A~2/O工艺内回流中溶解氧对反硝化的影响

溶解氧对微生物的生长影响很大,对A2/O工艺实际工程中缺氧反硝化、内回流中溶解氧对反硝化的影响进行分析,结果表明,在现行运行条件下,缺氧池反硝化不彻底,内回流液中溶解氧含量过高,是影响缺氧池反硝化的主要因子。硝化液回流中溶解氧在缺氧池去除的碳源量均值为137 kg/d,占到反硝化理论与实际消耗碳源差值量的69%。建议设置非曝气区,经过理论计算,可节约碳源0.58~3.46 mg/L,使缺氧池出水硝酸盐氮浓度降低0.1~0.73 mg/L。这不仅提高了脱氮的效率,还可以降低能耗。建议实施溶解氧自动控制,以减少能量消耗并提高脱氮效果。     

GPS在管线控制测量中的应用

对静态GPS在管线控制测量中的应用做了阐述,包括选点、数据采集和数据处理,结合GPS自带的后处理软件,以实例介绍了在数据处理中遇到的问题和解决方法.     

膨胀石墨除油机理及影响因素研究

针对水面浮油的去除问题,通过对新型吸附材料-膨胀石墨的扫描电镜观察,从其结构特征的角度揭示了膨胀石墨的吸油机理,首次系统地研究了温度、时间、pH等操作条件对吸附油性能的影响。扫描电镜的结果显示膨胀石墨的鳞片厚度都在100 nm以上,而且以大孔、超大孔为主,这种结构赋予了膨胀石墨独特的吸附特性。操作条件对膨胀石墨的吸附性能有重要的影响,在本实验条件下即在酸（中）性条件下,吸附时间1 min-2 min左右,转速为660 r/min膨胀石墨可达到饱和吸附量。     

Rehabilitation and improvement of Guilin urban water environment：Function-oriented management

Economic development and population growth have deeply damaged the urban water environment of Guilin City, China. Main problems involved structural damage and functional deterioration of the urban waters. An integrated technical scheme was developed to rehabilitate the urban water environment and to enhance the waters' functions during 1998-2008. Improvement of waters' functions included water system reconstruction, water pollution control, water safety assurance, and aquatic ecological restoration. The water system was reconstructed to connect different waters and clean water supplies to the lakes. Moreover, water pollution was controlled to improve water quality by endogenous pollutant elimination and extraneous pollutant interception. In addition, ecological measures put in place serve to enhance water system functions and better benefit both nature and humans. The project has brought about sound ecological, economic and social benefits in Guilin City, which can potentially be extended to similar cities.     

Mn/Fe-Mn改性HZSM-5在NH3-SCR中的催化性能

采用离子交换法制备了不同Mn含量及不同Fe/Mn物质的量比的HZSM-5改性分子筛,并以NH3为还原剂,在体积空速为12000 h-1条件下,考察了上述催化剂选择性催化还原NO性能.同时,运用环境扫描电镜(ESEM)、比表面积(BET)和X-射线衍射(XRD)等方法对催化剂进行了表征.结果表明,改性催化剂中活性组分在载体表面呈高度分散形式,催化活性较高,复合改性较单独改性性能更为优越,适量Fe的加入提高了催化剂催化活性和稳定性;(0.25)Fe-Mn/HZSM-5(Fe/Mn物质的量比为0.25)的NO转化率于300℃时最高达到98%,在300～500℃范围内NO转化率均保持在90%以上.实验还研究了不同焙烧温度下制备的(0.25)Fe-Mn/HZSM-5对NO转化率的影响.结果表明,焙烧温度对催化剂的活性影响较大,550℃为最佳焙烧温度.     

