The quantitative and qualitative composition of Chinese municipal solid waste (MSW) differs significantly from German waste. The focus of this paper is on whether these differences also lead to dissimilar qualities of...The quantitative and qualitative composition of Chinese municipal solid waste (MSW) differs significantly from German waste. The focus of this paper is on whether these differences also lead to dissimilar qualities of leachates during storage or landfilling. Leachates ingredients determine the appropriate treatment technique. MSW compositions of the two cities Guilin (China) and Essen (Germany), each with approx. 600 000 inhabitants, are used to simulate Chinese and German MSW types. A sequencing batch reactor (SBR) is used, combining aerobic and anaerobic reaction principles, to test the biodegradability of leachates. Leachates are tested for temperature, pH-value, redox potentials, and oxygen concentration. Chemical oxygen demand (COD) values are determined. Within 8 h, the biodegradation rates for both kinds of leachates are more than 90%. Due to the high organic content of Chinese waste, the degradation rate for Guilin MSW leachate is even higher, up to 97%. The effluent from SBR technique is suitable for direct discharge into bodies of water.展开更多
The effect of moisture in municipal solid waste (MSW) on partitioning of lead (Pb), zinc (Zn), copper (Cu) and cadmium (Cd) was studied in a laboratory tubular furnace by using simulated MSW. The moisture in MSW influ...The effect of moisture in municipal solid waste (MSW) on partitioning of lead (Pb), zinc (Zn), copper (Cu) and cadmium (Cd) was studied in a laboratory tubular furnace by using simulated MSW. The moisture in MSW influences heavy metals in following ways, to increase the moisture in flue gas and decrease the combustion temperature, to prolong the combustion time, and to prolong the releasing time of volatiles with the furnace temperature decreased by increasing the moisture. The volatilization of Pb, Zn and Cd was enhanced by increasing the moisture in MSW because of the prolonged combustion time. For Pb and Zn, the combustion time was important at higher temperature, while for Cd, it was important at low temperature. The moisture content showed slight effect on Cu partitioning. When extra chlorine was added to MSW, such as 1%PVC + 0.5%NaCl, the volatilization of Pb, Zn and Cu was enhanced by increasing the moisture because water evaporation reduced the temperature and increased devolatilization time. At higher temperature, NaCl tends to decompose and generates more free chlorine, producing more metal chlorides. Since Cd is a strong volatile heavy metal in MSW, the effect of moisture content on its volatilization is less than that of Pb, Zn or Cu during the MSW incineration.展开更多
Municipal solid waste （MSW） and its disposal are gaining significant importance in geotechnical and geoenvironmental engineering. However, conventional research is primarily focused on fresh MSW or MSW that is compa...Municipal solid waste （MSW） and its disposal are gaining significant importance in geotechnical and geoenvironmental engineering. However, conventional research is primarily focused on fresh MSW or MSW that is compacted under its own weight in the landfill. In this work, a series of tests to study the properties of a densified MSW after ground treatment were presented. The tests involved oedometer test, simple shear test, triaxial shear test, and permeability test, which were conducted to investigate the compressibility, shear strength, creep behavior and permeability of the MSW. The results show that the compressibility modulus of the MSW increases as the dry density increases. However, the influence of density on modulus decreases once the density reaches a certain value. Like most soils, the stress-strain curve of the densified MSW can be approximated by a hyperbola in the triaxial shear test. Fibrous components provide additional cohesion for MSW, but have a relatively smaller effect on friction angle. Permeability is also found to be closely related to the dry density of the MSW, i.e., MSW with a higher dry density has a smaller permeability. The permeability coefficient may be less than 10 7 cm/s if the density is high enough.展开更多
The correct individuation of the best final destination for MSW cannot ignore the option of thermal treatment, taking into account both the possibility of energy recovery and the capacity of the thermal process to des...The correct individuation of the best final destination for MSW cannot ignore the option of thermal treatment, taking into account both the possibility of energy recovery and the capacity of the thermal process to destroy an important part of the pollutants that are originally present in the waste itself. In order to realize this operation, it is possible to use conventional incineration systems, but also to consider new innovative processes and technologies; among them, production of RDF （refuse derived fuel） is quite often used in process plants, and gasification of waste seems to be a promising solution. The aim of the present paper is a critical analysis of the above-mentioned solutions, not only from the operational point of view but also on the basis of the status of the art of practical applications and in consideration of the most significant results for the Italian and European situation. For the application of these technologies a specific Italian case has been considered： it consists of the correct individuation of waste management modality for final destination of wastes produced in a city located in Piedmont （north of Italy）. The results of the analysis highlight the environmental and economic convenience, for the specific considered case, of the direct combustion in incineration plant of the all amount of the wastes produced. From the considered specific example some more general conclusions can be drawn.展开更多
