The ozone consumption effect and organic removal ability of metal coated cordierite ceramic honeycombs catalytic ozonation (catazone) process and ozonation process were comparatively studied by pilot-scale experimen...The ozone consumption effect and organic removal ability of metal coated cordierite ceramic honeycombs catalytic ozonation (catazone) process and ozonation process were comparatively studied by pilot-scale experiments. By Scan Electron Microscope (SEM), Atomic Force Microscope (AFM), BET, and X-ray photoelectron spectroscopy (XPS) analysis, metal oxides attached to ceramic surface were found to be in the form of crystal cluster, and the pore structure of ceramics was less developed. The air flow statuses of vacant catazone and ozone contactors were inclined to be plug-flow and mixed flow, respectively. Comparing with ozonation process, the ozone mass transfer efficiency of catazone process is lower, and the ozone decomposition efficiency of catazone is higher. The former effect is more obvious in semi-batch experiment, and the latter effect is more obvious in continuous-flow experiment. Unsaturated organics removal efflciencies of the two oxidation processes are similar, and are less affected by dissolved ozone concentration when it is higher than 1 mg/L. More dissolved organics were detected in catazone process in continuous.flow reaction, and more CH3CI3 formation potential (CH3CI3FP) was removed by catazone in semi-batch mode, especially in the water with lower UV254 .展开更多
By combining top-level design with local pilot practices,rural land system reform,as an important priority on the agenda of deepening comprehensive reform,has accumulated a series of replicable and applicable experien...By combining top-level design with local pilot practices,rural land system reform,as an important priority on the agenda of deepening comprehensive reform,has accumulated a series of replicable and applicable experiences that are conducive to amendments to relevant laws.This paper takes stock of the basic experience of Pidu District in addressing typical problems arising in its rural land system reform and then investigates the inner link between the reform and the persistence of high housing prices in cities,the capital flowing to the countryside,and the rural revitalization program.Based on this analysis,the author puts forward three basic directions of the rural land system reform:remain committed to marketization,balance the interests of all parties and promote the development of rural industries.展开更多
Heterogeneous agglomeration (HA) is a very potential technology for coal-fired flue gas treatment.In this paper,the distribution and migration mechanisms of trace elements (TEs such as Se,As and Pb in CFPPs were studi...Heterogeneous agglomeration (HA) is a very potential technology for coal-fired flue gas treatment.In this paper,the distribution and migration mechanisms of trace elements (TEs such as Se,As and Pb in CFPPs were studied on a 30,000 m^(3)/hr pilot-scale experimental plat form.The influences of HA on the removal efficiency of gaseous and particulate TEs were well analyzed.The results showed that Se,As and Pb were enriched in fly ash,and their sen sitivity to particle size is quite different.The content of Se was the highest in PM1,reaching193.04 mg/kg at the electrostatic precipitator (ESP) outlet.The average particle size of the total dust before ESP increased significantly from 21.686 to 62.612μm after injecting the heterogeneous agglomeration adsorbent,conducive to its further removal by ESP.In addi tion,the concentrations of gaseous Se,As and Pb in the flue gas decreased after adsorben spray,and accordingly,their contents in the hierarchical particles increased,indicating tha the adsorbent could effectively promote the adsorption of gaseous trace elements in fly ash and reduce the possibility of their escape to the atmosphere.Total concentrations of Se,As and Pb emitted by wet flue gas desulfurization (WFGD) are 0.223,0.668 and 0.076μg/m^(3)which decreased by 59.98%,47.69%and 90.71%,respectively.Finally,a possible HA mecha nism model was proposed,where chemical adsorption,physical condensation and collision agglomeration of gaseous TEs and fine particles with adsorbent droplets occurred to form larger agglomerates.展开更多