MBBR工艺中不同曝气方式充氧效率的比较及工程应用

通过设定不同的进水方式、曝气量、悬浮填料投加比,对比研究了MBBR工艺中三种曝气方式——均匀曝气、渐进曝气、单侧曝气的充氧效率,并且运用Matlab软件,采用非线性回归法计算测试条件下的饱和溶解氧浓度Cs和氧总传质系数KLα。得出:投加悬浮填料能明显提升原有曝气方式的充氧效率,但首先须保证填料在水中有一定活动强度,否则反会降低充氧效率;均匀曝气本身的充氧效率最佳,不过由于需要更大的气容比来带动填料运动,运行成本高于另外两种方式。     

Effect of lead on the sorption of 2,4,6-trichlorophenol on soil and peat

The effect of lead on the sorption of 2,4,6-trichlorophenol (2,4,6-TCP) on soil and peat was investigated using a batch equilibration method. Lead markedly diminished the sorption of 2,4,6-TCP, and 2,4,6-TCP had little effect on lead sorption. Peat was a more effective adsorbent for 2,4,6-TCP than soil. The desorption hysteresis of 2,4,6-TCP verified the presence of high-energy sorption sites. Mechanisms of lead suppression effect on the 2,4,6-TCP sorption included the following: Firstly, lead accelerated the aggregation of colloids, the aggregates covered the surface in part and shrunk the pore sizes of the adsorbents, hence decreased the sorption of 2,4,6-TCP. Secondly, X-ray absorption and Fourier transform infrared spectroscopy study suggested that lead competed with 2,4,6-TCP for carboxylic, phenolic and Si-OH groups of organic matter and clay minerals. Such competition was partly responsible for the overall suppression effect of lead on the sorption of 2,4,6-TCP.     

新型MnOx/CNTs催化剂低温选择性催化还原NO

采用等体积浸渍法制备了MnOx/CNTs催化剂,用于低温NH3选择性催化还原（SCR）NO的实验。使用BET,FT-IR,TEM和XRD对催化剂进行表征,结果表明：碳纳米管经混酸超声分散,增加了羧基活性基团,锰氧化物颗粒分布较均匀。在模拟烟气条件下,考察了催化剂的MnOx负载量、煅烧温度及质量和烟气流速比（W/F）对NO脱除率的影响。煅烧温度为773 K,MnOx负载量为10%时,NO脱除率达到98.56%;W/F为2-3 mg/（mL·min^-1）时NO的脱除率更高。     

活化粉煤灰的结构和组成研究

用化学分析、x光电子能谱、波谱、热谱和扫描电子显微镜等多种方法综合研究粉煤灰的体相和表面相的化学组成、颗粒形貌、表面价态、键型和表面相变过程等结构特征。发现粉煤灰的内部组成与表面组成明显不同;颗粒以微珠为主;粒度分布接近高斯分布;表面有Si－O－Si键,而无羟基;粉煤灰加热时有吸热和放热过程发生,并伴有失重现象。这些为粉煤灰的表面改性和综合利用提供了科学依据。     

Microalgae cultivation and culture medium recycling by a two-stage cultivation system

Nutrients and water play an important role in microalgae cultivation. Using wastewater as a culture medium is a promising alternative to recycle nutrients and water, and for further developing microalgae-based products. In the present study, two species of microalgae, Chlorella sp. (high ammonia nitrogen tolerance) and Spirulina platensis (S. platensis, high growth rate), were cultured by using poultry wastewater through a two-stage cultivation system for algal biomass production. Ultrafiltration (UF) or centrifuge was used to harvest Chlorella sp. from the first cultivation stage and to recycle culture medium for S. platensis growth in the second cultivation stage. Results showed the two-stage cultivation system produced high microalgae biomass including 0.39 g·L^–1Chlorella sp. and 3.45 g·L^–1S. platensis in the first-stage and second-stage, respectively. In addition, the removal efficiencies of NH₄⁺ reached 19% and almost 100% in the first and the second stage, respectively. Total phosphorus (TP) removal reached 17% and 83%, and total organic carbon (TOC) removal reached 55% and 72% in the first and the second stage, respectively. UF and centrifuge can recycle 96.8% and 100% water, respectively. This study provides a new method for the combined of pure microalgae cultivation and wastewater treatment with culture medium recycling.

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