选钼中间矿浓缩溢流水回收及钼精矿干燥粉尘治理

介绍了德兴德矿对选钼中间矿浓缩溢流水循环利用所采取的措施和所取得成果,对原钼精矿干燥除尘系统存在问题进行了整治,达到了预期效果。     

钼精矿配料库防尘

钼精矿配料库是给焙烧炉供料用的。所配物料共三种:电除尘灰(焙烧炉烟气经电除尘器净化后的回收尘)、返回品(焙烧后不合格需返回重新焙烧的物料)和钼精矿粉。本配料库系苏联设计,于1956年投产。经过20多年运转,证明其工艺流程不合理。1.由于电除尘灰与返回品自由堆放,不时散发二氧化硫气体,且在倒、装物料过程中粉尘飞扬;2.打矿机的抽尘管道水平敷设,长10米多,几年后管道完全堵死。因此,工作     

三元络合物光度法测定水和废水中的微量钼

我们研究了溴邻苯三酚红—十六烷基三甲基溴化铵—钼三元络合物光度法,用来测定水和废水中的微量钼。三元络合物表观克分子吸收系数为6.9×10~4。0～75微克钼/50毫升符合比尔定律。此法选择性好,灵敏度、准确度高,显色快而稳定。可测 ppb 级的钼。     

钼选矿项目清洁生产分析评价

钼选矿是高能耗、高物耗、高污染的行业.鉴于目前我国尚未制定钼选矿方面的清洁生产标准,从生产工艺与装备、资源能源利用、污染物排放、废物回收综合利用、环境管理等五方面进行定性或定量分析,得出项目是否符合清洁生产原则的明确结论,并提出项目改进的实施途径和建议,为该类项目清洁生产评价提供一定的指导.     

铁钼催化氧化法制甲醛的安全技术分析

通过对铁钼氧化法制甲醛生产过程中物料及工艺的分析,指出各个环节中存在的危险性并提出对策。     

PC-88A萃取钴钼废催化剂浸取液中Co2+的工艺研究

对废催化剂中有价金属的回收方法及工艺进行了研究。工厂所得钴钼废催化剂的组成为:以氧化铝为载体,钴、钼的质量比分别为0.030 g/g、0.110 g/g。依据不同p H值下废催化剂所含钴和钼金属离子存在形式及价态不同、从而引起金属萃取率E有差异的原理,确定了采用酸性萃取剂PC-88A在酸性条件下萃取回收钴钼废催化剂浸取液中有价金属的工艺。重点开展Co2+的萃取回收,考察了水相p H值、萃取剂体积分数、相比(V(有机相)/V(水相))、搅拌时间、搅拌速率及萃取温度等工艺参数对萃取率的影响,确定了Co2+回收的最佳工艺条件。结果表明,水相p H≈4.5、萃取剂体积分数为15%、相比为3∶1、搅拌时间为30 min、搅拌速率为500 r/min、温度为24℃的条件最有利于Co2+的萃取,其萃取率高达95.78%。     

镍钴钼精密合金酸洗废液处理与回收的研究

试验研究了含Ni、Co、Mo等精密合金酸洗废液处理与回收的方法,该方法可有效改善为去除精密合金热轧带材表面氧化皮所产生的酸洗废液对环境的污染,并且可充分回收镍、钴、钼稀有贵重金属,使资源获得再利用.     

钼兰比色法测定粉尘中游离二氧化矽

对粉尘中游离二氧化矽的测定,以前常用焦磷酸重量法。这种方法测定结果虽然准确,但分析时间长,需要样品量大,操作技术较难掌握。钼兰比色法测定二氧化矽,需用样品量少,可用测定粉尘重量浓度后的样品进行分析,操作简单,测定时间短,我矿试用两年,效果较好。一、测定原理及方法在800～900℃的高温下,碳酸氢钠,氯化钠的混合溶剂与矽酸盐不起作用,但能熔融二氧化矽,生成可溶性偏矽酸钠。在酸性     

