COphotoreduction is an attractive process which allows the storage of solar energy and synthesis of solar fuels. Many different photocatalytic systems have been developed, while the alternative photo-reactors are stil...COphotoreduction is an attractive process which allows the storage of solar energy and synthesis of solar fuels. Many different photocatalytic systems have been developed, while the alternative photo-reactors are still insufficiently investigated. In this work, photoreduction of COwith HO into CHwas investigated in a modified concentrating solar reactor, using TiOand Pt/TiOas the catalysts. The TiOand Pt/TiOsamples were extensively characterized by different techniques including powder X-ray diffraction（XRD）, Nadsorption/desorption and UV–vis absorption. The catalytic performance of the TiOand Pt/TiOsamples in the gas phase was evaluated under unconcentrated and concentrated Xe-lamp light and nature solar light with different concentrating ratios. Various parameters of the reaction system and the catalysts were investigated and optimized to maximize the catalytic performance of COreduction system. Compared with the normal light irradiation, the TiOand Pt/TiOsamples show higher photocatalytic activity（about 6–7 times） for reducing COinto CHunder concentrated Xe-lamp light and nature solar light. In the range of experimental light intensity, it is found that the concentration of the light makes it suitable for the catalytic reaction, and increases the utilization efficiency of the TiOand Pt/TiOsamples while does not decrease the quantum efficiency.展开更多
Over exploitation of non-renewable energy reserves will lead to increase in price of petroleum fuels.Therefore there is a need for suitable and sustainable substitutes(renewable resource) for conventional fuels.In thi...Over exploitation of non-renewable energy reserves will lead to increase in price of petroleum fuels.Therefore there is a need for suitable and sustainable substitutes(renewable resource) for conventional fuels.In this study,an efficient and environmental friendly method for production of bio-diesel from Pongamia(Karanja) oil has been developed using a solar reactor.During the experimental study,the maximum temperature attained by the pongamia oil during the transesterification process was 64.1℃.The transesterification reaction was studied by varying different parameters such as reactant flow rate(5-20 L·h^(-1)),stirring speed(150-450 r·min^(-1)),catalyst mass loading(0.5%-2%) and methanol to oil ratio(3:1 to15:1).The maximum biodiesel yield was 83.11% at a flow rate of 5 L·h^(-1),stirring speed of 350 r·min^(-1),a methanol to oil ratio of 15:1,catalyst mass loading of 1% and reaction time of 270 min.The physical and chemical properties of biodiesel was analyzed as per American Society for Testing Materials(ASTM) standards and it had density of 938 kg·m^(-3),viscosity(28.7×10^(-6) m~2·s^(-1)),acid value(9.45 mg KOH·(g oil)^(-1))and flash point(215℃).The energy efficiency of solar heating process was determined by comparing the net energy ratio of direct heating process and solar heating process.For solar heating the net energy ratio(NER) was found to be 31.85 against 5.73 for direct heating.Similarly,net energy efficiency index was calculated for 10 kg production scale and was found to be increasing when scaled up which means that the solar heating process is more effective even in scaled up production.展开更多
Solar fuels can be cost-effectively produced using solar-driven thermochemical processes.Hybridizing thermochemical processes can not only effectively utilize solar energy but also achieve clean conversion of fossil f...Solar fuels can be cost-effectively produced using solar-driven thermochemical processes.Hybridizing thermochemical processes can not only effectively utilize solar energy but also achieve clean conversion of fossil fuels.With this method,the solar energy level can be upgraded,and the irradiation fluctuation can be solved.It is worth noting that solar reactors play an important role in this technology.In this study,we demonstrated a 10-kW parabolic trough solar-driven reactor prototype for methane reforming and solar fuel production.The primary setup of the experimental platform consisted of a trough concentrating solar collector,chemical looping reforming reactors with indirect heat transfer,and associated auxiliary equipment.Experiments on the chemical looping redox cycle were conducted using nickel-based NiO/NiAl_(2)O_(4)as the OC under different direct normal irradiation(DNI)from 740 to 920 W/m^(2).Under irradiation at approximately 920 W/m^(2),the methane conversion initially increased