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青霉素废菌丝体是一种制药行业的危险固体废弃物。利用其富含蛋白质的特点,采用微波加热水解法制备一种新型建筑石膏缓凝剂(WPM缓凝剂),同时将制备缓凝剂后的滤渣用于制备活性炭。经过实验研究,确定的缓凝剂制备适宜工艺条件为:温度80 ℃,pH值11,时间10 min。得到滤渣制备活性炭的最佳工艺条件为:炭化时间为1 h,炭化温度为300 ℃,活化剂ZnCl2浓度为20%,液固比为3.0。 本工艺较好地解决了焚烧处置、堆放填埋或直接生产活性炭等处理方法造成的环境二次污染问题以及用作动物饲料可能导致的抗生素滥用问题,实现了青霉素废菌丝体的安全、清洁利用。 相似文献
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以工业副产物脱硫建筑石膏为原料,采用超细钢渣-矿渣-电石渣(SGC)复合胶凝剂和废玻璃钢纤维对其进行改性研究,得到适宜的改性条件为:复合胶凝剂适宜掺量为20%~25%,废玻璃钢纤维最佳长度为10~15 mm,适宜掺量为1.0%,且经过EDTA溶液浸泡处理的废玻璃钢纤维对石膏基体的改性效果较好。改性后石膏制品的软化系数提高到0.91,抗折强度为7.6 MPa,抗压强度为23.4 MPa,耐水性与力学强度显著提高,实现了不同工业废弃物的协同处置和脱硫石膏的高质化利用,也为难以处置的玻璃钢废弃物找到一种有效利用途径。 相似文献
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Many reports and studies have noted that a significant portion of problem-oriented coastal science does not actually link to decisions. Here, three competitively funded project case studies are studied to determine what funders can and should do to better link science with decisions. The qualitative analysis used for this study indicates that the studied program was seen as being unusually attentive to the issue of linking science to decisions, as opposed to simply generating new knowledge. Nevertheless, much of the data indicate that funders can and should do more. Three ideas figured most prominently in the qualitative data: (1) funders should do more to ensure that the problem itself is defined more thoroughly with people who are envisioned as potential users of the science; (2) funders need to allocate more resources and attention to communicating effectively (with users) throughout the project; and (3) funders need to demand more engagement of users throughout the project. These findings have important implications for how funders review and support science, especially when competitive processes are used. Most importantly, funders should adjust what kind of science they ask for. Secondly, funders need to change who is involved in the review process. Currently, review processes focus on knowledge generation, which means that the reviewers themselves have expertise in that area. Instead, review panels should be balanced between those who focus on knowledge generation and those who focus on linking knowledge to decisions; this is a separate but critical discipline currently left out of the review process. 相似文献
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对水杨酸钠-次氯酸钠法测量海水氨氮化学分析条件进行了研究。通过正交实验对水杨酸钠-次氯酸钠法试剂配比进行优化,并确定了最佳试剂配比。同时,用水杨酸钠-次氯酸钠法和靛酚蓝法测量24个海水水样,测量结果无显著差异。在反应温度为35℃,反应时间为10 min时,用改进后的方法分别测量60、120μg/L的氨氮标准溶液,相对标准偏差分别为4.0%、2.8%,回收率分别为99.8%、100.8%。该方法试剂无毒、环保,操作简单、快速,可满足营养盐自动分析仪现场快速测量的要求,提高仪器的环境友好性。 相似文献
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Each year more people die from diseases caused by work than are killed in industrial accidents. Therefore, methods are needed to evaluate occupational health hazards as early as possible when the process is still under development. A method for estimating inhalative exposures and risks in petrochemical and related plants is presented. The method is simple and suffices with the limited data availability during the early design stages.The steps of the method, which utilizes preliminary process flow diagrams are as follows: first the fugitive emissions and process plot areas are estimated based on precalculated process modules representing the typical process sections (such as a distillation unit). Chemical concentration in the air is then calculated based on the wind velocity probability and the estimated process cross-sectional area. For this purpose a typical wind velocity distribution in the area is used. The worker risk of exposure to chemicals is evaluated either based on the concentration in air by using the hazard quotient method or calculating the carcinogenic chemicals intake and the resulting risk of cancer. The values are compared to the benchmarks.As a result the process route health characteristics such as fugitive emissions rate, critical wind speed, chemical concentration in air and intake amount as well as the corresponding risk of exposure are produced. By using statistical meteorological data, health risks of occupational exposure can be estimated more realistically as probabilities. The approach is capable of comparing alternative processes to select the concept which is inherently occupationally healthier. Using this method, the exposure problems of a process can be identified earlier and proper decisions can be made early in process development or predesign stage.The concentration-based method is demonstrated by a case study of six competing manufacturing routes for methyl methacrylate (MMA). The C3 is found to be the most harmful alternative to health. Both concentration-based and intake-based methods are applied. The study indicates that the intake-based risk estimation benchmark is stricter than the exposure limit-based benchmark for carcinogens. 相似文献