铂载钴钼二元硫化物对H_2S电催化活性研究

为考察溶胶凝胶法制备的Co-Mo二元硫化物对H_2S气体的电催化活性,通过循环伏安法和Tafel曲线分析对铂载不同Co、Mo掺杂比的电催化剂进行表征.结果表明,不同阳极电催化剂交换电流密度J_0由大到小依次为,铂载n(Co):n(Mo)=2:3、铂载n(Co):n(Mo)=2:1、铂载n(Co):n(Mo)=1:1和铂,即铂载n(Co):n(Mo)=2:3阳极电催化剂具有较好的活性,这与循环伏安曲线测试结果一致.电解质溶液pH值为6～7时,随着温度的升高铂载n(co):n(Mo)=2:3阳极电催化剂活性呈现上升的趋势.优化后的Co、Mo掺杂原子比约为0.66,此类电催化剂在操作温度80℃下,交换电流密度为1.318mA/cm~2,表观活化焙值为616.6 kJ/mol .研究表明,铂载钴钼二元硫化物适合作为低温H_2S燃料电池阳极电催化剂,其中Co、Mo掺杂比对电催化活性影响较大.     

我国研究出尾矿变废为宝新技术

中国环境科学学会组织的成果鉴定会上公布,我国研究人员研究出一种将采矿企业的“垃圾”——尾矿加工为多元素矿质肥的新技术。这对解决因采矿带来的占地、污染和事故隐患具有明显的现实意义。该技术通过类似于水泥生产的简单工艺,将钼尾矿加工为含有对农作物生长所必需的钾、硅等多元素矿质肥。3年来,经过对多种作物、300多个点次的田间试验,结果表明该肥料对农作物具备增产、提高品质以及抗病虫害和抗旱涝低温等良好肥效。     

Customers as contributors and reliable evaluators of creativity in the service industry

Using hair stylists, we examined the nature of creativity in a service setting and the impact of customers as part of the social context for employee creativity. We also assessed whether customers could serve as reliable evaluators of creativity. To do so, we collected data from multiple sources: service providers, supervisors, and customers. Results demonstrated that customer input and customer affective‐based trust made significant, positive, and independent contributions to service‐related creativity. Moreover, customers in the service industry proved to be reliable raters of employee creativity, compatible with supervisors. Finally, input and trust were associated differently with service‐related and organization‐related creativity. Copyright © 2008 John Wiley & Sons, Ltd.     

通信铁塔影响建筑物防雷安全计算公式之合理性探讨

以一个发生过严重雷灾事故的屋顶通信铁塔为例,分别利用国际电信联盟ITU-K56《无线通讯基站的雷电防护》和国际电报电话咨询委员会CCITT《防雷手册》中的公式计算出建筑物安装了通信铁塔后的年预计雷击次数,并将之与未安装通信铁塔时的年预计雷击次数进行对比,两者的计算结果存在显著差异。基于雷击条件相似原则,参照移动公司通信铁塔每年遭受雷击次数的实际统计数据,对这两个计算公式的合理性问题进行了探讨。研究结果表明,CCITT《防雷手册》中的计算公式更具合理性,计算结果更加接近实际值,计算方法更能准确地评估铁塔对所在区域的建筑物及电子电气设备的防雷安全所造成的影响。     

南水北调中线干线工程安全生产管理体系策划方案研究

南水北调中线路干线工程是国家重点建设工程,该工程规模大、覆盖范围广、施工战线长、技术复杂、管理难度大,工程建设对安全生产管理工作提出了很多现时的要求,安全生产工作直接影响着工程的建设质量。根据工程建设的特点,结合现代安全生产管理的要求,笔者提出了“12345”的安全生产管理模式,在实际安全生产管理工作中发挥着很好的作用,为类似工程项目的安全生产管理工作提供了很好借鉴。     

PTA锻焊反应器的制造

本文对PTA装置上的大型铬钼钢锻焊反应器,在制造过程中的几个关键技术进行了介绍：控制材料的化学成分提高铬钼钢材料的抗回火脆化能力;采用先进的冶炼工艺和锻造技术保证大型锻件的质量;优化铬钼钢封头正火热处理中的冷却工艺来保证材料的性能指标;采用合理的焊接工艺,既保证了厚壁环焊缝的焊接质量,又降低了制造成本;优化堆焊工艺,保证了反应器内壁的堆焊质量;正确选择热处理规范,对铬钼钢压力容器至关重要。     

