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11.
船舶柴油机NOx后处理技术的进展   总被引:1,自引:0,他引:1  
根据国内外的降低NOx排放方面最新的成果和科研动态,主要介绍了当前正在研究或者已经应用于实际的有效降低柴油机NOx排放的技术措施,并分析了各种技术方法的特点和在实际应用过程中面临的问题。  相似文献   
12.
朱建林 《环境工程》2001,19(1):36-37
介绍一例窄小场地条件下柴油发电机噪声综合治理工程。通过对机房实行整体封闭隔声与吸声、以消声道兼作通风道强制通风、以消声器加垃圾道消除排气噪声等综合措施 ,使柴油发电机噪声完全达到标准。  相似文献   
13.
本文比较全面地阐述了近年来我国海洋环境保护工作所取得的主要成就,并针对未来沿海经济的迅速发展将给海洋环境带来的压力,探讨深入开展海洋环境保护工作。  相似文献   
14.
谢东海  韩奇  唐文浩 《环境科技》2005,18(Z1):10-12
海水养殖,特别是高位虾池养殖是近年来养殖业发展的新趋势,在其带来巨大经济效益的同时,也对周边生态环境带来巨大的威胁和破坏.为此,针对海水养殖对生态环境所带来的各种影响进行综述.  相似文献   
15.
In this study, the effects of a diesel oxidation catalyst (DOC) coupled with a catalyzed diesel particulate filter (CDPF) with different catalyst loadings on the power, fuel consumption, gaseous and particulate emissions from a non-road diesel engine were investigated. Results showed that the after-treatment had a negligible effect on the power and fuel consumption. The reduction effect of the DOC on the CO and hydrocarbon (HC) increased with the engine load. Further reductions occurred coupling with the CDPF. Increasing the catalyst loading resulted in a more significant reduction in the HC emissions than CO emissions. The DOC could increase the NO2 proportion to 37.9%, and more NO2 was produced when coupled with the CDPF below 250°C; above 250°C, more NO2 was consumed. The after-treatment could reduce more than 99% of the particle number (PN) and 98% of the particle mass (PM). Further reductions in the PN and PM occurred with a higher CDPF catalyst loading. The DOC had a better reduction effect on the nucleation particles than the accumulation ones, but the trend reversed with the CDPF. The DOC shifted the particle size distribution (PSD) to larger particles with an accumulation particle proportion increasing from 13% to 20%, and the geometric mean diameter (GMD) increased from 18.2 to 26.0 nm. The trend reversed with the CDPF and the accumulation particle proportion declined to less than 10%. A lower catalyst loading on the CDPF led to a higher proportion of nucleation particles and a smaller GMD.  相似文献   
16.
催化裂化废水连续萃取脱酚研究   总被引:2,自引:0,他引:2  
选用焦化粗柴油为萃取剂,在转盘萃取搭连续试验装置中,对催化裂化含酚废水进行脱酚预处理。结果表明,用焦化粗柴油做萃取剂,进水pH值为80~90不加调节;油水比(体积比)17∶1~21∶1;转盘转数1100r/min,酚萃取脱除率达到85%以上。萃取后的粗柴油依据现有工艺而进行加氢精制,不需进行再生等后处理。整个萃取工艺简单易行,能满足预处理的要求  相似文献   
17.
本文主要研究模糊控制技术在柴油发动机隔振系统中的应用,将模糊控制技术引入柴油发动机隔振主动控制系统,针对柴油发动机隔振模拟实验台架的振动特点,建立了控制系统数学模型,进行了柴油发动机隔振模拟实验台架垂直方向的仿真研究。  相似文献   
18.
研究了柴油机掺烧液化石油气(LPG)以降低黑烟排放的技术方案,并开发出了一种以独特型板调节装置为特征的机械控制式柴油/LPG双燃料供给系统。发动机不改变原有结构加装该系统后即成为柴油/LPG双燃料发动机,可以同时燃烧柴油和LPG两种燃料,并且在整个工作范围内,随着工况变化能够按照预先优化设定的型板型线规律而自动调节柴油/LPG供给量比例,使烟度降低50%以上,同时满足经济性、动力性以及操作性能等要求,此外,也可以切换为单独燃烧柴油,而不改变发动机的原有性能。该系统结构简单、成本低廉,非常适合于改装城市在用公交车,降低其黑烟排放。  相似文献   
19.
Understanding risks from the human-mediated spread of non-indigenous species (NIS) is a critical component of marine biosecurity management programmes. Recreational boating is well-recognised as a NIS pathway, especially at a regional scale. Assessment of risks from this pathway is therefore desirable for coastal environments where recreational boating occurs. However, formal or quantitative risk assessment for the recreational vessel pathway is often hampered by lack of data, hence often relies on expert opinion. The use of expert opinion itself is sometimes limited by its inherent vagueness, which can be an important source of uncertainty that reduces the validity and applicability of the assessment. Fuzzy logic, specifically interval type-2 fuzzy logic, is able to model and propagate this type of uncertainty, and is a useful technique in risk assessment where expert opinion is relied upon. The present paper describes the implementation of a NIS fuzzy expert system (FES) for assessing the risk of invasion in marine environments via recreational vessels. The FES was based on expert opinion gathered through systematic elicitation exercises, designed to acknowledge important uncertainty sources (e.g., underspecificity and ambiguity). The FES, using interval type-2 fuzzy logic, calculated an invasion risk value (integrating NIS infection and detection probabilities) for a range of invasion scenarios. These scenarios were defined by all possible combinations of two vessel types (moored and trailered), five vessel components (hull, deck, internal spaces, anchor, fishing gear), two infection modes (fouling, water/sediment retention) and six frequently visited marine habitats (marina, mooring, farm, ramp, wharf, anchorage). Although invasion risk values determined using the FES approach was scenario-specific, general patterns were identified. Moored vessels consistently showed higher invasion risk values than trailered vessels. Invasion risk values were higher for anchorages, moorings and wharves. Similarly, hull-fouling was revealed as the highest infection risk mode after pooling results across all habitats. The NIS fuzzy expert system presented here appears as a valuable prioritising and decision-making tool for NIS research, prevention and control activities. Its easy implementation and wide applicability should encourage the development and application of this type of system as an integral part of biosecurity, and other environmental management plans.  相似文献   
20.
基于重型底盘测功机,利用质子转移反应质谱(PTR-MS)研究了柴油公交车在中国典型城市公交车循环(CCBC)下,不同CDPF贵金属负载量对尾气中挥发性有机物(VOCs)组分排放特性的影响.结果表明,柴油公交车VOCs主要组分为含氧有机物(OVOCs)、芳香烃和烯烃等,且OVOCs占比达50%以上;在贵金属成分、配比相同时,VOCs减排率随CDPF贵金属负载量增加而增加:贵金属负载量为15 g·ft~(-3)(A型后处理装置)、25 g·ft~(-3)(B型)和35 g·ft~(-3)(C型)时,VOCs总量的减排率依次为36.2%、40.1%和41.4%.C型后处理装置对烷烃全循环减排率高达70.2%,且对OVOCs的催化有微弱优势;对于不饱和烃类,3种不同贵金属负载量的后处理装置均有一定催化效果,但无明显差异;A型对含氮有机物减排率可达50.5%,但减排率随贵金属负载量增加而降低.采用DOC+CDPF后能较好地降低公交车VOCs排放量进而降低臭氧生成潜势(OFP).同时考虑不同方案减排效果与成本因素,当加权系数分别为0.8和0.2时,B型为最优方案.  相似文献   
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