Steel Converter Slag Research Articles

Methacrylic acid in situ modified steel converter slag/natural rubber composites: Resourceful utilization of steelmaking solid wastes

As a by-product of the steelmaking industry, the large-volume production and accumulation of steel converter slag cause environmental issues such as land occupation and dust pollution. Since metal salts of unsaturated carboxylic acid can be used to reinforce rubber, this study explores the innovative application of in-situ modified steel slag, mainly comprising metal oxides, with methacrylic acid (MAA) as a rubber filler partially replacing carbon black. By etching the surface of steel slag particles with MAA, their surface roughness was increased, and the chemical bonding of metal methacrylate salt was introduced to enhance their interaction with the molecular chain of natural rubber (NR). The results showed that using the steel slag filler effectively shortened the vulcanization molding cycle of NR composites. The MAA in-situ modification effectively improved the interaction between steel slag and NR molecular chains. Meanwhile, the physical and mechanical properties, fatigue properties, and dynamic mechanical properties of the experimental group with MAA in-situ modified steel slag (MAA-in-situ-m-SS) were significantly enhanced compared with those of NR composites partially filled with unmodified slag. With the dosage of 7.5 phr or 10 phr, the above properties matched or even exceeded those of NR composites purely filled with carbon black. More importantly, partially replacing carbon black with modified steel slag reduced fossil fuel consumption and greenhouse gas emission from carbon black production. This study pioneered an effective path for the resourceful utilization of steel slag and the green development of the steelmaking and rubber industries.

Effect of Weathering on Steel Converter Slag Used as an Oxygen Carrier.

Steel converter slag, also called LD slag, is a material that has been suggested for use as a low-cost oxygen carrier for chemical looping applications. Low-cost oxygen carriers are especially relevant for the conversion of solid fuels, which may contain large amounts of reactive ashes. Ash may limit the lifetime of the bed material, which is why a high-cost oxygen carrier will likely not be competitive. Applying LD slag on an industrial scale as an oxygen carrier makes the storage properties of the material highly interesting. LD slag has been known to be affected by weathering, thus limiting the possibilities of the material to be used in construction, e.g., as fillers in concrete. In this study, pretreated LD slag for use as an oxygen carrier was weathered outdoors for roughly 1.5 years in southwest Sweden. Afterward, the particles were characterized and used in a laboratory batch fluidized bed reactor system to evaluate the effects of storage on the oxygen carrier properties. It was found that the reactivity with the fuel of the weathered LD slag was similar to that of the original sample when used in a laboratory fluidized bed. However, the physical properties were severely degraded due to weathering. Dissolved CaO formed CaCO3, agglomerating the top layer of the sample. The particles in the bulk of the sample were found to have decreased density and increased attrition rate. This suggests that LD slag particles for use as oxygen carriers should be stored dry to avoid weathering of the particles.

Solar-light-driven photocatalytic conversion of monosaccharide by oxygen-doped graphitic carbon nitride/artificial steel converter slag composite

The development of high performance, low-cost and resource-efficient photocatalysts with improved solar light harvesting capabilities can significantly enhance the practicability and viability of photocatalytic conversion of biomass-based substances to value-added chemicals. This work reports the construction of heterojunction between oxygen-doped graphitic carbon nitride and artificial steel converter slag (OCN/artCS) as efficient photocatalysts for conversion of biomass-derived monosaccharide to lactic acid under the simulated solar light. The OCN/artCS composites were facilely fabricated by the thermal polymerization of the mixtures of dicyanamide (DA) and oxalic acid (OA), which are precursors of OCN. The artCS acts as photocatalyst support for OCN to grow on its surface and can provide Ca2Fe2O5 semiconductor to possibly form the OCN/Ca2Fe2O5-containing artCS heterojunction. Compared with pristine OCN, the OCN/artCS composites exhibited higher photocatalytic performance for selective production of lactic acid, possibly due to the effective separation of photogenerated charge carriers after creation of OCN/artCS heterojunction. At the optimal content of artCS in the composites, the OCN/5%artCS delivered 99% glucose conversion and 90% lactic acid yield within 60 min at 50 °C under the simulated sunlight irradiation. This work can be a platform for the efficient utilization of industrial solid wastes for production of high-performance photocatalysts, enabling their promising applications in photobiorefinery and other photocatalytic processes.

