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The ever-increasing challenges related to water security and climate mitigation underscore the pressing need for forward-thinking systems planning tools to drive urban sustainability transitions. In this study, we propose a novel city-level multi-objective planning framework that explores the nexus between carbon trading and water management, with the aim of facilitating water-efficient urban industrial restructuring. The framework integrates cap-and-trade mechanisms into a two-layered optimization model, creating an integrated approach to optimizing carbon emissions and generating economic opportunities for improving water efficiency. To illustrate the potential application of this framework, we conducted a case study focusing on Dongguan City, a water-stressed industrial metropolis in southern China. The results illustrate potential synergies between water planning strategies and carbon trading schemes, which could be harnessed to enable targeted reductions in water usage and carbon emissions. Furthermore, our findings identify the textile, apparel, and paper products manufacturing industries as primary candidates for strategic production scale reduction, emphasizing the importance of sustained support for the development of the computer and electronic manufacturing sector as a catalyst for urban sustainability transitions. By pioneering this new nexus-based perspective, our study offers valuable insights into long-term strategic planning for a low-carbon and resource-efficient urban economy. • Synergizing carbon trading and water management within a novel integrated planning framework. • Implementing resource-efficiency-driven optimization for water- and carbon-intensive manufacturing sectors. • Gaining insights into the specific roles of key manufacturing sectors in water management and carbon trading. • Introducing carbon trading systems may help in promoting water-efficient industrial restructuring. [Display omitted] [ABSTRACT FROM AUTHOR]

Industrial wastewater discharge has become the main cause of water pollution in China. However, the spatial interaction mechanism between industrial structure and water pollution is still unclear. Accordingly, we evaluated and analyzed spatiotemporal changes of the agglomeration pattern of pollution-intensive industrial enterprises and the evolution of the water environmental pollution pattern, as well as the correlation between them. The study results show that the polluting industrial enterprises were located mainly along the Yangtze River and Taihu Lake Basin in southern Jiangsu in 2013 and 2018. However, we observed a spatial trend of pollution transfer to northern Jiangsu. The industrial water pollution discharge presents the distribution pattern of facing rivers, seas, lakes and cities. Papermaking and paper products industry are the leading factors of COD and NH 3 –N pollution, with explanatory power of 0.3666 and 0.6201 respectively. The spatial positive coupling effect between the concentration degree of polluting enterprises and the intensity of water environment pollution discharge is 94.95% of the region. The spatial agglomeration of polluting industrial enterprises is an important cause of water environment pollution. They promote and couple each other, proving the existence of "Pollution haven" and "Porter hypothesis". [Display omitted] • The polluting industrial enterprises are located mainly along the Yangtze River and Taihu Lake Basin. • Papermaking and paper products industry are the leading factors of COD and NH 3 –N pollution. • The spatial agglomeration of polluting industrial enterprises is a significant cause of water environment pollution. • This study proves the existence of "Pollution haven" and "Porter hypothesis". • This study fills the gap in the spatial response mechanisms of different industrial structures and pollutants. [ABSTRACT FROM AUTHOR]

Abstract: Paper production requires fibres to be refined, meaning mechanically treated to present sufficient bonding potential. As it is a highly energy consuming stage, various charges of cellulase as a pre-treatment were investigated to reduce the energy consumption and improve paper properties. The enzyme was added during pulp slushing and conditions of treatment were chosen to be compatible with an industrial application. Results obtained after low consistency disc refining of a softwood bleached kraft pulp were compared at a given drainage index. Enzymatically-treated samples showed a better development of fibrillation leading to a stronger paper. Moreover, fibre swelling was significantly improved. The impact of cellulase charge added to the pulp was identified. However, for all cellulase charges tested, fibre intrinsic resistance was lowered. Consequently fibres became shorter and tear index dropped. A solution was found by applying a milder treatment consisting in reducing refining intensity. This was a way to limit the intense fibre cutting at high refining levels. Moreover, by treating pulp with cellulase, it became possible to reduce refining intensity by 33%, keeping breaking length similar to control. [Copyright &y& Elsevier]