Spatial relationships between alcohol outlet densities and drunk driving crashes: An empirical study of Tianjin in China

Introduction: Numerous studies have demonstrated the close relationship between alcohol availability and alcohol-related crashes. However, there is still a lack of spatial empirical analysis regarding this relationship, particularly in large cities of developing countries. Differences in alcohol outlets and drinking patterns in these cities may lead to quite different patterns of crash outcomes. Method: 3356 alcohol-related crashes were collected from the blood-alcohol test report of a forensic institution in Tianjin, China. Density of alcohol outlets such as retail locations, entertainment venues, restaurants, hotels, and companies were extracted based on 2114 Traffic Analysis Zones (TAZ) together with the residential and demographic characteristics. After applying the exploratory spatial data analysis, this research developed and compared the traditional Ordinary Least Square model (OLS), Spatial Lag Model (SLM), Spatial Error Model (SEM) and Spatial Durbin Model (SDM) to explore spatial effects of all the variables. Results: The results of incremental spatial autocorrelation show that the most significant distance threshold of alcohol-related roadway traffic crashes is 3 km. The SDM is found to be the optimal spatial model to characterize the relationship between alcohol outlets and crashes. The number of alcohol-involved traffic crashes is positively related to population density and retail density, but negatively related to the company density, hotel density, and residential density within the same TAZ. Meanwhile, dense population and hotels have reverse spillover effects in adjacent zones. Conclusions: The significant spatial direct effect and spillover effect of alcohol outlet densities on drunk driving crashes should not be neglected. These findings could help improve transportation planning, traffic law enforcement and traffic management for large cities in developing countries.     

The role of built environment on pedestrian crash frequency

This study investigates (i) the link of land use and road design on pedestrian safety and (ii) the effect of the level of spatial aggregation on the frequency of pedestrian accidents. For this purpose, pedestrian accident frequency models were developed for New York City based on an extensive dataset collected from different sources over a period of 5 years. The assembled dataset provides a rich source of variables (land-use, demographics, transit supply, road network and travel characteristics) and two different crash frequency outcomes: total and fatal-only collision counts. Among other things, it was observed that the census tract analysis (disaggregate data) provides more insightful and consistent results than the analysis at the zip code level. The results indicate that tracts with greater fraction of industrial, commercial, and open land use types have greater likelihood for crashes while tracts with a greater fraction of residential land use have significantly lower likelihood of pedestrian crashes. Moreover, census tracts that have a greater number of schools and transit stops - which are determinants of pedestrian activity - are more likely to have greater crashes. Results also show that the likelihood of pedestrian-vehicle collision increases with the number of lanes and road width. This suggests that retrofitting or narrowing the roads could possibly reduce the risk of pedestrian crashes.     

基于Matlab软件的突发事故水质解析模型与应用

为快速分析突发性水污染事故可能造成的水环境影响,建立了基于Matlab软件的突发事故水质解析模型。以浙江省某河流为例,分析了上游突发水污染事故形成的污染团在河流中的迁移扩散规律、影响范围、事故下游各断面水质变化过程以及取水口等敏感点的超标时间及超标程度。同时详细分析了近岸和远岸边界对污染物反射所造成的浓度叠加影响、合理的边界反射次数,以及水流流速、扩散系数、降解系数等主要水文水质参数对污染团扩散的影响。     

世纪之交的中国职业卫生

简要地回顾了现代职业卫生的进步历程并展望了今后的发展趋势。依据近年职业病统计报告数据 ,分析了 90年代中国职业卫生工作的特点与问题。结合当前中国经济、社会现状 ,分析了 2 1世纪中国职业卫生所面临的挑战 ,提出了加强法制建设、建立三方协调机制、推行 OHSMS、发挥工伤保险预防作用和推广企业安全卫生文化等建议。