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In this work, a ternary BiOCl/g-C3N4/Ag2CrO4composite with a dual Z-scheme heterojunction was prepared based on a g-C3N4photocatalyst and applied in the photocatalytic reduction of CO2. The optimal CH4and CO yields of the ternary composite catalyst could be achieved on BOC/CN/ACO-1% with 81.21 and 30.20 μmol g–1for 6 h, respectively, which was considerably enhanced compared to that for pure g-C3N4. The apparent quantum efficiency was achieved to be 2.68% for the BOC/CN/ACO-1% catalyst in the photoreduction of CO2at 420 nm. This performance enhancement resulted from constructing the dual Z-scheme and the improved light response, which had efficient charge migration and an excellent response to sunlight. This study provides a vital reference for developing dual Z-scheme heterojunction catalysts for the photocatalytic reduction of CO2.

The chemical experiment in this study is specifically created for undergraduate students studying energy and the environment. The target of the experiment is for students to comprehend the deactivation mechanism of the Ce/TiO2catalyst by oxides of phosphorus through practical experiments and enhance their knowledge of environmental technologies. More significantly, experiments can enable students to understand the poisoning mechanism of selective catalytic reduction (SCR) catalysts and understand various equipment for developing SCR catalysts. Fly ash containing oxides of phosphorus can deactivate SCR catalysts. The student group investigates and explains the poisoning effect of oxides of phosphorus on the Ce/TiO2catalyst in this study, using experimental and characterization techniques such as BET, XRD, H2-TPR, NH3-TPD, XPS, and DRIFT to support the findings. Then, the students’ grades in the laboratory experiments are determined by their performance in experimental operations, catalyst preparation, SCR activity, and poisoning effect analysis. It is encouraging that with this experiment, students may link their understanding of chemistry with practical operation, motivating them to carry out more research on SCR catalysts.

Photocatalytic CO2reduction (PCO2RR) is regarded as a promising means to mitigate the effects of climate change and current energy shortage. However, photocatalysis is not very effective because of the rapid recombination of photogenerated electron–hole pairs. S-scheme heterojunctions can effectively separate photogenerated carriers and significantly improve the redox ability of photocatalysts. In recent years, S-scheme heterojunction photocatalysts have become a popular topic of research because of their superior photocatalytic performance. This review examines the recent research advancements in S-scheme heterojunction photocatalysts. First, the principle of PCO2RR is briefly introduced. Various types of heterojunctions are introduced, the charge transfer mechanisms and characterization methods of S-scheme heterojunctions are described, and the applications of metal oxides, metal sulfides, and other S-scheme photocatalysts in CO2reduction are discussed and reviewed, respectively. In conclusion, the limitations and prospective directions of S-scheme heterojunction photocatalysts in CO2photoreduction are discussed to provide direction for the design of high-performance S-scheme heterojunction photocatalysts.

Solar-energy-driven CO2hydrogenation is a promising strategy to alleviate the climate crisis. Methane is a desirable derivative of CO2reduction. However, developing a photocatalyst for highly active and selective CH4generation remains challenging. Herein, we report a double Z-scheme Bi3O4Cl/g-C3N4/Cd0.5Zn0.5S photocatalyst for efficient reduction of CO2to CH4. In situ characterization techniques confirmed that the charge migration mechanism in Bi3O4Cl/g-C3N4/Cd0.5Zn0.5S promotes charge separation through double internal electric fields. As a result, the optimized C0.01B0.02C catalyst displayed a formation rate high up to 25.34 μmol g–1h–1and a selectivity of 96.52% of CH4. Moreover, the AQY of CO2conversion on C0.01B0.02C (1.84%) was almost 41 times higher than that of the bare CN. This study provides a novel perspective to develop heterojunction photocatalysts for selective CO2conversion to CH4.

Converting CO2into valuable energy and chemicals is an effective way to solve environmental problems and energy crises. Compared with other CO2conversion methods, electrocatalytic CO2conversion can be combined with clean energy, enhancing its energy efficiency, environmental friendliness, and sustainability; the process can be improved significantly. In recent years, the self-assembly of metal ions/clusters and organic ligands to form crystalline compounds, known as metal–organic frameworks (MOFs), has attracted considerable attention. These materials have gained prominence due to their diverse range of potential applications and distinctive properties. This Review briefly introduces the basic principles of electrocatalytic reduction of CO2and the composition and properties of MOF materials. It summarizes the research progress of MOFs in the field of electrocatalytic CO2reduction from the following aspects: pristine MOF catalysts, MOF-based composites, and MOF-derived electrocatalysts. Finally, the development prospects of MOFs are discussed in combination with the current research status, providing a reference for the development of more efficient and stable MOF electrocatalysts.

