pH和DO对好氧颗粒污泥去除高氨氮废水的影响研究

研究使用SBR成功培养的结构紧密、外形规则,具有良好脱氮性能的成熟好氧颗粒污泥处理高浓度氨氮废水,并探讨pH和DO对其处理效果的影响,旨在为工程实践提供理论依据。通过人工模拟废水,以蔗糖作为唯一碳源,NH4Cl为氮源,将进水NH4+-N浓度由300 mg/L逐步提高至900 mg/L,相应的NH4+-N负荷由0.6 kg/(m3.d)提高至1.8 kg/(m3.d),考察pH和DO对其处理效果的影响。研究结果表明:当控制反应器pH为8.0,曝气量为75 L/h时,好氧颗粒污泥脱氮的效果最好,氨氮去处率分别为96.70%9、2.33%。由于运行过程中每隔15 min监测每个反应器pH值,使其维持在各自pH值7.0±0.1范围内。这种酸碱度环境对异养菌等微生物并没有产生抑制作用;因此在各pH条件下,COD去除的所需时间和去除率基本没有差别。在不同的DO下,COD在初始的60 min里降解速度有明显区别。曝气量为150 L/h时,COD的降解速度最快,但是曝气量过大颗粒污泥内部厌氧区被压缩,因此选择最佳的曝气量为75 L/h。     

广西邦亮东黑冠长臂猿栖息地的气候资源分析

气候资源是影响动物行为、发育、存活、繁殖与分布等的重要因子。为了探明广西邦亮东黑冠长臂猿栖息地的气候环境特征,对其栖息地附近县(乡)的主要气象要素进行统计与分析。结果表明:广西邦亮东黑冠长臂猿栖息地年均日照时数为1 521.8小时,月变幅为25.44%;年均气温为19.1℃,最冷月平均气温为11.0℃,最热月平均气温为25.0℃;年均降雨量为1 606.3 mm,月变幅为86.05%;年均蒸发量为1 507.1 mm,月变幅为28.06%;年均相对湿度为80%,月变幅为2.60%;年均风速为1.5 m/s,月变幅为15.4%。     

河道溢油事故环境风险评价中若干关键问题探讨

河道溢油事故已成为内河道突发性水环境污染的主要问题之一,尤其水源地突发性污染事件日益增多,对社会、经济和河道生态环境造成严重的不良影响。新建的水上项目必须通过溢油风险评价来分析项目建设投产后对周边的环境影响,目前溢油风险评价尚无统一的方法,且风险分析不够深入。本文基于国内外经典的油膜动力学模型及统计学等理论,明确溢油事故环境风险评价中事故源强、事故概率、溢油油膜影响范围、风险应急时间以及水厂吸水口关闭时间等几个关键问题的分析方法,以期进一步提高河道溢油事故的环境风险评价水平。     

Characterization of chlorine dioxide as disinfectant for the removal of low concentration microcystins

Microcystins, which represents one kind of cancerogenic organic compounds, is abundant in eutrophication water. The effects of reaction factors on chlorine dioxide (ClO₂) for removal of low-concentration Microcystin-LR, Microcystin-RR, and Microcystin-YR in water as well as the reaction mechanisms was investigated by using enzyme-linked immunosorbent assay (ELISA) kit and gas chromatography-mass spectrometry (GC-MS). The results showed that MC-LR, MC-RR, and MC-YR could be efficiently decomposed by ClO₂. The degradation efficiency was shown positively correlated to the concentration of ClO₂ and reaction time; while the effect of reaction temperature and pH is slight. The kinetic constants and activation energies of the reaction of MC-LR, MC-RR, and MC-YR with ClO₂ are determined as 459.89, 583.15, 488.43 L·(mol·min)⁻¹ and 64.78, 53.01, 59.15 kJ·mol⁻¹, respectively. As indicated by high performance liquid chromatography mass spectrometer (HPLC-MS) analysis, degradation should be accomplished via destruction of Adda group by oxidation, with the formation of dihydroxy substituendums as end products. This study has provided a fundamental demonstration of ClO₂ serving as oxidizing disinfectant to eliminate microcystins from raw water source.     

