Foam Mixtures Research Articles

Optimized Eco-Friendly Foam Materials: A Study on the Effects of Sodium Alginate, Cellulose, and Activated Carbon.

This study focuses on optimizing the physical and mechanical properties of foam materials produced with the addition of sodium alginate as the matrix, and cellulose and activated carbon as fillers. Foam materials, valued for their lightweight and insulation properties, are typically produced from synthetic polymers that pose environmental risks. To mitigate these concerns, this study investigates the potential of natural, biodegradable polymers. Various foam formulations were tested to evaluate their density, compression modulus, and thermal conductivity. The results indicated that an increase in activated carbon content enhanced thermal stability, as indicated by higher Ti% and Tmax% values. Additionally, a higher concentration of sodium alginate and activated carbon resulted in higher foam density and compressive modulus, while cellulose exhibited a more intricate role in the material's behavior. In the optimal formula, where the sum of the component percentages totals 7.6%, the percentages (e.g., 0.5% sodium alginate, 5% cellulose, and 2.1% activated carbon) are calculated based on the weight/volume (w/v) ratio of each component in the water used to prepare the foam mixture. These results indicate that natural and biodegradable polymers can be used to develop high-performance, eco-friendly foam materials.

A novel foaming formulation with excellent salt-resistant for foam assisted deliquification of gas wells

In this paper, an excellent foaming formula for natural gas well deliquification was developed, which was based on the synthesized dodecyl ethylethanolamine (DEEA), commercially obtained cocamidopropyl betaine (CAPB) and sodium lauryl glutamate (SLG). The foaming properties and liquid unloading properties were studied, which showed that the optimal molar ratio of DEEA/CAPB/SLG ternary complex turned out to be 14:21:15. At a total concentration of 15 mM in the liquid phase, the optimal DEEA/CAPB/SLG mixture exhibited excellent foaming and liquid unloading capability at various conditions of methanol, condensate oil and salts contents and temperatures. At the methanol content of 45%, the foaming efficiency and liquid unloading efficiency of the DEEA/CAPB/SLG mixture were measured to be 100% and 25.5 ± 2.2%, respectively. When the condensate oil content was 10–30%, the liquid unloading efficiency ranged from 18.0 ± 2.1% to 25.0 ± 2.5%, which was much higher than that (8.3 ± 0.9%) obtained without condensate. The presence of salts retarded the performance of the DEEA/CAPB/SLG mixture, however, the addition of a chelating agent, trisodium nitrilotriacetic acid (NTA), to DEEA/CAPB/SLG could enhance the foaming efficiency and unloading performance at a salinity level of up to 41 × 104 mg/L, which might be the highest salt-resistant level of the gas well foaming mixture. The introduction of 10% methanol exhibited a positive effect on the DEEA/CAPB/SLG mixture’s foaming and liquid unloading performance against temperature (up to 90 °C). At 90 °C, the DEEA/CAPB/SLG foam could remove almost all the liquid from the column.

Development of insulating backfill materials produced from the ternary mixtures of red mud, fly ash and preformed foam

Many public utility lines to transport power, water, natural gas, water, sewer, and communication are placed beneath trafficable areas. However, insufficient or inadequate backfill induces sudden subsidence, damage, or pothole on the road. This study aims to develop lightweight controlled low-strength materials (CLSM) with low thermal conductivity using the ternary mixtures of red mud to replace aggregate sand, high carbon fly ash, and preformed foam. Changes in flow consistency, air void characteristics, bulk unit weight, unconfined compressive strength (UCS), and thermal conductivity (k) of the tested materials with varying red mud contents were investigated as a function of the foam volume ratio (FVR). The results demonstrate that the UCS and k of tested materials decreased with increasing FVR due the decrease in unit weight, and a greater UCS but smaller k was observed at a given FVR with increasing red mud content because the inclusion of red mud in the lightweight CLSM mix design helps improve the stability of air bubbles and achieve uniform distribution of air voids. In addition, the red mud can act as a NaOH supplier, leading to the developed material had additional strength gain from the alkali activation. Thus, the developed insulating backfill material showed 43 % decrease in k while maintaining UCS similar to non-foam CLSM without red mud.