Excessive greenhouse gas emissions have led to a series of environmental problems, such as the increasing greenhouse effect, rising sea levels, and melting glaciers at the poles, threatening the global environment for human existence. In view of this, the development of CO2capture technologies with commercialization potential is imperative, as CO2is the primary contributor to greenhouse gases. In recent years, chemical absorption techniques founded on sterically hindered amines, such as 2-amino-2-methyl-1-propanol (AMP), have garnered escalating interest owing to their benefits of large absorption capacity and diminished energy consumption for regeneration as compared to traditional amine-based methods. In this review, the steric hindrance effect of a sterically hindered amine and its reaction mechanism with CO2are reviewed. Subsequently, sterically hindered amine absorbents are classified into four kinds, single amine absorbents, blended amine absorbents, biphasic amine absorbents, and nonaqueous amine absorbents, and recent advancements in investigating the kinetic and thermodynamic characteristics of carbon dioxide sequestration through the utilization of sterically hindered amine sorbents are comprehensively evaluated. Technical-economic analysis and life cycle assessment of the CO2capture processes based on sterically hindered amine absorbents have been comprehensively reviewed. Furthermore, future work for CO2capture technologies based on sterically hindered amines is suggested.

The photocatalytic CO2reduction technology can effectively decrease the CO2content in air while converting CO2into high-value-added chemicals and turning waste into treasure. In this study, Cu2O with a concave cubic structure was fabricated by selective etching, and ZnIn2S4nanosheets were successfully loaded on it uniformly, which significantly elevated its catalytic activity. The maximum CO yield of 9.98 μmol/g/h was obtained on the Z-scheme ZIS/Cu2O-0.3 photocatalyst, which was 3.7 and 4.3 times as high as the bare Cu2O concave cube and ZnIn2S4, respectively. The excellent photocatalytic performance could be attributed to the construction of Z-scheme heterojunction which facilitated the efficient separation of electron–hole pairs, a large specific surface area that provided an abundance of reactive sites, and positive visible light response.

Photoreduction of CO2can effectively alleviate the troublesome global energy crisis and environmental problems by converting CO2into hydrocarbons. Due to the discovery of photocatalysts that can respond to infrared light, the application of full spectrum in photocatalysis has attracted many researchers. This review comprehensively summarizes the progress in CO2photocatalytic reduction based on full-spectrum photocatalytic systems, and the basic theory of photoresponse, the mechanism of photocatalysis and photoreduction of CO2, and the representative photocatalytic materials working under ultraviolet, visible, and infrared irradiation are discussed. The strategies and related mechanisms of realizing full-spectrum photocatalysis are introduced, and the contribution of photoreactors to CO2photocatalytic reduction is also mentioned. Finally, the application prospects of light-driven reactions in CO2reduction are prospected. It is hoped that this review can offer clearer guidance for CO2reduction and construction of full spectrum-driven photocatalyst for efficient photocatalytic CO2reduction in the future.

Constructing heterostructures and designing excellent structures to simulate natural photosynthesis are effective ways to efficiently and selectively convert CO2into products with high energy. Herein, a novel 0D/3D heterostructure composed of Cd0.5Zn0.5S quantum dots and CdIn2S4nano-octahedron was resoundingly fabricated via a simple solvothermal–coprecipitation method. The optimal yields of CO2photoreduction to CO and CH4over the Cd0.5Zn0.5S/CdIn2S4composite material could reach up to 14.07 and 4.23 μmol/g/h, respectively, which was primarily due to the synergistic effect of the 0D/3D heterostructure and unique morphology, thus accelerating the transfer of light-induced carriers. In addition, the as-fabricated composite exhibited excellent stability and weaker photocorrosion. Hence, this work could provide a simple and efficient route for the design and construction of photocatalysts with superior activity for CO2photoreduction.

