我国燃煤电厂除尘技术路线选择问题分析

通过文献调研分析了影响我国燃煤电厂除尘技术路线选择的主要问题,从煤质含硫量、粉尘比电阻、粉尘粒径分布三方面研究结果表明电除尘技术对我国煤种的适应性较差,无法满足严格的排放标准;另外,通过前人对比不同除尘方式协同脱汞效果和对下游设备保护作用的研究成果,结果表明袋式除尘器具有更好的协同脱汞作用,更高的除尘效率并赋予湿法脱硫设备长期可靠运行。     

Properties of steel foundry electric arc furnace dust solidified/stabilized with Portland cement

Electric arc furnace dust from steel production is generated in considerable amounts worldwide and needs to be treated as hazardous waste. The aim of this study was to investigate the properties of electric arc furnace dust solidified/stabilized by using Portland cement. Mortar and paste samples were prepared with varying waste-to-binder ratios between 0% and 90%. A comprehensive experimental program was designed including XRF characterization, setting time, unconfined compressive strength, and toxicity characteristics leaching procedure (TCLP), synthetic precipitation leaching procedure (SPLP), and acid neutralization capacity (ANC) tests. The results were evaluated in order to determine if the solidified /stabilized product can be disposed of at a landfill site with domestic waste or at a segregated landfill. The effect of using sand on S/S performance was also investigated. The results indicated that the solidification /stabilization process using PC helps the heavy metals to be bound in the cement matrix, but the TCLP leaching results exceeded the EPA landfilling limits. The SPLP leaching results conformed to the limits implying that the waste or S/S products can be disposed of at a segregated landfill; however the low ANC of the S/S products reveals that there may be leaching in the long-term. The sand used in the mortar samples adversely affected the S/S performance, causing higher heavy metal leaching levels, and lower pH levels in the leachate after the TCLP extraction than those measured in the leachate of the paste samples.     

Impact of utilizing reflector,single-axis and two-axis sun trackers on the performance of an evacuated tube solar collector

ABSTRACT

In this paper, a novel evacuated tube solar collector (ETSC) is first designed and built. Then, the impact of adding reflector, reflector plus single-axis sun tracker and reflector plus two-axis sun tracker to the built ETSC on the thermal efficiency of the ETSC is evaluated both theoretically and experimentally. In this regard, four identical versions of the proposed ETSC have been built and utilized in four collectors built and presented in this research work. The first collector is the same proposed built ETSC, the second collector is a parabolic trough solar collector comprising one built ETSC and a reflector (ETSC+R), the third collector is composed of one built ETSC, a reflector and a single-axis sun tracker all built in this study (ETSC+R+ ST), and the fourth collector consists of one built ETSC, a reflector and a two-axis sun tracker all built in this study (ETSC+R+ DT). Theoretical basis and concepts of the four collectors are formulated and analyzed in separate subsections. Theoretical results are outlined and highlighted at the end of each subsection. Experimental measurements and data obtained from the operation of the four collectors in the four seasons are presented that point by point verify theoretical results obtained in this study. To provide a comprehensive view, a techno-economic numerical comparison is performed between the four collectors. The following points, which are also the novelty and contributions of this work, are deduced from theoretical concepts, experimental data, and comparison provided in this study:

?There is no technical and economic justification for adding a reflector to an ETSC that results in forming a parabolic trough solar collector (ETSC+R) without any sun tracker.

?There is no economic justification for adding a single-axis sun tracker to a parabolic trough solar collector (ETSC+R).

?There is no economic justification for adding a two-axis sun tracker to a parabolic trough solar collector (ETSC+R).

?Comparing between a two-axis sun tracker and a single-axis sun tracker, adding the single-axis type to a parabolic trough solar collector (ETSC+R) is more advantageous.     

提高矿石块矿率减少粉尘危害

介绍了通过降低炸药消耗,改善爆破效果,提高原矿合格率,减少粉矿率,降低粉尘对周边的危害。     

水泥厂生料库底除尘系统的改造

分析了原设计中存在的问题,提出了改造措施和方案,并介绍了改造后的结果。     

复合多管除尘器用于链条锅炉烟气除尘

针对链条锅炉烟气旋风除尘器改造,介绍惯性沉降—旋风复合型除尘器用于燃煤链条锅炉烟气除尘。     

奥利安耐火材料有限公司的原料粗碎除尘系统及改进建议

介绍了某耐火镁碳砖车间粗碎工艺、除尘系统的运行状况及除尘效果.并提出了改进建议。     

煤磨收粉系统的改造

武钢炼铁厂10t/h煤磨系统四套,采用三级除尘(旋风、多管与袋式除尘)和两级风机(排粉机与抽风机)的收尘系统。能耗高、尾气排放超标、故障率高、安全性能差。于1993～1996年相继对四套系统进行改造,获得令人满意的效果,实现节能、降耗、增产、安全生产,达到环保标准。     

MPS型抑尘剂在兰尖铁矿道路的应用

通过对兰尖铁矿使用MPS型抑尘剂的概述,其良好的防尘性能、经济效益及社会效益必将为广大的市场所认同。     

排尘风机的选择与改进

论述了选择高浓度尘气排尘风机时必须考虑的一些主要因素,提出了在高浓度尘气情况下对现役风机进行改进的办法