The selective leaching and recovery of zinc in a zinciferous sediment from a synthetic wastewater treatment was investigated.The main composition of the sediment includes 6% zinc and other metal elements such as Ca,Fe...The selective leaching and recovery of zinc in a zinciferous sediment from a synthetic wastewater treatment was investigated.The main composition of the sediment includes 6% zinc and other metal elements such as Ca,Fe,Cu,Mg.The effects of sulfuric acid concentration,temperature,leaching time and the liquid-to-solid ratio on the leaching rate of zinc were studied by single factor and orthogonal experiments.The maximum difference of leaching rate between zinc and iron,89.85%,was obtained by leaching under 170 g/L H2SO4 in liquid-to-solid ratio 4.2 mL/g at 65 ℃ for 1 h,and the leaching rates of zinc and iron were 91.20% and 1.35%,respectively.展开更多
Organic solid and liquid wastes contain large amounts of energy, nutrients, and water, and should not be perceived as merely waste. Recycling, composting, and combustion of non-recyclables have been practiced for deca...Organic solid and liquid wastes contain large amounts of energy, nutrients, and water, and should not be perceived as merely waste. Recycling, composting, and combustion of non-recyclables have been practiced for decades to capture the energy and values from municipal solid wastes. Treatment and disposal have been the primary management strategy for wastewater. As new technologies are emerging, alternative options for the utilization of both solid wastes and wastewater have become available. Considering the complexity of the chemical, physical, and biological properties of these wastes, multiple technologies may be required to maximize the energy and value recovery from the wastes. For this purpose, biorefin- ing tends to be an appropriate approach to completely utilize the energy and value available in wastes. Research has demonstrated that non-recyclable waste materials and bio-solids can be converted into usable heat, electricity, fuel, and chemicals through a variety of processes, and the liquid waste streams have the potential to support crop and algae growth and provide other energy recovery and food production options. In this paper, we propose new biorefining schemes aimed at organic solid and liquid wastes from municipal sources, food and biological processing plants, and animal production facilities. Four new breakthrough technologies-namely, vacuum-assisted thermophilic anaerobic digestion, extended aquaponics, oily wastes to biodiesel via glycerolysis, and microwave-assisted thermochemical conversion-can be incorporated into the biorefining schemes, thereby enabling the complete utilization of those wastes for the production of chemicals, fertilizer, energy （biogas, syngas, biodiesel, and bio-oil）, foods, and feeds, and resulting in clean water and a significant reduction in pollutant emissions.展开更多
文摘The selective leaching and recovery of zinc in a zinciferous sediment from a synthetic wastewater treatment was investigated.The main composition of the sediment includes 6% zinc and other metal elements such as Ca,Fe,Cu,Mg.The effects of sulfuric acid concentration,temperature,leaching time and the liquid-to-solid ratio on the leaching rate of zinc were studied by single factor and orthogonal experiments.The maximum difference of leaching rate between zinc and iron,89.85%,was obtained by leaching under 170 g/L H2SO4 in liquid-to-solid ratio 4.2 mL/g at 65 ℃ for 1 h,and the leaching rates of zinc and iron were 91.20% and 1.35%,respectively.
基金Department of Transport/Sun GrantUS Department of Agriculture/ Department of Energy+4 种基金Minnesota Legislative-Citizen Commission on Minnesota ResourcesMetropolitan Council Environmental ServicesUniversity of Minnesota MNDrive programsUniversity of Minnesota Center for BiorefiningChina Scholarship Council (CSC) for their financial support for this work
文摘Organic solid and liquid wastes contain large amounts of energy, nutrients, and water, and should not be perceived as merely waste. Recycling, composting, and combustion of non-recyclables have been practiced for decades to capture the energy and values from municipal solid wastes. Treatment and disposal have been the primary management strategy for wastewater. As new technologies are emerging, alternative options for the utilization of both solid wastes and wastewater have become available. Considering the complexity of the chemical, physical, and biological properties of these wastes, multiple technologies may be required to maximize the energy and value recovery from the wastes. For this purpose, biorefin- ing tends to be an appropriate approach to completely utilize the energy and value available in wastes. Research has demonstrated that non-recyclable waste materials and bio-solids can be converted into usable heat, electricity, fuel, and chemicals through a variety of processes, and the liquid waste streams have the potential to support crop and algae growth and provide other energy recovery and food production options. In this paper, we propose new biorefining schemes aimed at organic solid and liquid wastes from municipal sources, food and biological processing plants, and animal production facilities. Four new breakthrough technologies-namely, vacuum-assisted thermophilic anaerobic digestion, extended aquaponics, oily wastes to biodiesel via glycerolysis, and microwave-assisted thermochemical conversion-can be incorporated into the biorefining schemes, thereby enabling the complete utilization of those wastes for the production of chemicals, fertilizer, energy （biogas, syngas, biodiesel, and bio-oil）, foods, and feeds, and resulting in clean water and a significant reduction in pollutant emissions.
