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The feasibility of removal of sulfate ions from the sodium alkali FGD wastewater using the ettringite precipitation method was evaluated. Factors affecting the removal of sulfate ions, such as NaAlO2 dosage, Ca(OH)2 dosage, solution temperature, anions (Cl−, NO3− and F−), and heavy metal ions (Mg2+ and Mn2+), were investigated, and the optimal experimental conditions for the removal of sulfate ions were determined. Experimental results indicate that the ettringite precipitation method can effectively remove SO42− with removal efficiency of more than 98%. All the investigated factors have influences on the removal of sulfate ions, and among them, the dosage of reagents, solution temperature, and fluoride ions have the strongest influence. In addition, the method can effectively synergistically remove F− and heavy metal ions with removal efficiencies of more than 90% and 99%, respectively; meanwhile, Cl− and NO3− also can be removed minimally by the method. The result of actual wastewater treatment shows that the method is feasible for treating high-concentration sulfate wastewater. The ettringite precipitation method has the potential to be a commercial application in the future.

The influences of sludge feed rate, feed point, feed method, and air-staged combustion were systematically investigated in a Chinese cement plant with emphasis on NOX removal. Results indicate that the use of sludge as a secondary fuel is conducive to NOX reduction, which depends primarily on the feed rate and feed point. Moreover, both feed method and air-staged combustion influence NOX removal to some extent. Nonetheless, these factors have little effects on CO removal. When the sludge feed rate is 9 t·h− 1 in a precalciner reburning zone in the combustion temperature range from 850 to 1000 °C, NOX removal reached 75.82% in the air-staged combustion condition. The NOX concentration easily met the national emission standards. Finally, the use of sludge as alternative fuel does not affect clinker quality negatively. This method utilizes sludge effectively and reduces NOX emissions; hence, the application of sewage sludge as a denitration agent and secondary fuel in cement production is a worthy option.

Since the end of the last century, heritage damage caused by inappropriate tourism development in China has occurred constantly in practice. Property rights economics suggests that an institution of property rights plays a key role in property conservation and utilisation. Cultural and natural heritage actually comprise a kind of peculiar scarce property. Therefore, the institution of property rights is crucial for heritage conservation and tourism development. The 30-year tourism history of the Wulingyuan World Heritage Site demonstrates that the heritage damage occurring in China is mainly caused by its present institution of property rights for heritage. Thus, sustainable tourism is the logical choice for solving the conflicts between tourism development and heritage conservation. To achieve this goal, further reform of the present institution of property rights for heritage in China should be prioritised, aimed at establishing clear definition, independent government regulation, and efficient ...

Nitrogen oxides (NOX) are one of the main sources of pollution causing atmospheric pollution, and one of the main causes of acid rain and acid mist. In this paper, low temperature SCR catalysts were prepared by impregnation method. The preparation process and the denitrification rate are optimized by changing the ratio of manganese nitrate and lanthanum nitrate, calcination temperature, carrier, citric acid and the like. At the same time, the physical properties and structural characterization of the catalyst were carried out by SEM and BET. The results showed that the best support was ZSM-5, the loading amount was 14% manganese nitrate, 7% cerium nitrate, citric acid was 1 g, and the calcination temperature was 500 °C.

MOF-5 crystals were prepared by solvothermal synthesis, and characterized by electron microscopy (SEM), X-ray powder diffraction (XRD), and specific surface area (BET). The adsorption of formaldehyde, acetone, glycerol and toluene were studied. The effects of reaction solvent ratio, adsorption time and synthesis temperature on adsorption were investigated. The results show that the reaction solvent ratio is 2.6, the crystal particles have good integrity, the cracking phenomenon and aggregation phenomenon are less, the size is more uniform, highly crystalline, the specific surface area and pore volume are larger, and the pore size distribution is more concentrated. The adsorption time is 48 h, the synthesis temperature is 95°C. Under high temperature conditions, MOF-5 has a high-dimensional skeleton crystal structure with higher specific surface area and pore volume. MOF-5 has the best adsorption effect on toluene.

With the development of a new round of science and technology (S&T) revolution and industrial transformation in the world, the complexity of S&T decision-making is increasing. It not only needs the comprehensive participation of scientific, technological, economic, educational and other social factors but also an effective consultation system to guarantee. To build an effective consultation system for S&T decision-making, a lot of measures can be taken, such as establishing the system of the policy and regulation, perfecting the multi-mode operation system, constructing the support system of talent team, developing of multi-channel financing system, optimizing the system of social public participation and strengthening the system of interactive international cooperation.

