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The Strategies of Reviving the Old Industrial Bases provide opportunities for low-carbon transition in Northeast China, which is one of the earliest regions to industrialize and the largest rustbelt in China, but study on the impacts of its socioeconomic factors on CO 2 emissions is still in short, though it is essential for guiding the pathways to achieve low-carbon socioeconomic transition. We adopted the structural decomposition analysis (SDA) to identify the main contributors to emissions increase in Heilongjiang province during 2002–2012, which is the heartland of Northeast revitalization. The results show that the increase in CO 2 emissions was mainly driven by growth in per-capita final demand, which generated 203.8 Mt (153.6%) upstream CO 2 emissions between 2002 and 2012. Changes in production structure and final demand structure had smaller impacts on CO 2 emissions increase (36.1 Mt and 27.0 Mt). However, the positive influences were largely overwhelmed by change in emission intensity, which avoided 135.4 Mt (−102%) CO 2 emissions. Therefore, appropriate measures related to energy structure optimization and efficiency improvement should be implemented. Especially, increasing the proportion of wind, solar and biomass energy in Heilongjiang, where renewable energy is abundant, would reduce the CO 2 emissions significantly. In addition, domestic export took the lead position in driving the CO 2 emissions in Heilongjiang, accounting for 37.6%–43.1% annual emissions between 2002 and 2012. Thus, some financial instrument, such as tax relief for less carbon intensive exports could be adopted to prompt upstream suppliers to decarbonize their production processes. Unlabelled Image • Structural decomposition analysis (SDA) is used to identify the main contributors of CO 2 emissions increase during 2002-2012 in Heilongjiang province. • Growth in per-capita final demand was main driver for CO 2 emissions Increase. • The positive influences were largely overwhelmed by change in emission intensity, which avoided 135.4 Mt (-102%) CO 2 emissions. • Domestic export took the lead position in driving the CO2 emissions in Heilongjiang, accounting for 37.6%-43.1% annual emissions between 2002-2012. [ABSTRACT FROM AUTHOR]

Commodity trade between regions implies a large amount of energy transfer. As an important economic growth pole of China, the Jing-Jin-Ji area (Beijing-Tianjin-Hebei) is also one of the areas with the largest energy consumption in China. Moreover, the primary energy consumer goods in this area are fossil fuels, such as coal. This has led to serious air pollution in the area. Therefore, the reduction of energy consumption under the premise of maintaining sustained economic growth is an important task of the Jing-Jin-Ji area. In this study, an interprovincial input-output model was applied to quantitatively estimate the embodied energy transfer between Jing-Jin-Ji area and other provinces in China. The results indicated that the Metal and nonmetal mineral processing industry and the Electrical, gas and water industry in the Jing-Jin-Ji area exported a large amount of embodied energy to the Yangtze River Delta and the Pearl River Delta. However, the embodied energy export of the Jing-Jin-Ji area mainly exported by Hebei province. Beijing and Tianjin even have some net import of embodied energy. The embodied energy transfer between Tianjin, Hebei and other provinces was mainly driven by investment, while the main media of embodied energy transfer between Beijing and other provinces was consumption. Therefore, we suggest that the Jing-Jin-Ji area should further increase the degree of dependence on other provinces' energy-intensive products and reduce the export of energy-intensive products. In addition, there should be difference in the energy and industrial policies among Beijing, Tianjin and Hebei, and the problems of high energy consumption and high proportion of heavy industry in Hebei should be first resolved. [ABSTRACT FROM AUTHOR]

The development and application of Fenton and ozonation systems in landfill leachate treatment over the last 20 years, and the current research status are reviewed in this paper, with an emphasis on the technical and economic characteristics of Fenton and ozonation systems used to treat different types of landfill leachate. To date, a total of 101 and 78 articles have been published regarding leachate treatment by Fenton and ozonation systems, respectively. These articles considered the use of two systems to treat aged leachate, biologically treated leachate and leachate comprising the concentrated solution resulting from reverse osmosis (RO). The oxidization mechanisms of the two systems used to treat landfill leachate significantly differed in terms of their optimal process parameters (e.g., initial pH value, reagent dosage, and reaction time) and removal efficiency. The Fenton and ozonation systems outperformed persulfate-based advanced oxidation technology in terms of their improved biodegradability of landfill leachate and engineering practicability. The cost of the reagents required to treat landfill leachate by Fenton and ozonation systems accounted for at least 85% of the total operating cost. In contrast to the ozonation system, the Fenton system was more cost-effective when both systems were used to treat the same type of landfill leachate. This study provides a theoretical basis for the operation of Fenton and ozonation systems and also offers technical support for landfill leachate disposal companies that opt to use these technologies. Unlabelled Image • Studies of landfill leachate disposal by Fenton and ozonation systems were reviewed. • Water quality characteristics were determined for different leachate. • Mechanism, parameters, and efficiency in Fenton and ozonation systems were discussed. • Operating costs of Fenton and ozonation systems were established. [ABSTRACT FROM AUTHOR]