In this work, an urchinlike W18O49/g-C3N4composite was fabricated via a simple hydrothermal process. The photocatalytic CO2conversion reaction was applied to evaluate the photocatalytic behavior of this catalytic system, and the WOCN-20 wt % heterojunction displayed superior photocatalytic behavior under full spectrum light irradiation, which was 6.46 μmol·h–1·g–1for CO and 3.97 μmol·h–1·g–1for CH4, respectively. Furthermore, in the near-infrared region, the composite photocatalysts also displayed excellent photocatalytic performance. A large number of characterizations and testing measures were carried out to study the components, morphology, and physicochemical properties of W18O49/g-C3N4photocatalyst, which were helpful to exploring and understanding the reasons for the improvement of catalytic performance. The boosted activity resulted from the tight contact between W18O49and g-C3N4and the formation of a Z-scheme heterojunction. The local surface plasmonic resonance (LSPR) of W5+also contributed to the realization of efficient photocatalysis under near-infrared light. The Z-scheme electron transport model could realize the efficient separation of light-induced e––h+pairs and reduce the recombination rate, thereby boosting the CO2photocatalytic reduction process.

In this study, novel Schottky-junction photocatalysts Bi-metal-deposited g-C3N4were constructed via a one-step solvothermal process for photocatalytic CO2reduction under simulated irradiation. The photocatalytic performance illustrated that the nanohybrid catalysts have extreme activity and excellent stability. The maximum CO yield of 3.78 μmol h–1g–1was reached on the BiCN-0.6 hybrid, which was about 3 times as much as that of pure g-C3N4. The phase, microstructure, and optical and photoelectrochemical properties were demonstrated by related characterization methods. The improvement mechanism could be ascribed to the enhanced photon absorption capacity and the decreased recombination rate of photoinduced carriers arising from the Schottky barrier in the system. This work may provide a meaningful approach to enhance the photocatalytic activity through a simple and green strategy.

Nd was used as the modifier to improve the NH3-selective catalytic reduction (SCR) performance of MnOxcatalyst used in NOxabatement. The results of the activity test indicated that MnNdOx-0.1 catalyst displayed remarkable catalytic activity and N2selectivity in the temperature range of 50–300 °C. Characterization results proved the enhanced reducibility and the facilitated NH3and NOxadsorption over MnNdOx-0.1 catalyst, accompanied by the existence of more Mn4+and surface adsorbed oxygen species over its surface. The results of the in situ diffuse reflectance infrared Fourier transform study pointed out that the NH3-SCR reaction over the MnNdOx-0.1 catalyst was mainly under the control of the Langmuir–Hinshelwood mechanism (≤100 °C); when the reaction temperature was over 200 °C, the Eley–Rideal mechanism was dominant. More adsorbed NOxand NH3species over the MnNdOx-0.1 catalyst, along with the activation effect of Nd on the adsorbed reactants, had a facilitation impact on the SCR reaction process over the MnNdOx-0.1 catalyst.

In this study, Bi was used as the modifier to elevate the performance of Ce/TiO2catalyst for selective catalytic reduction (SCR) of NOx with NH3. Experimental results indicated that the CeBi/TiO2catalyst with a Bi/Ce molar ratio of 0.15 exhibited excellent low-temperature SCR performance and SO2/H2O resistance compared with the Ce/TiO2catalyst. Characterization results revealed that the introduction of a proper amount of Bi to Ce/TiO2catalyst could generate more Ce3+and chemisorbed oxygen species on its surface, along with the enhanced reducibility and surface acidity. From the results of an in situ DRIFT study, the formation of more adsorbed NH3and NO2species could be detected, as a result, greatly facilitating the low-temperature NH3–SCR reaction over CeBi/TiO2-0.15 catalyst through the Langmuir–Hinshelwood route.

The conversion of CO2into commercially available chemical fuels is a meaningful strategy for mitigating the greenhouse effect. Photocatalytic CO2reduction is an attractive strategy due to its clean and environmentally friendly properties, and seeking efficient photocatalysts is crucial to accomplish high yield and selectivity of CO2. Metal–organic frameworks (MOFs) are favorable for photocatalytic reactions due to their high specific surface areas and abundant active sites. To facilitate the search for practical, green, and sustainable MOF photocatalysts, this paper summarizes the effects of different preparation processes on the photoresponsiveness and pore structure of MOFs, and describes the challenges of large-scale industrial production in the future. Moreover, the mechanism of MOFs photocatalytic reduction of CO2and the factors affecting the photocatalytic performance were summarized in detail. Based on this, this review focuses on the design of band structure, construction of heterojunction, and design of goal-oriented MOF morphology to propose modification strategies and point out the key to improving photocatalytic performance. Finally, the challenges and application prospects of MOFs in photocatalytic reduction of CO2are further discussed.