Insight into the steel converter slag composite supported three-dimensional electro-Fenton remediation of landfill leachate

In this study, a green catalyst prepared by Co and salicylic acid-treated steel converter slag particles (Co-SAM-SCS) and intruding into an EF system (3D-SCS-EF) to treat organic matter and NH3-N in stabilized actual leachate landfill. The COD degradation depends on hydroxyl radicals (∙OH) by activation of BDD anodic catalysis and Co-SAM-SCS catalytic particles; The removal of NH3-N depends mainly on the indirect oxidation of ClO− produced by the carbon felt as the cathode; The product Fe3+ can be reduced to Fe2+ by the electrode, and it can be reused 5 times with an 82 % removal rate of COD. We obtained the optimum the device (particle size of 200–250 mesh, Co loading of 8:1, the dosage of 13 g/L, the anode of BDD); and the optimum operating conditions (initial chloride concentration = 3.12 g/, the current density of 1.5 A/cm2, aeration flow of 2 mL/min). The removal rates and of COD, NH3-N were 88.63 %, 89.47 % and energy consumption was 87.50 kW·h/kg COD, respectively. The TOC removal rate of the treated effluent reached 73.26 %, the biodegradability (BOD/COD5, B/C) value was increased from 0.25 to 0.33, the organic species were reduced, the removal of hard-to-degrade organic compounds was good, and the biochemical properties of the wastewater were improved.

Metal impregnation on steel converter slag as an oxygen carrier

AbstractOxygen carriers used in chemical looping processes operated with biofuel are affected by the inorganic matter of the fuel. It is therefore expected that the lifetime of the oxygen carrier is limited, and preferably low‐cost oxygen carriers should be used. Oxygen carriers based on iron ore or steel manufacturing waste products are available in significant quantities at low cost. However, it is common for these types of materials that their reactivity is low. This study investigates the effect of adding small amounts of more reactive elements into steel converter slag, also called LD slag.Slag particles were wet impregnated with 2 or 5 wt.% of Ni, Cu, Mn, or Ce. The new material's morphology was evaluated using X‐Ray Diffraction and SEM‐EDS. Changes in reactivity towards CO, CH4 and the model tar molecule benzene were evaluated using a bench‐scale laboratory fluidized bed reactor.It was observed that even small amounts of either Ni, Cu, or Mn could increase reactivity toward CO. Both Cu and Mn formed phases with LD slag that released oxygen via CLOU (chemical looping with oxygen uncoupling) and increased the conversion of methane and benzene. Ni and Ce doping also increased methane conversion but had only a minor effect on the benzene conversion. © 2023 The Authors. Greenhouse Gases: Science and Technology published by Society of Chemical Industry and John Wiley & Sons Ltd.

Phenol removal by activation of persulfate using magnetic carbon generated from sludge and steel converter slag

We obtained the best sample of Steel Sludge Carbon-Sludge Carbon (SCS@SC0.5–800 °C), which was subsequently used as a catalyst to activate persulphate for the removal of phenol. The batch experimental results illustrate the phenol removal efficiency reached 98.8% and the constants were 0. 25515 min−1 in the optimal SCS@SC0.5–800 °C/persulfate system (SCS@SC0.5–800 °C = 0.4 g/L; persulfate = 2 mM; phenol = 20 mg/L; pH=7). Increasing the reaction temperature increases the effectiveness of the system in removing phenol, and cations have a slight inhibitory effect on the removal of phenol from the system. Repeatability tests showed that after the third cycle, the phenol removal rate decreased from 88.6% to 65.2%, and the kobs decreased from 0.12567 min−1 to 0.03105 min−1. These results may be explained by the fact that active ingredients such as Fe0 are constantly removed from the solution, reducing the efficiency of the degradation process. The removal mechanism suggests that phenol is enriched on the graphitic carbon surface and subsequently degraded by leaching Fe2+-activated persulfate to produce free radicals. This study details the preparation of optimal samples of this new green catalyst and broadens the scope and potential of the catalyst for practical applications.

