Fabric-filter-supported catalyst for removal of harmful solid and gaseous compounds in municipal waste incinerator exhaust gas: characteristics of NO x reduction

We have investigated a fabric-filter-supported catalyst for removing harmful solid and gaseous compounds simultaneously from municipal incinerator exhaust gas. We studied the ways in which the efficiency of NO _x removal is influenced by filter temperature, gas flow rate, and catalyst content. The reduction of the catalyst content by mechanical reverse washing was investigated, and the state of the catalyst supported in the fabric filter was also observed using a scanning electron microscope. The catalyst supported by the fabric filter showed a removal efficiency above 75% when the filter temperature was 200°C, the gas flow rate was 1 m/min, and the catalyst content of the fabric filter was above 300 g/m². The catalyst was supported uniformly on the fibers of the fabric filter, and fine catalyst particles remained on the fibers after mechanical reverse washing. Received: October 15, 1997 / Accepted: March 19, 1999     

利用声凝聚机理提高喷雾降尘效果的研究

本文论述了利用声凝聚机理提高喷雾降尘效果,特别是对呼吸尘的降尘效果的研究过程。由该机理建立了声波频率和声强与降尘效果之间的数学模型。在此数学模型的基础上,开展了对声波发生器和声学喷嘴的研究。实验及使用结果表明,声学喷嘴可以显著提高对呼吸尘的降尘效果。     

吸附法处理含铬废水的研究

天然沸石、膨润土基材经镁铝等修饰并活化而制的ＦＭＡ，ＢＭＡ吸附剂处理含铬废水，铬的去除率可达９９％。     

人工湿地-氧化塘工艺组合对氮和磷去除效果研究

本文在小试规模上，研究了下行流湿地、推流床湿地、氧化塘和兼性塘四种处理单元的四种工艺组合对氮、磷的去除效果，研究结果表明：下行流湿地 氧化塘工艺组合具有较好的充氧效果，推流床湿地后置也可以提高出水的溶解氧。四种工艺组合对离子和TP、IP的去除无显著差异。人工湿地中硝化作用的发生有利于NH^ 4f-N的去除，增加氧化塘可以提高系统的硝化能力，但同时也会增加出水中的N0^-3-N浓度。     

LONG-TERM EQUILIBRIUM PHOSPHORUS CONCENTRATIONS IN THE EVERGLADES AS PREDICTED BY A VOLLENWEIDER-TYPE MODEL1

ABSTRACT: Anthropogenic phosphorus loading, mainly from the Everglades Agricultural Area (EAA), is believed to be the primary cause of eutrophication in the Everglades. The state of Florida has adopted a plan for addressing Everglades eutrophication problems by reducing anthropogenic phosphorus loads through the implementation of Best Management Practices (BMPs) in agricultural watersheds and the construction of stormwater treatment areas (STAs). Optimizing the effectiveness of these STAs for reducing phosphorus concentrations from agricultural runoff is a critical component of the District's comprehensive Everglades protection effort. Therefore, the objective of this study was to develop a simple tool that can be used to estimate STAs’performance and evaluate management alternatives considered in the Everglades restoration efforts. The model was tested at two south Florida wetland sites and then was used to simulate several management alternatives and predict ecosystem responses to reduced external phosphorus (P) loadings. Good agreement between model predictions at the two wetland sites and actual observations indicated that the model can be used as a management tool to predict wetlands’response to reductions in external phosphorus load and long-term P levels in aquatic ecosystems. Model results showed that lowering P content of the Everglades Protection Area (EPA) depends on reducing P loads originating from EAA discharges, not from rainfall. Assuming no action is taken (e.g., no BMPs or STAs implemented), the steady state model predicted that the average concentration within the modeled area of the marsh would reach 20 μg L^?1 within five years. With an 85 percent reduction in P loading, the steady-state model predicted that Water Conservation Area 2A (WCA-2A) P concentration will equilibrate at approximately 10 μ L^?1, while elimination of all loadings is projected to further reduce marsh P to values less than 10 μg L^?1.     

改性氢氧化钙粉体的研制及其特性

介绍了作为氯气清除剂的粉体应具有的特性,并对粉体的研制方法进行了简单叙述。同时,对改性氢氧化钙粉体特性作了详细介绍。不难看出,研制的改性氢氧化钙粉体具有高度活性,与氯气捕消器配合使用,将成为氯气泄漏时的抢险措施     

磨料水射流除鳞技术在钢厂的应用

为了暴露各种钢材在热轧过程中产生的表面缺陷，需清除附于其上的氧化铁皮，称之为“除鳞”。传统的除鳞方法有酸洗、表面剥皮、喷丸处理等，这些方法存在很多缺点。本文介绍已在湖南涟钢用于生产的磨料水射流除鳞生产线，用磨料水射流除鳞具有速度快、质量高、成本低、操作简便等独特的优点。     

皂化废水的资源化治理技术

采用预处理后与锅炉烟气联合治理，废水循环回用的工艺治理高浓度碱性皂化废水，使皂化废水作为一项资源得到了充分的利用，取得了较好的环境和经济效益。     

污水处理过程中聚糖菌的富集培养

研究了通过磷限制条件来达到聚糖菌的选择与富集,同时在驯化过程中还观察到,在第一阶段培养过程中,对除磷效果乙酸比丙酸更加有效。     

Long- and short-chain AHLs affect AOA and AOB microbial community composition and ammonia oxidation rate in activated sludge

Quorum sensing (QS) regulation of the composition of ammonia-oxidising archaea (AOA) and ammonia-oxidising bacteria (AOB) communities and functions in wastewater treatment was investigated. Specifically, we explored the role of N-acyl-l-homoserine lactones (AHLs) in microbial community dynamics in activated sludge. On average, the specific ammonia-oxidising-rate increased from 1.6 to 2.8?mg?NH₄⁺-N/g?MLSS/hr after treatment with long-chain AHLs for 16?days, and the addition of AHLs to sludge resulted in an increased number of AOA/AOB amoA genes. Significant differences were observed in the AOA communities of control and AHL-treated cultures, but not the AOB community. Furthermore, the dominant functional AOA strains of the Crenarchaeota altered their ecological niche in response to AHL addition. These results provide evidence that AHLs play an important role in mediating AOA/AOB microbial community parameters and demonstrate the potential for application of QS to the regulation of nitrogen compound metabolism in wastewater treatment.