The selective catalytic reduction (SCR) of NOxwith ammonia is an effective method to remove NOxfrom stationary and mobile sources. Cerium oxides (CeOx) have been studied extensively as low-temperature SCR catalysts since they manifest prominent oxygen storage capacity in catalysis. This paper reviews the recent progress on the Ce-based catalysts for low-temperature SCR de-NOxwith NH3, including three categories, single CeOx, Ce-based multimetal oxide, and Ce-based multimetal oxides with support. In the section on single CeOx, the reasons for the significant catalytic activity and the function of CeOxin the catalytic reactions are systematically reviewed. For multimetal oxide catalysts, the various roles played by the components of catalysts are summarized from several aspects. In the introduction of supported metal oxide catalysts, according to the type of support, the function of each support in the reaction is analyzed methodically. Additionally, we investigated the reaction mechanism of low-temperature SCR of NOx, including Eley–Rideal (E–R) and Langmuir–Hinshelwood (L–H) mechanisms. Finally, the development outlook and direction of the application of cerium oxide-based catalysts in the field of low-temperature SCR of NOxis prospected.

In this study, MnO2nanotubes, nanowires, and nanoparticles were synthetized by a hydrothermal method, after which the NO removal process with sodium persulfate solution catalyzed by MnO2of different shapes was studied and compared. It could be verified that MnO2nanowires showed the best NO removal efficiency of 91.2% with the catalyst concentration of 0.06 mol/L. As illustrated from the XRD, SEM, TEM, and XPS analysis results, the relatively higher activity of MnO2nanowires could be attributed to its low crystallinity and the presence of more lattice oxygen. The reaction mechanism was further confirmed by using the electron paramagnetic resonance technique, which verified the promotional effect by capturing the signal of hydroxyl (•OH) and sulfate (SO4–•) radicals. Additionally, free radical-quenching experiments also verified the decisive impacts of these two radicals on the removal system, where sulfate (SO4–•) radicals played a major role.

Mn–TiO2catalysts were utilized as an ozonation catalyst for the first time to study the simultaneous catalytic ozonation of Hg0and NO at low flue gas temperatures. BET, SEM–EDS, XRD, XPS, H2-TPR, NOx-TPD and Hg0-TPD were used to characterize the catalysts. The Mn–TiO2catalyst, in which the molar content of metal Mn was 60%, exhibited the best catalytic activities of Hg0and NO oxidation, compared with other Mn–TiO2catalysts. It was found that within the range of experiment, the catalytic ozonation efficiency of Hg0and NO was higher than that of ozonation or catalytic oxidation. The results also showed that the presence of NO gas inhibited the catalytic ozonation of elemental mercury, and the inhibition was enhanced with the NO inlet concentration, while few elemental mercury molecules did promote the catalytic ozonation of NO. The addition of H2O vapor promoted the catalytic ozonation of Hg0and NO. In addition, 0.6Mn–TiO2catalyst demonstrated a good TOS and cyclic stability. The catalytic ozonation of NO and Hg0on Mn–TiO2catalyst likely followed the Langmuir–Hinshelwood mechanism, where the hydroxyl radicals reacted with adjacently adsorbed NO molecules and elemental mercury on catalyst surface.

It is well recognized that both alkali and alkali earth metals have a poisoning effect on selective catalytic reduction (SCR) catalyst. In this study, the different poisoning effects of K and Mg on Mn/TiO2catalyst were investigated. It was found that the deactivation effect of K was much stronger than that of Mg. The effect of K or Mg addition on the physicochemical properties of Mn/TiO2catalyst was investigated based on N2adsorption, XRD, XPS, H2-TPR, NH3-TPD, and NO-TPD techniques. The results indicated that the addition of K or Mg on Mn/TiO2catalyst would decrease its specific area, promote the crystallization of TiO2, and lead to a decrease of Mn4+and surface chemisorbed oxygen. Furthermore, the presence of K or Mg on Mn/TiO2catalyst would lead to the drop of reducibility and the adsorption capacity of NH3and NOx species. In addition, the adsorption behavior of NH3and NOx and their surface reactions over the fresh and poisoned Mn/TiO2catalysts were investigated by in situDRIFT study. It was found that the NH3–SCR reaction over Mn/TiO2–Mg was mainly controlled by the L–H mechanism (≤150 °C) and E–R mechanism (>200 °C), while the NH3–SCR reaction over Mn/TiO2–K mainly followed the E–R pathway. The deactivation of Mn/TiO2–Mg mainly resulted from the inhibited adsorption and oxidation of NO, and the seriously suppressed adsorption of NH3species made a great contribution to the deactivation of Mn/TiO2–K.

