氮肥厂联产超细碳酸钙的有利条件分析

本文从以煤为原料并最终生产尿素的氮肥厂富余有大量的高纯度 CO2 等几个方面论述了氮肥厂联产超细碳酸钙的有利条件 ,这些有利条件不仅可使氮肥厂实现联产超细碳酸钙 ,而且对提高超细碳酸钙的产量和质量 ,以及大幅度降低投资成本都具有重要的意义。     

提高联合企业中化肥装置运行效益的措施

近几年来，化肥市场持续疲软，国内化肥生产厂的生产经营都面临着不同程度的困难，尤其以石脑油为原料的大化肥装置，因原料和燃料价格的上涨，都出现了严重亏损，笔者结合多年来的生产实践，提出依托企业联合优势，做好原料和燃料的优化，努力降低生产成本，同时通过外供氢气和液氨以分流产品，是提高化肥装置运行效益的重要措施之一。     

Marine macrofouling: a review of control technology in the context of an on-line experiment in the turbine condenser water box of Al-Jubail Phase-1 power/MSF plants

The problem of macrofouling has serious implications in the performance of desalination and power plants. Intake structures, screens, seawater piping systems and heat-exchanger tubes are the sites worst affected in the plants, causing an overall decline in plant efficiency at great economic cost. The last half century has witnessed significant advancements in the development ofmacrofouling control technologies. Materials of inherent antifouling properties are widely used in the construction sector. Control technologies available include antifouling paints and coatings, injection of biocides, marine bio-active compounds, materials of inherent antifouling properties, heat treatment, pulse-power devices, UV and nuclear radiation, scrubbing devices, biological control, etc. A literature search carried out during the last few years has yielded about 450 references. This paper presents, in a very concise manner, state-of-the- art macrofouling control technologies pertinent to desalination and power plants in the Kingdom. The paper also discusses the issues of biofouling control in the Al-Jubail plants based on the results of an on-line macrofouling experiment conducted in one of the turbine condensers of Al-Jubail phase-I MSF/power plants.     

Chlorophyll and plankton of the Gulf coastal waters of Saudi Arabia bordering a desalination plant

As on land, plants are the real producers in the sea, and on them depend all marine living resources and the basic sustainability of ecosystems. Primary production is performed by chlorophyll-bearing plants ranging from the tiny phytoplankton to the giant kelps through the process ofphotosynthesis. Zooplankton play an important role as secondary producers, and together with phytoplankton they support the vast assemblages of marine food chain with all their diversity and complexity. Data on chlorophyll pigments, phytoplankton and zooplankton are regarded as a sound basis for environmental appraisal of ecosystems. This paper presents a set of data collected from the Saudi Arabian coastal waters near the desalination plants in AI-Jubail. Materials were collected from six different sites covering the intake and discharge zones during cruises carried out in 1997-1998. Analyses of chlorophyll pigments were made using the spectrophotometric method. Plankton samples were collected using a Nansen plankton net with a mesh size of 75 μ and analyzed following standard procedures. Chlorophyll a, b, c and phaeophytin are the most commonly occurring pigments in seawater. Their concentrations showed wide fluctuation. The phytoplankton community was composed of 35 genera representing the Diatoms, Dinoflagellates and blue- green algae. Zooplankton were composed ofProtozoa, Coelenterata, Ctenophora, Aschelminthes, Annelida, Mollusca, Arthropoda, Echinodermata and Chordata. Arthropoda, represented by Cladocera, Copepoda and Crustacean larvae, formed the largest group followed by Chordata. The distribution of phyto- and zooplankton was examined and discussed on a seasonal, annual and inter-annual basis. In terms of species, overall species composition was not affected by plant discharge. The study brings out a greater understanding of the changes experienced by biotic communities as a result of impingement, entrainment and entrapment consequent to water passage through the plant structures. The study reflects the ecological relationships that the phytoplankton and the zooplankton of the region possess with respect to intake and discharge. Further, the study has brought to light a very redeeming feature of the ecosystem to sustain its productivity and planktonic abundance. It was observed that seawater temperature, conductivity and total suspended solids did not act as limiting factors. Besides throwing much light on the little known biological aspects of desalination sites, the data provided constitute a significant addition to the knowledge base of marine living resources in an industrial zone of Gulf coastal waters.     

