Coke oven gas: Availability, properties, purification, and utilization in China

The global demand for energy is constantly on the rise because of population explosion, rapid urbanization, and industrial growth. Existing energy resources are struggling to cope with the current energy requirements. Aside from exploring renewable energy alternatives, available energy resources must be utilized to their maximum potential. Coke oven gas (COG) is highly rated as a valuable by-product of coal carbonization to produce coke in the steel industry. Typically, a single ton of coke generates approximately 360 m3 COG. China annually produces 70 billion N m3 COG; however, only 20% of the gas produced is utilized as fuel. Disposing COG without an effective recovery and efficient utilization is a serious waste of an energy resource and results in environmental pollution. COG is regarded as a potential feedstock for hydrogen separation, methane enrichment, and syn-gas and methanol production. It can also be effectively utilized to produce electricity and liquefied natural gas. The availability, properties, purification, and utilization of COG are reviewed in the current study. COG utilization routes are summarized in detail, with focus on some major industrial projects in China and other countries that are based on COG utilization technology.