厌氧氨氧化颗粒污泥的培养及影响因素

在EGSB反应器中快速启动厌氧氨氧化(ANAMMOX)工艺,总氮去除速率为0.931±0.006 kg/(m~3·d),总氮去除效率为90.5%±0.8%。培养得到厌氧氨氧化颗粒污泥和絮状污泥混合物,污泥平均粒径为307.5μm。高质量浓度的NO_2~-(143.25 mg/L)抑制厌氧氨氧化菌活性;N_2H_4可强化厌氧氨氧化,但高质量浓度的N_2H_4抑制厌氧氨氧化菌活性;短期添加丙酸盐(COD质量浓度0~400 mg/L)对厌氧氨氧化速率几乎无影响;厌氧氨氧化速率随Fe~(3+)浓度(0~1.2 mmol/L)的增加而增加。     

铁碳微电解-微波强化Fenton联合工艺处理垃圾渗滤液膜滤浓缩液

利用铁碳微电解-微波强化Fenton联合工艺处理垃圾渗滤液膜滤浓缩液,探讨了微波功率、微波作用时间、H2O2投加量对微电解出水处理效果的影响。同时将铁碳微电解出水COD浓度、微波功率、微波作用时间、H2O2投加量对处理效果的影响建立了正交试验,结果表明:各因素对COD去除率影响的主次关系为:微电解出水COD微波功率H2O2投加量微波作用时间。     

高硫石油焦的脱硫研究

采用湿化学氧化和高温煅烧相结合的方法对含硫量6.28%(w)的石油焦进行二段脱硫处理,并利用FTIR、SEM和XRD技术对脱硫机理进行了探讨。实验结果表明:氧化工段的优化条件为硝酸与30%(w)双氧水的体积比1∶2、氧化时间10 h、氧化温度80℃、液固比35 m L/g、石油焦粒径106μm以下,优化条件下的氧化脱硫率为26.91%;煅烧工段的优化条件为1 280℃下煅烧6 h,优化条件下的煅烧脱硫率为79.43%,总脱硫率为83.95%。表征结果显示:经处理后石油焦中的黄铁矿类无机硫以及硫醇类和大部分噻吩类有机硫得到有效脱除,剩余噻吩硫转变为更稳定的形式;处理后的石油焦微观形貌轮廓变得清晰和圆润;处理前后石油焦的石墨雏晶结构基本未发生变化。     

粉末活性炭的Fenton氧化再生

采用Fenton氧化法对吸附处理染料废水后的饱和粉末活性炭(饱和炭)进行再生,考察了饱和炭的再生效果及其主要影响因素。实验结果表明:饱和炭的最佳再生条件为H2O2投加量6.5 mmol/g、再生p H 3.0、H2O2与Fe2+的摩尔比10、再生时间1 h;最佳条件下的再生率(再生粉末活性炭(再生炭)与新粉末活性炭对废水COD去除率的百分比)约为60%;使用最佳再生条件下得到的再生炭对废水进行吸附处理,废水的COD去除率和脱色率分别约为27%和67%。     

等离子喷涂制备 ZrB2-SiC 复合涂层及其静态烧蚀性能

目的提高C/C复合材料的抗静态烧蚀性能。方法利用大气等离子喷涂技术在C/C复合材料表面制备ZrB_2-SiC复合涂层,对其进行1500℃的静态烧蚀实验。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)及能谱分析仪(EDS)对涂层的物相成分、微观形貌等进行检测分析。结果采用大气等离子喷涂制备的ZrB_2-SiC涂层是由熔融的粉末粒子紧密堆积而成,呈现典型的层状结构,涂层均匀完整地覆盖于C/C基体表面,厚度约为200μm。涂覆有ZrB_2-SiC复合涂层的C/C复合材料试样在1500℃分别氧化2,3,4 h后,试样依旧保持完整,C/C基体未遭受损伤,试样的质量增加率依次为3.39%,2.95%,4.25%。结论采用大气等离子喷涂技术能够在C/C复合材料表面制备出厚度均匀、结构致密的ZrB_2-SiC复合涂层,ZrB_2-SiC复合涂层使C/C复合材料的抗静态烧蚀性能显著提高。     

中药废水处理工程应用研究

西安市某制药厂中药废水具有水量水质变化大,可生化性较差的特点.采用电解+水解酸化+ ABR厌氧+接触氧化+絮凝沉淀组合工艺对其进行处理;平均进水p(CODcr)=4 600 mg/L,平均出水p(CODcr)=42 mg/L,CODcr平均去除率为99.1％.实践结果表明,该工艺运行费用低,操作简便,易于维护,处理效果稳定,其出水各项指标均优于《黄河流域(陕西段)污水综合排放标准》(DB 61/224-2011)二级标准.     

