Integrated conceptual design of heating system at a Swedish mining company

• Main Authors: Wang, Chuan, Nordgren, Samuel, Lindblom, Bo, Savonen, Stefan, Hansson, Robert, Larsson, Robert
• Format: Conference Object
• Language: English
• Published: LuleÃ¥ tekniska universitet, Energivetenskap 2009
• Subjects: Energy Engineering; Energiteknik; Malmberget
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-37282; https://doi.org/10.3303/CET0918019

LKAB Malmberget is a Swedish mining site located at Malmberget, Sweden. Seven boiler centers are located on north part of Malmberget. There are no connections in between these boiler centers, meaning that it is a decentralized heating system. The heat generated is to heat up buildings and for mine ventilation mainly during the cold periods. The heat is mainly provided from electric and oil boilers. However, most boilers under use are over 20 years old, and it is time to retrofit the boiler system and infrastructure. The purpose of this work is to design and optimize the heating system by the integrated concept. An optimization model based on the mixed integer linear programming (MlLP) has been developed to minimize the total heat production cost, including operation cost and investment cost. The model can be used to calculate how a given heat demand can be satisfied at the lowest possible cost. Four different technical options have been considered in a new centralized heating system. On the basis of data input and assumptions, modeling results indicate that a lower cost could be achieved when a waste heat recovery boiler is installed at the old pelletization plant to recover sensible heat from flue gas. This will lead to a remarkable electricity saving (around 70% saving) compared to the reference case. It has also been noticed that in the optimized cases, oil boilers should not be operated due to a higher price compared to electricity, and by estimation an annual reduction of 3000 ton CO2 and 4.5 ton NOx could be achieved. Godkänd; 2009; 20100211 (ysko)