Post-combustion amine absorption and stripping can remove 90% of the CO2 from power plant flue gas, but systems can reduce electrical output by approximately 30% due to energy requirements for stripping CO2 from solve...Post-combustion amine absorption and stripping can remove 90% of the CO2 from power plant flue gas, but systems can reduce electrical output by approximately 30% due to energy requirements for stripping CO2 from solvent and CO2 compression. The CO2 capture energy penalty can be reduced while developing renewable energy technologies by meeting CO2 capture energy requirements with a solar thermal energy system, particularly when electricity demand and prices are the highest. This study presents an initial review of solar thermal technologies for supplying CO2 capture energy, with a focus on high temperature systems. Parabolic troughs and central receivers are technically able to provide energy for CO2 capture. However, the solar system's capital costs would be roughly half that of the base coal-fired plant with CO2 capture, and high electricity prices are required to offset the costs of operating the solar thermal system. For high temperature solar thermal systems, direct electricity generation is likely a more efficient way to use solar energy to replace output lost to CO2 capture energy. However, low temperature solar thermal systems might integrate better with solvent stripping equipment, and more rigorous analysis is required to definitively assess the feasibility of using solar energy for CO2 capture.展开更多
As a bio-recalcitrant organic pollutant in paper mill effluent, lignin is generally removed by an advanced oxidation process, such as a TiO2/H2O2 photocatalytic technique under irradiation with ultraviolet light, whic...As a bio-recalcitrant organic pollutant in paper mill effluent, lignin is generally removed by an advanced oxidation process, such as a TiO2/H2O2 photocatalytic technique under irradiation with ultraviolet light, which only accounts for less than 5% of sunlight. Herein, we reported a TiO2/H2O2-based thermally-assisted photocatalytic process that allows lignin to be efficiently degraded under visible/near-infrared light at an elevated temperature. Adsorption of H2O2 on TiO2 nanoparticles and an increase of temperature facilitate the production and separation of charge carriers under near-infrared and visible light irradiation, accelerate carrier transfer at the TiO2-electrolyte interface and promote the production of hydroxyl radicals, A higher level of H2O2 addition results in an increased degradation rate of lignin,while the optimal temperature for the thermally-assisted photodegradation of lignin is 70℃. A charge carrier excitation and transfer process was proposed for the TiO2/H2O2, thermally-assisted photocatalytic process. This work describes a new method for the photodegradation of organic pollutants,such as residual lignin in paper mill effluent, using wide band gap semiconductors under visible and near-infrared light irradiation.展开更多
文摘Post-combustion amine absorption and stripping can remove 90% of the CO2 from power plant flue gas, but systems can reduce electrical output by approximately 30% due to energy requirements for stripping CO2 from solvent and CO2 compression. The CO2 capture energy penalty can be reduced while developing renewable energy technologies by meeting CO2 capture energy requirements with a solar thermal energy system, particularly when electricity demand and prices are the highest. This study presents an initial review of solar thermal technologies for supplying CO2 capture energy, with a focus on high temperature systems. Parabolic troughs and central receivers are technically able to provide energy for CO2 capture. However, the solar system's capital costs would be roughly half that of the base coal-fired plant with CO2 capture, and high electricity prices are required to offset the costs of operating the solar thermal system. For high temperature solar thermal systems, direct electricity generation is likely a more efficient way to use solar energy to replace output lost to CO2 capture energy. However, low temperature solar thermal systems might integrate better with solvent stripping equipment, and more rigorous analysis is required to definitively assess the feasibility of using solar energy for CO2 capture.
基金funded by the National Natural Science Foundation of China (31270625)
文摘As a bio-recalcitrant organic pollutant in paper mill effluent, lignin is generally removed by an advanced oxidation process, such as a TiO2/H2O2 photocatalytic technique under irradiation with ultraviolet light, which only accounts for less than 5% of sunlight. Herein, we reported a TiO2/H2O2-based thermally-assisted photocatalytic process that allows lignin to be efficiently degraded under visible/near-infrared light at an elevated temperature. Adsorption of H2O2 on TiO2 nanoparticles and an increase of temperature facilitate the production and separation of charge carriers under near-infrared and visible light irradiation, accelerate carrier transfer at the TiO2-electrolyte interface and promote the production of hydroxyl radicals, A higher level of H2O2 addition results in an increased degradation rate of lignin,while the optimal temperature for the thermally-assisted photodegradation of lignin is 70℃. A charge carrier excitation and transfer process was proposed for the TiO2/H2O2, thermally-assisted photocatalytic process. This work describes a new method for the photodegradation of organic pollutants,such as residual lignin in paper mill effluent, using wide band gap semiconductors under visible and near-infrared light irradiation.