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901.
902.
Jinfeng Bai Chunwang Yang Zhenning Zhao Xiangyun Zhong Yaru Zhang Jun Xu Bai Xi Hongchun Liu 《环境科学学报(英文版)》2013,(S1):S205-S209
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. 相似文献
903.
Zhenning Zhao Jinfeng Bai Jun Xu Yaru Zhang Xiangyun Zhong Hongchun Liu Dekai Yang 《环境科学学报(英文版)》2013
Long flame coal are abundant and widely distributed in China, but the resource utilization is quite low, the production efficiency is not high. Stamp-charging coke making technology can bend some long flame coal, which can reduce production cost and expand the coking coal resources. The long flame coal of different mass fraction is added into prime coking coal including fat coal from Longhu, 1/3 coking coal from Xinjian and coking coal from Didao in experiment. The swelling pressure is tested on-line detection using pressure sensor in coke making process, and the pores are observed by scanning electron microscopy. The results show that, the swelling pressure first increase and then decrease with the temperature increased and the maximum swelling pressure reduces gradually with mass fraction of the Long flame coal from Shenmu increased in coke making process. The SEM images of resultant coke display that the coke get more and more loose and the amount of pores is increased with mass fraction of the long flame coal from Shenmu increased. The amount pores and the pore diameter both is minimum for coking coal from Didao as prime coking coal under the same fraction of long flame coal. 相似文献
904.
Jinfeng Bai Chunwang Yang Zhenning Zhao Xiangyun Zhong Yaru Zhang Jun Xu Bai Xi Hongchun Liu 《环境科学学报(英文版)》2013
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. 相似文献
905.
906.
对辽宁省鞍山市某生活垃圾卫生填埋场的晚期垃圾渗滤液进行预处理,选择MgO和磷矿粉两种矿物,利用共沉淀法去除垃圾渗滤液中的氨氮,用于制备磷铵镁复合肥,实现垃圾渗滤液的资源化利用。实验结果如下:MgO与磷矿粉配合使用,能够较好地去除垃圾渗滤液中COD和氨氮。采用MgO、磷矿粉共沉淀法生成磷铵镁复合肥具有可行性,同时可为后续生化处理创造良好的条件;在给定条件下(氨氮浓度1200 mg/L,COD 3180 mg/L),垃圾渗滤液COD去除的最优实验条件为MgO添加量5.0 g/L、磷矿粉添加量100 g/L,反应时间4 h,处理后COD去除率为62.1%,氨氮去除率为87.5%;氨氮去除的最优实验条件为MgO添加量10 g/L、磷矿粉添加量60 g/L、反应时间4 h,处理后COD去除率为42.1%,氨氮去除率为96.1%。 相似文献
907.
Mercury transportation in soil via using gypsum from flue gas desulfurization unit in coal-fired power plant 总被引:1,自引:0,他引:1
The mercury flux in soils was investigated, which were amended by gypsums from flue gas desulphurization (FGD) units of coal- fired power plants. Studies have been carried out in confined greenhouses using FGD gypsum treated soils. Major research focus is uptakes of mercury by plants, and emission of mercury into the atmosphere under varying application rates of FGD gypsum, simulating rainfall irrigations, soils, and plants types. Higher FGD gypsum application rates generally led to higher mercury concentrations in the soils, the increased mercury emissions into the atmosphere, and the increased mercury contents in plants (especially in roots and leaves). Soil properties and plant species can play important roles in mercury transports. Some plants, such as tall fescue, were able to prevent mercury from atmospheric emission and infiltration in the soil. Mercury concentration in the stem of plants was found to be increased and then leveled off upon increasing FGD gypsum application. However, mercury in roots and leaves was generally increased upon increasing FGD gypsum application rates. Some mercury was likely absorbed by leaves of plants from emitted mercury in the atmosphere. 相似文献
908.
锡林郭勒盟是我国重要的煤炭能源基地,近年来,煤电一体化开发为地区带来经济效益的同时也给环境带来巨大压力,大面积的草原受到破坏和威胁,引发了一系列生态问题,需要在锡盟未来的地区经济发展中引起注意。应该借鉴国际上对煤炭业开征环境保护税的经验,进行我国草原区煤炭业环境保护税费改革的制度设计和政策落实。 相似文献
909.
环境条件变化对河流沉积物“三氮”释放的影响 总被引:1,自引:0,他引:1
以京杭运河某断面沉积物和上覆水为研究对象,利用室内模拟试验探讨了3种环境条件(温度,曝气复氧,pH值)变化对河道沉积物"三氮"释放的影响。结果表明:5℃时上覆水氨氮和硝态氮累积量高于25℃,25℃时上覆水亚硝态氮累积量高于5℃,冬季低温条件下沉积物氨氮和硝态氮释放对上覆水的影响不容忽视。曝气复氧能抑制沉积物氨氮的释放和加速硝化作用而消耗氨氮,并促进亚硝态氮和硝态氮的生成,但是复氧初期可能致使上覆水氨氮含量上升。pH值越低,上覆水氨氮累积量越大,1 d后pH 4条件下的底泥氨累积量为pH 10时的1.8倍,pH 7~8.5条件下上覆水亚硝态氮累积速度最快,硝态氮累积速率最低。 相似文献
910.
Pan Dan Fan Wenchao 《Environmental science and pollution research international》2021,28(12):14764-14781
Environmental Science and Pollution Research - Environmental information disclosure (EID) is playing an increasingly important role in water pollution management. However, since EID is hard to... 相似文献