A/O交替运行钢渣基复合滤料生物滤池处理模拟生活污水脱氮除磷特性

利用两级钢渣基复合滤料生物滤池(SSMBF)构建厌氧/好氧(A/O)交替运行工艺系统.在单池HRT=2h,A/O交替周期48h,厌氧DO=0.2~0.5mg/L,好氧DO=3~5mg/L,T=23~27℃的运行条件下,考察了SSMBF系统对模拟生活污水(pH=6.8~7.5,COD=260~330mg/L,NH4+-N=35~40mg/L,PO43--P=9~11mg/L)的处理效果,分析了其氨氮和磷去除特性.结果表明,两级A/O交替SSMBF系统具有良好的生活污水处理能力,对氨氮、磷和COD的去除率分别为95%、40%~60%和83.3%,出水氨氮、磷和COD浓度分别为0.5mg/L?3~6mg/L和50mg/L.在厌氧/好氧交替周期为48h的工况下,SSMBF系统的氨氧化菌和聚磷菌分别可在10h和8h恢复最佳活性.SEM?EDS表征和污染物去除特性分析结果显示,A/O交替运行SSMBF系统充分发挥了钢渣基复合滤料的离子和碱度释放特性,通过聚磷菌的厌氧释磷效应,在厌氧SSMBF中诱导促进了生物-结晶协同除磷,结晶产物为以羟基磷灰石为主的磷酸盐化合物.     

基于生态系统服务的生态承载力:概念、内涵与评估模型及应用

生态承载力是生态学研究的难点之一,是较资源承载力、环境承载力等更为复杂和综合的概念.论文在分析当前生态承载力研究进展的基础上提出以"生态系统—生态系统服务—人口和经济(承载力)"为研究主线的基于生态系统服务的生态承载力(Ecosystem-Servicesbased Ecological Carrying Capacity,ESECC)的定义,即某个区域生态系统的结构、过程及其空间格局决定的生态系统服务所能支撑的具有一定发展水平的人口和经济规模,并构建ESECC评估模型:将所有与人类密切相关的生态系统服务纳入评估模型,把生态系统和人类活动看作"黑箱",针对每种生态系统服务分别评估其承载力,并根据"短板效应"取最小值作为区域生态承载力.最后以全球重要农业文化遗产"云南红河哈尼稻作梯田系统"核心保护区之一云南省红河县为例对ESECC评估模型进行案例研究.     

嘉陵江出口段硅藻水华发生规律

嘉陵江是三峡库区最大支流,是重庆主城区重要的饮用水源,其主城段硅藻水华的发生预示着水质下降. 2005年8月—2008年3月连续对嘉陵江出口段水体水华硅藻密度进行监测并对数据进行分析. 结果表明:水华优势藻种为星肋小环藻(原变种)(Cyclotella asterocoststs),于每年的冬、春之交(1—3月)发生,生长速度快,发生数量有明显峰值并在总藻比例中绝对占优(0.02＜优势度＜0.28),4月以后水华现象消失直至次年同期再次发生,具有明显的年规律性. 水华发生时,污染物含量较高的磁器口右岸与朝天门右岸2个采样点的水华现象严重,尤其在2008年3月,磁器口右岸小环藻密度达到269×104 L-1,占同期总藻密度的92%. 较短的生活世代(5～7 d)使小环藻在适宜的生境中迅速增殖并在短期内迅速成为嘉陵江出口段富营养化敏感水体水华的优势藻种.      

组合MBR工艺中试系统处理高氨氮生活污水

以低碳氮比〔ρ(BOD₅)/ρ(TN)〕、高氨氮生活污水为研究对象,对强化缺氧/好氧+膜生物反应器(A/O+MBR)组合工艺系统的运行稳定性和处理效果进行中试研究.结果表明:在A/O工艺中引入纤毛填料,强化了组合工艺去除有机物及氨氮的效果,缓解了膜组件污染;根据进水负荷和温度变化,优化了工艺运行参数ρ(MLSS)和混合液回流比,系统稳定运行期间的HRT为6.7～11.9 h,膜通量为11～20 L/(m2·h);处理系统对BOD₅,COD_Cr,氨氮及SS的平均去除率分别达97.4%,87.2%,97.5%和100%,处理水ρ(BOD₅)≤ 6 mg/L,ρ(COD_Cr)≤ 40 mg/L,ρ(氨氮)≤5 mg/L;由于碳源缺乏,组合工艺对TN和TP去除率较低,分别为28.5%和26.8%,但处理水中的TN和TP以硝态氮和溶解性磷酸盐为主,是植物吸收氮源和磷源的主要形式,因此对符合再生水水源要求的处理水可作为城市绿化及农田灌溉用水回用,不仅可补充植物与作物生长必需的氮磷营养元素,而且为城市生活污水资源化提供了一条有效途径.      

