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301.
李胜超  刘明华  潘正现 《环境工程》2006,24(6):90-91,94
针对酒精废液的特点及目前浓缩燃烧处理技术存在的问题,提出了采用大流量、高流速、高真空的闪蒸浓缩技术和浓缩液分段喷入燃烧炉、分段燃烧方式来处理酒精废液,并采用U型飞灰沉降室来处理烟气以解决灰渣堵塞问题。工程实践结果表明,经浓缩燃烧处理后CODCr去除率能够达到99·96%,可以实现有机废水的零排放。  相似文献   
302.
介绍抚顺醇醚化学厂醇醚生产废水的排放与水质特点 ,结合工艺流程介绍处理工艺设计和技术参数。几年来的运行结果表明 ,采用生物滤池 生物接触氧化 纤维球过滤三级工艺处理醇醚表面活性剂废水 ,处理效果良好 ,出水CODCr<10 0mg/L ,SS <15mg/L ,滤后水可用于厂区绿化。  相似文献   
303.
Introduction: Driving under the influence (DUI) citations are still a serious concern among drivers aged 16–20 years and have been shown to be related to increased risk of fatal and nonfatal crashes. A battery of laws and policies has been enacted to address this concern. Though numerous studies have evaluated these policies, there is still a need for comprehensive policy evaluations that take into account a variety of contextual factors. Previous effort by this research team examined the impact of 20 minimum legal drinking age–21 laws in the state of California, as they impacted alcohol-related crash rates among drivers under 21 years of age while at the same time accounting for alcohol and gas taxes, unemployment rates, sex distribution among drivers, and sobriety checkpoints. The current research seeks to expand this evaluation to the county level (San Diego County). More specifically, we evaluate the impact of measures subject to county control such as retail beverage service (RBS) laws and social host (SH) laws, as well as media coverage, city employment, alcohol outlet density, number of sworn officers, alcohol consumption, and taxation policies, to determine the most effective point of intervention for communities seeking to reduce underage DUI citations.

Methods: Annual DUI citation data (2000 to 2013), RBS and SH policies, and city-wide demographic, economic, and environmental information were collected and applied to each of the 20 cities in San Diego County, California. A structural equation model was fit to estimate the relative contribution of the variables of interest to DUI citation rates.

Results: Alcohol consumption and alcohol outlet density both demonstrated a significant increase in DUI rates, whereas RBS laws, SH laws, alcohol tax rates, media clusters, gas tax rates, and unemployment rates demonstrated significant decreases in DUI rates.

Conclusions: At the county level, although RBS laws, SH laws, and media efforts were found to contribute to a significant reduction in DUI rates, the largest significant contributors to reducing DUI rates were alcohol and gas taxation rates. Policy makers interested in reducing DUI rates among teenagers should examine these variables within their specific communities and consider conducting community-specific research to determine the best way to do so. Future efforts should be made to develop models that represent specific communities who are interested in reducing DUI rates among drivers aged 16–20 years.  相似文献   