Interaction behavior of sand-diluted and mixed Fe-based oxygen carriers with potassium salts

Oxygen carriers, in the form of metal oxide particles, are bed materials that transport oxygen in solid form in fluidized bed applications, such as in chemical-looping applications. In biofuel applications, it is well known that alkali from the fuel ash can react with the bed material and cause, among other operation issues, agglomeration. When using oxygen carriers in a fluidized bed, it is likely that the bed material is either a mixture of different metal oxide materials or partly diluted with sand. This is to improve or combine the chemical properties of the materials used or simply for economic reasons.This work investigates how three potassium salts K2CO3, K2SO4 and KH2PO4 interact with the oxygen carriers: Steel converter slag (LD slag), ilmenite, mixtures of the two and each carrier diluted with silica sand. The salts were used as model compounds that can occur in biofuel ash. The set-up used was a fixed bed where a small sample of bed material is mixed with a potassium salt equivalent to 4 wt-% of potassium. The mixture was then exposed to reducing (H2 in steam) conditions at 900 °C during several hours in a tubular furnace. This provides a worst-case scenario for solid–solid interaction in a fluidized bed. If a solid–solid reaction does not take place in this setup, it will most likely never occur in a fluidized bed.When LD slag and ilmenite were combined, the potassium from the salts would prefer to accumulate in the ilmenite rather than the LD slag. Ca from LD slag interacted with KH2PO4 resulting in a less severe agglomeration than when ilmenite was used separately with the same salt. When the oxygen carriers were diluted with silica sand, potassium salt interaction resulted in agglomeration for both the oxygen carriers with all potassium salts. K2CO3 and K2SO4 formed potassium silicates, while KH2PO4 formed a phosphorus-containing melt. When LD slag was present, phosphorus was located in a K-Ca-P phase that was not present if ilmenite was present.

A magnetic sludge carbon combined persulfate-based ISCO system for leachate-contaminated groundwater remediation

Activation of persulfate by a green magnetic Steel Converter Slag-Sludge Carbon composite (SCS@SC) and subsequent remediation of actual leachate wastewater was studied in an intermittent reactor and column system to assess the potential of the persulfate-based in situ chemical oxidation (SR-ISCO) system for combined oxidative-reductive removal of organic contaminants from groundwater. In the batch experiment, an iron leaching concentration of 6942 mg/L, was higher than 223.2 and 124.4 times that of steel converter slag (31.14 mg/L) and sole sludge carbon (55.80 mg/L). In the column experiments, the total organic carbon (TOC) removal was maintained at 41.7 %, the loading rate reached 48.86 % with 15 g SCS@SC and 0.15 M persulfate after 400 min. The persulfate consumption, sulfuric acid generation, free radical generation, and iron ions flow out under acidic conditions, which are consistent with TOC removal. The mechanism of persulfate activation and organic matter removal was discussed and proposed by electron paramagnetic resonance (EPR) and energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), transmission electron microscopy (TEM), and gas chromatography-mass Spectrometry (GC–MS) to characterize the chemistry of solid and aqueous phases. A mechanism for contaminant removal was presented, which involves free radicals of persulfate activation by zero-valent iron (Fe0) and iron carbide (Fe3C) and precipitation removal by iron oxides. According to the findings, a viable alternative method for the inexpensive synthesis of catalysts from solid wastes such as sludge and steel converter slag was developed.