The Impact of the Chlorhexidine Gel (WISDOM®) on Postoperative Sequelae Associated with the Surgical Removal of Impacted Mandibular Third Molars: A Randomized Controlled Clinical Trial

Background: One of the most prevalent procedures in oral surgery is the removal of impacted mandibular third molars, typically accompanied by trismus, edema, and pain. Several methods and biomaterials were implemented to mitigate or avoid these surgical problems. Objectives: To evaluate the efficiency of chlorhexidine gel (WISDOM®) in minimizing postoperative sequelae associated with the impacted mandibular third molar that will be surgically extracted and its role in promoting early soft tissue closure of the surgical site. Methods: The study design was a double-masked and randomized, controlled clinical study that included healthy patients needing the removal of a mandibular third molar through surgery. The participants were randomly assigned to two groups. The extraction site of the study group was filled with a mixture of gel foam and WISDOM®. In contrast, we filled the extraction sites of the control group patients with gel foam and sutured the surgical sites for both groups. The patients were evaluated on the first, third, and seventh postoperative days for pain, swelling, trismus, and early soft tissue healing. Results: Sixty eligible patients were enrolled in this study. The study group exhibited a statistically significant decrease in pain, edema, trismus, and early soft tissue healing on the first, third, and seventh postoperative days compared to the control group. Conclusions: WISDOM® gel can effectively reduce postoperative pain, trismus, and swelling and promote early soft tissue healing after surgical removal of an impacted mandibular wisdom tooth.

Evaluation of separation by high shear mixing for per- and poly-fluoroalkyl substances (PFAS) treatment in water

Widespread per- and poly-fluoroalkyl substances (PFAS) contamination in water, sediments and soils has driven demand for scalable and cost-effective treatments suitable for application across a range of ∑PFAS concentrations from ng/L to mg/L. One promising class of treatment technology is based on PFAS accumulation at the surface of air bubbles. In this study, hydrodynamic cavitation induced by high shear mixing generated colloidal gas aphrons (CGAs) made of different surfactants (cationic, anionic and non-ionic) to facilitate separation of PFAS differing in carbon–fluorine chain length, head group and charge. Separation efficiency was evaluated for a 600 µg/L ∑PFAS mixture of 6 PFAS each at 100 µg/L, and also for a solution spiked to 1 mg/L ∑PFAS with an aqueous film forming foam (AFFF) mixture. The choice of surfactant produced CGAs with different bubble sizes and surface properties; the non-ionic surfactant produced significantly smaller bubbles, while the cationic and anionic surfactant varied principally by charge. The ∑PFAS separation efficiency varied from < 30 % to 86 % using different surfactants after a 30 s process. The non-ionic surfactant was most effective overall, and the cationic surfactant was most efficient for short-chain PFAS, and those with the carboxylic head group due to surface charge compatibility. Zwitterionic precursor PFAS and perfluoroalkyl sulfonic acids species tested in this study were removed with > 90 % efficiency when anionic and non-ionic surfactants formed the CGAs, while short-chain perfluoroalkyl acids PFAA were removed similarly effectively by cationic surfactant-derived CGAs. While separation efficiencies were lower than the > 95 % ∑PFAS reductions reported elsewhere, the effect was achieved with a treatment time of 30 s, in contrast to the significantly longer treatment cycles applied in other studies.

