Modeling on Thermal Efficiency and Nox Emission of Alkali Recovery Furnace Depending on Oxygen Content of Flue Gas

Yan Li; Zhen Hu; Ceng-Fei; Yun Qing-yu Dai

doi:10.7584/JKTAPPI.2020.10.52.5.31

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Modeling on Thermal Efficiency and Nox Emission of Alkali Recovery Furnace Depending on Oxygen Content of Flue Gas

30 October 2020. pp. 31-44

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Abstract

About the problem of low thermal efficiency of alkali recovery furnace in pulping mills, we carry out research on the problem from the perspective of optimization of thermal efficiency. First, we deduced the relationship between the thermal efficiency of thealkali recovery furnace and the oxygen content of flue gas, the CO content, the exhaust temperature, the carbon content of the soda ash. Then, by adjusting the set value of oxygen content, we got the relevant data of the heat loss variables under different working conditions. According to this data, the relationship between thermal efficiency and heat loss variables was converted into a thermal efficiency model only about the oxygen content of flue gas. Then, we used the penalty method to convert the thermal efficiency model into a composite thermal efficiency model that considers NOx emissions. According to the different emphasis on thermal efficiency and NOx emission concentration, BFGS quasi-Newton method was used for optimization test. Finally, we input the optimization results into the actual system. The operating results show that the thermal efficiency model and its optimization results can not only improve the thermal efficiency of the alkali recovery furnace, but also effectively reduce the NOx emissions.

Keywords

Alkali recovery boiler

Thermal efficiency

the oxygen content of flue gas

NOx

References

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Information

Publisher :Korea Technical Association of The Pulp and Paper Industry
Publisher(Ko) :한국펄프종이공학회
Journal Title :Journal of Korea TAPPI
Journal Title(Ko) :펄프종이기술
Volume : 52
No :5
Pages :31-44
Received Date : 2020-06-22
Revised Date : 2020-09-27
Accepted Date : 2020-09-30
DOI :https://doi.org/10.7584/JKTAPPI.2020.10.52.5.31

Journal of Korea TAPPI ISSN:0253-3200(Print) 펄프종이기술

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Literature Cited