Resource utilization of steel converter slag: Efficient degradation of typical organic flotation reagent α-nitroso-β-naphthol via the synergy of radical and non-radical pathways

The organic pollution generated during production and processing in the mining area seriously endangers the ecological security of the surrounding environment. In this study, degradation of α-nitroso-β-naphthol (αNβN), a typical organic flotation reagent in mining area, by using steel converter slag (SCS) as a low-cost catalyst was reported for the first time. The results showed that SCS + H2O2 could effectively remove αNβN from water solutions. In the system used in this study, more than 98.8 % of αNβN could be removed within 60 min. Based on the analysis of the experimental results, the synergistic mechanism of radical and non-radical pathways was proposed. The radical pathway mainly consisted of OH radical oxidation, while the non-free radical pathway consisted of 1O2 and electron transfer. Fe, bridging OH and terminal OH on the surface of SCS were the active sites for H2O2 activation. The removal performance of the system was not affected by common coexisting ions, and showed strong anti-interference ability. After 4 times repeated use, the removal efficiency still reached more than 83 %. HPLC-MS was used to analyze the intermediate products, while the changes in their toxicity effects were analyzed by microcalorimetry for the first time. The results showed that the system could effectively reduce the ecotoxicity of a water solution containing αNβN. This study provides not only a new strategy for treating organic pollution in mining areas, but also a new idea for the green cycle development of industry and mining from the perspective of “treat the wastes with wastes”.

Analysis of the use of magnesium-containing additives in the charge of iron flux in order to reduce CO2 emissions

The growing requirements for the quality of finished steel products oblige to obtain steel with a low content of harmful impurities, especially sulfur. The main charge for steel production in the conditions of JSC EVRAZ NTMK is vanadium iron, the external desulfurization of which leads to large losses of valuable vanadium. Therefore, the smelting of iron with a low sulfur content is an urgent task. The main way to reduce sulfur in iron is to increase the basicity of the slag (B2), but MgO is the best desulfurizer. The paper evaluates the effectiveness of the use of various magnesium-containing materials in the conditions of the blast-furnace stage of JSC EVRAZ NTMK, taking into account CO2 emissions. The possibility of replacing limestone in the iron flux charge with dolomite, as well as with steel converter slag, is considered. Both materials will increase the proportion of MgO in blast-furnace slag, however, the use of dolomite is accompanied by a two-fold increase in CO2 emissions compared to limestone. Converter steel slag (CSS) does not contain carbonates, thus eliminating the formation of CO2 during the limestone decomposition. An additional advantage of CSS is its high content of valuable vanadium and manganese. The effect of an increase in MgO in slag on its melting point is considered. It has been established that an increase in the proportion of MgO to 14% will not cause difficulties in the processing of blast-furnace smelting products and will reduce the sulfur content in iron and the formation of titanium carbides and carbonitrides.

Magnetic-activated carbon composites derived from sludge and steel converter slag for wastewater treatment

It is generally challenging to design efficient, low-cost, and environmentally friendly persulfate catalytic materials for wastewater purification. We report a simple strategy to synthesize a steel converter slag-sludge carbon catalyst with steel converter slag as a template, suspended sludge as a precursor, and one-step pyrolysis. A persulfate activator was used to remove phenol and organic matter from actual wastewater leachate. The catalyst had a shell structure, a large surface area, abundant adsorption groups, and polymetallic catalytic capacity. The catalytic capacity depended on zero-valent iron (Fe0), which effectively leached active Fe2+ composite to produce hydroxyl and persulfate radicals by activating persulfate. The maximum phenol degradation was 94.5% in 55 min with 2 mM persulfate, 100 mg/L catalyst, and 20 mg/L phenol, which was 6 and 44 times greater than that of pure sludge carbon and steel converter slag, respectively. For actual wastewater leachate, the maximum removal rate of total organic carbon was 77.75% with 0.15 M persulfate, 50 g/L catalyst, and 1125 mg/L total organic carbon; all the fluorescent substances were removed. This work provides a new approach for designing persulfate catalysts derived from green resources. Further, our approach is practical for the treatment of wastewater that has high concentrations of organic material.

