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1.
生物膜填料塔净化甲醛废气实验研究   总被引:4,自引:1,他引:3  
采用微生物菌种对生物膜填料塔进行挂膜作业,以低浓度甲醛废气为研究对象,对生物膜填料塔净化甲醛废气进行了研究,考察了入口气体甲醛浓度、气体流量、循环液喷淋量各因素对甲醛净化效率和生化去除量的影响.实验结果表明,随着入口气体中甲醛浓度的增加,净化效率呈下降的趋势,而生化去除量却随之增加.气体流量增加时,净化效率较稳定,基本维持在65%左右,同时生化去除量随之增加.当液体喷淋量由10 L/h增至20L/h时,净化效率由40%左右增至约80%,再继续增加液体喷淋量时,净化效率的增加却渐趋平缓;当液体喷淋量增至40 L/h时,净化效率则为90%左右.生化去除量随着液体喷淋量的增加随之增加,当增至20 L/h时,增加趋势增大.实验结果表明采用生物膜填料塔净化甲醛废气是可行的.  相似文献   

2.
生物膜法净化低浓度SO2气体的工艺条件研究   总被引:1,自引:1,他引:0  
采用生物膜填料塔净化低浓度SO2气体,研究其适宜工艺条件.结果表明,SO2进口气体质量浓度2 500~3 500 mg/m3、气体流量0.1m3/h、循环液流量10~12 L/h、24℃、循环液pH<1.7时,生物膜填料塔对SO2的净化效率可达97.2%以上,对SO2生化去除量达52~56mg/(L·h).本研究为生物法脱除烟气中低浓度SO2提供了参考.  相似文献   

3.
采用改进的排泥挂膜方式进行微生物挂膜,扫描电子显微镜观察生物膜表面生物形态,探讨进气速度、停留对间、液体喷淋量、容积负荷等主要因素对不同浓度甲醛气体去除效率的影响.结果表明,驯化30d脱除甲醛的生物膜已基本成熟,生物膜表面长有大量真菌丝、原生及后生动物;优势菌体形态为球状和杆状,其中球菌直径2~2.5μm,且为中空网状的多孔性球团.通过对生物膜填料塔净化效果的研究,得到最佳工艺参数.当甲醛质量浓度为10~40 mg/m3,停留时间为27s,液体喷淋量20~40 L/h,容积负荷1~ 7.5 g/(m3·h)时,生物膜填料塔对甲醛的去除效率达到94%以上.  相似文献   

4.
介绍了恶臭污染物的来源、危害及其治理方法,分析了生物法除臭的发展,着重对生物滴滤塔除臭系统进行了介绍。总结了生物滴滤塔除臭的影响因素,分析了生物填料的发展,并比较了不同填料的理化性质及其除臭性能。简要归纳了工艺操作参数对生物滴滤塔除臭性能的影响。详细列举了应用于生物滴滤塔除臭的降解菌的种类及其功能。综述了填料上恶臭组分的传质和降解规律,总结了国内外关于生物膜内恶臭组分的降解反应动力学模型。同时介绍了生物滴滤塔在市政除臭和工业除臭方面的应用实例,并对生物滴滤塔理论研究与应用中存在的不足进行了分析,提出了可能的解决途径。今后可加强研究的方向有生物填料的开发与改良、生物滴滤塔的模型化设计及生物除臭组合工艺。  相似文献   

5.
将填料装入生物滤塔之前,对其进行挂膜驯化培养,待其成功后即可装填使用。试验结果表明,第12d后,发现树皮表面长有生物膜。在没有营养盐供应的情况下,微生物依然可以利用有机填料作为碳源进行代谢反应。42d后,从生物膜的镜检和混合液的pH值变化可知,用于除臭的优势微生物驯化成功。  相似文献   