to 92%before declining to 75%from 0 to 900 s and then to 2500 s.Under these conditions,the syngas concentration increased from 30%to 57%and the solar-to-fuel efficiency reached 59%.The oxygen transfer rate during the chemical looping redox cycle was also experimentally investigated.Cyclic redox cycle experiments were conducted for 540 min of long-term operation to assess the duration and adaptability performance.The fractional oxidation can consistently return to almost 1.0 after each redox cycle,indicating strong reactivity and regenerability when exposed to different levels of DNI.The reactivity of the chemical looping redox cycle during typical autumn and winter days was also investigated and discussed.This study aimed to prove that this 10-kW parabolic trough reactor prototype can harness 500℃solar heat to drive efficient methane reforming,offering a promising avenue for solar fuel production.展开更多
The thermal pyrolysis of natural gas as a clean hydrogen production route is examined. The concept of a double-walled reactor tube is proposed and implemented. Preliminary experiments using an external plasma heating ...The thermal pyrolysis of natural gas as a clean hydrogen production route is examined. The concept of a double-walled reactor tube is proposed and implemented. Preliminary experiments using an external plasma heating source are carried out to validate this concept. The results point out the efficient CH4 dissociation above 1850 K （CH4 conversion over 90%） and the key influence of the gas residence time. Simulations are performed to predict the conversion rate of CH4 at the reactor outlet, and are consistent with experimental tendencies. A solar reactor prototype featuring four independent double-walled tubes is then developed. The heat in high temperature process required for the endothermic reaction of natural gas pyrolysis is supplied by concentrated solar energy. The tubes are heated uniformly by radiation using the blackbody effect of a cavity-receiver absorbing the concentrated solar irradiation through a quartz window. The gas composition at the reactor outlet, the chemical conversion of CH4, and the yield to H2 are determined with respect to reaction temperature, inlet gas flow-rates, and feed gas composition. The longer the gas residence time, the higher the CH4 conversion and H2 yield, whereas the lower the amount of acetylene. A CH4 conversion of 99% and H2 yield of about 85% are measured at 1880 K with 30% CH4 in the feed gas （6 L/min injected and residence time of 18 ms）, A temperature increase from 1870 K to 1970 K does not improve the H2 yield.展开更多
Heat transfer and thermochemical energy storage process of methane dry reforming in a disk reactor with focused solar simulator was modeled and analyzed. The results showed that thermochemical energy storage efficienc...Heat transfer and thermochemical energy storage process of methane dry reforming in a disk reactor with focused solar simulator was modeled and analyzed. The results showed that thermochemical energy storage efficiency of disk reactor can reach 28.4%, and that is higher than that of tubular reactor.?The maximum reaction rate occurs at catalyst bed corner near the baffle, because the corner has high temperature and high reactant molar fraction. As reactant flow increases, methane conversion and thermochemical energy storage efficiency decrease as catalyst bed temperature and heat loss decrease.?The?thermochemical energy storage efficiency increased first and then decreased with methane molar ratio increasing, while?methane conversion?and the?thermochemical energy storage efficiency increased with reactant temperature increasing.?As catalyst bed porosity rises,?methane conversion?and?thermochemical energy storage efficiency increased first and then decreased, and optimum porosity is 0.31.展开更多
The developed Hypersphere World-Universe Model (WUM) is consistent with all Concepts of the World [1]. In WUM, we postulate the principal role of Angular Momentum and Dark Matter in Cosmological theories of the World....The developed Hypersphere World-Universe Model (WUM) is consistent with all Concepts of the World [1]. In WUM, we postulate the principal role of Angular Momentum and Dark Matter in Cosmological theories of the World. The most widely accepted model of Solar System formation, known as the Nebular hypothesis, does not solve the Angular Momentum problem—why is the orbital momentum of Jupiter larger than rotational momentum of the Sun? WUM is the only cosmological model in existence that is consistent with this Fundamental Law. The Nebular hypothesis does not solve Internal Heating and Diversity problems for all Planets and Moons in Solar system—why the actual mean surface temperature of them is higher than their effective temperature calculated based on the Sun’s heat for them and how could each one be so different if all of them came from the same nebula? The proposed concept of Dark Matter Reactors in Cores of all gravitationally-rounded Macroobjects successfully resolves these problems.展开更多