Background The fluorosis derived from coal burning is a very serious problem in China. By using fluorine-fixing technology during coal burning we are able to reduce the release of fluorides in coal at the source in or...Background The fluorosis derived from coal burning is a very serious problem in China. By using fluorine-fixing technology during coal burning we are able to reduce the release of fluorides in coal at the source in order to reduce pollution to the surrounding environment by coal burning pollutants as well as decrease the intake and accumulating amounts of fluorine in the human body. The aim of this study was to conduct a pilot experiment on calcium-based fluorine-fixing material efficiency during coal burning to demonstrate and promote the technology based on laboratory research. Methods A proper amount of calcium-based fluorine sorbent was added into high-fluorine coal to form briquettes so that the fluorine in high-fluorine coal can be fixed in coal slag and its release into atmosphere reduced. We determined figures on various components in briquettes and fluorine in coal slag as well as the concentrations of indoor air pollutants, including fluoride, sulfur dioxide and respirable particulate matter (RPM), and evaluated the fluorine-fixing efficiency of calcium-based fluorine sorbents and the levels of indoor air pollutants. Results Pilot experiments on fluorine-fixing efficiency during coal burning as well as its demonstration and promotion were carried out separately in Guiding and Longli Counties of Guizhou Province, two areas with coal burning fluorosis problems. If the calcium-based fluorine sorbent mixed coal was made into honeycomb briquettes the average fluorine-fixing ratio in the pilot experiment was 71.8%. If the burning calcium-based fluorine-fixing bitumite was made into a coalball, the average of fluorine-fixing ratio was 77.3%. The concentration of fluoride, sulfur dioxide and PM10 of indoor air were decreased significantly. There was a 10% increase in the cost of briquettes due to the addition of calcium-based fluorine sorbent. Conclusions The preparation process of calcium-based fluorine-fixing briquette is simple yet highly flammable and it is applicable to regions with abundant bitumite coal. As a small scale application, villagers may make fluorine-fixing coalballs or briquettes by themselves, achieving the optimum fluorine-fixing efficiency and reducing indoor air pollutants providing environmental and social benefits.展开更多
Simulation technique has been employed to predict rice yield of Kandhamal plateaus in Orissa(India)using the data of previous years.Preliminary simulation model has been developed The test for uniformity and independe...Simulation technique has been employed to predict rice yield of Kandhamal plateaus in Orissa(India)using the data of previous years.Preliminary simulation model has been developed The test for uniformity and independence has been conducted using Kolmogrov–smironov test and auto-correlation test,respectively.The result obtained has been subjected to testing of hypothesis by using two sided test.Data for five years(1995 to 2000)are used for model validation and the sample size is increased to 12 years i.e.,from 1995 to 2007 for prediction up to 2012.Sensitivity analysis is conducted by changing the parameters within feasible limits to find out the effect on the model.展开更多
文摘The ozone consumption effect and organic removal ability of metal coated cordierite ceramic honeycombs catalytic ozonation (catazone) process and ozonation process were comparatively studied by pilot-scale experiments. By Scan Electron Microscope (SEM), Atomic Force Microscope (AFM), BET, and X-ray photoelectron spectroscopy (XPS) analysis, metal oxides attached to ceramic surface were found to be in the form of crystal cluster, and the pore structure of ceramics was less developed. The air flow statuses of vacant catazone and ozone contactors were inclined to be plug-flow and mixed flow, respectively. Comparing with ozonation process, the ozone mass transfer efficiency of catazone process is lower, and the ozone decomposition efficiency of catazone is higher. The former effect is more obvious in semi-batch experiment, and the latter effect is more obvious in continuous-flow experiment. Unsaturated organics removal efflciencies of the two oxidation processes are similar, and are less affected by dissolved ozone concentration when it is higher than 1 mg/L. More dissolved organics were detected in catazone process in continuous.flow reaction, and more CH3CI3 formation potential (CH3CI3FP) was removed by catazone in semi-batch mode, especially in the water with lower UV254 .
基金part of the periodical research achievements of “Research on the Integration of Core Values of Equality and Justice into Property Rights Protection Legislation”(18VHJ007)a key program funded by the National Social Science Foundation in 2018
文摘By combining top-level design with local pilot practices,rural land system reform,as an important priority on the agenda of deepening comprehensive reform,has accumulated a series of replicable and applicable experiences that are conducive to amendments to relevant laws.This paper takes stock of the basic experience of Pidu District in addressing typical problems arising in its rural land system reform and then investigates the inner link between the reform and the persistence of high housing prices in cities,the capital flowing to the countryside,and the rural revitalization program.Based on this analysis,the author puts forward three basic directions of the rural land system reform:remain committed to marketization,balance the interests of all parties and promote the development of rural industries.
