Jingzheng Ren

Emergy analysis and sustainability efficiency analysis of different crop-based biodiesel in life cycle perspective.

Biodiesel as a promising alternative energy resource has been a hot spot in chemical engineering nowadays, but there is also an argument about the sustainability of biodiesel. In order to analyze the sustainability of biodiesel production systems and select the most sustainable scenario, various kinds of crop-based biodiesel including soybean-, rapeseed-, sunflower-, jatropha- and palm-based biodiesel production options are studied by emergy analysis; soybean-based scenario is recognized as the most sustainable scenario that should be chosen for further study in China. DEA method is used to evaluate the sustainability efficiencies of these options, and the biodiesel production systems based on soybean, sunflower, and palm are considered as DEA efficient, whereas rapeseed-based and jatropha-based scenarios are needed to be improved, and the improved methods have also been specified.

Prioritization of bioethanol production pathways in China based on life cycle sustainability assessment and multicriteria decision-making

PurposeThe study objectives are twofold: (i) combining the life cycle sustainability assessment (LCSA) framework and the multicriteria decision-making (MCDM) methodology for sustainability assessment and (ii) determining the most sustainable scenario for bioethanol production in China according to the preferences of the decision-makers/stakeholders.MethodsLife cycle assessment (LCA), life cycle costing (LCC), and social life cycle assessment (SLCA) are combined to collect the corresponding criteria data on environmental, economic, and social aspects, respectively. The study develops a novel SLCA method for quantifying the social criteria. The decision-makers/stakeholders can use linguistic terms to assess these criteria, and fuzzy theory is used to transform the linguistic variables into real numbers. Once the sustainability assessment criteria are determined, the study develops an MCDM method that combines the analytic hierarchy process (AHP) and the VIKOR method to prioritize the alternatives. The AHP is used to determine the criteria weights that are a prerequisite when using VIKOR; the VIKOR method is then used to determine the sustainability sequence of the scenarios.Results and discussionThe study’s proposed method investigates an illustrative case about three alternative bioethanol production scenarios (wheat-based, corn-based, and cassava-based): The prior sequence (based on the sustainability performances) in descending order is cassava-based, corn-based, and wheat-based. The proposed methodology results allow Chinese decision-makers/stakeholders to select the most sustainable scenario among many alternatives. The proposed methodology is generic, meaning that further alternatives can be studied and the most sustainable option can be ultimately determined.ConclusionsThe main study contribution is to test the combination of an MCDM methodology and LCSA for sustainability decision-making by studying three alternative pathways for bioethanol production in China. The proposed method feasibly enables the decision-makers/stakeholders to find the most sustainable scenario to achieve their objectives among various alternatives.

Life cycle cost optimization of biofuel supply chains under uncertainties based on interval linear programming.

The aim of this work was to develop a model for optimizing the life cycle cost of biofuel supply chain under uncertainties. Multiple agriculture zones, multiple transportation modes for the transport of grain and biofuel, multiple biofuel plants, and multiple market centers were considered in this model, and the price of the resources, the yield of grain and the market demands were regarded as interval numbers instead of constants. An interval linear programming was developed, and a method for solving interval linear programming was presented. An illustrative case was studied by the proposed model, and the results showed that the proposed model is feasible for designing biofuel supply chain under uncertainties.

How can a life cycle inventory parametric model streamline life cycle assessment in the wooden pallet sector

PurposeThis study discusses the use of parameterization within the life cycle inventory (LCI) in the wooden pallet sector, in order to test the effectiveness of LCI parametric models to calculate the environmental impacts of similar products. Starting from a single case study, the objectives of this paper are (1) to develop a LCI parametric model adaptable to a range of wooden pallets, (2) to test this model with a reference product (non-reversible pallet with four-way blocks) and (3) to determine numerical correlations between the environmental impacts and the most significant LCI parameters; these correlations can be used to improve the design of new wooden pallets.MethodsThe conceptual scheme for defining the model is based on ISO14040-44 standards. First of all, the product system was defined identifying the life cycle of a generic wood pallet, as well as its life cycle stages. A list of independent and dependent parameters was used to describe the LCI flows of a generic wooden pallet. The LCI parametric model was applied to calculate the environmental impacts of the reference product, with regard to a selection of impact categories at midpoint level (climate change, human toxicity, particulate matter formation, agricultural land occupation, fossil depletion). The model was then applied to further 11 wooden pallets belonging to the same category.Results and discussionThe definition of a LCI parametric model based on 31 independent parameters and 21 dependent parameters streamlined the data collection process, as the information required for fulfilling the LCI are standard information about the features of the wooden pallet and its manufacturing process. The contribution analysis on the reference product revealed that the most contributing life cycle stages are wood and nails extraction and manufacturing (positive value of environmental impact) and end-of-life (avoided impact). This result is driven by two parameters: mass of wood and average distance for transport of wood. Based on the results of the application of the LCI parametric model to the identified products, one parameter-based regression and one multiple non-linear regression allowed to define a correlation between the life cycle impact assessment (LCIA) category indicators considered and the most influencing parameters.ConclusionsThe definition of LCI parametric model in the wooden pallet sector can effectively be used for calculating the environmental impacts of products with different designs, as well as for obtaining a preliminary estimation of the life cycle environmental impacts of new products.