This work provides information for an optimal design of a thermochemical storage system, through a proposed mathematical model that predicts the behavior of a solar fluidized bed receiver finding the temperature and c...This work provides information for an optimal design of a thermochemical storage system, through a proposed mathematical model that predicts the behavior of a solar fluidized bed receiver finding the temperature and concentration profiles in transient state. The mathematical model is developed for a fluidized bed solar reactor, taking into account dynamics conditions of heating and reaction. The heating was simulated for radiated flux with a normal distribution over lateral walls and with distributed flow conditions of the focal stain. The contraction and expansion effects of the bed were involved with a two dimensional distribution. The mathematical model of a solar fluidized bed reactor involves a reversible chemistry reaction of thermal dissociation of the zinc sulfate （ZnSO4）, also the mathematical model is accomplished by a sensitivity study with regard to the gas inlet temperature and radiation flux.展开更多
This article reports an innovative integrated system utilizing solar energy as power for decentralized wastewater treatment, which consists of an oxidation ditch with double channels and a photovoltaic （PV） system w...This article reports an innovative integrated system utilizing solar energy as power for decentralized wastewater treatment, which consists of an oxidation ditch with double channels and a photovoltaic （PV） system without a storage battery. Because the system operates without a storage battery, which can reduce the cost of the PV system, the solar radiation intensity affects the amount of power output from the PV system. To ensure that the power output is sufficient in all different weather conditions, the solar radiation intensity of 78 W/m 2 with 95% confidence interval was defined as a threshold of power output for the PV system according to the monitoring results in this study, and a step power output mode was used to utilize the solar energy as well as possible. The oxidation ditch driven by the PV system without storage battery ran during the day and stopped at night. Therefore, anaerobic, anoxic and aerobic conditions could periodically appear in the oxidation ditch, which was favorable to nitrogen and phosphate removal from the wastewater. The experimental results showed that the system was efficient, achieving average removal efficiencies of 88% COD, 98% NH 4 ＋ -N, 70% TN and 83% TP, under the loading rates of 140 mg COD/（g MLSS·day）, 32 mg NH 4 ＋ -N/（g MLSS·day）, 44 mg TN/（g MLSS·day） and 5 mg TP/（g MLSS·day）.展开更多
The most widely accepted model of Solar System formation, known as the Nebular hypothesis, does not solve the Angular Momentum problem—why is the orbital momentum of Jupiter larger than rotational momentum of the Sun...The most widely accepted model of Solar System formation, known as the Nebular hypothesis, does not solve the Angular Momentum problem—why is the orbital momentum of Jupiter larger than rotational momentum of the Sun? The present manuscript introduces a Rotational Fission model of creation and evolution of Macrostructures of the World (Superclusters, Galaxies, Extrasolar Systems), based on Overspinning Cores of the World’s Macroobjects, and the Law of Conservation of Angular Momentum. The Hypersphere World-Universe model is the only cosmological model in existence that is consistent with this Fundamental Law.展开更多
A new theoretical prediction that a plasma can produce antineutrinos is used to solve the solar neutrino problem. The difference between electron-positron induced fusion, and inertial fusion experiments that have been...A new theoretical prediction that a plasma can produce antineutrinos is used to solve the solar neutrino problem. The difference between electron-positron induced fusion, and inertial fusion experiments that have been unsuccessful so far as commercial fusion reactors is also discussed.展开更多