连续型超临界水氧化系统出水酸碱性分流试验研究

在用连续型超临界水氧化设备处理废水时,经常发现系统的净化出水pH值变小、排盐出水pH值变大。为了深入研究并揭示其机理,选择原碱性废水中和水、原酸性废水中和水、弱碱性废水、NaCl水溶液、纯自来水和纯NaOH水溶液6种典型水样进行定量试验。结果表明,连续型超临界水氧化系统存在净化出水和排盐出水pH值变化的现象,即使废水在进入系统前调整为中性(pH=7),反应后依然是净化出水pH7,排盐出水pH7。该现象很可能是由于在超临界状态下原水中无机酸根离子和金属阳离子的结晶盐离解生成了H~+、OH~-,随后各自缔合成酸性和碱性物质。缔合的酸性物质留在超临界水中,并随之从净化水出口排出,降低了出水的pH值;缔合的碱性物质混入盐结晶析出物中,随之在亚临界区溶解并经过排盐口流出,而重新溶解的金属氢氧化物增加了排水的pH值。另外,在超临界水氧化反应器复杂的氧化腐蚀环境下也生成了一定量的OH~-和酸缔合物,它们对改变出水pH值有一定作用。酸根离子极难从超临界水氧化系统中分离,因此对碱性废水要慎重中和,特别要慎重选择酸根离子,最好不要用盐酸中和,这是因为其带入的Cl~-会引起超临界系统内的氯腐和系统净化出水口的酸腐。研究表明,因为存在出水pH值的变化,对超临界水氧化系统出水的纯净程度必须予以重新考虑。     

Scale Mismatches,Conservation Planning,and the Value of Social‐Network Analyses

Many of the challenges conservation professionals face can be framed as scale mismatches. The problem of scale mismatch occurs when the planning for and implementation of conservation actions is at a scale that does not reflect the scale of the conservation problem. The challenges in conservation planning related to scale mismatch include ecosystem or ecological process transcendence of governance boundaries; limited availability of fine‐resolution data; lack of operational capacity for implementation; lack of understanding of social‐ecological system components; threats to ecological diversity that operate at diverse spatial and temporal scales; mismatch between funding and the long‐term nature of ecological processes; rate of action implementation that does not reflect the rate of change of the ecological system; lack of appropriate indicators for monitoring activities; and occurrence of ecological change at scales smaller or larger than the scale of implementation or monitoring. Not recognizing and accounting for these challenges when planning for conservation can result in actions that do not address the multiscale nature of conservation problems and that do not achieve conservation objectives. Social networks link organizations and individuals across space and time and determine the scale of conservation actions; thus, an understanding of the social networks associated with conservation planning will help determine the potential for implementing conservation actions at the required scales. Social‐network analyses can be used to explore whether these networks constrain or enable key social processes and how multiple scales of action are linked. Results of network analyses can be used to mitigate scale mismatches in assessing, planning, implementing, and monitoring conservation projects. Discordancia de Escalas, Planificación de la Conservación y el Valor del Análisis de Redes Sociales     

Assessment of mutagenic potency of source water treated by ozone and adsorption processes

This research utilized the Ames test to determine the mutagenicity of water treated by advanced processes, including ozonation and granular activated carbon (GAC). Raw water samples for this research included those obtained from the Pan Hsin waterworks as well as samples containing humic acids. Treated samples were collected from the pilot‐scale advanced treatment plant. The Ames test was used to measure the mutagenicity of the water after each treatment process. For the Pan Hsin raw water samples treated with ozone or GAC, it was indicated that, regardless of whether samples were preozonated or not, they all showed a mutagenic potency less than 2 once the S9 enzyme was added. This level of mutagenicity is insignificant. The prepared humic acid samples, on the other hand, demonstrated a significant reduction in mutagenicity after the pre‐ozonation process, indicating that preozonation can lower the degree of mutagenicity. Furthermore, the mutagenicity of the prepared humic acid samples gradually decreased after the advanced treatment process. However, when chlorine was added later to these samples, the mutagenicity increased again. This research shows that the use of O3/GAC processes to treat water can successfully lower mutagenicity, indicating a great potential for applications in the treatment of drinking water.