化学循环燃烧载氧体的研究进展

化学循环燃烧是集分离捕集CO2和去除NOx为一体的新型燃烧技术。介绍了化学循环燃烧的发展背景、工艺原理及特点;综述了化学循环燃烧载氧体的选材、载氧体的性能要求,对各系载氧体（如NiO系、Fe2O3系、CuO系、CoO系和Mn2O3系载氧体）的性能进行了对比分析;提出了Fe2O3、Fe2O3／Al2O3（质量分数为60％的Fe2O3＋质量分数为40％的Al2O3）、NiO／NiAl2O3（质量分数为50％的活性NiO＋质量分数为50％的NiAl2O3）是当前的优势载氧体,并对载氧体的发展做了展望。     

悬浮生物膜载体强化氨氮降解研究

为了缩短氨氮降解时间,提高氨氮转移速率,利用新型悬浮载体对氨氮降解进行了研究.将生物膜培养分成3个阶段,每个阶段采用不同的运行条件,提高了膜上硝化菌的附着量,在载体上培养形成了以丝状细菌为附着体的蜂窝状微生物薄膜,增加了微生物附着的比表面积,薄膜的形成有利于氧气的扩散和基质的转移,为硝化菌提供了有利的生存环境.试验在pH值7.8～8.2,温度为24～29℃的条件下,在曝气90min时,氨氮从78 mg/L降解到2 mg/L以下,COD从140～300 mg/L降解到50mg/L以下;在曝气180min时,氨氮浓度从80～130 mg/L降解到3.5 mg/L以下,COD浓度从150～350 mg/L降解到46 mg/L以下.试验实现了同步去除COD和氨氮,与传统的活性污泥法相比,缩短了氨氮的降解时间,提高了氨氮降解速度.从微生物学和动力学理论对悬浮生物膜载体高效的氨氮降解和硝化机理进行了分析.     

生物过滤除臭填料挂膜驯化试验研究

将填料装入生物滤塔之前,对其进行挂膜驯化培养,待其成功后即可装填使用。试验结果表明,第12d后,发现树皮表面长有生物膜。在没有营养盐供应的情况下,微生物依然可以利用有机填料作为碳源进行代谢反应。42d后,从生物膜的镜检和混合液的pH值变化可知,用于除臭的优势微生物驯化成功。     

EFFECT OF FLOW VELOCITY ON SEDIMENT OXYGEN DEMAND: COMPARISON OF THEORY AND EXPERIMENTS1

ABSTRACT: Theoretical equations that establish the relationship between sediment oxygen demand (SOD) in a lake and the flow velocity and dissolved oxygen concentration in the bulk water already exist. These theoretical equations for oxygen consumption in the sediment express biological consumption with Michaelis-Menten kinetics, and chemical consumption by a first order reaction. Data from laboratory experiments that were conducted to validate the theoretical equations also exist. These experiments were performed in a laboratory channel with well defined flow characteristics for three types of sediments. Herein, the theoretical equations are used to model the experimental data for the three types of sediments. The values used for the parameters in the theoretical equations are determined by iteration until a best fit is obtained for the relationship of SOD to flow velocity from both the theoretical model and experimental data. The goodness of fit is measured by the standard error of prediction and the regression coefficient.     

缺氧池填料投配比对A~2/O-MBR工艺反硝化除磷的影响

按20%的投配比往好氧1,2池中加入相同数量的悬浮式填料,将传统A2/O工艺转变为A2/O-MBR复合工艺。通过处理实际市政污水,重点考察了在缺氧池中不同填料投配比条件下,复合工艺的去除效果以及反硝化除磷效果。实验结果表明,当缺氧池中填料投配比为20%时,装置总体的处理效果最好。COD、总氮、氨氮和总磷的去除率分别达到了81.1%、80.3%、100%和85.2%。当投配比为10%时,反硝化除磷效果最明显,占总除磷量的48.3%。从经济角度出发,10%的投配比为最佳投配比。     

普通话与口才训练教学中应加强人文素质教育

经济社会的飞速发展并没有带来人文精神的匹配升华,新生代大学生无法和社会历史融合最重要的原因就是人文素质教育的缺乏。应使普通话与口才训练成为大学生人文素质教育的有效载体和实践途径,输送给学生口语交际知识和人文素质的双重养分。     

Improving Oxygen Conditions in the Deeper Parts of Bornholm Sea by Pumped Injection of Winter Water

