A glass crusher was developed to improve the waste glass crushing process.The waste glass was recycled,crushed and sieved to different particle sizes as glass aggregates,and the surface of glass aggregates was treated...A glass crusher was developed to improve the waste glass crushing process.The waste glass was recycled,crushed and sieved to different particle sizes as glass aggregates,and the surface of glass aggregates was treated by nano-Fe2O3 suspension to improve the anti-striping property.The glasphalt mixture made by partly replacing mineral aggregates with glass aggregates was designed and evaluated.The sizes of glass aggregates were selected to be 2.36 and 4.75 mm,and the optimum concentration of nano-Fe2O3 suspension was determined to be 10%.The optimum asphalt content(OAC)was determined by the Marshall method and the glass aggregate content.The influence of the glass aggregate content on the technical properties of glasphalt mixtures were analyzed by the rutting test,three-point bending test,freeze-thaw splitting test and skid resistance test.The results show that the optimal content of glass aggregates and OAC are recommended to be 15%and 4.4%,respectively.These environmentally-friendly glasphalt mixtures can solve the problem of environmental pollution caused by waste glass,as well as reducing the cost of pavement materials and construction.展开更多
Physical methods show great potential and advantages on comprehensive reutilization of waste printed circuit boards (PCBs) because of lower investment and operation cost, higher efficiency and environment friendliness...Physical methods show great potential and advantages on comprehensive reutilization of waste printed circuit boards (PCBs) because of lower investment and operation cost, higher efficiency and environment friendliness. However, metals contained in fine fraction of PCBs cannot be recovered effectively by conventional equipments such as high tension electrostatic separator or shaking table. In the paper, this conundrum was resolved successfully with the enhanced Falcon SB concentrator. The separation mechanism of Falcon SB concentrator was analyzed and main factors affecting separation efficiency such as magnitude of rotation frequency of bowl, water counter pressure and slurry concentration of feed were studied and interaction of factors above also were investigated using Design-Expert software. Experiment results show that complete liberation degree and great difference of density between metals and nonmetals are suitable to recover metals from -74 μm PCBs using enhanced Falcon SB concentrator and 80.77 % integration efficiency can be achieved when slurry concentration of feed is 40 g/L with the water counter pressure of 0.01 MPa and rotation frequency of 50 Hz.展开更多
This paper focuses on cement composites based on waste fine aggregate obtained from hydroclassification all-in-aggregate in the Central Pomerania region in northern Poland. In the world there are regions with poor sup...This paper focuses on cement composites based on waste fine aggregate obtained from hydroclassification all-in-aggregate in the Central Pomerania region in northern Poland. In the world there are regions with poor supplies of coarse aggregate, which is one of the most essential raw materials used for production of ordinary concrete. In these regions, instead of coarse aggregate, there are often very large deposits of fine aggregate such as natural sand and fine all-in-aggregate. These raw materials may be used for concrete production of standard mechanical properties. Manufacturing concrete based on locally available fine aggregate is inexpensive which encourages the local production of fine aggregate cement composites instead of ordinary concrete, requiring gravel transported from distant places.展开更多
基金The Project of the Department of Science&Technology of Shaanxi Province(No.2016KJXX-69,2016ZDJC-24,2017KCT-13)China Postdoctoral Science Foundation(No.2017M620434)the Special Fund for Basic Scientific Research of Central College of Chang’an University(No.310821153502,310821173501)
文摘A glass crusher was developed to improve the waste glass crushing process.The waste glass was recycled,crushed and sieved to different particle sizes as glass aggregates,and the surface of glass aggregates was treated by nano-Fe2O3 suspension to improve the anti-striping property.The glasphalt mixture made by partly replacing mineral aggregates with glass aggregates was designed and evaluated.The sizes of glass aggregates were selected to be 2.36 and 4.75 mm,and the optimum concentration of nano-Fe2O3 suspension was determined to be 10%.The optimum asphalt content(OAC)was determined by the Marshall method and the glass aggregate content.The influence of the glass aggregate content on the technical properties of glasphalt mixtures were analyzed by the rutting test,three-point bending test,freeze-thaw splitting test and skid resistance test.The results show that the optimal content of glass aggregates and OAC are recommended to be 15%and 4.4%,respectively.These environmentally-friendly glasphalt mixtures can solve the problem of environmental pollution caused by waste glass,as well as reducing the cost of pavement materials and construction.
基金Project 200360290015 supported by the Doctoral Program of Higher Education, China Ministry of Education
文摘Physical methods show great potential and advantages on comprehensive reutilization of waste printed circuit boards (PCBs) because of lower investment and operation cost, higher efficiency and environment friendliness. However, metals contained in fine fraction of PCBs cannot be recovered effectively by conventional equipments such as high tension electrostatic separator or shaking table. In the paper, this conundrum was resolved successfully with the enhanced Falcon SB concentrator. The separation mechanism of Falcon SB concentrator was analyzed and main factors affecting separation efficiency such as magnitude of rotation frequency of bowl, water counter pressure and slurry concentration of feed were studied and interaction of factors above also were investigated using Design-Expert software. Experiment results show that complete liberation degree and great difference of density between metals and nonmetals are suitable to recover metals from -74 μm PCBs using enhanced Falcon SB concentrator and 80.77 % integration efficiency can be achieved when slurry concentration of feed is 40 g/L with the water counter pressure of 0.01 MPa and rotation frequency of 50 Hz.
文摘This paper focuses on cement composites based on waste fine aggregate obtained from hydroclassification all-in-aggregate in the Central Pomerania region in northern Poland. In the world there are regions with poor supplies of coarse aggregate, which is one of the most essential raw materials used for production of ordinary concrete. In these regions, instead of coarse aggregate, there are often very large deposits of fine aggregate such as natural sand and fine all-in-aggregate. These raw materials may be used for concrete production of standard mechanical properties. Manufacturing concrete based on locally available fine aggregate is inexpensive which encourages the local production of fine aggregate cement composites instead of ordinary concrete, requiring gravel transported from distant places.