6.
通过试验对粒径介于0.25~0.50mm的花生壳颗粒吸附Cr(Ⅵ)的动力学行为进行探讨,从吸附时间、pH值、吸附剂投加量、温度、Cr(Ⅵ)的初始质量浓度方面对吸附性能的影响进行研究.结果表明,最佳吸附条件为:Cr(Ⅵ)初始质量浓度100 mg/L,pH=2.0,振荡速度140 r/min,温度30℃.此时Cr(Ⅵ)的吸附率可达到90%以上.用Lagergren一级吸附速率方程、二级吸附速率方程及平均绝对偏离率对以上因素对吸附件能的影响数据进行处理,发现二级吸附动力学模型可以更好地描述各种影响因素条件下的吸附过程.二级吸附速率常数随着溶液pH值和Cr(Ⅵ)初始质量浓度的减小而增大.在低浓度和低pH值的条件下,Cr(Ⅵ)主要以HCrO4-形式存在,并且HCrO4-是花生壳主要吸附的Cr(Ⅵ).二级吸附速率常数随着溶液温度的升高而快速的增加.温度对反应速率的影响可以通过Arrhenius方程来描述,所得曲线近似为直线方程,决定系数R2=0.986 2,反应的活化能Ea为8.67kJ/mol,该反应活化能在物理吸附反应活化能范围(0~40 kJ/mol)内.  相似文献   

7.
锌合金工业白烟治理的实验研究   总被引:1,自引:0,他引:1  
填料塔洗涤吸收净化工艺在化工领域和低浓度工业废气净化方面均能很好地发挥作用.以水为吸收剂,应用填料塔对锌合金白烟进行吸收操作,试验结果显示:锌白烟的主要成分是氯化铵烟尘,其粒径在1μm以下,极不易溶于水,导致该工艺对氯化铵烟尘的处理效率仅在70%左右.烟气中氯化氢和氨气的浓度较低,经过处理已经达到排放标准.尽管氯化铵烟尘的处理效率低于预期,但实验研究对锌合金白烟的治理仍有重要的指导意义.  相似文献   

8.
柚子皮生物炭的制备及对水体中锰离子的吸附   总被引:1,自引:0,他引:1  
以柚子皮为原料经硫化钠活化后炭化处理制备了生物质炭吸附剂,并将之应用于含锰废水的吸附。考察了溶液p H值、底液质量浓度、生物炭投加量等因素对柚子皮生物炭吸附能力的影响,并研究了柚子皮吸附剂对锰离子废水的吸附平衡和动力学特征。结果表明:柚子皮吸附剂对含锰废水具备较强吸附能力,在溶液p H值为6,底液质量浓度为50 mg/L,吸附剂投加量为2 g/L的条件下,对锰离子的去除率为93.5%;吸附平衡实验表明该等温吸附过程符合Langmuir方程,饱和吸附量为24.691 mg/g;吸附动力学研究表明,该吸附过程符合二级动力学方程,吸附速率常数为0.028 6 g/(mg·min)。  相似文献   

9.
研究生物滴滤法间接催化氧化脱除H2S气体的动力学特性.基于吸收反应的双膜理论和生物膜理论,可以将H2S的脱除过程视为传质与氧化吸收的串联过程,而该过程又与Fe2+在生物膜内的传质及生化反应过程存在并联关系.通过分析得出液膜内H2S浓度分布模型及生物膜内Fe2+浓度分布简化数学模型.本研究得到的H2S去除率模型可为生物滴滤法的工艺设计和应用提供理论依据.  相似文献   

10.
实验研究了工业废弃物改性粉煤灰对Cr(Ⅵ)吸附的影响因素,讨论了pH值、浓度、温度及时间对吸附量的影响。讨论了反应机理,计算反应热力学参数(焓、自由能、熵)。实验结果表明,当Cr(Ⅵ)初始质量浓度为10 mg/L,反应温度303 K,pH=1时,吸附量最大为0.47 mg/g。吸附过程符合兰格缪尔等温吸附。吸附过程为自发进行的放热反应。反应温度为303 K时,反应过程的焓值为-3.529 kJ/mol,自由能-4.664kJ/mol,熵3.746 J/(mol.K)。反应动力学过程表明反应符合准二级动力学反应。  相似文献   