Solar-driven biomass gasification is a promising approach for producing renewable fuels such as green hydrogen.Catalysts are a potential pathway for enhancing the performance of gasification technologies;however,tradi...Solar-driven biomass gasification is a promising approach for producing renewable fuels such as green hydrogen.Catalysts are a potential pathway for enhancing the performance of gasification technologies;however,traditional catalytic methods still focus on improving the performance of autothermal gasification.To support the expansion of catalytic technology to solar gasification,this study was aimed at investigating the characteristics and mechanisms of traditional catalysts under solar irradiation in the absence of oxygen.Four types of catalysts were experimentally studied for their comprehensive thermochemical properties in solar-driven straw biomass gasification using a newly developed direct-irradiation fixed-bed reactor.The prototype design achieved a maximum bed temperature of 1260°C with an average solar irradiance flux density of 1171.3 kW/m2.Compared to non-catalytic processes,the use of catalysts has led to varying degrees of improvement in syngas yield.The H2yield of the syngas catalyzed by CaO reached 49.50%,which was 3.44%higher than that of the non-catalytic syngas.Compared with non-catalytic conditions,CaMg(CO3)2,Fe2O3,Na2CO3,and CaO significantly enhanced the energy upgrade factor of gasification.The energy upgrade factor of gasification catalyzed by CaMg(CO3)2notably increased to 1.08,with a molar H2/CO ratio of 0.87.Additionally,microanalysis of solid residues revealed partial transformation and morphological damage of the catalysts under solar irradiation.Integrated catalytic experiments on solar gasification provide new avenues and rich foundational data for intensification and regulation of gasification products.展开更多
文摘COphotoreduction is an attractive process which allows the storage of solar energy and synthesis of solar fuels. Many different photocatalytic systems have been developed, while the alternative photo-reactors are still insufficiently investigated. In this work, photoreduction of COwith HO into CHwas investigated in a modified concentrating solar reactor, using TiOand Pt/TiOas the catalysts. The TiOand Pt/TiOsamples were extensively characterized by different techniques including powder X-ray diffraction（XRD）, Nadsorption/desorption and UV–vis absorption. The catalytic performance of the TiOand Pt/TiOsamples in the gas phase was evaluated under unconcentrated and concentrated Xe-lamp light and nature solar light with different concentrating ratios. Various parameters of the reaction system and the catalysts were investigated and optimized to maximize the catalytic performance of COreduction system. Compared with the normal light irradiation, the TiOand Pt/TiOsamples show higher photocatalytic activity（about 6–7 times） for reducing COinto CHunder concentrated Xe-lamp light and nature solar light. In the range of experimental light intensity, it is found that the concentration of the light makes it suitable for the catalytic reaction, and increases the utilization efficiency of the TiOand Pt/TiOsamples while does not decrease the quantum efficiency.
文摘Over exploitation of non-renewable energy reserves will lead to increase in price of petroleum fuels.Therefore there is a need for suitable and sustainable substitutes(renewable resource) for conventional fuels.In this study,an efficient and environmental friendly method for production of bio-diesel from Pongamia(Karanja) oil has been developed using a solar reactor.During the experimental study,the maximum temperature attained by the pongamia oil during the transesterification process was 64.1℃.The transesterification reaction was studied by varying different parameters such as reactant flow rate(5-20 L·h^(-1)),stirring speed(150-450 r·min^(-1)),catalyst mass loading(0.5%-2%) and methanol to oil ratio(3:1 to15:1).The maximum biodiesel yield was 83.11% at a flow rate of 5 L·h^(-1),stirring speed of 350 r·min^(-1),a methanol to oil ratio of 15:1,catalyst mass loading of 1% and reaction time of 270 min.The physical and chemical properties of biodiesel was analyzed as per American Society for Testing Materials(ASTM) standards and it had density of 938 kg·m^(-3),viscosity(28.7×10^(-6) m~2·s^(-1)),acid value(9.45 mg KOH·(g oil)^(-1))and flash point(215℃).The energy efficiency of solar heating process was determined by comparing the net energy ratio of direct heating process and solar heating process.For solar heating the net energy ratio(NER) was found to be 31.85 against 5.73 for direct heating.Similarly,net energy efficiency index was calculated for 10 kg production scale and was found to be increasing when scaled up which means that the solar heating process is more effective even in scaled up production.
