Analysis of Energy Content and CO2 Emissions in Different Combinations of Coke-Using and Coke-Less Processes for Steel Production

Abstract

direct alloying with vanadium (DAV), EAF operation on scrap) that are performed in the course of producing steel. These processes were compared as part of an energy-environmental analysis by examining both energy content and a parameter that characterizes the emission of the greenhouse gas CO 2 -the technological greenhouse number (TGN). It was determined that the advantages in terms of energy content and CO 2 emissions belong to EAF steelmaking with the use of scrap, the DAV process, the HyL-3 -EAF process, and the Midrex -EAF process. It should be noted that the steel obtained in the DAV process is alloyed with vanadium. In each case, the processes that do not involve the use of molten pig iron in steel production should be given the highest priority based on their ratings for energy content and greenhousegas emissions.In [1-3], the energy content of the process of making steel by means of several alternative coke-less technologies was estimated and compared with the energy content of the traditional steelmaking process, which entails the agglomeration of ore-bearing materials and their subsequent smelting in blast furnaces to obtain pig iron for subsequent conversion into steel. In connection with the changes occurring in the Earth's climate and the worldwide effort to combat global warming, on September 30, 2013 Russian Federation President Vladimir Putin issued Decree No. 752 "On Reducing Emissions of Greenhouse Gases." It is thus important to analyze the different processes involved in obtaining steel in order to compare the end-to-end emissions of greenhouse gases (the so-called carbon footprint) and to use the technological fuel number (TFN) [3] to also compare the processes' energy content.There are two main types of greenhouse gases formed in the processes carried out in ferrous metallurgy: methane (CH 4 ) and carbon dioxide (CO 2 ). Methane is released during the mining of the raw materials used in metallurgical processes. The volumes of methane are independent of the processes that are used and are of a random nature. The methane that is formed in the course of metallurgical operations is a secondary energy resource (SER) and is burned as part of those operations. Carbon dioxide is formed during all of the industrial operations performed in metallurgy: here, it is formed by the combustion of organic fuels, the burning of carbon from semifi nished products, and the decomposition of the fl uxes that are used. Different technologies are characterized by the formation of different volumes of carbon dioxide. Thus, we will use a broader interpretation of the concept of carbon footprint and regard it as the integral (cumulative) end-to-end emission of

Extractive Industries as a Source of Greenhouse Gas Emissions and the Possibility of its Natural Sequestration under the Climatic Conditions of Central and Northern Eurasia

“…Each of the types of iron ore raw materials has a different carbon footprint. The integral CO 2 emission in the production of agglomerate is 319 kg/t of product, in the production of pellets -56.3 kg/t of product [Lisienko et al 2016]. This iron ore raw material (IORM) is supplied to metallurgical plants for the production of cast iron and steel.…”

“…The flows of raw materials and products of primary processing, taking into account the specific release of greenhouse gases, can be depicted in the form of a graph of CO 2 emissions. Figure 1 shows two options for the production of reduced iron: the blast furnace process and HYL-3 [Lisienko et al 2021, Lisienko et al 2016.…”