盐度对好氧颗粒污泥硝化过程中N2O产生量的影响

采用好氧SBR反应器,考察盐度在0、5、10 g·L-1条件下好氧颗粒污泥全程硝化过程中N2O产生量的变化情况以及对系统脱氮效果的影响.结果显示,随着污水中盐度增加,N2O产生量呈递增趋势.在3个盐度下(0、5、10 g·L-1),溶解态N2O产生量分别为1.21、8.99、24.81 mg·m-3,释放态N2O产生量分别为0.95、3.46、16.45 mg·m-3.在盐度为5 g·L-1和10g·L-1条件下,N2O释放速率分别为0 g·L-1时的3.6倍和17.4倍.在3种盐度条件下无论是溶解态N2O还是释放态N2O产生量在硝化过程的变化趋势均是先上升后下降,且溶解态N2O产生量大于释放态产量.另外当盐度浓度较低时(低于5 g·L-1),对NH+4-N去除效果影响较小,NH+4-N的去除率与盐度为0 g·L-1时基本相同,均在98%以上;但当盐度升至10 g·L-1后,NH+4-N的去除率降到了70%.因此,污水中盐度增加不仅影响NH+4-N的去除效率,而且增加N2O产生量.     

限量曝气进水时间对硝化颗粒污泥的影响特性研究

缺氧-好氧环境的交替循环对氨氧化细菌和亚硝酸盐氧化细菌具有重要影响.本研究通过逐渐增加限量曝气进水时间(从10 min至120 min)延长缺氧时段,考察柱形SBR中硝化颗粒污泥对不同缺氧-好氧环境交替循环的响应特性.整个研究过程中,硝化颗粒污泥保持着稳定的颗粒特征,粒径大于0.8 mm的颗粒污泥占总污泥量的质量分数始终在95%以上,颗粒平均沉降速率维持在125～130 m·h-1之间.尽管缺氧时段不断延长,但NH+4-N去除率和NO-2-N累积率分别稳定在(60±5)%、(85±5)%;此外,在每个周期的曝气反应时段,NH+4-N的去除速率以及NO-2-N和NO-3-N的累积速率分别保持在90mg·(L·h)-1、70 mg·(L·h)-1和15 mg·(L·h)-1左右.以上结果表明,限量进水时间的延长及其所造成的不同时间跨度的缺氧环境对硝化颗粒污泥没有较为显著的影响.     

催化型连续再生颗粒捕集器对生物柴油发动机排放颗粒理化特性的影响

以某重型柴油机为原机,研究氧化催化转化器(Diesel Oxidation Catalyst,简称"DOC")与催化型颗粒捕集器(Catalyzed Diesel Particulate Filter,简称"CDPF")结合而成的催化型连续再生颗粒捕集器(Catalyzed Continuously Regeneration Trap,简称"CCRT")对燃用B20混合燃料柴油机颗粒排放理化特性的影响.试验结果表明:生物柴油发动机安装CCRT装置后排放的颗粒质量和数量均显著低于原机.CCRT装置对不同粒径颗粒的捕集效率不同,对聚集态颗粒的捕集效果略优于核态颗粒.与原机相比,安装CCRT后PAHs总排放量下降,在检测到的20种PAHs中有17种排放量减少.按环数比较,原机及安装CCRT装置后PAHs均以三环和四环为主.CCRT装置的安装使生物柴油发动机排放颗粒中化学成分毒性降低.     

Understanding the sources and composition of the incremental excess of fine particles across multiple sampling locations in one air shed

Well-designed health studies and the development of effective regulatory policies need to rely on an understanding of the incremental differences in particulate matter concentrations and their sources. Although only a limited number of studies have been conducted to examine spatial differences in sources to particulate matter within an air shed, routine monitoring data can be used to better understand these differences. Measurements from the US EPA Chemical Speciation Network （CSN） collected between 2002-2008 were analyzed to demonstrate the utility of regulatory data across three sites located within 100 km of each other. Trends in concentrations, source contribution, and incremental excesses across three sites were investigated using the Positive Matrix Factorization model. Similar yearly trends in chemical composition were observed across all sites, however, excesses of organic matter and elemental carbon were observed in the urban center that originated from local emissions of mobile sources and biomass buming. Secondary sulfate and secondary nitrate constituted over half of the PM2.5 with no spatial differences observed across sites. For these components, the excess of emissions from industrial sources could be directly quantified. This study demonstrates that CSN data from multiple sites can be successfully used to derive consistent source profiles and source contributions for regional pollution, and that CSN data can be used to quantify incremental differences in source contributions of across these sites. The analysis strategy can be used in other regions of the world to take advantage of existing ambient particulate matter monitoring data to better the understanding of spatial differences in source contributions within a given air shed.     

