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An adequate understanding about the evolutionary process, mechanism and influencing factors of cultural landscapes is crucial for their efficient preservation and sustainable development. The theoretical framework of self-reinforcing sequence in path dependence analysis appears applicable but has not yet been well explored as a tool for broader historical landscape analysis like the evolution of cultural landscapes that may last thousands of years. Within such a framework, an empirical case of Buddhist heritage landscape of Mount Wutai is used to account for the institutional genesis, reproduction and change associated with landscape evolution over time. The findings suggest the framework provides an essential toolkit to reveal the specific ways in which path dependence shapes the evolutionary trajectories of cultural landscapes and, based on that, to detect management options that steer development and change of cultural landscapes into a direction that aligns with desired outcomes. [ABSTRACT FROM AUTHOR]

In the process of exploitation, transportation and refining of high-sulfur crude oil, a large number of oil sludge (OS) with high sulfur content is produced. Pyrolysis has been proved to be an effective method for OS disposal, but for solid waste with high sulfur content, lots of sulfur-containing gases will be released during thermal disposal. The addition of calcium oxide in pyrolysis process is an economical and effective way to capture sulfur-containing gases. In order to understand the pyrolysis process of OS with CaO, a thermogravimetric analyser was used to conduct pyrolysis experiments of OS with different Ca/S molar ratios (0, 1, 2 and 3) at different heating rates (10°C/min, 20°C/min, 30°C/min and 40°C/min). The results showed that with the increase of CaO addition the derivative thermogravimetric curves showed a gentle trend. In addition, new weight loss peaks were occurred at 700–900°C and after 1100°C, which were the decomposition of calcium carbonate and calcium sulfate, respectively. The kinetic parameters were solved by Friedman, FWO, and Starink methods, and the results were similar, with an average activation energies (E) value of 214 kJ/mol. The change trend of the activation energy was followed by an increase and then a decrease corresponding to the change of energy demand for the reaction. The calculated average values of ΔH, ΔG and ΔS were about 207, 447 and −0.3250 kJ/mol, respectively. When the conversion rate was 0.5, the thermodynamic parameters reached their maximum values. [ABSTRACT FROM AUTHOR]

This article proposed an original comprehensive thermal treatment coupled with gasification and combustion (CGC) of oil sludge (OS), which was designed to produce hydrogen-rich syngas. Based on the experimental results of OS gasification with steam, the combustion characteristics of char from OS gasification were analyzed by thermogravimetric experiments under different heating rates of 10, 20 and 30 °C/min. The combustion process of OS gasification char can be divided into three stages, including water evaporation, volatile combustion and heavy component combustion. The average values of activation energy (E) obtained by Friedman, FWO and Starink methods were 89.98 kJ/mol, 147.61 kJ/mol and 143.09 kJ/mol, respectively. According to OS gasification and OS gasification char combustion experiments, the comprehensive thermal treatment process CGC of OS was simulated by Aspen Plus. The simulation results showed that increasing both gasification temperature and the mass ratio of steam to OS (SOS) could promote the hydrogen production. Considering energy consumption, the recommended OS gasification temperature, SOS and char combustion temperature were 800 ∼ 900 °C, 0.3 ∼ 0.5, and 900 ∼ 1000 °C, respectively, which could ensure full burning of char and reduce the generation of pollutants. The CGC process could reduce CO2 emissions by 44.2% from carbon flow analysis. [ABSTRACT FROM AUTHOR]

The efficient recovery and conversion of energy in oily sludge has great prospects. In this article, the main objective is to investigate the impact of the addition of CO2 during the pyrolysis of oily sludge on energy recovery and conversion by thermogravimetric analysis (TGA) and compare the effect with the traditional pyrolysis effect from the perspective of thermal conversion behavior, products composition, and kinetics analysis. The results of the experiment showed that in the CO2 atmosphere, the main weight loss temperature of oily sludge was mainly concentrated in the range of 300–500 °C, which is lower than the reaction temperature range of traditional pyrolysis. The yields of CO and H2 in the products have been greatly improved, and the highest proportion in the gas products can reach 19.29% and 22.38%, respectively. The Ea (activation energy) values of oily sludge were determined to be in the range of 40–120 kJ·mol−1 with the conversion between 0.2 and 0.8 via DAEM, KAS, Starink, and FWO methods, respectively, in which the FWO method has shown the strongest adaptability. The results of this study provide reference values for practical engineering applications. [ABSTRACT FROM AUTHOR]

