Effects of Water Washing and Deashing on the Combustion Characteristics of the Zhundong Lignite

ABSTRACT

To examine the effects of water washing and acid-based deashing on the structure as well as combustion characteristics of Zhundong lignite, this study used high-speed planar laser-induced fluorescence measurements (OH-PLIF) with a specific burner and characterization techniques including XRD, BET, and ICP-AES as the method. The results indicated that both water washing and deashing can remove the ash and the main mineral alkali metals. Compared with RC, the total amount of OH release from WWC and UCC was increased attributing to the addition of combustibles and volatiles. The ignition of WWC and UCC was faster than that of RC, while the burning rate followed the opposite order. Experimental result confirms that the alkali metal and alkaline earth metals play a catalytic role in coal combustion. Meanwhile, the increase of the BET surface area and the reduction of ash are conducive to heat transfer, which is favorable for the ignition of pulverized coal.

KEYWORDS:

• OH-PLIF
• water washing
• deashing
• combustion characteristics of coal

Acknowledgments

We special thanks to Prof. Shi LIU at North China Electric Power University for useful discussions.

Disclosure statement

There is no potential conflict of interest.

Additional information

Funding

The National Key Technology Research and Development Program of the Ministry of Science and Technology of China under Grant NO.2015BAA04B02 supported this work;;