Name: FRANCISCO MELLO FONSECA
Publication date: 16/12/2024
Examining board:
Name |
Role |
|---|---|
| CARLA CESAR MARTINS CUNHA | Coorientador |
| JOÃO LUIZ MARCON DONATELLI | Coorientador |
| JOSE JOAQUIM CONCEICAO SOARES SANTOS | Presidente |
| OSVALDO JOSÉ VENTURINI | Examinador Externo |
| SILVIA AZUCENA NEBRA DE PÉREZ | Examinador Externo |
Summary: Internal combustion engines (ICEs) in thermal power plants located in regions with high temperatures and humidity, as is the case for some plants in Brazil, operate under preventive derating to avoid the occurrence of knocking. On the other hand, these engines reject a significant amount of heat to the atmosphere, primarily through exhaust gases, which can be recovered to produce chilled water for cooling and dehumidifying
intake air, aiming to increase power generation. A research and development project was conducted to design and install an experimental thermal system to evaluate performance improvements in a generating unit of a thermal power plant. This experimental thermal system was designed, its equipment acquired, installed, and instrumented
for testing purposes. The system is composed of an absorption chiller, which recovers heat from the engine’s exhaust gases, a cooling coil for conditioning the engine’s intake air, and a cooling tower to cool the chiller and assist the engine radiator. The described experimental thermal system was installed and coupled to one of the generating units equipped with a Wärtsilä 20V34SG engine, which generates 8.5 MW of electric power, considering the derating conditions caused by the hot and humid climate at the plant site. Preliminary studies predicted an increase in electric power generation, reaching up to 10 MW, representing more than a 17% increase in power output, without exceeding the maximum average cylinder pressure and maintaining wastegate valve control, in accordance with the manufacturer’s safety requirements for the ICE. Two experimental test campaigns were
conducted. This dissertation aims to present and discuss the procedures and results of these tests, demonstrating that during the experiments, the maximum average cylinder pressure was reached when the electric power output was 9.6 MW, representing nearly a 13% increase in power. The installed thermal system achieved a specific investment cost with savings of approximately 28% compared to recent investments in new generating sets, demonstrating the economic feasibility of the project.
Keywords: Internal Combustion Engine Power Plant; Waste Heat Recovery (WHR); Air Cooling and Dehumidification; Experimental Performance Evaluation.