基金supported by the National Key Research and Development Program (No. 2018YFB0605104)the National Natural Science Foundation of China (No. 42030807)+1 种基金the Program for HUST Academic Frontier Youth Team (No. 2018QYTD05)the Hubei Provincial Key Research and Development Program (No. 2020BCA076)。
文摘Heterogeneous agglomeration (HA) is a very potential technology for coal-fired flue gas treatment.In this paper,the distribution and migration mechanisms of trace elements (TEs such as Se,As and Pb in CFPPs were studied on a 30,000 m^(3)/hr pilot-scale experimental plat form.The influences of HA on the removal efficiency of gaseous and particulate TEs were well analyzed.The results showed that Se,As and Pb were enriched in fly ash,and their sen sitivity to particle size is quite different.The content of Se was the highest in PM1,reaching193.04 mg/kg at the electrostatic precipitator (ESP) outlet.The average particle size of the total dust before ESP increased significantly from 21.686 to 62.612μm after injecting the heterogeneous agglomeration adsorbent,conducive to its further removal by ESP.In addi tion,the concentrations of gaseous Se,As and Pb in the flue gas decreased after adsorben spray,and accordingly,their contents in the hierarchical particles increased,indicating tha the adsorbent could effectively promote the adsorption of gaseous trace elements in fly ash and reduce the possibility of their escape to the atmosphere.Total concentrations of Se,As and Pb emitted by wet flue gas desulfurization (WFGD) are 0.223,0.668 and 0.076μg/m^(3)which decreased by 59.98%,47.69%and 90.71%,respectively.Finally,a possible HA mecha nism model was proposed,where chemical adsorption,physical condensation and collision agglomeration of gaseous TEs and fine particles with adsorbent droplets occurred to form larger agglomerates.
文摘Background The fluorosis derived from coal burning is a very serious problem in China. By using fluorine-fixing technology during coal burning we are able to reduce the release of fluorides in coal at the source in order to reduce pollution to the surrounding environment by coal burning pollutants as well as decrease the intake and accumulating amounts of fluorine in the human body. The aim of this study was to conduct a pilot experiment on calcium-based fluorine-fixing material efficiency during coal burning to demonstrate and promote the technology based on laboratory research. Methods A proper amount of calcium-based fluorine sorbent was added into high-fluorine coal to form briquettes so that the fluorine in high-fluorine coal can be fixed in coal slag and its release into atmosphere reduced. We determined figures on various components in briquettes and fluorine in coal slag as well as the concentrations of indoor air pollutants, including fluoride, sulfur dioxide and respirable particulate matter (RPM), and evaluated the fluorine-fixing efficiency of calcium-based fluorine sorbents and the levels of indoor air pollutants. Results Pilot experiments on fluorine-fixing efficiency during coal burning as well as its demonstration and promotion were carried out separately in Guiding and Longli Counties of Guizhou Province, two areas with coal burning fluorosis problems. If the calcium-based fluorine sorbent mixed coal was made into honeycomb briquettes the average fluorine-fixing ratio in the pilot experiment was 71.8%. If the burning calcium-based fluorine-fixing bitumite was made into a coalball, the average of fluorine-fixing ratio was 77.3%. The concentration of fluoride, sulfur dioxide and PM10 of indoor air were decreased significantly. There was a 10% increase in the cost of briquettes due to the addition of calcium-based fluorine sorbent. Conclusions The preparation process of calcium-based fluorine-fixing briquette is simple yet highly flammable and it is applicable to regions with abundant bitumite coal. As a small scale application, villagers may make fluorine-fixing coalballs or briquettes by themselves, achieving the optimum fluorine-fixing efficiency and reducing indoor air pollutants providing environmental and social benefits.
文摘Simulation technique has been employed to predict rice yield of Kandhamal plateaus in Orissa(India)using the data of previous years.Preliminary simulation model has been developed The test for uniformity and independence has been conducted using Kolmogrov–smironov test and auto-correlation test,respectively.The result obtained has been subjected to testing of hypothesis by using two sided test.Data for five years(1995 to 2000)are used for model validation and the sample size is increased to 12 years i.e.,from 1995 to 2007 for prediction up to 2012.Sensitivity analysis is conducted by changing the parameters within feasible limits to find out the effect on the model.