Research on the performance of foamed concrete based on superhydrophobic bulk modification

Foamed concrete is a kind of lightweight insulation material formed by the uniform mixture of foam and cement slurry. The superhydrophobic bulk modification of foamed concrete can reduce its high water absorption and prolong its service life. In this paper, the compatibility of three hydrophobic agents named polydimethylsiloxane (PDMS), isoctyltriethoxysilane (ICTS) and SBT®-TIA with foams was studied, and the reasons of incompatibility were revealed. Then, the superhydrophobic bulk foamed concrete system was constructed by physical foaming method, adding polydimethylsiloxane (PDMS), calcium stearate (CS), nano-silica (NS) and covering the surface of the specimen with 200-mesh wire mesh. The results show that the maximum contact angles of the meshed surface and the internal polished surface of superhydrophobic foamed concrete were 162.7° and 153.5°, respectively. At the same time, the water absorption rate of the modified specimen was significantly reduced, and the reduction rate was up to 90 %. In addition, the deterioration degree of thermal insulation performance after soaking and the dry shrinkage rate were significantly reduced compared with ordinary foamed concrete. Scanning electron microscopy (SEM) revealed that increasing the multi-scale roughness could improve the hydrophobic properties of foamed concrete. Fourier infrared spectroscopy (FT-IR) also confirmed that low surface energy groups such as -CH2 and -CH3 in PDMS bonded to the cement hydration products, indicating the successful preparation of superhydrophobic bulk foamed concrete.

Tailoring microstructure and properties of porous mullite-based ceramics via sol-gel impregnation

Nanotechnology has been introduced into the refractory industry decades ago. However, there are still some peculiarities that hinder its routine application. Poor mechanical strength is one of them. Here we present the fabrication technique for mullite porous ceramics using a calcium-free colloidal binder system followed by secondary sol-gel impregnation intended for fabrication of large up-scaled monoliths. The primary foam was prepared via direct foaming of slurry containing colloidal silica, gelling agents, surfactant, silica fume, and different types of alumina. The foam mixture was cast, de-molded and dried using a cascade drying procedure. The investigation of mullitization that occurred during the high-temperature treatment was studied by XRD and TG-DTA analysis. The optimized sintering curve was then applied to obtain the highest mechanical properties. The resulting foam (with open porosity, volume density about 900 kg/m3 and mechanical strength about 10 MPa) was further processed by the impregnation step. The applied silica or combined silica/aluminum sol and unreacted alumina underwent secondary mullitization during following high-temperature treatment, which significantly enhanced the mechanical strength (up to 18 MPa). The secondary mullitization process was also investigated by HT-XRD and TG-DTA analysis. Foam microstructure was observed by an electron scanning microscope. Thermal conductivity of as-prepared ceramics foams varied from 0.3 to 0.4 W/m·K. The foam wall porosity evolution was studied by mercury intrusion porosimeter and estimated from image analysis.

Study on the fire extinguishing effect of compressed nitrogen foam on 280 Ah lithium iron phosphate battery

This study conducted experimental analyses on a 280 Ah single lithium iron phosphate battery using an independently constructed experimental platform to assess the efficacy of compressed nitrogen foam in extinguishing lithium-ion battery fires. Based on theoretical analysis, the fire-extinguishing effects of compressed nitrogen foam at different outlet pressures from foam mixture tanks were analyzed, examining factors such as battery surface temperature, flame temperature, and thermal weight loss. The results indicate that the compressed nitrogen foam can extinguish the open flame of the battery in 14 s at 0.7 MPa, with the battery's surface temperature dropping by approximately 11 % before and after the application of the extinguishing agent. Compared with other commonly used extinguishing agents, the compressed nitrogen foam demonstrates superior extinguishing efficiency, but its cooling efficiency is somewhat lower. At pressures ranging from 0.4 to 0.6 MPa, the foam displays prolonged drainage time and sustained cooling effects, rendering it more suitable for lithium-ion battery fire scenarios. To address the issue of reduced cooling performance during later stages of fire suppression by compressed nitrogen foam, an intermittent injection approach has been proposed to effectively preserve its cooling efficacy.

