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1.
为实现白洋淀芦苇的有效利用,以白洋淀淀区芦苇(白苇)为原料,以KOH、K2CO3为活化剂,综合考虑制备过程中的剂料比、浸渍时间、活化温度、活化时间等因素的影响,通过正交试验,以碘吸附值和亚甲蓝吸附值综合作为吸附性能高低的评价标准,进行活性炭制备方法研究。结果表明:在以KOH为活化剂、剂料比为4∶1、浸渍时间36 h、850℃下活化1 h的条件下,制备的芦苇基生物质活性炭碘吸附值最高,亚甲基蓝吸附值较高;以K2CO3为活化剂、剂料比为3∶1、浸渍时间12 h、900℃下活化2 h的条件下,制备的芦苇基生物质活性炭有最高的碘吸附值和对亚甲蓝具有良好的吸附性。制备的生物质活性炭碘吸附值均高于国家活性炭一级品标准(1 000 mg/g),具备一定的实用性。 相似文献
2.
Boyi Cheng Yi Wang Yumei Hua Kate V. Heal 《Frontiers of Environmental Science & Engineering》2021,15(4):73
3.
中国水泥行业面临巨大的碳达峰与碳中和压力.CO2捕集利用与封存(CCUS)技术是能够实现化石资源低碳利用的碳减排技术.在中国水泥企业数据基础上,采用全流程CCUS系统模型(ITEAM-CCUS)评估CCUS的碳减排潜力对水泥企业碳中和非常重要.模型从源汇匹配距离、捕集率、CCUS技术和技术水平这4个方面设置了10种情景,完成了水泥行业的企业筛选、场地筛选、CCUS技术经济评估和源汇匹配,初步回答了水泥企业结合CCUS的封存场地、减排规模、成本范围和优先项目分布等关键问题.在250 km匹配距离、85%净捕集率、CO2-EWR技术和当前技术水平情景,44%的水泥企业可以利用CO2强化地下水开采(CO2-EWR)技术开展碳减排,累计年碳减排量为6.25亿t,平准化成本为290~1838元·t-1;具有全流程CO2-EWR早期示范优势的地区为新疆、内蒙古、宁夏、河南和河北等.水泥企业开展全流程CCUS项目技术可行,可以实现大规模CO2减排,低成本项目具有早期示范机会.研究结果可为水泥行业低碳发展和CCUS商业化部署提供定量参考. 相似文献
4.
Chinazaekpere Nwani Festus V. Bekun Bright A. Gyamfi Ekpeno L. Effiong Andrew A. Alola 《Natural resources forum》2023,47(2):155-176
Sustainable use of natural resources would entail ensuring that derived economic benefits today do not undermine the welfare of generations to come. On this basis, this study examines the nexus between natural resource rents and carbon dioxide (CO2) emissions disaggregated into production and consumption-based (i.e., trade-adjusted) CO2 emissions for a selected panel of 45 developing and transition economies over the period 1995–2017. The empirical model also incorporates the impacts of population, affluence, and energy intensity. The results show that affluence increases production-based CO2 emissions by 1.407%, with the EKC's predicted inverted U-shaped curve only explaining consumption-based CO2 emissions. Economic reliance on natural resource rents and energy intensification contribute 0.022% and 0.766%, respectively, to CO2 emissions embedded in territorial production inventories and 0.035% and 0.583%, respectively, to CO2 emissions embedded in consumption inventories. The bootstrap non-causality test shows that historical data on each variable has significant predictive power for future CO2 emissions from both sources. The historical information about natural resource rents has significant predictive power over the future levels of affluence and energy intensity. Clearly, the results show that the environmental impact of natural resource rents is stronger when CO2 emissions are adjusted for trade and varies among the countries, with Bangladesh, Guinea, India, Malaysia, Mexico, Nigeria, Pakistan, Saudi Arabia, Vietnam, and Zimbabwe among the most affected countries. Overall, this study provides motivation for policies to keep the use of natural resources within sustainable limits. 相似文献
5.
The iron and steel industry is not only an important foundation of the national economy, but also the largest source of industrial air pollution. Due to the current status of emissions in the iron and steel industry, ultra-low pollutant emission control technology has been researched and developed. Liquid-phase proportion control technology has been developed for magnesian fluxed pellets, and a blast furnace smelting demonstration project has been established to use a high proportion of fluxed pellets (80%) for the first time in China to realize source emission reduction of SO2 and NOx. Based on the characteristics of high NOx concentrations and the coexistence of multiple pollutants in coke oven flue gas, low-NOx combustion coupled with multi-pollutant cooperative control technology with activated carbon was developed to achieve efficient removal of multiple pollutants and resource utilization of sulfur. Based on the characteristics of co-existing multiple pollutants in pellet flue gas, selective non-catalytic reduction (SNCR) coupled with ozone oxidation and spray drying adsorption (SDA) was developed, which significantly reduces the operating cost of the system. In the light of the high humidity and high alkalinity in flue gas, filter materials with high humidity resistance and corrosion resistance were manufactured, and an integrated pre-charged bag dust collector device was developed, which realized ultra-low emission of fine particles and reduced filtration resistance and energy consumption in the system. Through source emission reduction, process control and end-treatment technologies, five demonstration projects were built, providing a full set of technical solutions for ultra-low emissions of dust, SO2, NOx, SO3, mercury and other pollutants, and offering technical support for the green development of the iron and steel industry. 相似文献
6.