The extensive use of fossil fuels in residential and industrial fields has resulted in massive emission of gaseous pollutants, which poses a severe threat to the environment and human health. Consequently, it is critical to develop affordable air cleaning technology, catalytic oxidation is one of the most promising technologies for this purpose. CeO2-based catalysts with special morphologies have aroused widespread attention because of their environmental friendliness, surface binding defects, excellent redox ability, and significant oxygen storage capacity. In addition, the morphologies of these catalysts also modulate the valence state of the element, defect sites, and acid-base properties. Therefore, they have been extensively utilized to reduce air pollutants. In this review, the preparation and application of CeO2-based catalysts with special morphologies, such as hollow, cubic, rod-like, and others, have been summarized, followed by an in-depth examination of the advantages and mechanisms of these catalysts toward eliminating air pollutants. Finally, the challenges associated with the preparation and application of CeO2-based catalysts with special morphologies are presented. We hope to provide some reference for the future design and synthesis of novel CeO2-based catalysts used for the abatement of gas pollutants.

The chemical experiment is designed for undergraduates majoring in chemistry, energy, and environment. The intended purpose is that the students will comprehend the reaction mechanism of photocatalytic reduction of CO2through hands-on experiments and deepen their understanding of sustainable energy technologies. More importantly, the experiment can make students strengthen the understanding of basic theory of photochemistry and become familiar with the operation process of laboratory instruments, such as a photocatalytic reactor and gas chromatograph. The novel graphene quantum dots/NiAl layered double hydroxide (GQDs/NiAl-LDH) composites are prepared by undergraduates, and the photocatalytic activity is investigated through a series of characterizations and tests. Then the reaction mechanism analysis is carried out in the form of group discussion after the experiment. The student’s grade in the laboratory experiment depends on the experimental operation, catalyst synthesis, photocatalytic activity, and mechanism analysis. It is promising that students can organically combine chemistry knowledge with experimental operation through this experiment, so as to encourage them to continue the research related to photocatalytic CO2reduction.

Photocatalytic reduction of CO2into hydrocarbon fuels, utilizing inexhaustible solar energy to simulate natural photosynthesis, is a promising approach to simultaneously alleviate environmental issues and energy crises. Among the developed photocatalysts, bismuth (Bi)-based materials have been extensively applied for photocatalytic CO2reduction due to their unique electronic configuration and excellent physicochemical properties. Various approaches have been investigated to enhance the photocatalytic performance of Bi-based photocatalysts for CO2reduction, among which constructing direct or indirect Z-scheme by coupling Bi-based materials with matching semiconductors is an effective method. In this review, the latest major advancements in the design of high-efficient Bi-based Z-scheme photocatalysts for photocatalytic CO2reduction are summarized, including structural engineering strategies for direct Z-scheme and several patterns of indirect Z-scheme construction. Moreover, the proposed S-scheme structure based on the Z-scheme structure is also briefly discussed. Finally, the current challenges and prospects of the future development of the Bi-based Z-scheme structure for CO2photoreduction are also presented and discussed.

The characteristics of working medium is one of the important factors for organic Rankine cycle.The study is based on the waste heat of power plant,7 kinds working medium are selected,include R245fa, R600, R600a, R601a, R236fa, R236ea and RC318.ORC's thermodynamic cycle characteristics are calculated based on the first law of thermodynamics,then,compared the thermal efficiency,evaporating pressure and power ratio of different working medium.Results show that R245fa and R601a as the ORC system working medium have higher thermal efficiency and power ratio,and lower evaporating pressure than other five working medium,are ideal organic working medium to recycle flue gas waste heat of power plant.Secondly,R600 as system cycle working medium also has relatively good performance,can be the appropriate choice of working medium.

CeO2-Fe3O4/TiO2 and CeO2/TiO2 catalysts were prepared by coprecipitation method, and their activities for selective catalytic reduction of NO with NH3 were investigated. As can be seen from the experimental results, the CeO2-Fe3O4/TiO2 catalyst prepared showed the best SCR activity and SO2 resistance. Based on the characterization results of BET, XRD, NH3-TPD and XPS the excellent performance of CeO2-Fe3O4/TiO2 catalyst should be resulted from its large surface area, high NH3 adsorption capacity and high concentration of surface chemisorbed oxygen.