Design for sustainability of industrial symbiosis based on emergy and multi-objective particle swarm optimization

Industrial symbiosis provides novel and practical pathway to the design for the sustainability. Decision support tool for its verification is necessary for practitioners and policy makers, while to date, quantitative research is limited. The objective of this work is to present an innovative approach for supporting decision-making in the design for the sustainability with the implementation of industrial symbiosis in chemical complex. Through incorporating the emergy theory, the model is formulated as a multi-objective approach that can optimize both the economic benefit and sustainable performance of the integrated industrial system. A set of emergy based evaluation index are designed. Multi-objective Particle Swarm Algorithm is proposed to solve the model, and the decision-makers are allowed to choose the suitable solutions form the Pareto solutions. An illustrative case has been studied by the proposed method, a few of compromises between high profitability and high sustainability can be obtained for the decision-makers/stakeholders to make decision.

Multi-actor multi-criteria sustainability assessment framework for energy and industrial systems in life cycle perspective under uncertainties. Part 2: improved extension theory

PurposeThe concept of sustainability and sustainable development has been widely incorporated in energy and industrial systems. This paper is the second part of a two-paper series dealing with multi-actor multi-criteria sustainability assessment of alternative energy and industrial systems in life cycle perspective under uncertainties.MethodsThe criteria system including four macroscopic aspects (environmental, safety, social and economic aspects) has been developed for sustainability assessment of energy and industrial systems. An improved extension theory which can address interval decision-making matrix has been developed for determining the sustainability degree of the energy and industrial systems.Results and discussionThe weights of the criteria for sustainability assessment are the first part of the two-paper series. An illustrative case has been studied by the proposed multi-criteria decision-making method, and the sustainability of six alternative options for the production of a 1-t product was investigated. The sustainability degree of these six alternative options can be determined by the proposed method.Conclusions and perspectivesA methodology for multi-actor multi-criteria sustainability assessment of energy and industrial options has been developed in this study, the traditional extension theory has been modified to deal with the uncertainty problems and the proposed method can rank the alternative energy and industrial systems with the decision-making matrix in which the data of the alternatives with respect to the evaluation criteria are intervals. In the improved extension theory, sustainability has been dived into five grades: excellent, good, satisfied, barely adequate and fail. According to the method for calculating the weights of the criteria for sustainability assessment proposed in part 1, these weights were used to calculate the integrated dependent degree which is a measure of what degree an alternative belongs to the classical fields. An optimal programming model for maximizing the satisfied degree has been developed to rank the sustainability sequence of the alternative options and determine the sustainability degree of each alternative.

GM(1,N) method for the prediction of anaerobic digestion system and sensitivity analysis of influential factors

Anaerobic digestion process has been recognized as a promising way for waste treatment and energy recovery in a sustainable way. Modelling of anaerobic digestion system is significantly important for effectively and accurately controlling, adjusting, and predicting the system for higher methane yield. The GM(1,N) approach which does not need the mechanism or a large number of samples was employed to model the anaerobic digestion system to predict methane yield. In order to illustrate the proposed model, an illustrative case about anaerobic digestion of municipal solid waste for methane yield was studied, and the results demonstrate that GM(1,N) model can effectively simulate anaerobic digestion system at the cases of poor information with less computational expense.

