Regular Article

An applied study on energy analysis of a coke oven

¹ Directorate of Coke Facilities, Kardemir Iron and Steel Co., Karabuk, Turkey
² Energy Systems Engineering Department, Karabuk University, Karabuk, Turkey

^* Corresponding author: selcukselimli@karabuk.edu.tr

Received: 18 October 2023
Accepted: 19 December 2023

Abstract

In this study, the energy view of an oven of a 70-oven coke battery in an iron and steel plant was evaluated based on operating parameters and recommendations for improving efficiency were made. A mass and energy balance per coking period (p) was created for a coke oven. It was found that during each coking period, 51.2% of the energy input was used as coking heat. It is predicted that approximately 6.91% of the input energy can be recovered from flue gas into the combustion air. By recovering the heat from the flue gas into the combustion air, the efficiency of the coke oven can be increased to 58.11%. The heat of the coke oven gas can be recovered and converted into usable form, which accounts for 6.53% of the total energy input. With the dry quenching process, it is possible to recover around 24% of the energy used from coke. Improved oven insulation, heat recovery from coke and flue gases, and the dry quenching process can recover energy worth more than 25.19 GJ/p. The energy efficiency of the furnace was predicted to rise to 82.11% with coke dry quenching and to more than 88.64% with coke gas heat recovery and insulation upgrades. The potential economic savings are $2578, equivalent to a reduction in CO₂ emissions of 2.45 tons per coking period. The financial equivalent of emissions reductions from carbon trading could be $233 per coking period. Through the processes of dry coke quenching, coke gas (CG), and flue gas heat recovery and thermal insulation improvements of the coke battery, the total amount of recoverable energy can exceed 617,294 GJ/year.