Life cycle analysis combined with technical economic evaluation method in the paper to control the cost of denitration. A simple model for denitration cost is developed. The influence of different flue gas concentration of NOx to the cost of unit denitration is analysed by life cycle analysis, includes construction, operation and decommissioning, which based on 600 MW coal-fired units. Preliminary calculations reveal that comparing with directly using the denitration technology of selective catalytic reduction (SCR), after using Air staged Low NOx Combustion Technology reduced NOx below 400mg/m3, using SCR denitration further decreased the concentration of NOx in flue gas to 100mg/m3 can save more than 44% of the general denitration cost. This can improve effectively the environmental protection and economy of the coal-fired unit.

This paper used physical modeling method to simulate the running state of each component of the air conditioner, got the ideal conditions of air conditionor energy consumption model and then calibrated and corrected the model of the air conditioner energy consumption by the experimental data. After utilizing the model for the performance analysis of the actual air conditioner, it was found that the extreme outdoor climate would affect the performance of the air conditioner. In summer, the electricity required to produce the same amount of cooling capacity will be 210% compared with 30°C of outdoor temperature, when the outdoor temperature is 50 °C; In winter, the drop of outdoor temperature will seriously impact on the energy efficiency of air conditioner, when the outdoor temperature is-5°C the electricity required to produce the same amount of cooling capacity will be 150% compared with 10 °C of outdoor temperature. It is of great significance that the results shown in this research contributes to the analysis of air conditioner in extreme conditions, and amended energy consumption of the model can not only forecast the performance of household air conditioners under the extreme climate but also indicate the future direction of air conditionersdesign and improvement.

In order to fit in with the demands of the development of electricity market in China, a multi-objective optimization mathematical model is presented to dispatch load within the units, taking economy, environmental protection and quick responsiveness to dispatching commands into consideration at the same time. And take the minimal whole plants power-supply coal cost rate, the minimal pollutant emissions and the minimal load adjusting time as these three objective functions respectively. The four constraint conditions are unit power balance constraint, load bound constraint, ramping constraint and pollution discharge standards constraint. An improved particle swarm optimization algorithm is used to get the Pareto solution set. The optimal solution was obtained by using the method of multi-attribute decision making, through sequencing the solution set by comprehensive evaluation. A case study based on a power plant with 4×600MW units was carried out. The result shows that the method can solve the multi-objective optimal load distribution problem accurately and quickly, and get the good effect in energy conservation and emissions reduction.

In this research, an experimental apparatus that composed of adiabatic packed absorption and regeneration columns was established to simulate H2S removal process. The results show that the reaction between CO2 and MDEA can be regarded as a rapid pseudo-first-order reversible reaction and the CO2 absorption mainly is controlled by liquid film resistance while the reaction between H2S and MDEA are reversible instantaneous. For H2S absorption, it is mainly controlled by gas film resistance but the rate of liquid film resistance to the total resistance of H2S absorption was distributed from 25.7% (column bottom) to 12.6% (column up).

NOx is the main air pollutant of coal-fired power plants, which is one of the important reasons to cause pollution such as acid rain, photochemical smog and so on. Selective catalytic reduction process is the major technology for reducing NOx emissions from coal-fired power plants. However, the commercial vanaidia-based catalyst is active within a narrow temperature window of 300-400°C, easily to be deacticed by SO2 in the flue gas. And the formation of N2O and toxicity of vanaidia cause secondary pollution. Therefore, it is of more importance to develop a new environmental-friendly catalyst for low temperature SCR with high activity.

Cement Precalciner is the important devices in the cement production,also the main part which the pollutants are produced. Hence, it is extremely important to optimize the performance of the precalcine and low NOx emission. This thesis base on the previous article, aim to review of denitration for the cement kilns.

To control mercury pollution has become a major issue nowadays. The SCR systems in power plant can oxide the elemental mercury into oxidized mercury, which can be removed by WFGD, it became a very feasible measures to control mercury pollution. The core part of SCR system is SCR catalyst. The influence of different metal composition and modification of SCR catalyst and the gas composition in simulative flue gas for the efficiency of the conversion of elemental mercury are introduced ,for sifting the catalyst with high efficiency for mercury conversion under the condition of low temperature.