304.
采用混凝沉淀法对酒精废水进行深度处理实验及放大应用研究。结果表明,混凝剂种类、投加量、pH值及沉降时间对处理效果都起着重要作用。通过正交实验确定最优化组合,即聚合硫酸铝投加量为60mg/L,pH为8.0左右,沉降时间为90min条件下,废水COD去除率达41.91%;浊度去除率达46.15%;NH3-N去除率达49.61%。混凝沉淀法处理酒精废水可有效减轻后续膜处理工艺负荷,有助于提高回用水质。  相似文献   
305.
在EGSB反应器处理低质量浓度PVC离心母液废水的试验研究中,着重检测了反应器内颗粒污泥的性质及其活性影响因素,并用扫描电镜观测了颗粒污泥表面菌体分布情况.结果表明:反应器运行180 d后,当HRT为8 h时,EGSB反应器对PVC离心母液TOC去除率稳定在50%以上;EGSB反应器中颗粒污泥的形状、颜色、粒径分布、沉降速度、元素成分等方面都发生了变化;污泥最大比产甲烷活性为115 mL/(g·d);通过扫描电镜,在颗粒污泥表面观察到一些丝状菌和短杆菌等,但菌体密度不高;营养物质对颗粒污泥活性影响十分明显.   相似文献   
306.
A feasible and relatively readily available analytical method was adapted for the assessment of alcohol ethoxylates (AE) and fatty alcohols (FA) in sediments. This study illustrates the simultaneous measurement of 38 of 114 possible alcohol ethoxylate ethoxymers (AE) and fatty alcohols (FA) found in commercially important AE products. We predicted toxicity for all identified fractions, as well as the total mixture toxicity, relative to three exposure scenarios via sewage treatment plants (STP) for these widely used chemicals in consumer products and hence generate a preliminary environmental risk screening for AE and FA in sediments. The method is based on derivatization of solvent or solid-phase extracts with 2-fluoro-N-methylpyridinium p-toluenesulfonate (Pyr+). The derivatized extracts were analyzed with liquid chromatography/mass spectrometry (LC/MS) operating in the positive ion electrospray mode. The extraction efficiency of AE and FA in three different sediments of varying composition was evaluated with spike-recovery studies, ranging from 64% to 80%. The detection limits for individual ethoxymers typically ranged from 1 to 5ngg−1on a dry weight basis. The mean limit of detection (LOD) was 6ngg−1and the median LOD was 3ngg−1. AE and FA in sediments were found to be stable for two weeks if preserved with 3% (v/v) formalin and stored at 4–6C. Based on equilibrium partitioning, background concentrations of AE and FA were predicted to be below concentrations known to elicit chronically toxic effects. Total worst case mixture toxicities for all AE ethoxymers combined with FA were predicted to result in a risk quotient less than 0.6. Activated sludge treatment (STP) significantly reduced the release of total AE and FA by four-fold, suggesting that the total mixture risk quotient would be < 0.15 for sediment dependent organisms.  相似文献   
307.
The microbial immobilization method using polyvinyl alcohol(PVA)gel as an immobilizing material was improved and used for entrapment of activated sludge.The oxygen uptake rate(OUR)was used to characterize the biological activity of immobilized activated sludge.Three kinds of PVA-immobilized particles of activated sludge,that is,PVA-boric acid beads,PVA-sodium nitrate beads and PVA-orthophosphate beads were prepared,and their biological activity was compared by measuring the OUR value.The bioactivity of both autotrophic and heterotrophic microorganisms of activated sludge was determined using different synthetic wastewater media (containing 250 mg/L COD and 25 mg/L NH_4~ -N).The experimental results showed that the bioactivity and stability of the three kinds of immobilized activated sludge was greatly improved after activation.With respect of the bioactivity and the mechanical stability,the PVA-orthophosphate method may be a promising and economical technique for microbial immobilization.  相似文献   
308.
铁碳微电解预处理高浓度酒精废液   总被引:3,自引:0,他引:3  
采用废铁屑-焦碳组成微电解工艺预处理高浓度酒精废液。通过正交试验和单因素分析试验考察了反应时间、铁碳比、曝气强度对铁碳微电解工艺降解有机物,提高废水可生化性和pH的影响,最终确定了最佳反应条件。试验结果表明,反应时间、铁碳比和曝气强度对铁碳微电解处理酒精废液的影响程度依次降低,且最佳反应条件为反应时间2小时,铁水比125:500,曝气强度4m^3/m^2h,CODcr的去除率达到50%,废水的BOD5/CODcr值可由O.3提升到0.48,pH由3.5提高到5.2左右。作为高浓度酒精废液预处理工艺,铁碳微电解能够经济、有效降低后续处理工艺的负荷,提高废水的可生化性和碱度。  相似文献   
309.
This paper focuses on changing patterns of substance use among low income, African American drug users evacuated from New Orleans, Louisiana, during Hurricane Katrina of August 2005. It examines the relationship between increases and decreases in alcohol and tobacco (AT) use and illicit drug (ID) use after Katrina and pre‐disaster and within‐disaster factors. Data from structured interviews with 200 Katrina evacuees currently living in Houston were collected 8–14 months after the disaster. Multivariate analysis revealed that rises in AT use were positively associated with education. Females and younger evacuees were more likely to have increased AT use. ID use increase was positively associated with resource loss and leaving the city before Katrina. Decreases in AT and ID use were found to be associated with disaster‐related exposure. The paper discusses the specific consequences of disasters on disadvantaged minority substance users and the importance of developing public health disaster policies that target this population.  相似文献   
310.
应用分子拓扑理论预测卤代芳烃的正辛醇/水分配系数   总被引:5,自引:0,他引:5  
以分子拓扑理论为基础,提出了一个新的拓扑指数Y,并用Y研究了部分卤代芳烃的正辛醇/水分配系数KOW。研究表明,Y与卤代芳烃的正辛醇/水分配系数KOW的logKOW呈良好的线性关系,并给出了相关方程。新方法计算方便、精确度高、物理意义明确  相似文献   
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