Published May 2012
China has started or planned several large commercial projects to produce ethylene and/or propylene by integrated coal-methanol-olefin processes or from outsourced methanol. If all planned projects materialize, China will add about 17.7 million metric tons of light olefins production capacity from coal or outsourced methanol by 2016, which will substantially increase its self-sufficiency of light olefins, reduce its reliance on imports of olefins and olefin derivatives, and reduce its dependence on petroleum for its chemical feedstock. The outcome of these projects will not only impact supply and demand dynamics for methanol, olefins, and polyolefins in China but also globally.
Several factors will determine the future level of success of the coal-to-olefin projects. Most important of all is process economic analysis of the relative competitiveness of these projects. This review estimates and analyzes the technology, production, and capital costs for Shenhua Baotou coal to olefins, Shenhua Ningxia coal to propylene, and Datang coal to propylene, the three leading coal-to-olefins projects that recently started commercial production. Process economics are presented at three integration levels: coal gasification, methanol production, and finally integrated olefins production. We also evaluate the economics of olefins production based on consumption of outsourced methanol such as Sinopec's Puyang project and compare the results to the economics of integrated coal-to-olefins production. In addition, we compare the process economics of coal and methanol-based projects to those of naphtha steam cracking and propane dehydrogenation technologies for propylene production.
Coal gasification consumes a large volume of process water and emits a large amount of carbon dioxide. This review also looks at these key environmental factors that will influence the future of coal-based olefins projects in China.