Biocoke has the potential to reduce the fossil-based materials in metallurgical processes, along with mitigating anthropogenic CO2- and greenhouse gas (GHG) emissions. Reducing those emissions is possible by using bio-based carbon, which is CO2-neutral, as a partial replacement of fossil carbon. In this paper, the effect of adding 5, 10, 15, 30, and 45 wt.% biomass pellets on the reactivity, the physicomechanical, and electrical properties of biocoke was established to assess the possibility of using it as a fuel and reducing agent for a blast furnace (BF) or as a carbon source in a submerged arc furnace (SAF). Biocoke was obtained under laboratory conditions at final coking temperatures of 950 or 1100 °C. Research results indicate that for BF purposes, 5 wt.% biomass additives are the maximum as the reactivity increases and the strength after reaction with CO2 decreases. On the other hand, biocoke’s physicomechanical and electrical properties, obtained at a carbonization temperature of 950 °C, can be considered a promising option for the SAF.

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This review aims to show the significance of the use of secondary carbon bio-carriers for iron and steel production. The term ‘secondary carbon bio-carriers’ in this review paper refers to biomass, torrefied biomass, biochar, charcoal, or biocoke. The main focus is on torrefied biomass, which can act as a carbon source for partial or complete replacement of fossil fuel in various metallurgical processes. The material requirements for the use of secondary carbon bio-carriers in different metallurgical processes are systematized, and pathways for the use of secondary carbon bio-carriers in four main routes of steel production are described; namely, blast furnace/basic oxygen furnace (BF/BOF), melting of scrap in electric arc furnace (scrap/EAF), direct reduced iron/electric arc furnace (DRI/EAF), and smelting reduction/basic oxygen furnace (SR/BOF). In addition, there is also a focus on the use of secondary carbon bio-carriers in a submerged arc furnace (SAF) for ferroalloy production. The issue of using secondary carbon bio-carriers is specific and individual, depending on the chosen process. However, the most promising ways to use secondary carbon bio-carriers are determined in scrap/EAF, DRI/EAF, SR/BOF, and SAF. Finally, the main priority of future research is the establishment of optimal parameters, material quantities, and qualities for using secondary carbon bio-carriers in metallurgical processes.

A large amount of finely dispersed manganese ore left after benefication operations or blown out from the furnaces is unsuitable for direct use in electric furnaces and blast furnaces, therefore it is necessary to granulate it in order to have the efficient use of its fine ore particles in metallurgy. To make our research more of practical use, we found it is reasonable not only work over manganese fines sintering but also to attempt mitigating the negative effect on the environment produced by the further sintering and apply the biofuel within the total fuel mass. Under laboratory conditions, the studies have been carried out with the objective to obtain manganese sinter, in which wood biomass is applied, namely initial and pre-pyrolyzed, at temperatures of 673, 873, 1073 and 1273 K. The amount of biofuel in the sinter blend was 25 wt.%. It has been established that the biomass use causes the decrease in the specific capacity of the sintering plant. However, for the efficient manganese ores sintering process, the biofuel of high pyrolysis temperature of 1273 K is required. To achieve the specific capacity and the yield to be as high as those when coke breeze is only used, the amount of the biofuel for manganese ore sintering should be less than 25 wt.% of the solid fuel. Additionally, it has been revealed that the further increase in the biofuel ratio in the total fuel amount is possible on condition that its reactivity is decreased, or larger particles of the biofuel are used.

Перспективним напрямком утилiзацiї технiчного гiдролiзного лiгнiну є його застосування в металургiйному виробництвi, в першу чергу при пiдготовцi залiзорудної сировини i доменному процесi. Значний резерв при цьому зосереджений в агломерацiйному процесi. Для полiпшення паливних властивостей лiгнiну, а також для видалення, з можливiстю уловлювання, токсичних речовин, слiд здiйснити його попереднiй пiролiз. Експериментально вивчено вплив технiчного гiдролiзного лiгнiну рiзного ступеня пiролiзацiї на процес залiзорудної агломерацiї i властивостi отриманого агломерату. Вихiдний лiгнiн пiддавався попереднiй термiчнiй обробцi до кiнцевої температури 400, 600, 800 i 1000 °С без доступу повiтря. Спiкання агломерату за участю пiролiзованого лiгнiну проводили на лабораторнiй агломерацiйнiй установцi. Пiсля спiкання визначали мiцнiсть агломерату, дослiджували його макроструктуру. Хiмiчний склад зразкiв агломерату дослiджували методом рентгенофлуоресцентного аналiзу. В результатi проведених експериментiв визначена можливiсть замiни 25 % коксового дрiб'язку лiгнiном, попередньо пiролiзованим при температурi 800 °С. За таких умов основнi показники агломерацiйного процесу, такi як вертикальна швидкiсть спiкання, вихiд придатного продукту i питома продуктивнiсть установки, практично не змiнюються. Спостерiгається незначне зниження мiцностi агломерату на удар i на стирання, однак данi показники залишаються на технологiчно прийнятному рiвнi. Слiд зазначити, що при використаннi лiгнiну в якостi агломерацiйного палива виявляється тенденцiя до деякого зниження вмiсту залiза в агломератi. Дослiдження макроструктури агломерату показало збiльшення дiаметра пор при частковiй замiнi коксового дрiб'язку лiгнiном, причому з пiдвищенням температури пiролiзу лiгнiну, обсяг пор збiльшується. Проведенi дослiдження пiдтвердили можливiсть вирiшення актуальної екологiчної проблеми утилiзацiї технiчного лiгнiну, шляхом застосування його в агломерацiйному процесi з попередньою його пiролiзацiєю. Перспективним напрямком подальших дослiджень є розвиток способiв пiдготовки технiчного гiдролiзного лiгнiну до використання в залiзоруднiй агломерацiїКлючовi слова: утилiзацiя промислових вiдходiв, технiчний гiдролiзний лiгнiн, пiролiз, залiзорудна агломерацiя UDC 622.788:662.6/9:504

<p class="AMSmaintext">Dominating globally and within Ukraine, the blast-furnace practice for iron production requires iron ore sintering preparation wherein the significant amount of fossil fuel is consumed, accompanied by harmful emissions into the environment. Pursuing the purpose to mitigate this negative impact, we address the promising direction of biomass utilisation for a partial replacement of fossil fuels in iron ore sintering. This paper considers the benefits of fossil fuels substitution with biomass, the world practice of biomass utilisation in iron ore sintering and the scope of the biomass energy potential in Ukraine. The study for obtaining sinters with the use of raw biomass fuels (sunflower husk, walnut shell) and charcoal has been carried out via lab-scale sintering pot. The influence of various biomaterials types on the process of iron ore sintering have been investigated and the obtained sinter quality in comparison with the conventional types of the fuels allows establishing the feasibility of replacing 25 % of coke breeze by charcoal or by walnut shell. The sunflower husk application is possible if preliminary preparation of the material for increasing bulk density is assumed to be carried out, for instance, by pressing.</p>