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141.
Wastewater treatment is one of critical issues faced by water utilities, and receives more and more attentions recently. The energy consumption modeling in biochemical wastewater treatment was investigated in the study via a general and robust approach based on Bayesian semi-parametric quantile regression. The dataset was derived from a municipal wastewater treatment plant, where the energy consumption of unit chemical oxygen demand (COD) reduction was the response variable of interest. Via the proposed approach, the comprehensive regression pictures of the energy consumption and truly influencing factors, i.e., the regression relationships at lower, median and higher energy consumption levels were characterized respectively. Meanwhile, the proposals for energy saving in different cases were also facilitated specifically. First, the lower level of energy consumption was closely associated with the temperature of influent wastewater, and the chroma-rich wastewater also showed helpful in the execution of energy saving. Second, at median energy consumption level, the COD-rich wastewater played a determinative role in the reduction of energy consumption, while the higher quality of treated water led to slightly energy intensive. Third, the higher level of energy consumption was most likely to be attributed to the relatively high temperature of wastewater and total nitrogen (TN)-rich wastewater, and both of the factors were preferably to be avoided to alleviate the burden of energy consumption. The study provided an efficient approach to controlling the energy consumption of wastewater treatment in the perspective of statistical regression modeling, and offered valuable suggestions for the future energy saving.  相似文献   
142.
随着挥发性有机物排污收费政策的逐步实施,快速准确地监测企业VOCs排放量已成为环保部门和企业共同面对的难题。介绍了开路式傅里叶变换红外光谱技术原理及优势,研究了质量通量模式VOCs排放量计算方法,并以300 m×300 m某装置区域为例,完成了现场红外光谱测量、气象数据采集、数据有效性分析和VOCs排放量计算。研究结果表明,开路红外光谱技术极大提高了VOCs排放数据采集效率和准确性,进一步计算得出该装置区域VOCs年排放量平均值为98.7 t,为企业开展VOCs排放量核算提供了参考。  相似文献   
143.
聚硅酸硫酸氯化铝铁絮凝剂的制备及絮凝性能   总被引:2,自引:1,他引:2  
以粉煤灰为原料制备了无机高分子絮凝剂聚硅酸硫酸氯化铝铁(PSiAFCS),用PSiAFCS处理以硅藻土为原料配制的模拟废水.实验结果表明,在n(Al3+):n(SO4-2)=11、PSiAFCS加入量为2.5mg/L、废水pH为6.0~11.0,温度为60℃、静置时间为20 min、废水初始浊度为50.00~500.00 NTU的范围内,PSiAFCS的絮凝效果良好,浊度去除率大于96%.PSiAFCS对赣江水的浊度去除效果优于聚硅酸氯化铝铁(PSiAFC)和聚合氯化铝(PAC).PSiAFCS加入量为2.5 mg/L时,水样的剩余浊度最低,为0.52 NTU,浊度去除率达98.27%,达到GB5749-2006<生活饮用水卫生标准>中浊度小于1.00 NTU的要求.  相似文献   
144.
长江水体氯化过程中强致突变物前驱物的筛选   总被引:8,自引:0,他引:8  
MX「3-氯-4-(二氯甲基)-5-羟基-2(5H)-呋喃酮」是饮用水液氯消毒中产生的一种具有强致突变性的副产物,利用一系列XAD吸附树脂和大孔离子交换树脂将长江水中的溶解态有机物分离为溶解态腐殖酸类,憎水弱酸类,憎水碱类,憎水中性物类,亲水酸类,亲水碱类6种组分,分别对不同组分的有机物进行氯化处理,用GC/MS选择离子峰面积法测定产物中的MX。  相似文献   
145.
应用鱼类生物完整性指数评价荔浦河河流健康   总被引:2,自引:0,他引:2  
生物完整性指数是河流生态系统健康评价主要方法之一。为评价荔浦河河流健康状况,选择鱼类作为指示生物,构建了基于鱼类生物完整性指标体系。2017年1月、4月、7月和10月对荔浦河4次采样共采集到鱼类21 192尾,经鉴定共计94种,隶属于6目17科62属。以S1(修仁镇)、S10(马岭镇)、S11(双江镇)作为参考点,经过分布范围分析、箱体图判别能力分析及相关性分析等指标筛选过程从25个候选指标筛选出5个指标,即鱼类总物种数、Shannon-Wiener多样性指数、肉食性鱼类数量百分比、敏感性鱼类数量百分比、产漂浮型卵鱼类数量百分比。将荔浦河河流健康等级分为"健康"、"一般"、"较差"、"极差"和"无鱼"5个等级。结果表明,荔浦河青山镇、荔浦县及蒲芦乡河段健康状态为"一般"水平,东昌镇、龙怀乡、杜莫镇及新坪镇河段健康状态为"较差"水平,茶城乡河段健康状态为"极差"水平。筑坝工程、架桥工程和修路工程等人类活动导致荔浦河支流上的健康状况比干流更差。上述研究结果可为荔浦河的河流管理和保护提供理论依据和技术支持。  相似文献   
146.