Fire Prevention in Buses Using Water Head and AWO System

Abstract: Buses can be designed to carry many passengers ,and in public places, incidents such as bus fires impose a relatively high threats to assets and lives. Hence, it is common to witness substainal casualties when a bus fire occurs .Fire diaster is common threat to lives and property . An IOT based automatic window opening system when smoke is detected by sensors is efficient one but ,this paper represents with a doubt if any one is struck on the bus ,this project helps to save their lives that keeping the steel pipes inside and outside of the bus and providing sprinkles and holes to the pipe In and Out side of the side of the bus in respectively. When some amount of fire/flame and smoke is detected by the sensors the water and foam mixture pass through the pipes and spreads over the bus.The rectangular water and foam storage tank is kept on the roof of the bus .The equipment here is the foam that can resists the fire so, Silicon Foam is the flame-retardant, self-extinguishing and can withstand 2100℃ flame .This project helps minimizing and delaying the spread of fire

Foam Mortar Layer in Soft Subgrade Embankment: A Review

Soils are the basis of the construction of civil engineering structures that are designed to support and withstand the weight of the structures above them. The main problems of soft soil include low bearing capacity and large settlement. In road pavements, the sub grade as the bottom layer of the road must have a good bearing capacity. Subgrade is a part that must be considered because of the weight of the pavement structure and the embankment above it. Soft soil conditions cause the need for reinforcement of the sub grade layer. Solving the problem of road construction is done by engineering so that the sub grade as the bottom layer of the road is safe and stable and has a good bearing capacity. The effort made to increase the bearing capacity of the subgrade is by reinforcing the soil (soil improvement). One of them is with lightweight material mortar-foam is an alternative construction material in soil reinforcement for road construction. Mortar-foam is formed from a mixture of foam, cement, sand and water. Research on foam mortars has been conducted in various places and countries in various ways and methods. This article will discuss the latest developments in the use of foam mortars as backfill in soft soils in the subgrade layer presented based on information provided by the author.

Investigation of a highly efficient foaming mixture compromising cationic Gemini-zwitterionic-anionic surfactants for gas well deliquification

Abstract Foamers with high resistance to condensate, salinity and high temperature play a crucial role in gas well deliquification. In this study, we developed an efficient foaming mixture containing a Gemini surfactant (CAGB), a betaine surfactant (CAPB) and sodium lauroyl glutamate (SLG), which exhibited excellent foaming performance (at a molar ratio of 3:3:4 and a dosage of 20 mmol L−1) with a foam volume of 440 mL and a half-life of 11 min. The optimized CAGB/CAPB/SLG mixture showed exceptional liquid unloading and foaming ability under high methanol (up to 40 vol.%) and condensate (up to 50 vol.%) content conditions. Trisodium aminotriacetate (NTA) facilitated the liquid unloading performance at a salinity of 90 g L−1. With 10 vol.% methanol, the liquid unloading rate of CAGB/CAPB/SLG foam at 90 °C could be increased to 90 %. Furthermore, surface tension and morphology analysis confirmed the presence of synergy within the CAGB/CAPB/SLG mixture in foaming, foam stabilizing and liquid unloading ability.

Experimental studies and computational exploration on an exceptionally salt/condensate resistant gas well foaming mixture compromising amino-betaine-ammonium surfactants and dodecanol

Liquid accumulation in natural gas wells is typically addressed by foam-based deliquification. This study systematically investigated the development of a green and cost-effective foaming mixture comprising lauramidopropyl trimethylammonium chloride (LATC), lauramidopropyl betaine (LAPB), sodium lauroyl glutamate (SLG) and dodecanol (LA). Properly combined LATC/SLG/LAPB/LA mixture demonstrated synergistic effects in enhancing foam generation, foam stabilization and liquid unloading. Remarkably, the LATC/SLG/LAPB/LA foam exhibited exceptional performance in unloading liquid, even at a condensate fraction of up to 50 %. Adding a chelator (NTA) to LATC/SLG/LAPB/LA further improved the foaming efficiency and liquid unloading performance at salinity levels of up to 33 × 104 mg/L, which was likely the highest salt tolerance according to the available literature. The negative effect of temperature on the performance of LATC/SLG/LAPB/LA foam was resolved by adding 15 % methanol. At 90 °C, almost all the liquid can be removed from the column by the LATC/SLG/LAPB/LA foam, which produced a liquid unloading efficiency of 90 % and a foaming efficiency of 100 %. Surface tension, viscosity and morphological analysis supported the observed synergistic effects, while molecular dynamic simulations revealed the mechanisms of the excellent salt/condensate resistance of the LATC/SLG/LAPB/LA foam. These findings demonstrated the promising potential of the LATC/SLG/LAPB/LA foam in gas well deliquification.