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Mimi H. Hassim Markku Hurme Paul R. Amyotte Faisal I. Khan 《Journal of Loss Prevention in the Process Industries》2012,25(5):820-829
Fugitive emissions are among the major concerns of industrial process releases. The emissions cause problem to various aspects including the environment, health, and economic. Early evaluation of process hazards is beneficial because process can be made inherently benign at lower cost. This paper discusses two important aspects of fugitive emissions assessment during process design – the quantification and the prevention strategies.For the quantification part, three methods are presented for fugitive emissions estimation during the process design. They are tailored to data available in simple process flow diagram (PFD), detailed PFD, and piping & instrumentation diagram (PID). Such methods are needed as early emissions estimation allows production routes and process designs with lower emissions to be selected. The fugitive emissions estimation and methods to abatement are demonstrated on a benzene process case study. Valves are found to be the major emission source with 50% of fugitive emissions of process area in a base case of petrochemical process, in which no fugitive emission reductions are yet made. Pumps without mechanical seals come second with 30% and flanges with 8% of emissions. Inherently safer design keywords can be applied to prevent fugitive emissions in the process plants. Substitution is the most applicable keyword in fugitive emission reduction of existing plants.The emission rate calculations together with estimation of health risk give a sound background for the decision making on elimination of emissions at source through equipment and piping changes. The case study presented reveals that by substituting emission prone components by inherently low-leaking ones, the plant emissions can be reduced over 90% in practice. This is created mainly by replacing rising stem valves with ball valves, installing double mechanical pump seals or hermetic pumps and making changes in sampling and relief systems. Ideally by also changing flanges to welded connections, which is not viable for various reasons, the emissions could be reduced nearly to zero. 相似文献
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Mimi H. Hassim Markku Hurme 《Journal of Loss Prevention in the Process Industries》2010,23(3):476-482
Chemical process routes can already be assessed as early as in the development and design phases. Process screening should not look at economic and technical aspects only, but also the safety, health, and environmental performances. In this paper, a method called the Health Quotient Index (HQI) is presented for the preliminary process design phase. The HQI provides a simple approach to quantify workers' health risk from exposure to fugitive emissions e.g. in petrochemical plants. The method utilizes process data from flow sheet diagram, which is already available at the preliminary design stage. Since the mechanical details of the process are still unknown, a database of the precalculated fugitive emissions for typical operations in chemical plants was created to simplify the assessment. The HQI can be used to rank alternative process concepts or to quantify the risk level of processes. As a case study, six process routes for producing methyl methacrylate are discussed. Three health indexes are compared in the case study. The HQI is able to highlight the difference of hazard levels between the routes better as a result of more detailed assessment of the exposures. 相似文献
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Mimi H. Hassim Markku Hurme 《Journal of Loss Prevention in the Process Industries》2010,23(2):260-268
Each year more people die from work-related diseases than are killed in industrial accidents. Therefore it is essential to evaluate occupational health aspect during the process design. Early evaluation of safety, health, and environmental (SHE) performance is advantageous, since the opportunities to make the process inherently benign are greater and the cost therefore lower. The methods for occupational health assessments need to be tailored to specific design stages, since the data availability is changing as the design proceeds. In this paper, an index-based method called the Occupational Health Index (OHI) is presented for the basic engineering stage. The OHI is the final of the three methods in series proposed for health assessment in development and design stages. The OHI is based on the information available in piping and instrumentation diagrams (PIDs) and the plot plan. Four health aspects are considered; chronic inhalation risks to noncarcinogens and carcinogens, acute inhalation risk, and dermal/eye risk. The index is demonstrated on separation system of a toluene hydrodealkylation process. The assessment results allow the level of occupational health risks to be evaluated, the sources of exposures be detected, and corrective actions taken in a focused way. 相似文献