Abstract: The main objective of this work is to evaluate the suitability of rice straw and soda–anthraquinone (soda–AQ) pulping process to produce pulp and paper. To reach this aim, it was used a central composite factorial design to study the influence of operational variables (temperature (155–185°C), cooking time (30–90min), soda concentration (10–20%), anthraquinone concentration (0–1%) and liquid/solid ratio (6–8)), in soda–anthraquinone cooking of rice straw on pulps and paper sheets properties obtained. Based on the yield values obtained, nearly one half of the raw material can be efficiently converted into cellulose pulp and paper sheets. Also, the Kappa number/viscosity ratio of the pulp facilitates its efficient bleaching. Finally, based on the values for above-described physical properties, the pulp can be used to obtain paper or board and recycled paper (as % virgin fibre). In Spain are produced annually 757,000t of rice straw. If we considered an average yield process of 45%, it would be possible to obtain 340,000 tons of pulp. These tons would be absorbed by the market taking into account the necessities in cellulosic pulp consumption. [Copyright &y& Elsevier]

Abstract: The Environmental Effects Monitoring (EEM) Statistical Assessment Tool (SAT) Decision Support System (DSS) has been developed to provide a user-friendly data analysis, display and decision support tool for Canada''s federal environmental effects monitoring program for the pulp and paper and mining industries. The target users include industries, consultants, regional EEM coordinators, National EEM Office and scientists involved in EEM-related research. The tool allows the assessment of the effects of effluent from industrial or other sources on fish and benthic populations. Effect endpoints, which are used as indicators of potentially important effluent effects, are measured at effluent-exposed sites and are compared statistically to measures at reference sites, in order to determine if changes have occurred and the magnitude of the changes. The main driver of the EEM-SAT DSS is its rule-based expert system. The results are used in assessing the adequacy of existing regulations for protecting aquatic environments. [Copyright &y& Elsevier]

Paper sludge is a waste product from the paper and pulp manufacturing industry that is generally disposed of in landfills. Pyrolysis of paper sludge can potentially provide an option for managing this waste by thermal conversion to higher calorific value fuels, bio-gas, bio-oils and charcoal. This work investigates the properties of paper sludge during pyrolysis and energy required to perform thermal conversion. The products of paper sludge pyrolysis were also investigated to determine their properties and potential energy value. The dominant volatile species of paper sludge pyrolysis at 10°C/min were found to be CO and CO2, contributing to almost 25% of the paper sludge dry weight loss at 500°C. The hydrocarbons (CH4, C2H4, C2H6) and hydrogen contributed to only 1% of the total weight loss. The bio-oils collected at 500°C were primarily comprised of organic acids with the major contribution being linoleic acid, 2,4-decadienal acid and oleic acid. The high acidic content indicates that in order to convert the paper sludge bio-oil to bio-diesel or petrochemicals, further upgrading would be necessary. The charcoal produced at 500°C had a calorific value of 13.3MJ/kg. [Copyright &y& Elsevier]

Abstract: In this paper an integrated methodological approach is presented for the evaluation of the implementation of the Best Available Techniques (BAT) in facilities operated under Integrated Prevention Pollution and Control (IPPC) Directive, based on the development and application of a set of sub-indices. An aggregated form of sub-indices that could be used as a composite IPPC facility index is proposed. A sector specific index can be derived from facilities composite indices. This approach uses environmental performance data from European Polluting Emissions Register (EPER) reports, environmental permits and BAT Reference Documents, and gives a coherent and interesting picture of the degree of BAT implementation and an indication of IPPC obligations fulfilment. A specific application is demonstrated concerning the paper manufacturing sector in Greece. It is concluded for this sector that there is a measurable discrepancy from the BAT fulfilment obligations and that the most problematic sub-indices are the “Releases to Water” and “Releases to Air”. [Copyright &y& Elsevier]

