Introduction:China’s import bans on solid wastes starting from 2017 have challenged the global trade system of plastic wastes,which remains poorly characterized.This study chooses polyethylene(PE)as a case and aims t...Introduction:China’s import bans on solid wastes starting from 2017 have challenged the global trade system of plastic wastes,which remains poorly characterized.This study chooses polyethylene(PE)as a case and aims to map out the global trade networks of PE waste(GPETN)from 1976 to 2017.Outcomes:We find that the size and complexity of the GPETN had been growing until 2016.After the mid-1990s,PE waste basically flowed from developed economies,mainly the EU and the US,to developing economies such as China.Since 2001 when admitted into the WTO,China’s PE waste import surged until 2014 when it absorbed over 60%of global export.Regulations on solid waste import following the Green Fence campaign in 2013 resulted in substantial reductions in China’s import as well as the global export of PE waste after 2014.Several other developing economies,such as Malaysia,Turkey,and Vietnam,had transitioned to net importers,but their imports were insufficient to replace China as new recycling bases for PE waste.Conclusion:The results highlight the urgent need of a joint effort for developed and developing countries to build a stronger global circular economy system with sufficient capacity to treat PE waste locally.展开更多
A green economy is an economy that aims to reduce environmental risks and ecological scarcities,and that lines up sustainable development without degrading the environment.Waste can be solid,liquid,or gas and each typ...A green economy is an economy that aims to reduce environmental risks and ecological scarcities,and that lines up sustainable development without degrading the environment.Waste can be solid,liquid,or gas and each type has different methods of disposal and management.Since the common principles of management are efficiency and fairness,Blockchain as a peer-to-peer concept with a consensus mechanism is suitable for waste management.The paper presents the first stage of project“Blockchain in solid waste management”.From several points of view a review of solid waste management is performed,in which the blockchain has the major role:(1)problem definition and possible solutions;(2)Blockchain applications in solid waste management;(3)blockchain applications for different solid waste types;(4)blockchain elements for waste management;(5)blockchain in cooperation with other technologies.The author syntheses advanced sorting process,models of Blockchain in solid waste trading,and three use cases with selected granularity.The used design methodology is unified modelling language:activity diagrams and communication diagrams.The author applies the principles of supply and demand.The models are intended for business developers,university professors,and students.展开更多
基金This Study is supported by the National Natural Science Foundation of China[41671523,7191101150]Leading Project of Fujian Science and Technology Department[2017Y0080].
文摘Introduction:China’s import bans on solid wastes starting from 2017 have challenged the global trade system of plastic wastes,which remains poorly characterized.This study chooses polyethylene(PE)as a case and aims to map out the global trade networks of PE waste(GPETN)from 1976 to 2017.Outcomes:We find that the size and complexity of the GPETN had been growing until 2016.After the mid-1990s,PE waste basically flowed from developed economies,mainly the EU and the US,to developing economies such as China.Since 2001 when admitted into the WTO,China’s PE waste import surged until 2014 when it absorbed over 60%of global export.Regulations on solid waste import following the Green Fence campaign in 2013 resulted in substantial reductions in China’s import as well as the global export of PE waste after 2014.Several other developing economies,such as Malaysia,Turkey,and Vietnam,had transitioned to net importers,but their imports were insufficient to replace China as new recycling bases for PE waste.Conclusion:The results highlight the urgent need of a joint effort for developed and developing countries to build a stronger global circular economy system with sufficient capacity to treat PE waste locally.
文摘A green economy is an economy that aims to reduce environmental risks and ecological scarcities,and that lines up sustainable development without degrading the environment.Waste can be solid,liquid,or gas and each type has different methods of disposal and management.Since the common principles of management are efficiency and fairness,Blockchain as a peer-to-peer concept with a consensus mechanism is suitable for waste management.The paper presents the first stage of project“Blockchain in solid waste management”.From several points of view a review of solid waste management is performed,in which the blockchain has the major role:(1)problem definition and possible solutions;(2)Blockchain applications in solid waste management;(3)blockchain applications for different solid waste types;(4)blockchain elements for waste management;(5)blockchain in cooperation with other technologies.The author syntheses advanced sorting process,models of Blockchain in solid waste trading,and three use cases with selected granularity.The used design methodology is unified modelling language:activity diagrams and communication diagrams.The author applies the principles of supply and demand.The models are intended for business developers,university professors,and students.