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171.
为处理低碳源生活污水,以内碳源反硝化途径为出发点,开发了后置缺氧UCT分段进水工艺.该工艺仅在UCT分段进水最后一好氧段末端增加了后置缺氧环节,以强化微生物内碳源储存能力.在低C/N水平(平均进水C/N=3.1±1.5)的生活污水条件下,后置缺氧UCT分段进水工艺实现了平均75.3%的TN去除率,运行61d后同步硝化反硝化去除的氮量高达31.5%;运行40d后污泥内碳源储存水平比原工艺污泥提高12.2%,9小时比内源反硝化速率由零提高至5.56mgN/(gVSS×d),系统可通过好氧段同步硝化内源反硝化(SNED)提高TN去除率.污泥沉降性能有明显改善:SVI值由350mL/g降至97mL/g,而原UCT分段进水工艺污泥仍然膨胀.该工艺仅在原工艺基础上增加了一后置缺氧段,无需外加碳源和额外硝化液回流设施,有利于水厂升级改造. 相似文献
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The optimum media height of carbon oxidation and nitrification in a down-flow biological aerated filter was determined, and the distribution of the heterotrophic and nitrifying populations through studying the changes of organic carbon contents and ammonia concentration at different media height was got. The results showed that as a down flow BAF with granular media, the active layer of nitrifiere was deeper than heterotrophs in BAF. And the optimum media height for the removal of SS, CODcr and NH4^+ -N was 40 cm,60cm and 80 cm respectively. The removal efficiency of SS, CODcr and NH4^+ -N was 79.1%, 63.9% and 96.4% respectively under theinfluent CODcr and NH4^+ -N of 122.1 mgCODcr/L and 14.84 mgNH4^+ -N/L, the influent flux of 15.8 L/h, air to liauid ratio of 3 : 1. 相似文献
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Biologically active carbon (BAC) system was set up in a water plant of South China during January to December 2007,to study the invertebrate community characteristics of BAC filter.Thirty-seven invertebrate species were found,of which 28 belonging to rotifers.Filter operation could lead to an output of invertebrates in high abundances with the filtrate,and the maximum density could reach 5608 individuals/m 3.Average abundances in the effluent water increased in 27-33 folds in comparison to the influent water during the sampling period.Invertebrate community succession had the following trend:filter-feeding animals → small benthic invertebrates → large benthic and resistant invertebrates.Abundances of large-sized invertebrates (copepod adult and oligochaete) at bigger-media column were significantly higher than that at small-media column.The results implied the abundant species diversity of invertebrate in BAC filter.The relationship between invertebrate and biofilm still remain to be studied in detail. 相似文献
178.
Zhihua Liu Asad Naeem Shah Yunshan Ge Yan Ding Jianwei Tan Lei Jiang Linxiao Yu Wei Zhao Chu Wang Tao Zeng 《环境科学学报(英文版)》2011,23(5):798-807
The effects of continuously regenerating diesel particulate filter (CRDPF) systems on regulated gaseous emissions, and number-size
distribution and mass of particles emanated from a diesel engine have been investigated in this study. Two CRDPF units (CRDPF-1
and CRDPF-2) with di erent specifications were separately retrofitted to the engine running with European steady-state cycle (ESC).
An electrical low pressure impactor (ELPI) was used for particle number-size distribution measurement and mass estimation. The
conversion/reduction rate (RCR) of hydrocarbons (HC) and carbon monoxide (CO) across CRDPF-1 was 83% and 96.3%, respectively.
Similarly, the RCR of HC and CO and across CRDPF-2 was 91.8% and 99.1%, respectively. The number concentration of particles
and their concentration peaks; nuclei mode, accumulation mode and total particles; and particle mass were highly reduced with the
CRDPF units. The nuclei mode particles at downstream of CRDPF-1 and CRDPF-2 decreased by 99.9% to 100% and 97.8% to 99.8%
respectively; and the particle mass reduced by 73% to 92.2% and 35.3% to 72.4%, respectively, depending on the engine conditions.
In addition, nuclei mode particles increased with the increasing of engine speed due to the heterogeneous nucleation initiated by the
higher exhaust temperature, while accumulation mode particles were higher at higher loads due to the decrease in the air-to-fuel ratio
(A/F) at higher loads. 相似文献
179.
随着人民生活水平的日益提高,对于生活环境的要求也越来越高,与之相反,随着工业文明的飞速发展,环境污染却日益加剧,水污染是环境污染的一大成因,如今,社会对于废水排放企业的关注和排污限制也越来越多,因此,废水经过深度处理,循环再利用,减少废水的排放及节约水资源是企业发展的必由之路。文章以上海申美饮料食品有限公司的废水深度处理与回用项目为案例,阐述曝气生物滤池+流砂过滤器处理饮料废水并回用的途径与办法。 相似文献
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本文介绍了长庆石化公司RO活性炭过滤器的基本原理,列出了设备检查和运行过程中常见的问题,并给予了解决方法,在启动前要检查填料和各阀门的开启情况,在运行过程中检查是否漏水,检查是否振动,检查各压力点以及正洗反洗时间。定期做好填料检查,孔密封垫检查,内部紧固件检查,内部清洗;对与常见问题也给予了解决方法。 相似文献