Material Flow Analysis Of Iron In China's Construction

Since 2001,China has maintained its status as the largest iron consumer in the world.From 2001 to 2016,China had consumed 8.04 billion tons of crude steel.And the construction industry is China's largest iron consumption area.Dynamic analysis of the changing characteristics of iron stocks in construction will help grasp the potential of secondary resource recovery and provide scientific support for the recycling and related management of iron resources.Based on dynamic material flow analysis and life cycle distribution function,the iron stocks in China's construction from 1949 to 2016 and the theoretical scrap of iron in Chinese buildings from 2017 to 2035 are estimated in this paper.Finally,according to the S-shaped law of per capita consumption,to forecast the crude steel demand of China from 2017 to 2035.And to assess the impact of iron theoretical scrap on iron demand in future China's constru-ction.The results show that,in 2016,the iron stock in China's construction is 2.81 billion tons,of which the iron stock in rural residential construction is 280 million tons,accounting for 10.1% of the iron stock in China's construction,in other rural construction,the iron stock is 0.3 billion tons,accounting for 10%,in urban residential construction,1 billion tons,accounting for 35.5%,and in other urban construction,1.5 billion tons,accounting for 53.4%.The change trend of total iron stock in China's provinces at different stages coincides with the process of industrialization and urbanization in China.In 2015,Jiangsu,with the largest iron stock in construction,reached 295 million tons,accounting for 10.9% of the country,followed by Shandong,with 229 million tons,accounting for 8.5% of the country,and Tibet,the smallest province,with 4.5 million tons,accounting for only 0.2% of the whole country's iron stock in construction.After three stages of slow growth,stable growth and rapid growth,the iron stock in China's construction increased from 1.0 million tons to 2.81 billion tons,and the per capita iron stock in construction also increased from 0.2 kg per capita to 2.29 kg per capita from1949 to 2016.Influenced by the process of industrialization and urbanization,the per capita iron stocks in construction in the four major economic regions of China are obviously different.In 2016,the maximum per capita iron stocks in construction in eastern China were 2526.0 kg per capita,followed by 2128.0 kg per capita in northeastern China,1732.0 kg per capita in central China and 1605.0 kg per capita in Western China.Influenced by the differences in living environment and economic level between urban and rural areas,the per capita iron stock in urban and rural construction in China is significantly different.In 2016,the per capita iron stock in urban and rural areas reached 3145.0 kg per capita and 530.0 kg per capita.In the future,China will still be the largest consumer of crude steel in the world.In 2035,theoretical scrap of iron resources in China accounted for 71% of crude steel demand,while theoretical scrap of iron resources in construction was 0.6 billion tons,accounting for 12% of crude steel demand.