Effect of bulk density of coking coal on swelling pressure

Coking coals are the important raw materials for the iron and steel industries and play an important role on its sustainable development, especially on the stamp-charging coke making with the characteristics of increasing the bulk density. There is a significance on the reasonable usage of the coking coal resource with the reduced production cost, improved efficiency of the economy to develop the stamp-charging coke making technology. Important effects of the density of coking coal on the coking and caking properties were investigated. In the article, the maximum values of swelling pressure and variation of Laowan gas coal and Xinjian 1/3 coking coal, Longhu fat coal and Didao coking coal, which were mined at Shenyang and Qitaihe respectively, were investigated under different bulk densities during the coking. The results showed that when the values of density increased from 0.85 ton/m³ to 1.05 ton/m³, for the Laowan gas coal, swelling pressure variation and even the maximum value changed slightly. The swelling pressure was 3.63 KPa when the density was improved to 1.05 ton/m³; for the Xinjian 1/3 coking coal, the values of swelling pressure changed significantly and the maximum values was 82.88 KPa with the density improved to 1.05 when the coal was heated to 600℃. The coke porosity, which was investigated by automatic microphotometer, decreased from 47.4% to 33.1% with the increasing of the density from 0.85 ton/m³ to 1.05 ton/m³, and the decreased value was 14.3%. Meanwhile, the pore structures of four cokes were characterized by an optical microscope.     

Effect of bulk density of coking coal on swelling pressure

Coking coals are the important raw materials for the iron and steel industries and play an important role on its sustainable development, especially on the stamp-charging coke making with the characteristics of increasing the bulk density. There is a significance on the reasonable usage of the coking coal resource with the reduced production cost, improved efficiency of the economy to develop the stamp-charging coke making technology. Important effects of the density of coking coal on the coking and caking properties were investigated. In the article, the maximum values of swelling pressure and variation of Laowan gas coal and Xinjian 1/3 coking coal, Longhu fat coal and Didao coking coal, which were mined at Shenyang and Qitaihe respectively, were investigated under different bulk densities during the coking. The results showed that when the values of density increased from 0.85 ton/m³ to 1.05 ton/m³, for the Laowan gas coal, swelling pressure variation and even the maximum value changed slightly. The swelling pressure was 3.63 KPa when the density was improved to 1.05 ton/m³; for the Xinjian 1/3 coking coal, the values of swelling pressure changed significantly and the maximum values was 82.88 KPa with the density improved to 1.05 when the coal was heated to 600°C. The coke porosity, which was investigated by automatic microphotometer, decreased from 47.4% to 33.1% with the increasing of the density from 0.85 ton/m³ to 1.05 ton/m³, and the decreased value was 14.3%. Meanwhile, the pore structures of four cokes were characterized by an optical microscope.     

羧甲基纤维素抑尘剂的制备及其应用研究

以羧甲基纤维素、丙烯酸丁酯、甲基丙烯酸甲酯为原料,用溶液聚合法制备出一种环保软膜抑尘剂.探讨了添加甘油、辛癸基葡糖苷对抑尘剂吸水性能、润湿性能的变化以及m(甘油):m(辛癸基葡糖苷)以不同配比加入抑尘剂后对粉尘含水率的影响.经傅里叶红外光谱、X-射线衍射仪、扫描电子显微镜、透射电子显微镜对制备的产物进行结构表征和形貌的分析.对抑尘剂的性能:耐风蚀性、温度适应性进行了测试.结果表明:当m(甘油):m(辛癸基葡糖苷)为2:3,室温时粉尘含水率达15.8%、50℃粉尘含水率仍可达11.7%;经3 h(15 m/s)风速吹扫,粉尘损失率仅为2.3%.     

应用CAMEO软件包预测聚合反应器丙烯泄漏影响范围

为了能够准确地预测聚合反应器发生泄漏时丙烯的扩散分布,提高应急救援工作效率,应用CAMEO软件包进行预测,通过该软件包中ALOHA、MARPLOT软件连用,解决了量化和图形显示问题。     

Performances of biological aerated filter employing hollow fiber membrane segments of surface-improved poly （sulfone） as biofilm carriers

Using the surface of poly （sulfone） hollow fiber membrane segments as grafted layer, the hydrophilic acrylamide chain was grafted on by UV-photoinduced grafting polymerization. The gained improvement of surface wettability for the modified membrane was tested by measuring the contact-angle as well as FTIR spectra. Then correlation between the hydrophilic ability of support material and the biofilm adherence ability was demonstrated by comparing the pollutant removal rates from urban wastewater via two identical lab-scale up-flow biological aerated filters, one employed the surface wettability modified poly （sulfone） hollow fiber membrane segment as biofilm carder and the other employed unmodified membrane segment as biofilm carder. The experimental results showed that under the conditions of influent flux 5 L/h, hydraulic retention time 9 h and gas to liquid ratio （G/L） 10： 1, the removal rates of chemical oxygen demand （COD） and ammonium nitrogen （NH4^＋-N） for the modified packing filter and the unmodified packing filter was averaged at 83.64% and 96.25%, respectively, with the former filter being 5%-20% more than the latter. The effluent concentration of COD, NH4^＋-N and turbidity for the modified packing filter was 25.25 mg/L, 2 mg/L and 8 NTU, respectively. Moreover, the ammonium nitrogen removal performance of the filter packing the modified PSF was compared with the other bioreactor packing of an efficient floating medium. The biomass test indicated that the modified membrane matrixes provided better specific adhesion （3310-5653 mg TSS/L support）, which gave a mean of 1000 mg TSS/L more than the unmodified membrane did. In addition, the phenomenon of simultaneous denitrification on the inner surface of the support and nitrification on the outer surface was found in this work.     

