The Shanxi provincial Economy and Information Commission announced yesterday that China's first 50,000 Nm3/h coke-oven-gas-to-synthetic natural gas (SNG) demonstration unit will go into operation in the province by the end of this year. The unit uses SWRDICI patented technology. At the same time, feasibility studies of more than 20 projects have been completed and this will promote the better utilization of resources and energy diversification in China, while dealing with China's natural gas shortage and reducing chemical and greenhouse gas emissions.
Ma Yunxia, head of the Shanxi provincial Economy and Information Commission’s Energy Department, said that the Shanxi Guoxin Loujun New Energy Co, Ltd and SWRDICI recently signed a cooperation agreement on a coke-oven-gas-to-SNG project that uses oven from the coking process as raw material for SNG production. The facility has a 50,000 Nm3/h capacity and is scheduled for completion by the end of this year.
And, project costs will be a mere 30-40 percent of the cost of a similar capacity coal-to-natural gas project. It will be able to produce 200 million m3/yr of SNG, and will be connected to the Shanxi Guoxin Energy Development Group’s natural gas pipeline network. The project will reduce coke oven gas waste and cut 338,000 t/yr in carbon dioxide emissions, 1,210 t/a in sulfur dioxide, and 16 t/yr in dust. Building costs can be recovered within three years and it will play an exemplary role in promoting the utilization of coke oven gas in China.
Experts explained that the unit uses SWRDICI's patented coke-oven-gas-to-SNG technology, which grew out of a key government project as part of the 11th Five-Year Plan. It passed a Ministry of Science and Technology review earlier this year. The technology has three major innovations: first, a catalyst that allows it to complete methanation, deoxidation, and carbon hydrocarbon at the same time. Second, a methanation process with several levels for gas circulation and steam recovery to remove the reaction heat of methanation and allow for a more reasonable use of heat energy.
The third is that, by integrating coke-oven-gas-purification, methanation, and gas-separation technology through pressure swing adsorption, it can produce 99.99-percent pure hydrogen at the same time as SNG production. SWRDICI has signed technology transfer agreements with two Shanxi enterprises and has completed feasibility studies on more than 20 projects.
The technology has a number of possible coke-oven-gas applications, such as direct combustion, power generation, urea production, methanol production, natural gas production, and steel-making, with technological and economic analyses showing coke-oven-gas-based SNG production to be the most profitable. A 1m t/yr coking facility can produce 100 million Nm3/yr of compressed natural gas by the methanation of coke oven gas produced by the facility. China's coke industry can produce 20 billion m3/yr of coke oven gas in all, or the same amount as the total heating value of the natural gas transmitted by the first phase of the West-East natural gas project.
Reported by Xie Zhaoping