11.
The aim of this work is to evaluate and describe the current status of, and prospects for, the future of occupational hygiene in Finland. The main sources of information include a seminar held in the annual meeting of Finnish Occupational Hygiene Society and interviews with different stakeholders. Nanotechnology and other new materials, changing work environments, circular economy including green jobs, new medical methods and advances of construction methods were recognized as future challenges. Future work opportunities for occupational hygiene experts included exposure assessments in indoor air surveys, private consulting and entrepreneurship in general, international activities and product safety issues. Unclear topics needing more attention in the future were thought to be in new exposures, sensitive persons, combined effects, skin exposures and applicability of personal protective equipment. Occupational hygiene should broaden its view; occupational hygienists should have to cooperate with other specialists and grasp new challenges.  相似文献   

12.
13.
OBJECTIVE: This is a study of 8,464 adult women and 21,155 adult males who entered substance abuse treatment in Texas between 2000 and 2005. Participants were either on probation for driving under the influence (DUI), were referred to treatment by DUI probation, or had been arrested for DUI in the past year. METHODS: The female and male clients were compared on demographic characteristics, substance use patterns, DSM-IV diagnoses, and levels of impairment. T tests and chi square tests were used to determine significance and multivariate logistic regression identified predictors of completing treatment and being abstinent at follow-up. RESULTS: The proportion of females who were sent to treatment as a result of DUI increased from 27% in 2000 to 32% in 2005. Females were significantly more likely than males to be White (73% vs. 56%), to have used substances a shorter period of time (17 vs. 19 years), to be seeking custody to regain their children (11% vs. 2%), to meet the DSM criteria for drug dependence (32% vs. 23%), to have injected drugs (31% vs. 23%), to have used substances daily (42% vs. 40%), to have a depressive disorder (16% vs. 7%) or bipolar disorder (12% vs. 5%), and to be have been in treatment before (60% vs. 49%). In contrast, males were more likely to be alcohol dependent (49% vs. 44%). Females were less likely to complete treatment (67% vs. 72%) and reported significantly more days of problems on the 6 domains of the ASI at both admission and at 60-day follow-up. Furthermore, at follow-up, they were more likely to be living with someone who abused alcohol or used drugs (9% vs.7%). CONCLUSIONS: Although females comprised only 29% of the DUI treatment admissions, they were more impaired and experienced more problems than their male counterparts. The findings indicate that additional resources, including treatment for co-occurring mental health problems and living in sober households, may be keys to helping these women achieve abstinence and prevent additional DUI episodes.  相似文献   

14.
In the past, the chemical industry in Japan has been the cause of a number of major industrial accidents. Subsequent to each accident, specific lessons have been learned. These lessons learned have been implemented in terms of safety education of the employees and/or safety measures of the equipment and facilities resulting in a rapid decrease of corresponding accident frequencies. In this paper, we summarized both recent and past major accidents caused by chemical substances in fixed installations in Japan. Case studies show that runaway reactions are among the main causes of major accident occurrences in the chemical process industry in Japan. A recent fatal poisoning accident caused by H2S gas generated during maintenance work again highlights the necessity of adequate safety management in a chemical factory. Therefore, even if hazard evaluation of chemical substances and chemical processes is necessary to prevent runaway reactions, human error is also an important factor contributing to reaction hazards [Wakakura, M. (1997) Human factor in chemical accidents, J. Safety Eng. High Press. Gas. Safety Inst. Japan, 34, 846].  相似文献   

15.
从我国非煤矿山安全生产立法、安全生产管理体制、监察执法、群众监督、宣传教育、科研、矿山企业等方面与国外矿业进行了对比分析,分析了我国非煤矿山存在的问题以及与国外的差距,最后分析了产生问题与差距的原因。  相似文献   

16.
The aim of this study was to describe violence in Finnish workplaces by comparing it with leisure-time violence. The data were derived from 13,762 interviews made from a representative sample of the Finnish population in 1988. The subjects were asked to report all the violent incidents they had encountered during the previous 12 months. There were 394 victims of violence in workplaces, that is, 40.6 victims per 1,000 workers. The rate of occupational violence was almost identical for males (40.6) and females (40.5). The most hazardous occupations were prison guard, police officer, and mental health nurse. The main reasons for violence at work were related to refusal of an authority's order to go away or to the relationship between doctor or nurse and patient. A typical assailant was an unaccompanied man who was under the influence of alcohol.  相似文献   

17.
Objective: The purpose of this study was to identify and better understand the features of fatal injuries in cyclists aged 75 years and over involved in collisions with either hood- or van-type vehicles.