Water quality evaluation based on improved fuzzy matter-element method   总被引:1,自引:0,他引:1  
For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. The coefficient of variation of each indicator is used to determine the weight instead of traditional calculating superscales method. On the other hand, fuzzy matter-elements are constructed, and normal membership degrees are used instead of traditional trapezoidal ones. The composite fuzzy matter-elements with associated coefficient are constructed through associated transformation. The levels of natural water quality are determined according to the principle of maximum correlation. The improved fuzzy matter-element evaluation method is applied to evaluate water quality of the Luokou mainstream estuary at the first ten weeks in 2011 with the coefficient of variation method determining the weights. Water quality of Luokou mainstream estuary is dropping from level I to level II. The results of the improved evaluation method are basically the same as the official water quality. The variation coefficient method can reduce the workload, and overcome the adverse effects from abnormal values, compared with the traditional calculating superscales method. The results of improved fuzzy matter-element evaluation method are more credible than the ones of the traditional evaluation method. The improved evaluation method can use information of monitoring data more scientifically and comprehensively, and broaden a new evaluation method for water quality assessment.  相似文献   
147.
中国矿山环境治理恢复保证金制度   总被引:2,自引:0,他引:2  
由于中国当前的矿山环境保护政策尚不能从根本上解决矿山环境的主要问题,作为责任主体的矿山企业不能积极主动实施矿山环境治理与恢复。矿山环境治理恢复保证金是为了保证采矿权人履行矿山环境治理恢复义务而缴纳的资金。建立矿山环境治理恢复保证金制度就是为了贯彻"谁污染、谁治理;谁破坏,谁恢复"的环保原则,促进采矿权人在采矿过程中保护矿山环境,并确保在闭坑、停办、关闭后受破坏的矿山生态环境得到治理恢复的一项特别的经济手段和措施。实施保证金制度可以更好地促进矿产资源开发的外部成本内部化,是矿山环境保护必要且有效的形式。  相似文献   
148.
环境是人类生存的载体,是保证人类可持续发展的重要因素.因此,对环境中污染因子的监测也越来越重要.而生物监测是一种新型的监测技术,被认为是未来监测技术的重要方法,但由于其方法本身、技术的原因, 限制了其应用..随着水环境污染状况的日益加剧,对水体环境的监测以及水体安全的及时预警响应要求极为迫切,水环境生物监测是环境监测的重要内容.对生物监测技术在水环境中的应用进行了论述,并从技术、方法、应用等角度进行了具体分析,并对应用技术进行了总结.最后对生物监测技术的前景进行了展望.  相似文献   
149.
利用填埋层内生物代谢控制生活垃圾填埋场渗滤液污染   总被引:2,自引:0,他引:2  
讨论了目前国内卫生填埋场运行中存在的渗滤液问题 ,分析了不同填埋结构中生物代谢环境和主要污染物的代谢途径 ,探讨了不同填埋结构中利用渗滤液回灌来控制渗滤液污染的“生物反应器型”填埋技术。  相似文献   
150.

Currently, the correlation between ambient temperature and systemic lupus erythematosus (SLE) hospital admissions remains not determined. The aim of this study was to explore the correlation between ambient temperature and SLE hospital admissions in Hefei City, China. An ecological study design was adopted. Daily data on SLE hospital admissions in Hefei City, from January 1, 2007, to December 31, 2017, were obtained from the two largest tertiary hospitals in Hefei, and the daily meteorological data at the same period were retrieved from China Meteorological Data Network. The generalized additive model (GAM) combined with distributed lag nonlinear model (DLNM) with Poisson link was applied to evaluate the influence of ambient temperature on SLE hospital admissions after controlling for potential confounding factors, including seasonality, relative humidity, day of week, and long-term trend. There were 1658 SLE hospital admissions from 2007 to 2017, including 370 first admissions and 1192 re-admissions (there were 96 admissions with admission status not stated). No correlation was observed between ambient temperature and SLE first admissions, but a correlation was found between low ambient temperature and SLE re-admissions (RR: 2.53, 95% CI: 1.11, 5.77) (3.5 °C vs 21 °C). The effect of ambient temperature on SLE re-admissions remained for 2 weeks but disappeared in 3 weeks. Exposure to low ambient temperature may increase hospital re-admissions for SLE, and thus it is important for SLE patients to maintain a warm living environment and avoid exposure to lower ambient temperature.

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