基金supported by the National Natural Science Foundation of China(Grant No.52306242)Beijing Natural Science Foundation(Grant No.Z210016)the China Postdoctoral Science Foundation(Grant No.2022M711132)。
文摘Solar fuels can be cost-effectively produced using solar-driven thermochemical processes.Hybridizing thermochemical processes can not only effectively utilize solar energy but also achieve clean conversion of fossil fuels.With this method,the solar energy level can be upgraded,and the irradiation fluctuation can be solved.It is worth noting that solar reactors play an important role in this technology.In this study,we demonstrated a 10-kW parabolic trough solar-driven reactor prototype for methane reforming and solar fuel production.The primary setup of the experimental platform consisted of a trough concentrating solar collector,chemical looping reforming reactors with indirect heat transfer,and associated auxiliary equipment.Experiments on the chemical looping redox cycle were conducted using nickel-based NiO/NiAl_(2)O_(4)as the OC under different direct normal irradiation(DNI)from 740 to 920 W/m^(2).Under irradiation at approximately 920 W/m^(2),the methane conversion initially increased to 92%before declining to 75%from 0 to 900 s and then to 2500 s.Under these conditions,the syngas concentration increased from 30%to 57%and the solar-to-fuel efficiency reached 59%.The oxygen transfer rate during the chemical looping redox cycle was also experimentally investigated.Cyclic redox cycle experiments were conducted for 540 min of long-term operation to assess the duration and adaptability performance.The fractional oxidation can consistently return to almost 1.0 after each redox cycle,indicating strong reactivity and regenerability when exposed to different levels of DNI.The reactivity of the chemical looping redox cycle during typical autumn and winter days was also investigated and discussed.This study aimed to prove that this 10-kW parabolic trough reactor prototype can harness 500℃solar heat to drive efficient methane reforming,offering a promising avenue for solar fuel production.
基金European FP6 research project SOLHYCARB (Contract SES-CT-2006-19770)
文摘The thermal pyrolysis of natural gas as a clean hydrogen production route is examined. The concept of a double-walled reactor tube is proposed and implemented. Preliminary experiments using an external plasma heating source are carried out to validate this concept. The results point out the efficient CH4 dissociation above 1850 K （CH4 conversion over 90%） and the key influence of the gas residence time. Simulations are performed to predict the conversion rate of CH4 at the reactor outlet, and are consistent with experimental tendencies. A solar reactor prototype featuring four independent double-walled tubes is then developed. The heat in high temperature process required for the endothermic reaction of natural gas pyrolysis is supplied by concentrated solar energy. The tubes are heated uniformly by radiation using the blackbody effect of a cavity-receiver absorbing the concentrated solar irradiation through a quartz window. The gas composition at the reactor outlet, the chemical conversion of CH4, and the yield to H2 are determined with respect to reaction temperature, inlet gas flow-rates, and feed gas composition. The longer the gas residence time, the higher the CH4 conversion and H2 yield, whereas the lower the amount of acetylene. A CH4 conversion of 99% and H2 yield of about 85% are measured at 1880 K with 30% CH4 in the feed gas （6 L/min injected and residence time of 18 ms）, A temperature increase from 1870 K to 1970 K does not improve the H2 yield.
文摘Heat transfer and thermochemical energy storage process of methane dry reforming in a disk reactor with focused solar simulator was modeled and analyzed. The results showed that thermochemical energy storage efficiency of disk reactor can reach 28.4%, and that is higher than that of tubular reactor.?The maximum reaction rate occurs at catalyst bed corner near the baffle, because the corner has high temperature and high reactant molar fraction. As reactant flow increases, methane conversion and thermochemical energy storage efficiency decrease as catalyst bed temperature and heat loss decrease.?The?thermochemical energy storage efficiency increased first and then decreased with methane molar ratio increasing, while?methane conversion?and the?thermochemical energy storage efficiency increased with reactant temperature increasing.?As catalyst bed porosity rises,?methane conversion?and?thermochemical energy storage efficiency increased first and then decreased, and optimum porosity is 0.31.
文摘The developed Hypersphere World-Universe Model (WUM) is consistent with all Concepts of the World [1]. In WUM, we postulate the principal role of Angular Momentum and Dark Matter in Cosmological theories of the World. The most widely accepted model of Solar System formation, known as the Nebular hypothesis, does not solve the Angular Momentum problem—why is the orbital momentum of Jupiter larger than rotational momentum of the Sun? WUM is the only cosmological model in existence that is consistent with this Fundamental Law. The Nebular hypothesis does not solve Internal Heating and Diversity problems for all Planets and Moons in Solar system—why the actual mean surface temperature of them is higher than their effective temperature calculated based on the Sun’s heat for them and how could each one be so different if all of them came from the same nebula? The proposed concept of Dark Matter Reactors in Cores of all gravitationally-rounded Macroobjects successfully resolves these problems.
