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21.
吕春华  李亚峰  陈萍 《辽宁化工》2006,35(6):356-358,370
阐述了氨氮对垃圾渗滤液处理效果的影响,介绍了垃圾渗滤液中氨氮的脱除方法、技术特点及工作原理,结合国内外的工程实例,对各种处理技术进行了分析比较。  相似文献   
22.
韩宏亮 《化工时刊》2002,16(7):50-52
通过对液氨性质的分析,讨论了罐车设计和工作参数的确定过程,提出了液氨罐车装卸设计中的安全问题。  相似文献   
23.
The Fe/ZrO2 catalyst (1% Fe by weight) shows a strong adsorption capacity toward the nitric oxide (at room temperature the ratio NOFe is ca. 0.5) as a consequence of the formation of a highly dispersed iron phase after reduction at 500–773 K. Nitric oxide is adsorbed mainly as nitrosyl species on the reduced surface where the Fe2+ sites are prevailing, but it is easily oxidised by oxygen forming nitrito and nitrato species adsorbed on the support. However, in the presence of a reducing gas such as hydrogen, carbon monoxide, propane and ammonia at 473–573 K the Fe-nitrosyl species react producing nitrogen, nitrous oxide, carbon dioxide and water, as detected by FTIR and mass spectrometers. The results show that nitric oxide reduction is more facile with hydrogen containing molecules than with CO, probably due the co-operation of spillover effects. Experiments carried out with the same gases in the presence of oxygen show, however, a reduced dissociative activity of the surface iron sites toward the species NOχ formed by NO oxidation and therefore the reactivity is shifted to higher temperatures.  相似文献   
24.
A model (MAST) to calculate the mass flow of NH3 through amodel dairy farm has been developed. Updated emission factors for UKagriculturewere used to examine different abatement strategies available for a typicaldairy farm. A range of annual NH3 emissions was calculated for bothslurry and FYM based dairy systems. Emission for the slurry based system ranged between 27 kg NH3-N ha–1 yr–1, achieved using a combination of abatementstrategies, and 107 kg NH3-N ha–1 yr–1, calculated for a worst casescenario. For FYM, this range was between 33 and 86 kg NH3-Nha–1 yr–1. The greatest reductionswereachieved by manipulating options linked to fertiliser usage and manureapplication.  相似文献   
25.
Vanadium oxide spread highly on TiO2 (anatase, A) and SnO2, and rather densely on TiO2 (rutile, R) and ZrO2 to make the monolayer in less than 4–5 V nm−2. Profile of acid site of the monolayer was measured by temperature programmed desorption of ammonia, and its relation with the surface oxidation state was studied. The acid site density was high on the V2O5/TiO2 (A) independent of the degree of oxidation. On the other hand, that of V2O5/TiO2 (R) and V2O5/ZrO2 depended on the oxidation state, and the high value of the concentration was observed on the oxidized one. The strength of acid site generated on the V2O5 monolayer on TiO2 was as high as on the HZSM-5 zeolite. Turnover frequency (TOF) of propane conversion, and product selectivity were measured in propane oxidation. Among tested oxides, the V2O5/TiO2 (A) showed the high TOF and selectivity to form propylene, while those loaded on TiO2 (R) and ZrO2 the small TOF and poor selectivity. Therefore, the reaction profile of activity and selectivity could be related with the extent of spreading and solid acidity. An idea of limit of the acid site density ca. 1.5 nm−2 on the monolayer was elucidated.  相似文献   
26.
探索了氨合成催化剂还原后的温度对钝化操作与产品质量的影响,确定了最佳的钝化温度。  相似文献   
27.
通过模拟计算对深冷净化系统做了深入的分析,研究了深冷净化系统脱除甲烷化气中过量氮、甲烷、惰气和回收弛放气中氢的能力,甲烷化气组成和压力对净化效果和操作稳定性的影响。  相似文献   
28.
The catalytic filter, V2O5-WO3-TiO2 supported on a ceramic filter, is known as a promising material for treating particulates and NO x simultaneously at optimum temperatures around 320°C. In order to improve its catalytic activity at low temperatures, the effect of Pt addition on the catalytic filter has been investigated. Catalytic filters, Pt-V2O5-WO3-TiO2/SiC, were prepared by co-impregnation of Pt, V, and W precursors on TiO2 coated-SiC filter by vacuum aided-dip coating. The Pt-added catalytic filter shifted the optimum working temperature from 280–330°C (for the non Pt-impregnated filter) to 180–230°C, providing N x slip concentration less than 20 ppm for the treatment of 700 ppm NO at a face velocity of 2 cm/s with the same value over the non Pt-added catalytic filters. The promotional effect following the addition of Pt is believed to result from electrical modification of the catalyst maintaining a high electron transfer state. Ammonia oxidation was also observed to be dominant above the optimal temperature for SCR.  相似文献   
29.
二氧化碳激光熔铸技术在氨压缩机曲轴修复中的应用   总被引:3,自引:0,他引:3  
邢辉  张晓萍 《化工科技》2002,10(5):39-40
用连续输出功率在千瓦级的二氧化碳激光器 ,激光功率密度达到 (10 4~ 10 5)W·cm-2 时 ,对铁基材料表面进行熔铸 ,讨论了激光熔铸修复工艺 ,论述了对修复件强度、表面硬度和抗磨性能、残余应力的影响。  相似文献   
30.
本文介绍了用氨水作溶剂制取溴化锂的实验方法和生产工艺。通过正交实验确定了最佳工艺条件。从所用原料的价格和工艺操作角度来看,本文提出的方法优于其它方法。  相似文献   
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