An Energy Efficiency Analysis of an Industrial Reheating Furnace and an Implementation of Efficiency Enhancements Methods

Abstract

Rapid consumption of energy resources, increasing energy needs, the competitive conditions in the industry and environmental concerns, all of those call for efficient use of energy resources. In this context, energy efficiency studies were carried out in a rolling mill of a reheating furnace of an integrated industrial enterprise. In studies, some important efficiency measurements were conducted, mass and energy balances were established by using the results of these measurements and the operating data of the plant along with energy saving opportunities, with the specified amounts and repayment periods were determined. Energy conservation studies that can be realized in the reheating furnace were considered including operation of the reheating furnace with the pertinent excess air coefficient, compensation of the air leakage losses in the recuperator and establishment of the economizer in the furnace. As a result of these investigations some saving opportunities were determined and a new recuperator, economizer and gas analyzer were installed in the reheating furnace leading in total of 2,913,924 kcal/h of energy savings. After the implementation of energy saving measures, reheating furnace efficiency was increased from 61.83% to 69.43%. Keywords:Reheating furnace, Energy analysis, Energy efficiency, Energy conservation, Waste heat recovery, Energy audit INTRODUCTIONToday, a significant portion of energy needs is met from fossil-based energy sources for the productions and other purposes. The growing industrialization and rapid technological developments result in huge amounts of energy consumptions. Due to the increase in energy usage and the raised consumptions of fossil fuels, we witness a high level of released carbon dioxide (CO 2 ) released to the atmosphere. To alleviate a cause greenhouse effect and climate change, we are and requires an efficient use of energy resources (Tütünoglu et al., 2011). When examining the situation from the perspective of industrial enterprises, the studies carried out to enhance the efficiency in the industry can contribute to save energy, energy resources, help to use of energy efficiently and reduce the environmental pollutions, significantly. Energy saving can be described as an auxiliary source of energy that is easy to convert, local, clean and cheap (Terzi and Baykal, 2011).Iron and steel industry is one of the most energy consuming industries in the world. This industry contributes to greenhouse gas (GHG) emissions to a large extent. Their energy consumption amount is around 24 EJ (24×10 18 J) per year, which corresponds to 5% of total energy consumption in the world (Xu and Cang, 2010).In an integrated iron and steel plant, one of the most intensive energy consumers is the reheating furnace. Reheating furnaces work continuously and they are used in hot rolling mills to heat the steel stock (billets, blooms or slabs) at the temperature around 1050-1300 ˚C (Topbas,, 1991). Due to working at high temperatures, reheating furnaces need to operate as efficiently as p...

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Performance evaluation of a walking beam type reheating furnace based on energy and exergy analysis

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