparing the emission for various process parameters and workpiece–tool material combinations. The favorable machining parameters for each material were then identified by employing signal to noise ratio analysis of the relative emission rate.