The catalysts of Mn/TiO2, Fe/TiO2 and Mn-Fe/TiO2 prepared by coprecipitation method were investigated for low temperature selective catalytic reduction of NO with NH3. The catalytic activity and SO2 resistance of these three catalysts were tested and the properties of the catalysts were characterized by using N2-BET, XRD, H2-TPR, NH3-TPD methods. It was found that the doping of iron reduced the catalytic activity of Mn/TiO2 catalyst at low temperature and also has an adverse effect for its SO2 resistance at the same time. The decrease of surface area , redox ability and surface acid sites caused by doping of iron might be the main reasons for poor performance of this catalyst.

A major source of PM2.5 is the combustion of coal-fired power plant, so its very necessary to monitor and control the emission of PM2.5 form power plant. This paper summarizes the main emission control technologies of PM2.5 for coal-fired plant. As the traditional electrostatic precipitators has low removal efficiency of submicron particles, so we improved the supply conditions of the precipitator, and pre-charged to improve the particle properties. Through this article, we know that using electric coagulation technology to control the particles form plant is practicable, and it has a good prospect for development.

In this study, Er3+/Yb3+co-doped NiAl-LDH (LDH:Er3+,Yb3+) photocatalysts were successfully fabricated through a solvothermal process. The results revealed that the LDH:Er3+,Yb3+displayed promoted photoreduction CO2activity under Vis/NIR light irradiation. A maximum CO yield of 13.2 μmolg-1h-1had been obtained on LDH:1%Er,2%Yb, which was 9.4 and 1.5 times higher as high as the pure LDH and the LDH:1%Er, respectively. The improved photocatalytic activity can be ascribed to the expanded photoresponse range to NIR light region caused by the upconversion effect of Er3+/Yb3+, and the improved photogenerated charge separation efficiency with Er3+/Yb3+serving as an electron trap. The NIR photocatalytic activity and the improved light absorption of LDH: Er3+,Yb3+indicate that the upconversion mechanism is involved in the whole photocatalytic process. Therefore, this result presents new insights for the rational construction of Vis-NIR light-driven photocatalysts with high-efficient solar energy utilization and practical application prospects in the future.

In this paper, K-means clustering algorithm of data mining technology is applied to determine the targeted value. The historical operation data of 600MW unit boiler are studied to determine the boiler combustion optimization target values of different conditions. The normalized method is used for handling data, directly reflects the position of operation target value in the whole parameter range, provides guide for boiler combustion optimization.

The limestone-lime washing technology is the most widely used WFGD process, which normally we adopt to control the discharge of SO2 caused by coal’s combustion. Through the research on the oxidation kinetics of sulfite in this paper, it is indicated that macroscopic chemical reaction which responses to rate of sulfite is 1/2. And the results of orthogonal test can be concluded that: to the extent influence of oxidization reaction rate, the influences of temperature is the most significant, and influences of stirred speed is nearly negligible. The optimized operation factors may be shown as that temperature is controlled at 40℃, air ventilation is at 88ml/min,pH is 4.5 and stir speed is 500 r/min.

The mercury removal performance of the 150 mesh coal fly ash was evaluated through multiphase flow reactor designed by Shanghai University of Electric Power and different types of fly ash and absorption liquid were analyzed with HYDRA AA. The results showed that UV light almost had no oxidation capacity for gaseous mercury without fly ash, but the removal efficiency was significantly improved from 38.5% to 66.1% in the UV light by adding fly ash into the simulated flue gas. The fly ash after exposure to UV irradiation can improve the removal efficiency of Hg and the capture capacity of oxidized Hg had been greatly enhanced. Most of mercury adsorbed on the surface of fly ash in light conditions was Hg0 (g) and most Hg2+(g) stayed in the simulated flue gas and then was absorbed by absorption liquid.

In order to reduce power plant nitric oxide emission with gaining economical adsorbent, activated carbon was prepared from the raw materials of orange peel under different operating conditions in this paper. The methylene blue adsorption value of different activated carbon has also been tested, and the effects on the methylene blue adsorption performance of different dipping concentration, activation time and carbonization temperature were studied. The finding is that the dipping concentration has the most important impact on methylene blue adsorption value. The highest methylene blue adsorption value of orange peel activated carbon has shown as 277.746mg/g under the following conditions: phosphoric acid concentration was 40%, activation time was 12 hours and carbonization temperature was 500℃. It is a economically feasible absorbent material through a great deal of experiments and analysis.

