Jiansu Mao

Lead In‐Use Stock

The 20th century was a time of rapidly escalating use of lead (Pb). As a consequence, the standing stock of lead is now substantial. By linking lead extraction and use to estimates of product lifetimes and recycling, we have derived an estimate of the standing stock of lead throughout the century by top-down techniques. We find that the stock of in-use lead is almost entirely made up of batteries (68%), lead sheet (10%), and lead pipe (10%). Globally, about 200 teragrams (Tg) Pb was mined in the 20th century, and about 25 Tg Pb now makes up the in-use stock, so some 87% has been lost over time. Nonetheless, about 11% of all lead entering use was added to in-use stock in 2000, so the stock continues to increase each year. Currently, most of the stock is in Europe (32%), North America (32%), and Asia (24%). On a per capita basis, the global stock is about 5.6 kilograms (kg) Pb, and regional in-use stock ranges from 2.0 kg Pb (Africa) to 19.7 kg Pb (Europe). From a sustainability perspective, we estimate that the global lead resource is around 415 Tg Pb. Were the entire world to receive the services of lead at the level of the developed countries, some 130 Tg Pb would be needed, so there do not appear to be significant long-term limitations to the lead supply.

Losses to the environment from the multilevel cycle of anthropogenic lead.

As a component of a multi-level study of the anthropogenic lead cycle for year 2000 (52 countries, 8 regions, and the planet), we have estimated the lead flows in seven emission streams: tailings, slag, fabrication and manufacturing, dissipation from use, hibernation, landfilling, and dispersion following product discard. For every 1 kg of lead put into end use, 0.5 kg is lost to the environment, largely due to landfilling and dissipation from use. From the standpoint of the receiving media, 1/3 of the losses are to uncontained solids on land and 48% of the losses are to containment facilities on land. On a country basis, the largest losses occur in the United States and China, which between them are responsible for about 32% of total global lead losses. On a per capita basis, the highest lead losses occurred in the United Kingdom, Belgium-Luxembourg, and Ireland.

Industrial flow of lead in China

The rules on industrial flow of lead were studied for theoretical foundation of nonrenewable resource conservation and environmental improvement. A model of lead flow in lead product life cycle was developed through lead flow analysis and was used to analyze the relationship between lead product system and its environment, thus the rules on industrial flow of lead were obtained. The results show that increasing eco-efficiency will favor both resource conservation and environmental improvement. Several indices were proposed to evaluate the lead flow. As for application, the lead-flow for China in 1999 was analyzed and the reasons for low eco-efficiency were identified. In the end, some countermeasures were proposed to improve eco-efficiency, and the future lead ore consumption and environment quality were forecasted.

A dynamic analysis of environmental losses from anthropogenic lead flow and their accumulation in China

Abstract Substance flow analysis was applied to analyzing the lead emissions in 2010. It turns out that in 2010, for every 1 kg of lead consumed, 0.48 kg lead is lost into the environment. The emissions in 2010 were estimated to be 1.89×10 6 t, which were mainly from use (39.20%) and waste management & recycling (33.13%). The accumulative lead in 1960–2010 from the anthropogenic flow was estimated and the results show that the total accumulative lead in this period amounted to 19.54×10 6 t, which was equivalent to 14.26 kg and 2.04 g/m 2 at the present population and territory.

Changes in functions, forms, and locations of lead during its anthropogenic flows to provide services

Abstract Knowledge of the changes in a materials function, form, and location during the transfer and transformation of materials to generate human services will improve our understanding of how humanity interacts with the environment and of how services are formed by human activities. We compared leads anthropogenic and biogeochemical cycles and found that the services, pathways, and changes in form requiring the most attention. We traced lead through its life cycle and identified the changes in its functions, forms, and locations by examining technology and engineering information. Lead ore and scrap were the two main anthropogenic sources of lead. When lead provides human services, its main functions included the storage and delivery of electricity, anti-corrosion treatments, and radiation protection; the main forms of lead in these products were Pb, PbO 2 and PbSO 4 , and the main location changed from lithosphere in central China to regions in eastern China.

Lead anthropogenic transfer and transformation in China

Information on lead redistribution and speciation changes in anthrosphere can help to analyze the whole lead cycle on the earth. Lead life cycle was traced based on the concepts of anthropogenic transfer and transformation. Lead transfer and the distribution of chemical species throughout the anthropogenic flow were identified in 2010 in China. The results show that 1.85 Mt lead ore was consumed (besides 1.287 Mt imported concentrated ore and 1.39 Mt lead scraps. After undergoing transformations, 3.53 Mt lead entered end services in chemical species of Pb, PbO2 and PbSO4, altogether accounting for over 80% of the total lead products. Finally, 2.10 Mt ore was emitted into the environment in such species as PbSO4 (26%), PbO (19%) and Pb (15%). Lead transfer begins in primary raw material sectors, and then transfers to manufacturing sectors. Lead provides services mainly in such industrial sectors as transportation, electrical power and buildings or construction.

Risk assessment of lead emissions from anthropogenic cycle

Abstract The risk assessment right from the source of emissions can effectively guide the pollution control. A model was established, consisting of four part: source estimation, environmental fate analysis, exposure analysis and risk assessment. The human health risk, ecological risk and total risk of lead emissions were assessed. The factors were estimated to indicate the environmental decrease and exposure probability. Of all the 1887 t emissions in China in 2010 (quantified in the previous work), it is turned out 1.3 t reached human bodies (0.9 mg/ca), and 2.7 t reached the ecosystem. Lead mainly came from the Use stage for the source while lead causing risk mainly came from the Waste Management & Recycling and Production stages. As for chemical forms, PbO contributed most to the human health risk and PbSO 4 contributed most to the ecological risk. PbSO 4 , PbO and Pb altogether contributed 71% to the total risk, indicating these three chemicals should be taken priority for the risk management.

Circulation of Substances: Analysis of Logistics

To clarify the concept of mankind’s flow of material, this chapter will explore how material flows in the human socio-economic system and how the flow may be managed and optimized. Through the discussion in the previous chapters, we find that there are different environmental problems in different regions, and different environmental problems involve different types of substances. The natural circulation process of different material types and the process of human flow are also different. Beginning with the simplest material, scientific research is often performed with the principle of “simple and complex”; therefore, this chapter selects a simple substance. Based on their relationship with modern social and economic development and the resources and environment of this type of material, we select metal substances as the representative material for this topic.

Circular Economy and Sustainable Development Enterprises

This textbook systematically addresses why and how Circular Economy should be developed and practiced by employing a Discussion and Research (D&R) teaching method. This method allows us to show the whole process of academic research, from formulating the key questions, to methodology design, and ultimately to conclusions and applications. In addition, the suggested class discussions and group homework provide good opportunities for participant cooperation and exchange. In this textbook, all chapters and sections are intended to answer specific scientific key or sub-key questions, while all chapters are also internally structured logically and systematically, from question to final conclusion. This textbook may help to boost student performance in science and research and was selected for inclusion in the 13th Five-Year planning teaching materials for regular higher education in China.

Circulation Flow of Material: Fixed-Point Logistics Analysis

There are two representative methods of material flow analysis: the tracking method that focuses on the material particle and the fixed-point method that focuses on a particular region. The previous chapter explored the tracking method of logistics analysis. This chapter will focus on the fixed-point method combined with the Yale University logistics analysis framework to study the evolution of its scientific research process.