Evaluación técnicoeconómica de medidas de eficiencia energética de los hornos b-1 b-51 de ENAP Refinería Bío Bío.
Loading...
Date
2025
Journal Title
Journal ISSN
Volume Title
Publisher
Universidad de Concepción
Abstract
El presente informe analiza el desempeño operativo del sistema de combustión de los hornos B-1 y B-51 de la planta Topping y Vacío I de ENAP Refinería Bío Bío. A través de una revisión detallada de la disposición de equipos, el sistema de control, los instrumentos de medición y las condiciones reales de operación, se identificaron desviaciones relevantes respecto a las condiciones de diseño, las cuales representan oportunidades concretas de mejora. Entre ellas destacan las concentraciones elevadas de oxígeno (O₂) y la baja presión de alimentación de fuel gas en los quemadores Low NOx.
El análisis del oxígeno reveló diversas causas posibles, tales como la operación manual de los dámperes, la selección inadecuada del punto de operación de O₂ y la presencia de aire falso. Se detectó que los transmisores de flujo de aire asociados al lazo de control de los dámperes se encuentran descalibrados, lo que explicaría el paso a una operación manual en lugar de automática. Para determinar el punto óptimo de operación del oxígeno, se propone habilitar la funcionalidad dual del analizador de gases existente, permitiendo medir simultáneamente O₂ y monóxido de carbono (CO), lo que facilitaría la reducción de pérdidas tanto por exceso de aire como por combustión incompleta. Posteriormente, se cuantificó el ingreso de aire falso, analizando su efecto sobre la eficiencia térmica y la medición de O₂. Además, se estimó el potencial de reducción en el consumo de combustible al mitigar estas infiltraciones, proponiendo el uso de sellos industriales.
Respecto a la presión de alimentación de fuel gas en el horno B-1, se identificó una pérdida del 36 % entre el transmisor de presión PIT0014 y el manómetro localizado en la entrada de los quemadores. Para abordar esta problemática, se analizó el perfil de presión dividiendo la línea en tramos según su diámetro, identificando como crítico el último tramo de 1”, adyacente a la conexión de los quemadores. Se propone reemplazar este segmento por una tubería de 1½”, con lo cual la caída de presión se reduciría a un 21 %, permitiendo operar dentro del rango recomendado por el fabricante.
Finalmente, se evaluaron los impactos económicos y ambientales de las mejoras propuestas. A través de un análisis de sensibilidad, se estimaron ahorros de combustible de hasta un 2,06 % y reducciones de emisiones de CO₂ de hasta 123 toneladas por período analizado. El retorno de la inversión se proyecta entre 6 y 41 meses, lo que respalda la viabilidad técnica, económica y ambiental de las medidas planteadas.
This report analyzes the operational performance of the combustion system in furnaces B-1 and B-51 of the “Topping y Vacío I” unit at ENAP Refinería Bío Bío. Through a detailed review of equipment layout, control systems, measurement instruments, and real operating conditions, significant deviations from design specifications were identified, each representing concrete opportunities for improvement. Notable findings include elevated oxygen (O₂) concentrations and insufficient fuel gas pressure in the Low NOx burners. The oxygen analysis revealed several potential causes, such as manual damper operation, improper O₂ setpoint selection, and the presence of false air. It was determined that the airflow transmitters associated with the damper control loop are uncalibrated, likely prompting the shift to manual control. To define the optimal O₂ operating point, it is recommended to enable the dual functionality of the existing gas analyzer to measure both O₂ and carbon monoxide (CO) simultaneously, facilitating the reduction of energy losses due to excess air and incomplete combustion. Subsequently, the entry of false air was quantified, and its impact on thermal efficiency and oxygen readings was assessed. A potential fuel savings estimate was developed by evaluating the effect of minimizing false air infiltration through the implementation of industrial sealing solutions. Regarding fuel gas supply pressure to furnace B-1, a pressure drop of 36% was observed between pressure transmitter PIT0014 and the local pressure gauge at the burner inlets. To address this, a pressure profile analysis was conducted by dividing the fuel line into sections based on diameter, identifying the final 1” segment near the burner connection as critical. A replacement with 1½” piping is proposed, which would reduce the pressure drop to 21% and enable operation within the manufacturer’s recommended pressure range. Finally, the economic and environmental impacts of the proposed improvements were evaluated. A sensitivity analysis estimated fuel savings of up to 2.06% and CO₂ emission reductions of up to 123 tons per analyzed period. The projected return on investment ranges between 6 and 41 months, supporting the technical, economic, and environmental feasibility of the recommended measures.
This report analyzes the operational performance of the combustion system in furnaces B-1 and B-51 of the “Topping y Vacío I” unit at ENAP Refinería Bío Bío. Through a detailed review of equipment layout, control systems, measurement instruments, and real operating conditions, significant deviations from design specifications were identified, each representing concrete opportunities for improvement. Notable findings include elevated oxygen (O₂) concentrations and insufficient fuel gas pressure in the Low NOx burners. The oxygen analysis revealed several potential causes, such as manual damper operation, improper O₂ setpoint selection, and the presence of false air. It was determined that the airflow transmitters associated with the damper control loop are uncalibrated, likely prompting the shift to manual control. To define the optimal O₂ operating point, it is recommended to enable the dual functionality of the existing gas analyzer to measure both O₂ and carbon monoxide (CO) simultaneously, facilitating the reduction of energy losses due to excess air and incomplete combustion. Subsequently, the entry of false air was quantified, and its impact on thermal efficiency and oxygen readings was assessed. A potential fuel savings estimate was developed by evaluating the effect of minimizing false air infiltration through the implementation of industrial sealing solutions. Regarding fuel gas supply pressure to furnace B-1, a pressure drop of 36% was observed between pressure transmitter PIT0014 and the local pressure gauge at the burner inlets. To address this, a pressure profile analysis was conducted by dividing the fuel line into sections based on diameter, identifying the final 1” segment near the burner connection as critical. A replacement with 1½” piping is proposed, which would reduce the pressure drop to 21% and enable operation within the manufacturer’s recommended pressure range. Finally, the economic and environmental impacts of the proposed improvements were evaluated. A sensitivity analysis estimated fuel savings of up to 2.06% and CO₂ emission reductions of up to 123 tons per analyzed period. The projected return on investment ranges between 6 and 41 months, supporting the technical, economic, and environmental feasibility of the recommended measures.
Description
Tesis presentada para optar al título de Ingeniero/a Civil Mecánico/a.
Keywords
Eficiencia térmica, Combustión, Hornos, Refinerías de petróleo