Experimental investigation on battery thermal management strategy applying water retention material

The thermal issue of the quantities of electronics especially batteries during practical application has always been a big concern. To better satisfy their heat dissipation demands in engineering application, a novel half-passive strategy applying water retention material was proposed in this research. The thermal management assembly containing silica pad, copper foam and water-diatomite mixture is attached on the surface of the constant heating source. Primarily, the effectiveness of the assembly was validated through comparative experiments, which turned out to lengthen the effective time by 125.6 %. Then, the effects of both internal and external control parameters including ambient environment, heating power, properties of the water-diatomite mixture, PPI (pores per linear inch) of the copper foam and mesh number of the diatomite were discussed on the heat dissipation ability evaluated by the maximum temperature (Tmax) and effective time (t). At last, the cooling performance with different intermittent spray mode of the assembly during longtime operation was investigated. Results showed that when heated with 11.0 W, the spray began at 45 °C and the intervals were set as 5 min, 7.5 min, 10 min with the water content in each spray of 3.0 g, 4.0 g, 5.0 g respectively were the most reasonable schemes, and the CF-D (copper foam-diatomite) assembly managed to control the maximum temperature around 46.0 °C. This novel design provides a practical reference for the further optimization on the battery thermal management system, which focused more on the cooling efficiency and control flexibility.

About Dynamics of Improving the Foam Concrete Technological and Operational Properties upon Disperse Reinforcement with Polypropylene Fibers

Introduction. The efficiency of the foam concrete products manufacture and application in construction is briefly overviewed. The reasons constraining the nomenclature of the manufactured products are listed. The information about evolvement of the foam concrete disperse fiber-reinforcement technology is provided. The need for scientific research aimed at studying the dynamics of the foam concrete technological and operational properties upon disperse reinforcement with polypropylene fibers is formulated.Materials and Methods. The composition and properties of the materials used for manufacturing the foam concrete mixtures are listed. The methods used for assessing the technological and mechanical properties of the materials under study are indicated.Results. The results of the experimental assessment of the polypropylene fiber length and amount influence on the dynamics of the plastic strengthening growth of the equally dense foam and fiber-reinforced concrete mixtures are presented. The scope of the polypropylene fiber influence on the dynamics of the studied mixtures plastic strengthening is analysed. The scientific substantiation of the reasons accelerating the mass transfer processes during the disperse reinforcement of mixtures with fibers is given. The results of the bending tensile strength tests of the large-size D600 concrete specimens are presented.Discussion and Conclusion. The efficient positive influence of the polypropylene fiber, in correlation with its length, on the following foam concrete properties has been distinguished:speed of phase transfer;ultimate extensibility;elasticity and strength modulus of D600 concrete.

Compressive Strength Investigations Of Foamed Mortar Incorporating Sandblasting Waste As Supplementary Cementitious Materials