In order to study the influence of UV irradiation, treat temperature of nano-titanium dioxide and intensity of UV irradiation on the mercury removal performance, experiments were carried out on a photocatalytic oxidization system to find the best experimental conditions. Commercial Degussa P25 was used as a photocatalyst loading on titanium mesh, and the mercury removal efficiency was stable at 8% in the absence of UV irradiation. Under the UV irradiation of 300W mercury lamp, the mercury removal efficiency surged to 100%. With the same light intensity, the same removal time, the mercury removal efficiency of nano-titanium dioxide calcinated at 100℃ reached 92.2% after 0.5h while the mercury removal efficiency of nano-titanium dioxide calcinated at 500℃ reached 93.6%. Intensity of UV irradiation has a positive impact on the mercury removal performance.

In order to be able to directly observe the interior of boiler furnace, which is of high radiation environment, a novel furnace visualization system and robot handling system for coke and slag are proposed in this paper. The developed furnace visualization and robot handling systems can find and clean fouling, slag on the boiler heating surface, improving the unit economics and safety.

In this paper, fly ash samples were collected from a coal-fired power in Shanghai. A series of experiments, including unburned carbon testing, mercury content measurement, SEM analysis, specific surface area, average pore size and pore volume test, were conducted, and the adsorption ability of the fly ash on the flue gas mercury was also experimentally studied. It has shown that fly ash with particle size bigger than 100µm is with the highest adsorption efficiency, 67.83%, and that fly ash with particle size smaller than 25µm is with the smallest adsorption efficiency, 13.67%. The relative mechanism was analyzed.

Describes the theory and methods of data mining technology, and the latest research progress home and abroad. In the equipment operation of various thermal power plants, more and more field data is stored in the DCS real-time database, and there is always an abundance of knowledge hidden behind the data. Adopting the date mining technology to process and analyze these data can optimize the operation of power plants and provide effective means for monitoring and evaluation of the equipment.

Fluctuating wind speed spectrum, which is closer to the actual working conditions, was simulated by davenport wind speed model, and displacement and stress distribution of blade under fluctuating wind speed were calculated by finite element analysis software. The numerical results indicate that the growth trend of vibration amplitude for whole blade at flapping direction is nonlinear along the wingspan. The max von-mises stress appears when the vibration amplitude of tip reaches the maximum, and it is mainly concentrated in the central part of the blade. The stress at trailing edge and tip is smaller than the central part. Above results provide a reference for the strength safety design of wind turbine blade.,Fluctuating wind speed spectrum, which is closer to the actual working conditions, was simulated by davenport wind speed model, and displacement and stress distribution of blade under fluctuating wind speed were calculated by finite element analysis software. The numerical results indicate that the growth trend of vibration amplitude for whole blade at flapping direction is nonlinear along the wingspan. The max von-mises stress appears when the vibration amplitude of tip reaches the maximum, and it is mainly concentrated in the central part of the blade. The stress at trailing edge and tip is smaller than the central part. Above results provide a reference for the strength safety design of wind turbine blade.

Cold vapor atomic adsorption spectrometry method was used in measuring mercury content in human’s hair samples after comparing the mercury measurement methods. Aqua regia-hydrofluoric acid digestion was taken to pretreat hair samples, and then mercury volume can be attained by Hydra AA Automatic mercury analyzer. Mercury concentration in about 40 percent of the tested samples exceeded the U.S. EPA recommended level 1μg/g. The results were analyzed from different respects including living environments, age distribution and dietary habits, and so on. The experimental data can supply a possible proof of mercury pollution in the studied district, and build foundation for the following full-scale mercury pollution investigation.

The mercury concentration in the coals from Datong and Xiaoyi, Shanxi has been measured to study the relationship between mercury enrichment in coal and coalseam depth. Ten samples were researched, of which 7 coal and rock samples from the main coalseam and the places around it were collected at a miner in Datong city, and 3 coal samples from three coalseams at a miner in Xiaoyi city. The mercury concentration in the coal and rock samples was measured with US EPA Method7471, which is a standard method recommended by the US EPA. The results show that the mercury enrichment in coal is higher than that in rock in the same conditions, and the mercury concentration in the longer-buried coal is higher than that of the shorter-buried. However, the mercury concentration in coal with depth has no definite linear correlation, varying in different coal fields.