Tar characteristics generated from a 10 kWth chemical-looping biomass gasifier using steel converter slag as an oxygen carrier

Tar management is one of the key components to achieve high energy efficiency and low operational costs connected to thermal gasification of biomass. Tars contain a significant amount of energy, and unconverted tars result in energy efficiency losses. Also, heavy tars can condense downstream processes, resulting in increased maintenance. Dual fluidized beds for indirect gasification operated with active bed material can be a way to better convert and control the tar generated in the process. Using an active material to transport oxygen in an indirect dual reactor gasification setup is referred to as chemical-looping gasification (CLG). A higher oxidative environment in the gas phase, in addition to possible catalytic sites, could mean lower yields in comparison to normal indirect gasification.This paper investigates the effect of using Steel converter slag (LD slag), a byproduct of steel manufacturing, as an oxygen-carrying bed material on tar species generated in a 10 kWth dual fluidized bed biomass gasifier. The results are compared to the benchmark oxygen carrier ilmenite and conventional silica sand. Three different solid biofuels were used in the reactor system: steam exploded pellets, pine forest residue and straw. Tar was absorbed from the raw syngas using a Solid Phase Adsorption (SPA) column and was analyzed using GC-FID. Bench-scale experiments were also performed to investigate benzene conversion of LD slag and ilmenite at different oxidation levels.The findings of this study suggest that oxygen carriers can be used to decrease the tars generated in a dual fluidized bed system during gasification. Phases in LD slag possess catalytic properties, resulting in a decreased ratio of heavy tar components compared to both ilmenite and sand. Temperature and fuel load showed a significant effect on the tar generation compared to the circulation and steam ratio in this reactor system. Increased temperature generated lower tar yields and lower ratios of heavy tar components for LD slag in contrast to sand.

Steel Converter Slag as an Oxygen Carrier—Interaction with Sulfur Dioxide

Steel converter slag, also called Linz-Donawitz (LD) slag, has been considered as an oxygen carrier for biofuel chemical looping applications due to its high availability. In addition to its content of iron which contributes to its oxygen-carrying capacity, LD slag also contains a significant amount of calcium. Calcium, however, is known to interact with sulfur, which may affect the usability of LD slag. To get a better understanding of the interaction between sulfur and LD slag, batch scale experiments have been performed using solid and gaseous fuel with or without sulfur dioxide, together with LD slag as an oxygen carrier. The reactivity and sulfur interaction were compared to the benchmark oxygen carrier ilmenite. Sulfur increases the gasification rate of biofuel char and the conversion of CO for both LD slag and ilmenite. However, no effect of sulfur could be seen on the conversion of the model tar species benzene. The increased gasification rate of char was suspected to originate from both surface-active sulfur and gaseous sulfur, increasing the reactivity and oxygen transfer of the oxygen carrier. Sulfur was partly absorbed into the LD slag particles with calcium, forming CaS and/or CaSO4. This, in turn, blocks the catalytic effect of CaO towards the water gas shift reaction. When the SO2 vapor pressure was decreased, the absorbed sulfur was released as SO2. This indicates that sulfur may be released in loop-seals or in the air reactor in a continuous process.

Conversion of Steel Converter Slag into Anion Removing Agent via Alkali Fusion

Steel converter slag, a by-product of iron- and steel-making plants, was converted into a product containing hydrocalumite-like compound using the alkali fusion method. Most of the crystalline phase in the converter slag was converted into a soluble phase by the fusion method, and could be transformed into a product which included hydrocalumite-type crystals. The ability of the product to remove BO3 −, F−, PO4 3−, AsO2 −, AsO4 3−, SeO3 2− and SeO4 2− from aqueous solution is higher than that of raw slag, especially for BO3 −, AsO2 −, AsO4 3− and SeO3 2−.

