重庆市钢铁存量估算及驱动力分析

钢铁存量的准确估算可为预测钢铁需求量、理论报废量、制定资源环境管理政策提供科学依据。本文以重庆市全行政区面积为研究边界,采用自下而上的方法估算了1985—2014年重庆市钢铁存量及其行业分布。研究结果表明,重庆市的钢铁总存量及人均存量在过去30年间分别增长了10倍和12倍,于2014年分别达到0.59亿t和1748kg/人;在钢铁存量的行业分布结构上,建筑钢铁存量的历年占比均达到50%以上,该结果与邯郸市、美国纽黑文市的钢铁存量行业分布模式相似。基于钢铁存量的估算结果,本文利用IPAT模型对重庆市钢铁存量的变化进行了驱动力分析,研究发现,经济发展与人口增长是重庆市钢铁存量增长的主要驱动因素,其中经济发展始终是最强劲的驱动力,而技术的负向作用表明,重庆市未来对钢铁的需求将降低。

In-use iron and steel stock estimation and driving force analysis in Chongqing

A precise accounting of urban iron and steel stocks could provide scientific basis for predicting future iron (including steel) demand, forecasting scrap steel generation, and informing relevant resource and environmental management strategies and policies. Studies on in-use stocks at city level, especially in China, have far less been paid attention to by scientific community comparing to them at country level, although it is still crucial to solve urban waste management and resource recycling problem. Chongqing, one of the four municipalities in China, is a representative city in West China with the largest population between all Chinese cities. Hence, in this study, we selected Chongqing to estimate its in-use iron stock levels and its sector distribution from 1985 to 2014 by applying a statistics-based bottom-up approach within its whole administrative boundary. A huge effort was made to establish a more elaborate iron and steel containing product inventory and collect data of product amount and iron intensities of each product. Social-economic drivers of stocks growth were further analyzed by IPAT equation that could easily quantify the impact for each factor. Our main findings include: (1) Both total and per capita iron stocks have increased by more than 10 times in the last 30 years and reached 59 million tons and 1.748t/cap in 2014, respectively. (2) Chongqing shows the lowest iron and steel stock among it and other two cities reported in the literature (Handan, China and New Haven, USA). However, it has similar distribution structure among different sectors (e.g., with the largest share in the building sector). (3) Economic growth and population positively contribute to stock growth. Alternatively, the technology shows a negative effect, leading to a decreasing trend for future iron demand in Chongqing.