Landfill leachate contains high concentrations of complex organic matter (OM) that can severely impact the ecological environment. If landfill leachate is to be treated using a combined "biological + advanced treatment" process, the molecular information of OM must be investigated to optimize the operation parameters of the combined process and maximize the removal of organic pollutants. This study applied ultra-high resolution mass spectroscopy to investigate the degradation and transformation characteristics of refractory OM in mature landfill leachate at the molecular level (m / z = 150–800) during biological treatment (i.e., semi-aerobic aged refuse biofilter, SAARB) and subsequent chemical oxidation (i.e., the Fenton process and ozonation). After SAARB treatment, the polycyclic aromatics (aromatic index, AI > 0.66) and polyphenol (0.66 ≥ AI > 0.50) contents increased, and the highly unsaturated phenolic compounds (AI ≤ 0.50 and H/C < 1.5), which have a high bioavailability, were mostly removed. Compared with raw leachate, SAARB effluent (i.e., SAARB leachate) contained fewer organics with short carbon chains, more organics with long carbon chains, an elevated condensation degree for organics and, thus, a considerably reduced biodegradability. Although both the Fenton and ozonation processes could remove many of the polycyclic aromatics and polyphenols, ozone produced considerable amounts of aliphatic compounds with high bioavailability. Compared to ozonation, the Fenton process utilized the hydroxyl radical to non-selectively react with OM and produced better mineralization results. Unlabelled Image • The Fenton process had a better mineralization effect for leachate treatment. • The SAARB process cannot remove polycyclic aromatic and polyphenol compounds. • Transformation of DOM in Chemical treatment was characterized by ESI FT-ICR MS. • The types of OM targeted by ozonation and the Fenton process are quite different. [ABSTRACT FROM AUTHOR]

Biochar is a carbon-rich material that can be obtained from pyrolysis of solid waste (e.g., agricultural solid waste and sludge from wastewater treatment plants). Biochar features low cost, large specific surface area, and strong adsorption capacity. New biochar composites can be produced via modification and loading of nano particles onto biochar. Biochar can contribute to the dispersion and stabilization of nano particles. In addition, nano particles can increase the number of surface-active sites, which improves the physicochemical properties of the material. Biochar and biochar composites have been applied widely in wastewater treatment, and have significantly enhanced the treatment performance of Fenton-like processes (activation of hydrogen peroxide and persulfate) as an advanced oxidation process for organics removal and wastewater decontamination. This paper reviews the preparation methods for biochar and biochar composites to systematically analyze the influential factors on the preparation process. The paper also comprehensively reviews the mechanisms by which biochar removes different organic pollutants. However, due to the vast number of different biochar feedstocks and their preparation methods, it is difficult to compare the properties of one biochar to another. Guidance if provided for the application of biochar and biochar composites for wastewater decontamination. Unlabelled Image • Performance of biochar is determined by preparation factors and loading processes. • The mechanism by which biochar adsorbs pollutants in water was analyzed. • Activation mechanisms for H 2 O 2 , PS, and PMS by biochar were determined. • Biochar shows great promise for the removal of pollutants from water. [ABSTRACT FROM AUTHOR]

Municipal solid waste (MSW) incineration is widely used in China. Concentrated leachate, containing high concentrations of pollutants, is an important type of secondary pollution produced in MSW incineration power plants and requires proper treatment. In this study, various coagulants were used to treat concentrated leachate from a nanofiltration (NF) membrane that treated leachate from an MSW incineration plant. The optimal coagulation condition was determined in this study. Under the optimal condition, removals of chemical oxygen demand, light absorbing substances (at 254 nm), total nitrogen, color and turbidity were 68.42%, 69.01%, 44.14%, 92.31% and 87.44%, respectively. Much of the refractory organic matter with relatively high molecular weight, aromaticity and humification degree was removed, and effluent had a lower molecular weight than raw NF concentrated leachate. Study also found that some parts of high molecular weight compounds from NF CL were removed by coagulation process, but the change of distribution of molecular weight was not outstanding. The NF concentrated leachate, both before and after coagulation, contained a large amount of chloride. Hence, a follow-up study should be conducted to find an effective additional processing that can remove organic matter using the high concentration of chloride in the NF concentrated leachate coagulation effluent. This study provides a theoretical basis for the treatment of concentrated leachate from MSW incineration power plants. Unlabelled Image • Comparison of four coagulants for treatment of nanofiltration concentrated leachate • Effect of dosage of coagulants, coagulation aids and pH on coagulation process • >68% of COD Cr and>90% of color were removed by optimal coagulation condition. • Characteristics of DOM in samples were investigated using multiple ways. [ABSTRACT FROM AUTHOR]