Economic Analysis of Pyrolysis and Hydrolysis for SCR Flue Gas Denitrification Urea

doi:10.11930/j.issn.1004-9649.201704026

Abstract

Abstract: Because of its safety and convenience for transportation and storage in addition to its harmlessness to environment, urea has become a reliable substitute for liquid ammonia, a reducing agent for SCR flue gas denitrification in coal-fired power plants. The key part of the project to switch to urea from liquid ammonia is how to select suitable urea technology. In this paper, the investment cost and operation cost of urea pyrolysis process and urea hydrolysis process are analyzed through engineering modeling. The energy consumption level of urea ammonia production system is also studied by using thermodynamic method. The results show that the cost of urea hydrolysis is slightly higher than that of urea pyrolysis, but the operation cost is lower and the technical economy performance is better. The main reason for the high operation cost of urea pyrolysis is found out to be the low conversion rate of urea and the application of high quality electric energy as heat source.

Key words: coal-fired unit, flue gas denitrification, selective catalytic reduction, urea pyrolysis, urea hydrolysis

CLC Number:

TM621
X51

PEI Yukun, ZHANG Yang, XU Ketao, ZHU Yue. Economic Analysis of Pyrolysis and Hydrolysis for SCR Flue Gas Denitrification Urea[J]. Electric Power, 2018, 51(9): 174-178.

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URL: https://www.electricpower.com.cn/EN/10.11930/j.issn.1004-9649.201704026

https://www.electricpower.com.cn/EN/Y2018/V51/I9/174

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