The article reveals the potential of information technology in decision issues of municipal solid waste. The technique proposed for definition of ecological and technical potential for ecological optimization of the t...The article reveals the potential of information technology in decision issues of municipal solid waste. The technique proposed for definition of ecological and technical potential for ecological optimization of the territory for the purpose of efficient decision-making in the environmental field. Studies are based on the information capacity usage and implementation of geographic information technologies in combination with the methods of remote sensing of the earth. On this basis, the authors have developed mechanisms that will overcome the existing environmental and technical challenges--economic, political and human capital.展开更多
Developments of these last two decades in Albania after the fall of communism are associated with major changes both in terms of socio-economic and environmental simultaneously. In the context as for environmental cha...Developments of these last two decades in Albania after the fall of communism are associated with major changes both in terms of socio-economic and environmental simultaneously. In the context as for environmental change, Albania is one of the countries with a wide range of problems that have been and are constantly in the focus of attention not only state institutions but also non-governmental organizations operating in authors＇ country. In this city that appears to approach a problem from the stand point of the environment is Tirana. Tirana as the capital of this country has experienced two decades such an extra ordinary transformation that has not been without its environmental costs. Human activities have transformed the environment in Tirana. Greater quantities of waste generated especially solid waste are those caused by major construction boom in Tirana performed. Considerable amount of clinical waste involved in urban waste, in places where hospital, sand clinics, and though a part of Tirana clinical waste burned in special places. With the economy in this city, this volume will increase. In this context, authors＇ theme will focus on a more extensive treatment of these problem, sand forecasts above are provided in the future as well as measures to reduce them to levels required by the EU and to have a quality of life good.展开更多
基金Project supported by German Ministries of the State North Rhine-Westphalia
文摘The quantitative and qualitative composition of Chinese municipal solid waste (MSW) differs significantly from German waste. The focus of this paper is on whether these differences also lead to dissimilar qualities of leachates during storage or landfilling. Leachates ingredients determine the appropriate treatment technique. MSW compositions of the two cities Guilin (China) and Essen (Germany), each with approx. 600 000 inhabitants, are used to simulate Chinese and German MSW types. A sequencing batch reactor (SBR) is used, combining aerobic and anaerobic reaction principles, to test the biodegradability of leachates. Leachates are tested for temperature, pH-value, redox potentials, and oxygen concentration. Chemical oxygen demand (COD) values are determined. Within 8 h, the biodegradation rates for both kinds of leachates are more than 90%. Due to the high organic content of Chinese waste, the degradation rate for Guilin MSW leachate is even higher, up to 97%. The effluent from SBR technique is suitable for direct discharge into bodies of water.
基金Supported by the National Basic Research Program of China (2011CB201502)
文摘The effect of moisture in municipal solid waste (MSW) on partitioning of lead (Pb), zinc (Zn), copper (Cu) and cadmium (Cd) was studied in a laboratory tubular furnace by using simulated MSW. The moisture in MSW influences heavy metals in following ways, to increase the moisture in flue gas and decrease the combustion temperature, to prolong the combustion time, and to prolong the releasing time of volatiles with the furnace temperature decreased by increasing the moisture. The volatilization of Pb, Zn and Cd was enhanced by increasing the moisture in MSW because of the prolonged combustion time. For Pb and Zn, the combustion time was important at higher temperature, while for Cd, it was important at low temperature. The moisture content showed slight effect on Cu partitioning. When extra chlorine was added to MSW, such as 1%PVC + 0.5%NaCl, the volatilization of Pb, Zn and Cu was enhanced by increasing the moisture because water evaporation reduced the temperature and increased devolatilization time. At higher temperature, NaCl tends to decompose and generates more free chlorine, producing more metal chlorides. Since Cd is a strong volatile heavy metal in MSW, the effect of moisture content on its volatilization is less than that of Pb, Zn or Cu during the MSW incineration.