Vertical diffusivity and oxygen consumption in the basin water, the water below the sill level at about 59 m depth, have been estimated by applying budget methods to monitoring data from hydrographical stations BY4 and BY5 for periods without water renewal. From the vertical diffusivity, the mean rate of work against the buoyancy forces below 65 m depth is estimated to about 0.10 mW m⁻². This is slightly higher than published values for East Gotland Sea. The horizontally averaged vertical diffusivity κ can be approximated by the expression κ = a₀N⁻¹ where N is the buoyancy frequency and a₀ ≈ 1.25 × 10⁻⁷ m² s⁻², which is similar to values for a₀ used for depths below the halocline in Baltic proper circulation models for long-term simulations. The contemporary mean rate of oxygen consumption in the basin water is about 75 g O₂ m⁻² year⁻¹, which corresponds to an oxidation of 28 g C m⁻² year⁻¹. The oxygen consumption in the Bornholm Basin doubled from the 1970s to the 2000s, which qualitatively explains the observed increasing frequency and vertical extent of anoxia and hypoxia in the basin water in records from the end of the 1950s to present time. A horizontally averaged vertical advection–diffusion model of the basin water is used to calculate the effects on stratification and oxygen concentration by a forced pump-driven vertical convection. It is shown that the residence time of the basin water may be reduced by pumping down and mixing the so-called winter water into the deepwater. With the present rate of oxygen consumption, a pumped flux of about 25 km³ year⁻¹ would be sufficient to keep the oxygen concentration in the deepwater above 2 mL O₂ L⁻¹.     

阿特拉津土壤污染修复菌剂载体材料的筛选与应用

阿特拉津是长残留除草剂,其环境行为和生物修复技术已成为有机污染控制领域的研究热点。以廉价的高岭土、凹凸棒土和腐殖酸为载体材料,采用正交实验,把功能菌存活率作为目标性状,参考材料成球率,筛选出性能较好的高岭土、凹凸棒土和腐殖酸质量配比3种,分别为1∶0.5∶0.5(A3B2C1)、0.5∶0∶0.5(A2B3C1)和1∶0∶1(A3B1C2);在温度和紫外线耐受力实验中,A3B2C1材料配比更能够有效提升功能菌在高温和紫外线作用下的存活率,即载体中高岭土、凹凸棒土和腐殖酸质量比为1∶0.5∶0.5时效果最佳;利用A3B2C1载体材料配比制备菌剂,进行室内土壤修复实验,35 d时0.1%和0.5%载体菌剂添加量修复土壤中阿特拉津完全降解,而2个游离菌修复土壤中残留率均16%,0.1%载体菌剂添加量修复过程中土壤微生物Shannon多样性指数和均匀度变化幅度较其他修复方式小,有利于土壤微生物生态系统的平衡,因此0.1%载体菌剂添加量修复效果为最优。     

Modelling geochemical and microbial consumption of dissolved oxygen after backfilling a high level radiactive waste repository

Dissolved oxygen (DO) left in the voids of buffer and backfill materials of a deep geological high level radioactive waste (HLW) repository could cause canister corrosion. Available data from laboratory and in situ experiments indicate that microbes play a substantial role in controlling redox conditions near a HLW repository. This paper presents the application of a coupled hydro-bio-geochemical model to evaluate geochemical and microbial consumption of DO in bentonite porewater after backfilling of a HLW repository designed according to the Swedish reference concept. In addition to geochemical reactions, the model accounts for dissolved organic carbon (DOC) respiration and methane oxidation. Parameters for microbial processes were derived from calibration of the REX in situ experiment carried out at the Asp? underground laboratory. The role of geochemical and microbial processes in consuming DO is evaluated for several scenarios. Numerical results show that both geochemical and microbial processes are relevant for DO consumption. However, the time needed to consume the DO trapped in the bentonite buffer decreases dramatically from several hundreds of years when only geochemical processes are considered to a few weeks when both geochemical reactions and microbially-mediated DOC respiration and methane oxidation are taken into account simultaneously.     

移动床生物膜反应器在污水处理中的应用研究

应用好氧移动床生物膜反应器处理生活污水,厌氧复合生物反应器处理高浓度有机废水,厌氧－好氧移动床生物膜工艺处理食品废水的试验均取得良好的效果。试验结果表明,该工艺具有处理效率高,出水水质稳定,耐冲击负荷能力强,占地少,结构紧凑,维护管理简单的特点。