The Role of Science Diplomacy: A Historical Development and International Legal Framework of Arctic Research Stations under Conditions of Climate Change Post-Cold War Geopolitics and Globalization/Power Transition

The Arctic is undergoing transformation, where three important drivers are climate change, post-Cold War geopolitics and globalization/power transition from the rise of China. This transformation defines the nexus between science diplomacy, geopolitics, law and globalization under climate change, which is shaping the future of the Arctic and will bring considerable opportunity at national, regional and global levels. Research infrastructures (research stations both military and non-military, observation and monitoring networks) are opening access and data to new Arctic and non-Arctic players. Additional logistics hubs than those already existing are and should be established. Countries are sustaining and building new research as well as search and rescue bases/stations. Stations can be used as indicator of this transformation as well as their implications to improve cooperation, engage in multilateral rather than unilateral actions to protect the Arctic infrastructures and to improve military capabilities. These actions have started to attract also non-Arctic actors, such as China and the European Union (EU), which are developing new policies. Stations may not be developed and maintained only not only for the purpose of the scientific understanding of climatic and environmental impacts but also for function as entities that legitimize national or sovereign claims. At the nexus are the scientists that utilize the research bases and their international colleagues. Arctic/Northern bases are primarily military for historical reasons and for reasons of logistics and expertise, as historically indicated through the American presence in Alaska. This is not the same as saying that the bases are militarized—or part of some national militarization strategy in the Arctic. New steps to identify the role of stations at national, regional and global levels are needed. In this essay, we explore the implications and opportunities for these stations to act as pivots between scientific and geopolitical issues. We argue that where there is scientific collaboration, there is less risk of military conflict and that the Arctic is not “militarized” based on the international politics and science diplomacy of the Arctic.

Multi-actor multi-criteria sustainability assessment framework for energy and industrial systems in life cycle perspective under uncertainties. Part 1: weighting method

PurposeLife cycle sustainability assessment is meaningful for the decision-makers/stakeholders to select the most sustainable option among multiple alternatives; however, there are usually various severe uncertainty problems in sustainability-oriented decision-making, i.e., the vagueness and ambiguity that existed in human judgments and the lack of information. This study aims at developing a novel life cycle multi-criteria sustainability assessment method for helping the decision-makers/stakeholders to determine the sustainability level of the industrial and energy systems. In part 1, an improved interval analytic hierarchy process (AHP) which allows multiple decision-makers/stakeholders to participate in the decision-making was developed to determine the weights of the criteria which were used in life cycle sustainability assessment.MethodsIt is usually difficult for the decision-makers/stakeholders to use the numbers from 1 to 9 and their reciprocals for determining the comparison matrix when using the traditional AHP method for weight calculation, because human judgments usually involve various uncertainties. In order to the overcome this weak point of the traditional AHP, an improved AHP, so-called interval AHP, in which, multiple decision-makers/stakeholders are allowed to participate in the decision-making and allowed to use interval numbers instead of crisp numbers to establish the comparison matrix for determining the weights of the criteria for life cycle sustainability assessment, has been developed.Results and discussionThe proposed method was used to determine the weights of the four aspects for life cycle sustainability assessment including economic, safety, social, and environmental aspects. Five representative stakeholders were invited to participate in the decision-making. After Monte Carlo simulation, the final weights of the four aspects have been determined with the proposed interval AHP.Conclusions and perspectivesAn interval AHP method was developed for determining the weights of the criteria for life cycle sustainability assessment; the decision-makers are allowed to use interval numbers to establish the comparison matrix for weight calculation. The weighting coefficients determined by Monte Carlo method can accurately reflect the preferences and willingness of multi-actor comparing with the traditional AHP method. This paper merely presents a novel method to calculate the weights of the criteria for life cycle sustainability assessment, but the method for determining the sustainability performance has been presented in part 2.

Competitiveness prioritisation of container ports in Asia under the background of China’s Belt and Road initiative

ABSTRACT The understanding of the competitiveness of different ports under the background of China’s “Belt and Road Initiative” (BRI) is critical for drafting appropriate plans and taking suitable actions to select the best port in the logistics supply chains. A novel Multi-Attribute Decision Analysis (MADA) was proposed for the evaluation of port competitiveness. In the developed MADA method, the interval Analytic Hierarchy Process and the projection method was combined for the evaluation of port competitiveness. Three container ports in Asia including Shanghai, Hong Kong, and Singapore were studied under the background of China’s BRI. The results demonstrate that the port of Singapore is the most competitive at the initial stage of China’s BRI, followed by Hong Kong and Shanghai in the descending order. The results were validated by sum weighted method and Technique for Order Preference by Similarity to an Ideal Solution method, and sensitivity analysis was also carried out. The competitiveness of the three ports in the next ten years were also studied with the consideration of the influences of China’s BRI, and the results reveal that Shanghai port can even exceed Hong Kong port and Singapore port if it can effectively take the advantage s of China’s BRI.