废弃产品回收处理企业环境绩效评价初探

近年来,废弃产品回收处理行业日益受到政府和社会各界的关注,而回收处理企业是实施回收处理活动的主体,相关法律、法规的出台对回收处理企业提出了更高的要求。本文在概括梳理相关法律、法规的基础上,初步建立了废弃产品回收处理企业环境绩效评价指标体系,为回收处理企业采用先进的技术工艺、降低环境负荷、加强职业健康监护和企业环境管理提供参考,以适应国家政策要求和行业发展的需要。     

外加淀粉酶预处理污泥厌氧发酵产氢研究

通过外加淀粉酶预处理剩余污泥,考察了淀粉酶对污泥的破解效果,研究了接种产氢菌(Enterococcus sp.LG1)和未接种产氢菌两种状况下,污泥厌氧发酵产氢效果,并与相应温度(60℃)热预处理污泥的发酵产氢效果进行对比,同时分析探讨了污泥发酵产氢过程中底物和pH值的变化.结果表明,淀粉酶预处理污泥4h后水解效果最佳...     

己内酰胺生产废水的铁碳微电解深度处理与机理研究

采用铁碳微电解方法对己内酰胺生产废水进行深度处理,探讨了pH值、停留时间、铁碳质量比对处理效果的影响。在pH为4、停留时间为120 min、铁碳质量比为4的最佳处理条件下,COD去除率可达57.8%,色度去除率可达68.4%。微电解对己内酰胺废水的作用主要通过铁的絮凝作用,处理过程中的酸性条件、微电解的氧化还原和电场作用,从而提高其去除效率。     

220kV变压器噪声及其传播特性浅析

变压器噪声呈中低频特性,距离衰减率低,传播影响范围大。通过对上海某220kV露天变电站变压器噪声的实测数据进行简要分析,论述了220kV变压器噪声的强度及其频率特性,并探讨了变压器噪声在不同距离范围内的传播衰减特性。     

好氧颗粒污泥处理青霉素废水研究

青霉素在其生产过中产生大量的废水,其COD值较高,生化性较差,成分复杂,微生物难以降解,其处理技术是世界性难题。文章采用以葡萄糖模拟废水培养的好氧颗粒污泥为接种体,经青霉素废水逐步驯化后,使其完全处理青霉素废水。实验结果表明,应用好氧颗粒污泥技术,处理青霉素废水,COD,NH3_N,TP去除率较高,具有很好的处理效果。     

Aerobic granules cultivated and operated in continuous-flow bioreactor under particle-size selective pressure

A novel method based on the selective pressure of particle size （particle-size cultivation method, PSCM） was developed for the cultivation and operation of aerobic granular sludge in a continuous-flow reactor, and compared with the conventional method based on the selective pressure of settling velocity （settling-velocity cultivation method, SVCM）. Results indicated that aerobic granules could be cultivated in continuous operation mode by this developed method within 14 days. Although in the granulation process, under particle-size selective pressure, mixed liquor suspended solids （MLSS） in the reactor fluctuated greatly and filamentous bacteria dominated the sludge system during the initial operation days, no obvious difference in profile was found between the aerobic granules cultivated by PSCM and SVCM. Moreover, aerobic granules cultivated by PSCM presented larger diameter, lower water content and higher specific rates of nitrification, denitrifieation and phosphorus removal, but lower settling velocity. Under long term operation of more than 30 days, aerobic granules in the continuous-flow reactor could remain stable and obtain good chemical oxygen demand （COD）, NH4^＋-N, total nitrogen （TN） and total phosphorus （TP） removal. The results indicate that PSCM was dependent on the cultivation and maintenance of the stability of aerobic granules in continuous-flow bioreactors.