SUPER-HEATED STEAM DRYING: AN INNOVATION OF CLEAN COAL TECHNOLOGY FOR LIGNITE

摘要

Lignite is a low rank coal which has the disadvantages of high volatile, high moisture content, high ash content, low ash fusion temperature, serious pollution and low utilization ratio and so on.If raw lignite is burned directly, the serious environment pollution will generate and the construction and running costs of the electric power plant will increase.Drying and upgrading of lignite gain more interests in present due to the increased energy demand.A lot of disadvantages such as high energy consumption, high investment and poor safety exist in the lignite drying when using the traditional thermal drying, so the superheated steam drying technology for lignite is put forward. The small-scale experimental research and pilot-scale test research of the super-heated steam drying and hot air drying for lignite were carried out, and the results show that the drying efficiency of the super-heated steam is higher than the hot air at given conditions.A more innovative approach as a new lignite Super-heated steam Fluid bed low-rank Coal Upgrading (SFCU) is proposed by Energy Conservation Research Center of Shandong Academy of Sciences. The comparison between the superheated steam technology and the traditional thermal drying technology has been done and the results show the superheated steam drying technology has the advantages of low energy consumption, high safety and energy saving.In a word, the exploitation of the super-heated steam drying technology for lignite can promote the development of the energy and power industry, and this technology will have a great potential application.