Quantifying carbon dioxide emission of coal chemical industry in China

Coupled with the rapid development of economy and the increasingly improvement of living standards, China has a huge rigid demand for basic chemical products and energy. Unlike many other countries which produce these... [ view full abstract ]

Coupled with the rapid development of economy and the increasingly improvement of living standards, China has a huge rigid demand for basic chemical products and energy. Unlike many other countries which produce these chemicals by transforming oil or natural gas, China relies primarily on coal as the feedstock due to China’s abundant coal resource and relatively scarce oil and natural gas reserves. Therefore, coal chemical industry is in a state of rapid development in China. At present, China is the largest producer of coal chemical products in the world. However, during the processes that coal is converted to various types of chemical products or fuels by chemical processing, vast amounts of carbon dioxide is discharged. Furthermore, coal chemical industry is energy-intensive which means large amounts of carbon emissions as well. China, as the largest contributor of carbon dioxide emissions in the world, are under huge pressure to reduce emissions. In order to mitigate the contradiction between the development of coal chemical industry and carbon emission reduction in China, it is necessary to quantify the CO₂ emission of coal chemistry industry. But so far the carbon emission from coal chemistry industry is still not assessed accurately. In this study, we collected production data of twenty-six representative coal chemical projects by field investigation and established carbon emission factors of main eight coal-based chemical products by ten typical coal chemical processes. The assessment of the coal chemical carbon emissions is studied on three separate resources: process-derived CO₂, fuel-derived CO₂, electricity-derived CO₂. Based on the emission factors, we evaluated the carbon emission of coal chemical industry from each province in 2015. The result shows carbon dioxide emission from coal chemical industry is 683 million tons, which accounts for 6.6% of China’s total carbon emission. Coal-to-ammonia, coal-to-coke, coal-to-methanol and coal-to-urea are the main carbon emission contributors and count 28.26%, 24.84%, 20.57%, and 14.96%, respectively. But modern coal chemical industry may become important carbon emission contributor in the future, taking consideration of its enormous development foreground. Besides, carbon emission from coal chemical industry presents obvious regional differences. Shandong, Shanxi and Inner Mongolia are the largest three carbon emission emitters from coal chemical industry, accounting for one-third of total carbon emission. The regional differences of carbon emission implied that the coal chemical projects are mostly concentrated in the area which has abundance of coal resource. And the market demand for coal chemical product is also an important factor which can affect the distribution of coal chemical enterprises.