Methods: This study investigated the fatal injuries of cyclists aged 75 years old and over by analyzing accident data. We focused on the body regions to which the fatal injury occurred using vehicle–bicycle accident data from the Institute for Traffic Accident Research and Data Analysis (ITARDA) in Japan. Using data from 2009 to 2013, we examined the frequency of fatally injured body region by gender, age, and actual vehicle travel speed. We investigated any significant differences in distributions of fatal injuries by body region for cyclists aged 75 years and over using chi-square tests to compare with cyclists in other age groups. We also investigated the cause of fatal head injuries, such as impact with a road surface or vehicle.

Results: The results indicated that head injuries were the most common cause of fatalities among the study group. At low vehicle travel speeds for both hood- and van-type vehicles, fatalities were most likely to be the result of head impacts against the road surface.

The percentage of fatalities following hip injuries was significantly higher for cyclists aged 75 years and over than for those aged 65–74 or 13–59 in impacts with hood-type vehicles. It was also higher for women than men in the over-75 age group in impacts with these vehicles.

Conclusions: For cyclists aged 75 years and over, wearing a helmet may be helpful to prevent head injuries in vehicle-to-cyclist accidents. It may also be helpful to introduce some safety measures to prevent hip injuries, given the higher level of fatalities following hip injury among all cyclists aged 75 and over, particularly women.  相似文献   


18.
The first step to chart hazards in the working environment in Estonia (labour force: 0.65 million) was taken by the National Board of Health Protection in the beginning of 1996.

The existing chemical, physical, and biological agents in the working environment were investigated with the help of local health inspectors in all counties. An identification of hazards and workers at risk was carried out. The results of the analysis showed that 16% of Estonian industrial workers are exposed to different hazards: 20,000 persons are exposed to noise, 11,000 are working in the conditions of vibration, 10,000 are affected by unsatisfactory microclimate, 6,000 complain about long-lasting work in a compulsory posture, the overexertion of eyes is suffered by 5,500 persons, and physical overload by 3,500 workers. In the group of chemical hazards the greatest numbers of workers are exposed to organic dust (6,500) and welding aerosols (5,400), followed by petroleum products (2,700), and oil-shale dust (4,300). The measurements of working conditions showed that an average of 30.3% of the results are above the standards. Proposals for the improvement of the situation in occupational safety and health are presented.  相似文献   

19.
我国林区直升机吊桶灭火应用分析   总被引:1,自引:0,他引:1  
直升机吊桶灭火是一项成熟有效的航空森林消防技术,是国外林业发达国家的重要森林消防手段。我国经过多年的探索和实践,已经在多数重点林区推广应用并取得成效。分析了直升机吊桶灭火的特点、机型和设备,对吊桶灭火的方法进行了探讨。  相似文献   

20.
Introduction. The aim of this study was to evaluate the trend of occupational injuries in Turkey using epidemiologic criteria such as incidence mortality and fatality/all injuries recorded – rates. Materials and methods. Safety and health data were obtained from the Annual Statistic Books of the Social Insurance Institution (1988–2006) and Social Security Institution (2007–2011) of Turkey. Results. The results from the official data showed that although total employment is increasing the number of occupational injuries and incidence and mortality rates are decreasing. The results also demonstrate that occupational fatality/all injuries recorded – rate is increasing. The fatality/all injuries recorded – rate per 1000 injuries increased to 25.5 in 2011 from 8.6 in 1988. Each work day an average of five people died because of occupational injuries. Discussion and conclusions. The fatality/all injuries recorded – rate (the number of fatal cases per 1000 occupational injuries) is an important indicator of the injury rate for a country. Systems of occupational injury and illness surveillance constitute a critical resource for the management and reduction of occupational injuries and illness.  相似文献   

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