article i nfo 0 Absorption A complex absorbent containing urea and KMnO4 was used to investigate simultaneous removal of SO2 ,N O and Hg 0 from flue gas. By focusing on NO, SO2 and Hg 0 removal efficiencies, the influences of different types of oxidants, urea concentration, KMnO4 concentration, Hg 0 inlet concentration, initial pH, reaction tempera- ture, SO2 and NO concentrations were systematically investigated. The results indicate that urea+KMnO4 so- lution cleaned up SO2 quite efficiently; the removal efficiency was more than 98%, and slightly affected by reaction conditions. NO and Hg 0 removal efficiencies depended primarily on the KMnO4 concentration. Urea concentration, reaction temperature, initial solution pH, SO2 and NO concentrations all had a strong in- fluence on the NO removal, but had a little influence on the Hg 0 removal. The inlet concentrations of Hg 0 con- tributed little to the removal of NO and Hg 0 . Meanwhile the optimal conditions were established, the absorption capacities of NO, SO2 and Hg 0 were calculated and the final reaction products in the solution were analyzed under the optimal conditions. This process is a promising method for the simultaneous remov- al of NO, SO2 and Hg 0 .

A new paraffin/surfactant/water emulsion (PSW) for volatile organic compounds (VOCs) controlling was prepared and its potential for VOCs removal was investigated. Results indicated that PSW-5 (5%, v/v) provided higher toluene absorption efficiency (90.77%) than the other absorbents used. The saturation pressure, Henry’s constant, and activity coefficient of toluene in PSW-5 were significantly lower than those in water, and toluene solubility (1.331 g·L−1) in the PSW-5 was more than 2.5 times higher than the value in water. Several factors potentially affecting the toluene absorption efficiency were systematically investigated. The results suggested that concentration and pH of PSW, absorption temperature, and gas flow rate all had a strong influence on the toluene absorption, but the inlet concentration of toluene had little effect on the toluene absorption. There were different absorbing performances of PSW-5 on different VOCs, and the ketones, esters, and aromatics were more easily removed by the PSW-5 than the alkanes. Regeneration and reuse of the PSW were possible; after 3 runs of regeneration the absorption efficiency of PSW-5 for toluene also could reach 82.42%. So, the PSW is an economic, efficient, and safe absorbent and has a great prospect in organic waste gas treatment.

In this study, an experimental apparatus of oxidation + absorption columns was set up to investigated ClO2 and Cl2 emission characteristics when NaClO2 was used as oxidant. Two sets of experiments were designed and compared, one was sampled every 15 min for 2 h and the other one was continuous sampling for 2 h. The results show that the concentration of ClO2 in the outlet of oxidation column increased first and then decreased while Cl2 barely changed during the experiment. The concentration of Cl2 was far less than ClO2, which indicated that the chlorine-containing gaseous component was mainly in the form of ClO2. After 2 h reaction, the chlorine-containing ions in oxidation liquid before and after reaction were in good consistence with the theoretical calculation. High concentration of Cl- was detected in the absorption liquid, while no ClO2 - and ClO3 - existed. As the reaction proceeded, the oxidation liquid gradually turned into light yellow, and pungent odor released.

Thermal decomposition method is regarded as an important route to treat increasing sewage sludge, while the high content of N causes serious nitrogen related problems, then figuring out the existing form and content of nitrogen of sewage sludge become essential. In this study, XPSpeak 4.1 was used to investigate the functional forms of nitrogen in sewage sludge, peak fitting method was adopted and the best-optimized parameters were determined. According to the result, the N1s spectra curve can be resolved into 5 peaks: pyridine-N (398.7±0.4eV), pyrrole-N(400.5±0.3eV), protein-N(400.4eV), ammonium-N(401.1±0.3eV) and nitrogen oxide-N(403.5±0.5eV). Based on the the experimental data obtained from elemental analysis and spectrophotometry method, the optimum parameters of curve fitting method were decided: background type: Tougaard, FWHM 1.2, 50% Lorentzian-Gaussian. XPS methods can be used as a practical tool to analysis the nitrogen functional groups of sewage sludge, which can reflect the real content of nitrogen of different forms.

The institution of property rights is the core of heritage management systems. The present institution of property rights for heritage in China was born in the middle of the last century, which was the era of planned economy, characterized by vague definition, government monopoly, and an actual absence of regulation. This kind of institution not only leads to heritage damage and inappropriate utilization in practice, but has also become a serious impediment to spontaneous innovation in the institution of property rights in practice. The present institution of property rights in China goes against the sustainable development of cultural and natural heritage.

In modern enterprise management, there exists inevitable conflict among enterprises, society, distributors and consumers. In this case, how to find a good way of communication to achieve the principal objective of customers' satisfaction, enterprises' benefits and the social wealth on the basis of harmonious marketing and to create a friendly relationship among the enterprises, distributors, society and the consumers and eventually to approach the general objective of harmony and win-win situation has gradually and increasingly been concerned by the enterprises, distributors and consumers.