Precipitating spinel into precursor glass and its assistance in crystallization

The crystallization phenomena of spinel in CaO-MgO-Al₂O₃-SiO₂-Fe₂O₃ glass have received much attention due to the particular role in preparation of glass-ceramic materials, which represent an effective option to manage hazardous waste. In this study, both preliminary spinel and secondary spinel were precipitated in the precursor glass. The formation of these spinel was meticulously assessed by a combination of X-ray diffractometry and scanning electron microscopy. The structure of the microenvironment in the precursor glass was characterized by Raman spectrums. These advanced techniques highlight the potential for one-step crystallization of the glass. The investigation, which focused on one-step crystallization, demonstrated the growth of pyroxene on spinel accompanying a migration of chromium. The results also show the microstructure of the obtained glass-ceramic was very dependent on the heat-treat temperature. This study not only unambiguously reveals the precipitation mechanisms of spinel but also provides more documentation for one-step crystallization in the glass-ceramics field.     

化工企业实现清洁生产的策略评述

概述了世界银行推进中国清洁生产项目中１０家化工企业的清洁生产审计结果，总结分析了化工企业实行污染预防持续发展的策略，并对我国化学工业实现清洁生产提出了具体建议。     

木马盗号案件的侦查取证

木马不仅破坏计算机及计算机网络,而且对其进行控制,并窃取或篡改重要信息,不断对网络安全造成严重的破坏。另外,木马还被许多不法分子用作犯罪工具,造成巨大的经济损失,甚至扰乱社会治安。基于上述情况,对木马盗取网络虚拟财产的研究正受到人们的广泛关注。     

习家口油田集输系统清洁生产工艺改造

习家口油田单井管线腐蚀严重,经常发生管线穿口事故。由于伴生气量少,翻斗计量工艺无法运行。针对这种情况采用流量计计井口计量和树杖状串联常温集输工艺,降低了能耗,避免了运输油过程中的烃类气体的排放,减少了环境污染。据统计,习家口油田年减少烃类气体挥发100万方左右,生产运行费用大幅降低,取得了较好的经济效益。     

Cleaner production in Romanian textile industry: a case study

This paper reports the changes resulting from adopting environmentally sensitive criteria in Novatextile Pitesti, Romania. The changes have improved the operation of the production plant and reduced costs at the same time.     

浅谈纺织行业开展清洁生产审核

在广东,政府主要采取一种激励机制或者强制来推动纺织企业的清洁生产,推出鼓励节能、降耗和减污的政策,鼓励企业淘汰落后工艺和设备,限制有毒有害的原辅材料的使用。而企业作为实施清洁生产的主体,通过实施了清洁生产达到了节能降耗、减污增效的目的。本文主要通过总结纺织行业开展清洁生产审核的一些成功案例,以其指导其他同类型企业开展清洁生产审核。     

铬酸钾-碳酸钾高效分离研究Ⅰ.相图分析与溶解度计算

铬酸钾-碳酸钾的高效分离是铬盐清洁工艺亚熔盐介质再生的重要环节.据K2CrO4-K2CO3-H2O体系溶解度分析,蒸发结晶是该分离过程控制的关键,对此进行了详细的相图分析.选用Pitzer模型的HW公式,以二元电解质溶液的Pitzer参数推算了100℃时K2CrO4-K2CO3-H2O体系相平衡情况,理论计算结果与实验结果吻合较好,最大相对误差为16.26%,平均相对误差为7.39%.     

实施清洁生产之探讨

阐述了清洁生产的定义与内容,并结合我国的实际情况,解释了清洁生产的概念;指出了清洁生产与末端治理的区别,清洁生产与末端治理之间并非互不相容,而是长期并存的现实;对企业如何实施清洁生产审计工作提出了具体的看法和建议,着重论述了企业的清洁生产审计是由生产过程评价、清洁生产机会识别和清洁生产方案实施三个环节组成,它们的有机结合,形成了企业清洁生产审计的基本框架.     

Sulfur resource recovery based on electrolytic manganese residue calcination and manganese oxide ore desulfurization for the clean production of electrolytic manganese

An environmentally friendly and resource-conserving route to the clean production of electrolytic manganese was developed, in which the electrolytic manganese residue(EMR) was initially calcined for cement buffering;then the generated SO_2-containing flue gas was managed using manganese oxide ore and anolyte(MOOA) desulfurization; at last, the desulfurized slurry was introduced to the electrolytic manganese production(EMP). Results showed that 4.0 wt% coke addition reduced the sulfur of calcined EMR to 0.9%, thereby satisfying the cement-buffer requirement. Pilot-scale desulfurization showed that about 7.5 vol% of high SO_2 containing flue gas can be cleaned to less than 0.1 vol% through a five-stage countercurrent MOOA desulfurization. The desulfurized slurry had 42.44 g·L~(-) Mn~(2+) and 1.92 g·L~(-1) S_2 O_6~(2-), which was suitable for electrowinning after purification, and the purity of manganese product was 99.93%, satisfy the National Standard of China YB/T051-2015.This new integrated technology fulfilled 99.7% of sulfur reutilization from the EMR and 94.1% was effectively used to the EMP. The MOOA desulfurization linked the EMP a closed cycle without any pollutant discharge, which promoted the cleaner production of EMP industry.     

清洁生产——化学工业发展的最佳选择

介绍了化肥及基本化工的清洁生产技术。给出了直观推断法、质量交换网络综合法、摸拟优化法、灵敏度分析法、热力学分析法及产品周期分析法等６ 种清洁化工过程系统集成方法。