Process Analysis of Chemical Looping Gasification of Biomass for Fischer–Tropsch Crude Production with Net-Negative CO2 Emissions: Part 1

Large-scale biofuel production plants require an efficient gasification process that generates syngas of high quality (with minimal gas contaminants and inert gases) to minimize the extent of the syngas cleaning processes required for liquid biofuel production. This work presents process modeling of the chemical looping gasification (CLG) process for syngas production. The CLG process is integrated with a Fischer–Tropsch synthesis (FTS) process to produce Fischer–Tropsch (FT) crude with net-negative CO2 emissions, enabling process and system-level analyses of this novel biomass-to-liquid process. CLG resembles indirect gasification in an interconnected circulating fluidized bed reactor, where instead of inert bed material, a solid-oxygen carrier, such as mineral ores rich in iron or manganese oxides, is used. The oxygen carrier particles undergo oxidation and reduction in the air reactor and fuel reactor, respectively, thereby providing heat and oxygen for gasification. This work uses data from CLG experiments performed with steel converter slag as the oxygen carrier and investigates its potential when integrated with different downstream gas cleaning trains and the subsequent fuel synthesis process with the primary objective of quantifying and evaluating the performance of the integrated CLG–FT process plant. Syngas with a high energy content of 12 MJ/Nm3 (lower heating value basis) is predicted with a cold gas efficiency of 73%. CO2/CO ratios, higher than indirect biomass gasification, are also predicted in the raw syngas produced; thus, there exists an opportunity to capture biogenic CO2 with a relatively lower energy penalty in the subsequent gas cleaning stages. This work quantifies other key performance indicators, such as heat recovery potential, negative CO2 emission capacity, and FT crude production efficiency of the CLG–FT plant. A 100 MWth CLG plant produces roughly 677–696 barrels per day of FT crude, with net-negative emissions of roughly 180 kilotonnes of CO2 annually.

Tar Characteristics Generated from a 10 Kwth Chemical-Looping Biomass Gasifier Using Steel Converter Slag as an Oxygen Carrier

Tar Characteristics Generated from a 10 Kwth Chemical-Looping Biomass Gasifier Using Steel Converter Slag as an Oxygen Carrier

Vanadium recovery from steel converter slag utilised as an oxygen carrier in oxygen carrier aided combustion (OCAC)

This study investigates vanadium extraction from steel converter slag from the LD (Linz-Donawitz) process. This slag has been used as an active bed material in a biomass boiler in a combustion technique called oxygen carrier aided combustion (OCAC). This usage in the boiler could be compared to the roasting step in the common roasting-leaching method for vanadium extraction. Leaching of LD slag prior to use as an oxygen carrier is undesirable as the materials active in OCAC are removed. This study successfully leached the slag following use in the combustion process. Two methods of leaching were utilised to compare the OCAC slag against traditional methods of vanadium extraction; a continuous flow leaching procedure and a microwave-assisted leaching procedure. It was found that a vanadium extraction efficiency of 22.1% could be achieved from the OCAC slag using 5 M sulphuric acid as a leaching solution following 30 min water leaching followed by 30 min of continuous acid leaching. Using the microwave-assisted method and further optimising leaching conditions, a final efficiency of 49.1% was achieved with 4 M sulphuric acid and particle size within the range of 44–74 μm.

