TY - JOUR
T1 - Experimental research on direct expansion heat pump flue gas waste heat recovery and humidification nitrogen reduction system
AU - Zhang, Qunli
AU - Huang, Haotian
AU - Zhai, Hongbao
AU - Zhao, Wenqiang
AU - Lü, Xiaoshu
N1 - Funding Information:
Supported by: The BUCEA Post Graduate Innovation Project ; The Fundamental Research Funds for Beijing University of Civil Engineering and Architecture ( X20026 、 X20027 ).
Publisher Copyright:
© 2023 Elsevier Ltd
PY - 2023/6/20
Y1 - 2023/6/20
N2 - In order to solve the heat loss and the pollution of gas boilers, a synergistic system consisting of waste heat recovery tower and air humidification tower is proposed. Increasing in moisture content of the air can inhibit the generation of nitrogen oxides and increase the dew point of the flue gas, which is beneficial to the utilization of the waste heat from the flue gas. More heat is absorbed by the humidification water at the fin heat exchanger after the flue gas enters the waste heat recovery tower, which enhances the heat and mass exchange process in the air humidification tower. But the performance of the heat pump was found to show a downward trend, indicating a competitive relationship between nitrogen oxides reduction and waste heat recovery. Under the optimal condition, the experimental system can reduce nitrogen oxides emissions by 62.35%, and the exhaust gas temperature can be reduced to 24.46 °C. The heat pump can recover 6.94% heat while maintaining a minimum nitrogen oxides emission of 39.66 mg/m3. The heat pump makes more heat from the fuel to enter the heating network, which improves the heating efficiency of the boiler system. The system can meet the high-efficiency and clean production requirements of the energy system at the same time.
AB - In order to solve the heat loss and the pollution of gas boilers, a synergistic system consisting of waste heat recovery tower and air humidification tower is proposed. Increasing in moisture content of the air can inhibit the generation of nitrogen oxides and increase the dew point of the flue gas, which is beneficial to the utilization of the waste heat from the flue gas. More heat is absorbed by the humidification water at the fin heat exchanger after the flue gas enters the waste heat recovery tower, which enhances the heat and mass exchange process in the air humidification tower. But the performance of the heat pump was found to show a downward trend, indicating a competitive relationship between nitrogen oxides reduction and waste heat recovery. Under the optimal condition, the experimental system can reduce nitrogen oxides emissions by 62.35%, and the exhaust gas temperature can be reduced to 24.46 °C. The heat pump can recover 6.94% heat while maintaining a minimum nitrogen oxides emission of 39.66 mg/m3. The heat pump makes more heat from the fuel to enter the heating network, which improves the heating efficiency of the boiler system. The system can meet the high-efficiency and clean production requirements of the energy system at the same time.
KW - Combustion-air humidification
KW - Gas boiler
KW - NOx emission reduction
KW - Synergy
KW - Waste heat recovery
UR - http://www.scopus.com/inward/record.url?scp=85152597268&partnerID=8YFLogxK
U2 - 10.1016/j.jclepro.2023.137000
DO - 10.1016/j.jclepro.2023.137000
M3 - Article
AN - SCOPUS:85152597268
SN - 0959-6526
VL - 406
JO - Journal of Cleaner Production
JF - Journal of Cleaner Production
M1 - 137000
ER -