Oil sludge is a typical hazardous waste in the petrochemical and electric power industry. It has complex components and special properties, and has serious hazards to humans, plants, water, and soil. Therefore, how to realize the effective disposal of oil sludge has become an urgent issue to be solved worldwide. Among the existing oil sludge treatment approaches, combustion has been considered to be a promising technology to realize the large-scale industrial application. In the present work, the characteristics of oil sludge were described in detail. The application and development of oil sludge combustion technology were critically summarized and discussed, including factors affecting combustion, drying process, combustion characteristics, synergistic treatment technology, and formation and control of secondary pollution. Besides, the development of combustion equipment, and integrated thermal treatment technology for oil sludge were prospected. This work can be used for guiding the industrial disposal of oil sludge. [ABSTRACT FROM AUTHOR]

Pyrolysis can realise the harmlessness, reduction and resource utilisation of petroleum sludge in a short period. In the present work, a tank bottom sludge (SSOS) and a landing sludge (SLOS) from Shengli Oilfield were used for experimental research. Thermogravimetric testing is used to initially determine the optimal range of pyrolysis temperature. Pyrolysis experiments were performed in a tube furnace reactor. Pyrolysis products were collected and analysed separately. The char yield of SSOS and SLOS were 50% and 70%, respectively. Although there are differences in the oil content of the two types of petroleum sludge, the oil yield remained nearly the same, which were both between 7% and 8%. As the pyrolysis temperature was raised to 500°C, the yield of each product did not change greatly while their composition had obvious changes. High temperature is more conducive to the production of small molecule products. Result showed that pyrolysis treatment of petroleum sludge can effectively recover energy materials in the form of pyrolysis gas and oil. The heating value of char is lower than that of petroleum sludge, which means that char is not suitable for direct use as fuel. Pyrolysis treatment also showed good curing effect on Cr, which reached 85%. However, the solidification effect decreased as pyrolysis temperature increasing. It is necessary to pay attention to the heavy metal contained in char as soil improver. The rich surface structure of char provides evidence to produce high value-added carbon materials. [ABSTRACT FROM AUTHOR]

Combustion of High-sulfur oil sludge (OS) blended with CaO can significantly reduce the emission of sulfur gas pollutants, but its combustion and kinetic characteristics need to be further studied. TGA experiments showed the combustion characteristics of OS were significantly changed after adding CaO. As reflected by comprehensive combustion index (S), the combustion performance of OS decreased after adding CaO, and significantly improved with the increase of heating rate. The kinetic parameters of the main combustion process of OS with CaO were calculated by the iso-conversion methods of Friedman, FWO, and Starink, respectively. Kinetic analysis results indicated the energy required for OS combustion with CaO first increased and then decreased with deepening of reaction degree. The thermodynamic parameters of ΔH, ΔG and ΔS were determined on the basis of kinetics. The negative ΔH, positive ΔG, and negative ΔS validated the combustion of OS with CaO was an exothermic and nonspontaneous process. [ABSTRACT FROM AUTHOR]

In order to explore the effect of CaO on the ecological risk of chromium (Cr), copper (Cu) and zinc (Zn) in Oily sludge (OS), the incineration experiments of OS with and without calcium oxide (CaO) additive were carried out respectively in a horizontal tube furnace at the temperature ranging from 800 °C to 1000 °C. Furthermore, the ecological risk based on Risk Assessment Code (RAC) of Cr, Cu and Zn in OS, bottom ash from OS incineration (OSA) and bottom ash from OS incineration in the presence of CaO additive (OSA-CaO) were investigated in this work. The results showed that most of the Cr and Cu in OS remained in bottom ash, while Zn volatilized with the flue gas. At the same time, the RAC of Cr, Cu and Zn in OS decreased significantly after incineration. Compared with OSA, CaO obviously promoted the stabilization of Cr and Cu in OSA-CaO, but had little effect on the behavior of Zn. Moreover, CaO also reduced the RAC of Cu and Zn in samples, and reduced its harm to ecosystem. This study supplied essential data and theoretical support for the industrial treatment of OS, and was of great help to the harmless treatment of OS. [ABSTRACT FROM AUTHOR]

Experimental and simulation studies on the migration characteristics of heavy metals during the incineration of OS were conducted with a tube furnace reactor and thermodynamic equilibrium calculation software FactSage, respectively. The results showed that when the incineration temperature increased from 800°C to 1100°C, the release rates of heavy metals such as Cr, Pb, Cu, Zn and Ni increased gradually and reached the maximum at 1000°C. When the excess air ratio increased from 1.0 to 1.4, the release rates of heavy metals such as Cr, Pb, Cu, Zn and Ni first decreased and then became steady. The content of gaseous hydroxide of Cr and gaseous chlorides of Pb and Cu increased while the chemical forms of Zn and Ni did not change obviously with the increase of combustion temperature or excess air ratio. [ABSTRACT FROM PUBLISHER]