The bleaching wastewater effluent from a pulp and paper mill (located in Tianjin, China) was treated with solar photo-Fenton process in a lab-scale reactor (22cm×15cm thermostatic dish). The mill used wastepaper as raw material and the effluent contained 332mgL−1 of total organic carbon (TOC) and 1286mgL−1 of COD. The treatment involved a constant intensity of irradiation (0.2kW/m2) with a solar simulator of 250W xenon lamp and various conditions of pH, temperature, and initial concentrations of H2O2 and Fe(II). The better treatment conditions were searched for in the ranges of initial Fe(II) concentration from 31 to 310mgL−1 (initial pH 3.0, 30°C), initial H2O2 concentration from 0.5 to 3Dth (1Dth=1883mgL−1 for TOC mineralization) (initial pH 3.0, 30°C), initial pH from 2.0 to 6.0 (1 and 2Dth, 10:1 of H2O2/Fe(II), 30°C), and temperature from 30 to 50°C (1Dth, 10:1 of H2O2/Fe(II), initial pH 2.8). TOC removal generally showed the initial fast increase stage within the first sampling time of 15min, followed by the gradual increase stage in the remaining sampling time of 180min experimental time course. The highest percentage of TOC removal in the first stage was about 60% when the initial pH was either 2.8 (H2O2 =1Dth, ratio=10:1, temperature=30–50°C) or 3.5 (H2O2 =2Dth, ratio=10:1, temperature=30°C). Also under the latter condition, the value reached 82% at 120min and was projected to reach 94% at 180min. According to the positive effect of temperature increase on TOC removal observed in this experiment, further increase above these maximum values is possible if the temperature of the above condition were increased from 30 to 40°C or 50°C. Furthermore, under most of the treatment conditions, the TOC removal reached or was projected to reach over 60% toward the end of the experiments. The result indicated that the solar photo-Fenton process has a potential to effectively remove TOC from the wastepaper pulp effluent on a large scale. [Copyright &y& Elsevier]

Turpentine, a mixture of terpenes obtained as a product from oleoresin distillation or as a side product from paper industry, can contribute to the production of oxygenated fuels from renewable sources with properties different from normal alcohols or typical esters. In the present work, the product of turpentine oxyfunctionalization (oxyturpentine), which is composed mainly of nopol, α-terpineol and α-pinene, is evaluated as diesel fuel component blended at 20% vol., by measuring the performance and emissions of a Euro 6 engine under a standard driving cycle. The results show a reduction in particulate number, particulate matter and nitrogen oxides (the tightest emissions from diesel engines), while carbon monoxide and hydrocarbon emissions were increased. The emissions were influenced by the fuel properties and the changes in equivalence ratio and the EGR in the engine (derived from the fuel properties). These results show a high potential of oxyturpentine to be used as component of diesel fuel. • The oxyturpentine content affects both the EGR and the equivalence ratio in the engine. • NOx was decreased when diesel engine was fueled with diesel + oxyturpentine blend. • Oxygen content of oxyturpentine reduces particle mass and particle number emissions. • At cold-engine conditions, hydrocarbon and carbon monoxide emissions increased sharply. [ABSTRACT FROM AUTHOR]

The mechanism of the environmental regulations affecting carbon emissions is complex, and for many years it has been a hot research topic for researchers. However, few of the previous studies have focused on whether or not environmental regulations can potentially influence carbon emissions through technical efficiency. Therefore, the present study chose to investigate the mediation effects of the technical efficiencies between environmental regulations and carbon emissions using the provincial panel data of energy-intensive industries for the period ranging from 2005 to 2015. The results were as follows: (i) In regard to the entire group of energy-intensive industries, it was found that environmental regulations could not only potentially directly reduce carbon emissions, but also indirectly reduce carbon emissions through technical efficiency. In other words, technical efficiency had played a partial mediation role between the environmental regulations and the carbon emissions; (ii) It was observed that for the different subdivided energy-intensive industries, the different levels of technical efficiency had shown various mediation effects. For example, the mediation effects of technical efficiency in the petroleum processing and coking (PPC) industry; papermaking and paper products (PPP) industry, and raw chemical materials and chemical products (RCMCP) industry, were found to be similar to those of the whole energy-intensive industries. Furthermore, the "Porter Hypothesis" had been verified in the nonmetal mineral products (NMP) industry. However, there were no mediation effects observed in the smelting and pressing of ferrous metals (SPFM) and smelting and pressing of nonferrous metals (SPNM) industries; (iii) In this study, in accordance with the regression results of the double-threshold models, it was found that for the energy-intensive industries as a whole, the carbon emission reduction effects of environmental regulations had become stronger with the increases in technical efficiency. For the PPP and RCMCP industries, there was an inverted U-shaped relationship observed between environmental regulations and carbon emissions when the technical efficiency was taken as the threshold variable. Therefore, based on the research conclusions achieved in this study, some policy recommendations were put forward. • Environmental regulation reduces carbon emission of the energy intensive industries of China. • Technical efficiency plays a partial mediation effect between environmental regulation and carbon emission. • The mediation effects of technical efficiency differ in the subdivided energy-intensive industries. • The "Porter hypothesis" is verified in Nonmetal Mineral Products (NMP) industry. [ABSTRACT FROM AUTHOR]