文摘This work provides information for an optimal design of a thermochemical storage system, through a proposed mathematical model that predicts the behavior of a solar fluidized bed receiver finding the temperature and concentration profiles in transient state. The mathematical model is developed for a fluidized bed solar reactor, taking into account dynamics conditions of heating and reaction. The heating was simulated for radiated flux with a normal distribution over lateral walls and with distributed flow conditions of the focal stain. The contraction and expansion effects of the bed were involved with a two dimensional distribution. The mathematical model of a solar fluidized bed reactor involves a reversible chemistry reaction of thermal dissociation of the zinc sulfate （ZnSO4）, also the mathematical model is accomplished by a sensitivity study with regard to the gas inlet temperature and radiation flux.
基金supported by the National Natural Science Foundation of China (No.51138009, 50678170)
文摘This article reports an innovative integrated system utilizing solar energy as power for decentralized wastewater treatment, which consists of an oxidation ditch with double channels and a photovoltaic （PV） system without a storage battery. Because the system operates without a storage battery, which can reduce the cost of the PV system, the solar radiation intensity affects the amount of power output from the PV system. To ensure that the power output is sufficient in all different weather conditions, the solar radiation intensity of 78 W/m 2 with 95% confidence interval was defined as a threshold of power output for the PV system according to the monitoring results in this study, and a step power output mode was used to utilize the solar energy as well as possible. The oxidation ditch driven by the PV system without storage battery ran during the day and stopped at night. Therefore, anaerobic, anoxic and aerobic conditions could periodically appear in the oxidation ditch, which was favorable to nitrogen and phosphate removal from the wastewater. The experimental results showed that the system was efficient, achieving average removal efficiencies of 88% COD, 98% NH 4 ＋ -N, 70% TN and 83% TP, under the loading rates of 140 mg COD/（g MLSS·day）, 32 mg NH 4 ＋ -N/（g MLSS·day）, 44 mg TN/（g MLSS·day） and 5 mg TP/（g MLSS·day）.
文摘The most widely accepted model of Solar System formation, known as the Nebular hypothesis, does not solve the Angular Momentum problem—why is the orbital momentum of Jupiter larger than rotational momentum of the Sun? The present manuscript introduces a Rotational Fission model of creation and evolution of Macrostructures of the World (Superclusters, Galaxies, Extrasolar Systems), based on Overspinning Cores of the World’s Macroobjects, and the Law of Conservation of Angular Momentum. The Hypersphere World-Universe model is the only cosmological model in existence that is consistent with this Fundamental Law.
文摘A new theoretical prediction that a plasma can produce antineutrinos is used to solve the solar neutrino problem. The difference between electron-positron induced fusion, and inertial fusion experiments that have been unsuccessful so far as commercial fusion reactors is also discussed.
基金supported by the National Natural Science Foundation of China(Grant Nos.52176030,52225601)the Shandong Provincial Natural Science Foundation of China(Grant No.ZR2022YQ58)the Taishan Scholars Program of Shandong Province(Grant No.tsqn202312115)。
文摘Solar-driven biomass gasification is a promising approach for producing renewable fuels such as green hydrogen.Catalysts are a potential pathway for enhancing the performance of gasification technologies;however,traditional catalytic methods still focus on improving the performance of autothermal gasification.To support the expansion of catalytic technology to solar gasification,this study was aimed at investigating the characteristics and mechanisms of traditional catalysts under solar irradiation in the absence of oxygen.Four types of catalysts were experimentally studied for their comprehensive thermochemical properties in solar-driven straw biomass gasification using a newly developed direct-irradiation fixed-bed reactor.The prototype design achieved a maximum bed temperature of 1260°C with an average solar irradiance flux density of 1171.3 kW/m2.Compared to non-catalytic processes,the use of catalysts has led to varying degrees of improvement in syngas yield.The H2yield of the syngas catalyzed by CaO reached 49.50%,which was 3.44%higher than that of the non-catalytic syngas.Compared with non-catalytic conditions,CaMg(CO3)2,Fe2O3,Na2CO3,and CaO significantly enhanced the energy upgrade factor of gasification.The energy upgrade factor of gasification catalyzed by CaMg(CO3)2notably increased to 1.08,with a molar H2/CO ratio of 0.87.Additionally,microanalysis of solid residues revealed partial transformation and morphological damage of the catalysts under solar irradiation.Integrated catalytic experiments on solar gasification provide new avenues and rich foundational data for intensification and regulation of gasification products.