Effect of Sb dopant amount on the structure and electrocatalytic capability of Ti/Sb-SnO2 electrodes in the oxidation of 4-chlorophenol

Ti/Sb-SnO_2 anodes were prepared by thermal decomposition to examine the influence',of the amount of Sb dopant on the structure and electrocatalytic capability of the electrodes in the oxidation of 4-chlorophenol.The physicochemical properties of the Sb-SnO_2 coating were markedly influenced by different amounts of Sb dopant.The electrodes,which contained 5% Sb dopant in the coating, presented a much more homogenous surface and much smaller mud-cracks,compared with Ti/Sb-SnO_2 electrodes containing 10% or 15% Sb dopant,which exibited larger mud cracks and pores on the surface.However,the main microstructure remained unchanged with the addition of the Sb dopant.No new crystal phase was observed by X-ray diffraction(XRD).The electrochemical oxidation of 4-chlorophenol on the Ti/SnO_2 electrode with 5% Sb dopant was inclined to electrochemical combustion;while for those containing more Sb dopant,intermediate species were accumulated.The electrodes with 5% Sb dopant showed the highest efficiency in the bulk electrolysis of 4-chlorophenol at a current density of 20 mA/cm~2 for 180 min;and the removal rates of 4-chlorophenol and COD were 51.0% and 48.9%,respectively.     

Beijing Tong Ren Tang Company Limited Scientific Research Institute, Beijing 100011, China

By dynamic method under UV irradiation,commercial melt-blown polypropylene(PPMB)filter element was modified with acrylamide(AAm)using benzophenone(BP)as initiator.Attenuated total reflection-Fourier transform infrared spectroscopy and scanning electron microscope verified that polyacrylamide chain was grafted on the fiber surface of PPMB filter element.Elemental content analysis with energy dispersive X-ray of fibers revealed that the polymerization content in the inner part of filter element was relatively higher than that in the outer.Degree of grafting changed with initiator concentration,monomer concentration,reaction temperature and reached 2.6% at the reaction condition:C_(BP)=0.06 mol/L,C_(AAm)=2.0 mol/L,irradiation time:80 min,temperature: 60℃.Relative water flux altered with the hydrophilicity and pore size of filter element.In the antifouling test,the modified filter gave greater flux recovery(approximately 70%)after filtration of the water extract of Liuweidihuang,suggesting that the fouling layer was more easily reversible due to the hydrophilic nature of the modified filter.     

土壤容重改变对锌/镉超累积植物遏兰菜根系特征及吸镉的影响

为了探讨土壤容重的变化对锌/镉超累积植物遏兰菜(Thlaspi caerulescens)根系形态特征及吸收土壤中镉、锌的影响,采用土壤盆栽方法,研究了土壤结构改良剂(EB.a)对镉污染土壤(2.12 mg.kg-1)的容重和遏兰菜提取镉/锌效率的影响.EB.a用量分别为0、0.1%和2%,植物种植100 d后收获.结果表明,EB.a可有效地降低土壤容重,2%EB.a处理土壤容重从1.27g.cm-3降至1.09 g.cm-3;土壤容重的降低,促进了遏兰菜根系和地上部的生长;植物的总根长、根毛长、根冠比均显著提高(p0.05).随着植物根长的增加,遏兰菜地上部提取镉/锌总量均显著提高(p0.05).与对照相比,2%EB.a处理致使遏兰菜总根长增加了2.6倍,植物地上部镉浓度和提取总量分别提高了20%和30%,镉提取效率由15%提高至19%;但遏兰菜的地上部锌浓度和提取总量并没有显著变化.研究结果证实了改善土壤结构可以促进遏兰菜根系的生长从而提高植物对镉的提取效率.     

磁性离子印迹聚合物的制备及其对水中Pb(Ⅱ)的吸附

以铅离子为模板离子、乙二醇二甲基丙烯酸酯和偶氮二异丁腈为交联剂和引发剂、稀盐酸为洗脱剂,采用微波辅助反相乳液悬浮聚合法,制备了磁性离子印迹聚合物(MIIP),通过SEM、FTIR、XRD和BET技术对其进行了表征,并将其用于水中Pb(Ⅱ)的吸附.在初始质量浓度60 mg/L、溶液pH 6、吸附温度303 K、吸附时间6...     

重庆市汞污染的观测研究

为研究重庆市区汞污染状况，2004年9~11月，同步观测了重庆市近郊铁山坪小流域（TSP）和观音桥(GYQ)两个区域的全沉降、穿透水、地表径流和土壤中的总汞含量，估算了小流域中汞的输入输出通量，分析了城区和郊区的大气汞沉降和分布特征。结果表明，重庆已在一定程度上受到汞污染。在TSP，湿沉降是汞输入的主要方式，也就是说，在TSP，细颗粒是大气汞的主要来源，表层土则是大气汞的一个主要的汇。GYQ区域的汞污染比TSP相对严重。在GYQ，除了湿沉降以外，干沉降是汞来源的重要形式，表明在GYQ，粗颗粒可能对大气汞有很大的贡献。因此，本地源的排放对城区的影响比对郊区的影响大，尤其是城区火电站附近的土壤样品比郊区土壤的汞含量高很多，说明火电站是大气汞的重要来源之一。