基金Foundation item： Project（50979047） supported by the National Natural Science Foundation of China Project（2010CB732103） supported by the National Basic Research Program of China Project（2012-KY-02） supported by the State Key Laboratory of Hydroscience and Engineering （Tsinghua University）, China
文摘Municipal solid waste （MSW） and its disposal are gaining significant importance in geotechnical and geoenvironmental engineering. However, conventional research is primarily focused on fresh MSW or MSW that is compacted under its own weight in the landfill. In this work, a series of tests to study the properties of a densified MSW after ground treatment were presented. The tests involved oedometer test, simple shear test, triaxial shear test, and permeability test, which were conducted to investigate the compressibility, shear strength, creep behavior and permeability of the MSW. The results show that the compressibility modulus of the MSW increases as the dry density increases. However, the influence of density on modulus decreases once the density reaches a certain value. Like most soils, the stress-strain curve of the densified MSW can be approximated by a hyperbola in the triaxial shear test. Fibrous components provide additional cohesion for MSW, but have a relatively smaller effect on friction angle. Permeability is also found to be closely related to the dry density of the MSW, i.e., MSW with a higher dry density has a smaller permeability. The permeability coefficient may be less than 10 7 cm/s if the density is high enough.
文摘The correct individuation of the best final destination for MSW cannot ignore the option of thermal treatment, taking into account both the possibility of energy recovery and the capacity of the thermal process to destroy an important part of the pollutants that are originally present in the waste itself. In order to realize this operation, it is possible to use conventional incineration systems, but also to consider new innovative processes and technologies; among them, production of RDF （refuse derived fuel） is quite often used in process plants, and gasification of waste seems to be a promising solution. The aim of the present paper is a critical analysis of the above-mentioned solutions, not only from the operational point of view but also on the basis of the status of the art of practical applications and in consideration of the most significant results for the Italian and European situation. For the application of these technologies a specific Italian case has been considered： it consists of the correct individuation of waste management modality for final destination of wastes produced in a city located in Piedmont （north of Italy）. The results of the analysis highlight the environmental and economic convenience, for the specific considered case, of the direct combustion in incineration plant of the all amount of the wastes produced. From the considered specific example some more general conclusions can be drawn.
文摘The article reveals the potential of information technology in decision issues of municipal solid waste. The technique proposed for definition of ecological and technical potential for ecological optimization of the territory for the purpose of efficient decision-making in the environmental field. Studies are based on the information capacity usage and implementation of geographic information technologies in combination with the methods of remote sensing of the earth. On this basis, the authors have developed mechanisms that will overcome the existing environmental and technical challenges--economic, political and human capital.
文摘Developments of these last two decades in Albania after the fall of communism are associated with major changes both in terms of socio-economic and environmental simultaneously. In the context as for environmental change, Albania is one of the countries with a wide range of problems that have been and are constantly in the focus of attention not only state institutions but also non-governmental organizations operating in authors＇ country. In this city that appears to approach a problem from the stand point of the environment is Tirana. Tirana as the capital of this country has experienced two decades such an extra ordinary transformation that has not been without its environmental costs. Human activities have transformed the environment in Tirana. Greater quantities of waste generated especially solid waste are those caused by major construction boom in Tirana performed. Considerable amount of clinical waste involved in urban waste, in places where hospital, sand clinics, and though a part of Tirana clinical waste burned in special places. With the economy in this city, this volume will increase. In this context, authors＇ theme will focus on a more extensive treatment of these problem, sand forecasts above are provided in the future as well as measures to reduce them to levels required by the EU and to have a quality of life good.