Ladle-Furnace-Slag Reprocessing at Evraz Nizhnii Tagil Iron and Steel Works OJSC

Ladle furnaces at Evraz Nizhnii Tagil Iron and Steel Works OJSC produce over 90,000 metric tons of slag per year. As this slag cools, it turns into a fine-grained powder; if the powder cannot be sold, it is temporarily stored until it can be disposed of [1]. We have considered producing easily used flux sinter from the slag generated during ladle processing of steel (hereinafter, ladle-furnace slag or LFS). Since LFS still contains a large number of metallic inclusions, it cannot be included in sinter fed into a hammer mill via the enclosed lime feed trough. LFS was therefore added to the iron flux charge along with the steel smelting fluxes in a duplex and mono process (steel converter slag (SCS) and vanadiumbearing converter slag (VCS)); the fluxes are then crushed in a jaw crusher. A successful test of the use of LFS in sinter was performed, the charge was free of raw limestone, coke consumption was lower, sinter machinery production capacity was higher, and the weight/sample ratio of the sintered product was improved. Since SCS and VCS contain up to 3.0% V2O5, this provided an opportunity to increase vanadium use during the blast-furnace sintering process by more than 100 metric tons of vanadium per month.

Steel converter slag as an oxygen carrier for chemical-looping gasification

Chemical Looping Gasification (CLG) is a dual fluidized bed gasification technique where an oxygen carrier is used as bed material instead of sand. An optimized process could have several advantages, including i) one concentrated CO2 stream, amiable for carbon capture, ii) less tar formation, iii) additional reaction pathways for syngas production, iv) less corrosion and v) CO2 is generated in one stream from the fuel reactor that could be captured.Steel converter slag, also called LD slag, is a by-product from the steel industry which, besides iron, contains significant fractions of Ca, Mg, Al and Mn in a complex matrix of phases. The low cost and presence of known catalytic solid phases in the slag makes it interesting as an oxygen carrier in CLG.In this work, LD slag was investigated using a batch reactor with gaseous and solid fuel as well as with TGA. It was found that during gasification with LD slag, the material can i) transfer oxygen to the fuel, ii) catalyze the water-gas-shift reaction, iii) react with CO2 forming carbonates and iv) split water to hydrogen. The overall result was a raw gas with a higher H2/CO ratio for LD slag than the other tested materials.

Potassium Ash Interactions with Oxygen Carriers Steel Converter Slag and Iron Mill Scale in Chemical-Looping Combustion of Biomass—Experimental Evaluation Using Model Compounds

Chemical-looping combustion (CLC) is a combustion technology in which a solid oxygen carrier is used to convert fuel. The oxygen carrier is oxidized in air and subsequently transferred to a separate reactor in which it reacts with the fuel. The produced CO2 is inherently separated from the air components, making CLC a promising technology for carbon capture and storage (CCS). CLC of biomass combined with CCS (bioenergy CCS; BECCS) is a way to generate negative CO2 emissions and thus interesting for climate change mitigation. Undesirable chemical reactions between ash and oxygen carriers are a challenge in BECCS because of the reactive nature of biomass ash. This article examines two low-cost steel industry byproducts that have shown desirable fuel conversion properties in CLC: iron mill scale (Glodskal B) and steel converter slag (LD-slag). Their interactions with potassium ash model compounds (KCl, K2CO3,K2SO4, and KH2PO4) in a reducing atmosphere have been investigated. Mixtures of oxygen carriers and potassium salt have been reduced for 6 h in CO and steam in a laboratory-scale fixed-bed reactor at 850 °C. The reduced samples have been analyzed with SEM/EDS and XRD. The reactivity of the mixtures during reduction and oxidation has also been examined by thermogravimetric analysis (TGA). K2CO3 increased the reaction rate for the reduction of Glodskal and inhibited the reactivity of LD-slag. KH2PO4 formed a K−P−Fe component with apparent low melting temperature with Glodskal, causing agglomeration, and decreased the reduction/oxidation rate in TGA. KH2PO4 formed a K−P−Ca component with apparent high melting temperature with LD-slag causing agglomeration but the reduction rate was not affected. The study suggests that the iron mill scale and LD-slag should not be rejected as oxygen carriers for CLC based on potassium ash interaction.