收集整理1992年1月至2022年5月长江经济带地区长期定位施肥试验文献,提取并整合了其中农田土壤有机碳的资料.采用归一化处理和变化速率的分析方法,研究长期不同施肥措施下长江经济带地区农田土壤有机碳含量的总体变化,并比较3种耕作模式及不同土壤类型下土壤有机碳含量的变化差异,判断分析试验持续年限长短对土壤有机碳动态的影响.结果表明,在长期不同施肥措施下,我国长江经济带地区农田土壤有机碳含量整体呈上升趋势,无机氮肥磷肥配施(NP)、无机氮磷钾肥配施(NPK)、单独施用有机肥(O)和有机无机肥配施(NPKO)处理均能增加农田土壤的有机碳含量,其中以NPKO处理为最大,而单独施用无机氮肥(N)则会降低土壤有机碳含量.旱田、水田和水旱轮作农田土壤有机碳含量变化速率分别为0.22、 0.24和0.16g·(kg·a)-1,3种耕作模式在土壤固碳效果方面并无显著性差异.O和NPKO处理下所带来的有机碳相对快速增加效应在旱田土壤中的持续年限最高不超过28 a,而在水田及水旱轮作土壤中依然可以持续到28 a以上.在不同的土壤类型下,土壤有机碳含量的变化速率存在着一定的差异,平均有机... 相似文献
7.
《环境科学学报(英文版)》2023,35(2):491-504
Ce1-xZrxO2 composite oxides (molar, x = 0-1.0, interval of 0.2) were prepared by a cetyltrimethylammonium bromide-assisted precipitation method. The enhancement of silver-species modification and catalytic mechanism of adsorption-transformation-desorption process were investigated over the Ag-impregnated catalysts for low-temperature selective catalytic oxidation of ammonia (NH3-SCO). The optimal 5 wt.% Ag/Ce0.6Zr0.4O2 catalyst presented good NH3-SCO performance with >90% NH3 conversion at temperature (T) ≥ 250°C and 89% N2 selectivity. Despite the irregular block shape and underdeveloped specific surface area (∼60 m2/g), the naked and Ag-modified Ce0.6Zr0.4O2 solid solution still obtained highly dispersed distribution of surface elements analyzed by scanning electron microscope-energy dispersive spectrometer (SEM-EDS) (mapping), N2 adsorption-desorption test and X-ray diffraction (XRD). H2 temperature programmed reduction (H2-TPR) and X-ray photoelectron spectroscopy (XPS) results indicated that Ag-modification enhanced the mobility and activation of oxygen-species leading to a promotion on CeO2 reducibility and synergistic Ag0/Ag+ and Ce4+/Ce3+ redox cycles. Besides, Ag+/Ag2O clusters could facilitate the formation of surface oxygen vacancies that was beneficial to the adsorption and activation of ammonia. NH3-temperature programmed desorption (NH3-TPD) showed more adsorption-desorption capacity to ammonia were provided by physical, weak- and medium-strong acid sites. Diffused reflectance infrared Fourier transform spectroscopy (DRIFTS) experiments revealed the activation of ammonia might be the control step of NH3-SCO procedure, during which NH3 dehydrogenation derived from NHx-species and also internal selective catalytic reduction (i-SCR) reactions were proposed. 相似文献
8.
Self-ignition of solid fuels storage is one of the main causes of human and economic losses. Additionally, each fire caused by this phenomenon emits an amount of toxic gases that contributes on the development of climate change. Nowadays, several methodologies are used in order to detect the self-ignition tendency of solid fuels, but they have as main disadvantages the amount of money and time that they require. The aim of this study is to propose a methodology of detection of incipient self-ignition of solid fuels through the measurement of gas emissions. This study compares existing methodologies to detect self-ignition tendency, such as TG, DSC or susceptibility, and to combustion related gas emission results. Different methods have been used to evaluate the results from the gas emission test, showing that interval and inflexion methods provide early detection of the self-heating process. With this methodology, it is possible to determine this process in advance with the equipment currently available in every industrial facility, reducing costs and improving efficiency. 相似文献
9.
Yuqing Xu Zedong Lu Wenjun Sun Xiaohui Zhang 《Frontiers of Environmental Science & Engineering》2021,15(6):131
10.
Shanwei Ma Hang Li Guan Zhang Tahir Iqbal Kai Li Qiang Lu 《Frontiers of Environmental Science & Engineering》2021,15(2):25