The Open Fuels & Energy Science Journal

2018, 11 : 1-15
Published online 2018 February 28. DOI: 10.2174/1876973X01811010001
Publisher ID: TOEFJ-11-1

RESEARCH ARTICLE
The Effect of CaBr on Mercury Speciation in Flue Gas: An Experimental and DFT Study

Jun Zhong1 , Fangyong Li1 and Weijie Yang2, *

* Address correspondence to this author at the School of Energy and Power Engineering, North China Electric Power University, Baoding, China, Tel: 18331121421; Emails: ; 394890445@qq.com

ABSTRACT

Background:

Additives affect the formation of different mercury speciation in coal-fired derived flue gas.

Objective:

In order to study the effect of the additive CaBr2 content, the Ontario Hydro Method (OHM) method has been applied to analyze the mercury speciation at the entrance and export of denitration (SCR).

Method:

Density Functional Theory (DFT) has been used to study the adsorption of mercury halide on unburned carbon surface.

Result:

The results show that along with the increasing amount of additive CaBr2, there is an increasing trend of the ratio of Hg2+ in flue gas.

Conclusion:

CaBr2 addition contributes to oxidize Hg 0 to Hg2+ and increase the mercury concentration through SCR. DFT results indicate that the adsorption of HgBr and HgBr2 on unburned carbon surface is chemisorption, and Br-C bond is stronger than Hg-C bond, both these bonds are covalent interaction.

Keywords:

Additive CaBr, Mercury speciation, Flue gas, DFT, AIM, Ontario Hydro Method (OHM).