沈阳北部城市污水处理厂设施运营对天津环保产业的几点启示

依据沈阳城市污水处理厂设施运营的经验,提出以城市污水处理厂建设为切入点,以排污制度为政策支柱,以重组环保产业集团为龙头,充分利用股票市场融资功能发展天津环保产业的模式。     

我国的固体废物管理研究

通过对 国固体废物的管理现状分析,对我国固体废物管理的出路进行了探讨。     

室内火灾条件下复合板装潢材料火灾特性的实验研究

运用ＩＳＯ Ｒｏｏｍ方法在全尺寸室内墙角火源条件下进行了复合板装潢材料火灾特性的研究,详细讨论了复合板的点燃,火焰传播和炭化物性以及室内火灾的发展过程。在墙角火源条件下,内火灾发展过程可分为四个不同阶段,而在每一发展阶段,东面和北面墙上复合板分别存在四个和三个明显不同的区域。当区域四内的复合板东面和北面墙上复合板分别存在四个和三个明显不同的区域。     

Optimizing biomass pathways to bioenergy and biochar application in electricity generation,biodiesel production,and biohydrogen production

The current energy crisis, depletion of fossil fuels, and global climate change have made it imperative to find alternative sources of energy that are both economically sustainable and environmentally friendly. Here we review various pathways for converting biomass into bioenergy and biochar and their applications in producing electricity, biodiesel, and biohydrogen. Biomass can be converted into biofuels using different methods, including biochemical and thermochemical conversion methods. Determining which approach is best relies on the type of biomass involved, the desired final product, and whether or not it is economically sustainable. Biochemical conversion methods are currently the most widely used for producing biofuels from biomass, accounting for approximately 80% of all biofuels produced worldwide. Ethanol and biodiesel are the most prevalent biofuels produced via biochemical conversion processes. Thermochemical conversion is less used than biochemical conversion, accounting for approximately 20% of biofuels produced worldwide. Bio-oil and syngas, commonly manufactured from wood chips, agricultural waste, and municipal solid waste, are the major biofuels produced by thermochemical conversion. Biofuels produced from biomass have the potential to displace up to 27% of the world's transportation fuel by 2050, which could result in a reduction in greenhouse gas emissions by up to 3.7 billion metric tons per year. Biochar from biomass can yield high biodiesel, ranging from 32.8% to 97.75%, and can also serve as an anode, cathode, and catalyst in microbial fuel cells with a maximum power density of 4346 mW/m². Biochar also plays a role in catalytic methane decomposition and dry methane reforming, with hydrogen conversion rates ranging from 13.4% to 95.7%. Biochar can also increase hydrogen yield by up to 220.3%.

     

Self-healing passivation of pyrite at ambient temperature

Environmental Chemistry Letters - Acid mine drainage is highly acidic and contains heavy metals, which can be harmful to soil, water, plants, and animals. To solve this issue, surface passivation...     

天然地质样品有机质组成对菲吸附-解吸的影响

以2种有机碳含量、结构和性质都相差较大的天然样品Chelsea土壤和Paxton页岩为吸附剂,以菲为吸附质进行一系列的吸附-解吸实验。结果显示,当土壤有机质是以腐殖酸为主时(Chelsea土壤),样品对疏水性有机化合物的吸附很容易达到平衡,解吸与吸附之间的滞后现象不是很明显。相反,对以干酪根为主要组成的Paxton页岩样品,吸附与解吸之间有明显滞后现象发生,吸附与解吸是一个完全不可逆过程。这说明土壤有机质组成和结构上的差异可能会成为决定有机污染物环境行为的主要因素。