基于PM_(2.5)的气囊式隐形防尘鼻塞设计

最近环境恶化,雾霾天气比较严重,人们身心健康严重受到大气中粉尘的影响,而我们研发的隐形防尘鼻塞就可以很好地解决这一问题。防尘鼻塞外部由环形气囊包裹,环形气囊目的是将鼻塞固定在鼻孔里面;内部由外壳包裹的五层阻滤结构,分别为挡尘网、滤布层、两层泡沫过滤层、活性碳层、杀菌层。不同的粉尘环境条件,防尘鼻塞内部的阻滤结构及阻滤层厚度都有所不同。对PM2.5粉尘的过滤效率:标准要求>95%,实测>95.43%;气流阻力85 L/min,标准要求<343Pa,实测<276 Pa。该防尘鼻塞可以很好的解决因雾霾天气对人们造成的身心危害,同时更加适合排尘严重的企业工人佩戴。具有很好的开发生产应用价值和社会效益。     

Performance and microbial diversity of an expanded granular sludge bed reactor for high sulfate and nitrate waste brine treatment

The disposal of waste brines has become a major challenge that hinders the wide application of ion- exchange resins in the water industry in recent decades. In this study, high sulfate removal efficiency （80%-90%） was achieved at the influent sulfate concentration of 3600 mg/L and 3% NaC1 after 145 days in an expanded granular sludge bed （EGSB） reactor. Furthermore, the feasibility of treating synthetic waste brine containing high levels of sulfate and nitrate was investigated in a single EGSB reactor during an operation period of 261 days. The highest nitrate and sulfate loading rate reached 6.38 and 5.78 kg/（m3-day） at SO42--S/NO3-N mass ratio of 4/3, and the corresponding removal efficiency was 99.97% and 82.26% at 3% NaC1, respectively. Meanwhile, 454-pyrosequencing technology was used to analyze the bacterial diversity of the sludge on the 240th day for stable operation of phase X. Results showed that a total of 9194 sequences were obtained, which could be affiliated to 14 phyla, including Proteobacteria, Firmicutes, Chlorobi, Bacteroidetes, Synergistetes and so on. Proteobacteria （77.66%） was the dominant microbial population, followed by Firmicutes （12.23%） and Chlorobi （2.71%）.     

从分子质量的变化分析有机物对GAC吸附内分泌干扰物(BPA)的影响

从分子质量分布的角度研究了水中有机物对颗粒活性炭(GAC)吸附双酚A(BPA)容量及吸附速率的影响.结果表明,相对于以去离子水为本底的BPA溶液来说,GAC吸附以滤后水、臭氧后出水和原水为本底的BPA溶液的Langmuir模型的最大吸附容量q_m值分别下降了29.95%、43.56%和44.44%,而其拟二级动力学模型的k₂值分别下降了43.05%、49.75%和56.38%.相对分子质量3 000以上,尤其是10 000以上的有机物堵塞GAC的二级微孔;3 000以下,尤其是1 000以下的有机物与BPA分子之间存在直接的竞争吸附,是导致GAC对BPA的吸附容量以及吸附速率下降的主要原因.     

粉煤灰的矿物相态和颗粒组成分析：粉煤灰建筑砂浆的基础研究之二

利用粉晶Ｘ射线衍射，电子针和扫描电镜等现代分析技术，对南京５个电厂所排粉煤灰的微结构特征，如形貌，颗粒类型，矿物相种类等，进行了详细研究，从微观领域探讨了粉煤灰在砂浆掺合料中所起的作用，以及粉煤灰品质波动影响砂浆质量的内在原因。     

UASB—接触氧化法处理沤麻废水的研究

本试验采用ＵＡＳＢ—接触氧化工艺对沤麻废水的处理进行了研究，系统启动两个月后达到稳定的处理效果，厌氧段进水ＣＯＤ浓度为７００ｍｇ／１，有机负荷为９．２５ｋｇＣＯＤ／ｍ３·ｄ，停留时间为２４小时，ＣＯＤ去除率可达到８９．３％，好氧段接触氧化池的有机负荷为２．ＩｋｇＣＯＤ／ｍ３·ｄ，处理时间为１０小时，整个系统总的ＣＯＤ去除率可达到９７％，该工艺是处理高浓度沤麻废水行之有效的方法。     

UASB处理酒精废液颗粒污泥形成过程与运行效果的研究

本试验采中中温ＵＡＳＢ反应器处理酒精废液，通过启动、运行、颗粒污泥不同时期形成过程的探索，成功地培养出了颗粒污泥，取得了有机负荷高达１３－２２ｇＣＯＤ／ｌ．ｄ，ＨＲＴ１５．６－２２．３ｈｒ，ＣＯＤｃｒ去除率达８３．９－９２．２％，沼气产气率５．１－８．７１／ｌ．ｄ，ＣＨ４含量５５－７２％的良好效果。