Design of a Cost‐Reduced Flexible Plant for Supercritical Fluid‐Assisted Applications

A novel batch plant for supercritical CO₂ applications is proposed which is not equipped with expensive components, such as high‐pressure pumps, making it particularly suitable for bench‐scale use. For the first time, the use of a hanging scale is suggested to weigh the amount of CO₂ required for the experiment and the use of the thermodynamics to reach the working conditions. The rig is able to cover different applications, e.g., aerogel drying, impregnation, and extraction, showing high flexibility. An approximate cost analysis has been performed considering as a reference a 150‐mL vessel. It has been calculated that both the setup and running costs are considerably lower than the common batch and semicontinuous rigs.     

关于新疆热电厂职业危害分析与讨论

对比不同热电厂企业工人接触职业危害因素情况,分析原因,为在建或已建热电厂提供职业危害因素预防措施,降低企业由于设计、施工或管理方面原因造成后期运行过程中职业危害接触超标情况的发生。根据我室历年对新疆地区热电厂职业危害因素检测结果与评价报告的比较,找出不同热电厂职业病危害因素的共性及异性,分析不同设备、工艺及管理方式不同所造成职业危害因素检测结果的差异及原因。建议优化厂区工艺及土建设计;优化设备选型及原料选择运用现代化的管理手段,加强职业卫生管理体系宣贯的有效运作。     

关于EPS企业职业危害因素分析与讨论

对某EPS企业生产岗位或工种存在的粉尘、毒物、噪声、工频电场等职业病危害因素进行现场调查和检测,通过对其工艺流程及相关设备的操作过程进行分析,确认生产过程中的职业病危害因素产生的原因及分布。通过对检测结果数据进行分析与讨论,找到EPS企业职业病危害因素来源,了解其职业病危害控制效果,确认EPS企业职业病危害因素关键控制点,为在建或已建EPS企业提供职业危害因素预防措施。     

当归净油抗衰老及抗炎祛痘功效的体外实验研究

通过人真皮成纤维细胞(HDF-a)模型,考察了当归净油对细胞分泌Ⅰ型胶原蛋白(Col-Ⅰ)的影响。结果表明,当归净油在最大安全质量浓度25 mg/L时,能有效增加HDF-a细胞分泌Col-Ⅰ达33.5%。利用痤疮丙酸杆菌刺激人急性单核细胞THP-1,建立了特异性痤疮炎症细胞模型,考察当归净油对细胞分泌炎症因子人白细胞介素1β(IL-1β)的影响。结果表明,当归净油最大安全质量浓度为12.5 mg/L,此时对痤疮丙酸杆菌诱导的THP-1细胞炎症因子IL-1β分泌抑制率高达94.51%,当质量浓度减半为6.25 mg/L时,抑制率为64.34%。当归净油作为一种芳香性中草药,有望成为抗衰老及抗炎祛痘的个人护理天然原料,在化妆品中得到进一步开发和利用。     

工业建筑楼板振动控制研究

文章介绍了工业厂房楼板振动控制的必要性,并总结了可以作为评价楼板振动参考依据的三种规范。说明了楼板振动控制的主要方法,指出了现行方法的缺陷。介绍了调谐质量阻尼器的优势,提出了用调谐质量阻尼器进行楼板振动控制。     

冶炼烟气制酸中清洁生产的过程分析

介绍了冶炼烟气制酸行业的清洁生产现状。着重分析了冶炼烟气制酸过程中的污染物成因及热能利用情况,针对性提出了减少污染物外排、提高热能利用与节能的方案,为相关企业实现清洁生产的目标提供了参考。