Silica sand is one of the abrasive materials commonly used in the sandblasting process. The production of sandblasting waste is raising yearly, linear with the rapid development of the shipping industries. Silica sand was produced as by-product waste, approximately 400 ton per year. This research focused on compressive strength investigations of the foamed mortar incorporating silica sand as a supplementary cementitious material (SCM). Foamed mortar is a lightweight mortar made from a mixture of water, cement, sand, and foam, which can reduce the density of the mortar for construction purposes. Prior to use as SCM, the silica sand was pre-treated by using mechanical grinding to produce finer materials similar to cement. The observations were applied to pre-treated silica sand, such as chemical compositions, particle size analysis, normal consistency test, and setting time test. The specimens used in this research were mortar concrete with dimensions 5 x 5 x 5 cm and tested according to ASTM C579-01. The pre-treated silica sand varied from 10%, 20%, and 30% by weight of cement, were applied in this investigation. The compressive strength and spesific gravity were also observed. The results show that 20% cement replacement with pre-treated silica sand is the optimum composition and has 52.2 MPa in compressive strength at 28th days. These investigations conclude that pre-treated silica sand is potentially used as SCM in foamed mortars for sustainable concrete materials.

The Effect of Addition Superplasticizer (Sikament-LN) with Variation of Percentage on Compressive Strength Foamed Mortar Lightweight Materials

The foamed mortar (morbus) lightweight material consists of a mixture of sand, cement, water, and liquid foam (foam agent), which can improve the mechanical properties of clay soil and increase its bearing capacity. This research uses various variations of superplasticizer mixtures, namely by adding additional ingredients in the form of sikament-LN which will increase compressive strength by up to 40% at 28 days. This research needs to be carried out to determine the effect of sikament-LN on increasing the compressive strength of foamed mortar. The percentages of the sikament-LN mixture were 0.5%, 0.75%, 1%, and 1.25% with ages of 7, 14, and 28 days, each of which made 3 test objects in 4 variations of the mixture. The research results showed that the addition of sikament-LN to the 1.25% mixture did not meet the requirements because it produced a flowability of 23.5 cm and the mixture experienced a shrinkage of &gt; 20% when placed in a cylindrical mold. All foamed mortar specimens experienced an average dry density increase of 1.994% at a curing age of 7 to 14 days and an average dry density increase of 4.044% at a curing age of 7 to 28 days. In a mixture of 0.5%, 0.75%, and 1%, at 28 days the maximum compressive strength value obtained was 841,667 kPa (more than the required 800 kPa). For the sikament-LN mixture, a maximum of 1% of the cement weight is recommended so that the hardening process occurs in the foamed mortar test object.

Dynamics of foam glass structure formation using glass waste and liquid foaming mixture

Foam glass, a sustainable insulation material, enhances building energy efficiency and glass waste recycling. Liquid foaming agents allow achieving uniform pore distribution and reducing production energy costs. This study explored liquid “waterglass-glycerol” mixtures in foam glass synthesis, studying foaming dynamics from room temperature and 600 °C. It reveals waterglass inhibits glycerol evaporation, while glycerol suppresses waterglass foaming. The interaction between the foaming mixture and glass powder was examined. It was found that glycerol decomposition occurs regardless of the atmosphere, but it can be intensified in oxygen. he foaming process comprises pore nuclei formation (640–770 °C), pore growth (700–840 °C), and pore coalescence (840–900 °C). A comprehensive model for “glass powder-waterglass-glycerol” foaming was developed, describing processes in liquid mixture (water evaporation, structural changes in waterglass, glycerol liquid-to-gas transition and decomposition) and thermal changes in glass (sintering, melting, foaming, and foam collapse). Insights for industrial foam glass optimization were provided, emphasizing glycerol and waterglass by-product utilization and glycerol content reduction to enhance sustainability and efficiency.

Cellulose Fibers-Based Porous Lightweight Foams for Noise Insulation.

This paper examines effective and environmentally friendly materials intended for noise insulation and soundproofing applications, starting with materials that have gained significant attention within last years. Foam-formed materials based on cellulose fibers have emerged as a promising solution. The aim of this study was to obtain a set of foam-formed, porous, lightweight materials based on cellulose fibers from a resinous slurry pulp source, and to investigate the impact of surfactant percentage of the foam mixtures on their noise insulation characterisitcs. The basic foam-forming technique was used for sample assembly, with three percentages of sodium dodecyl sulphate (as anionic surfactant) related to fiber weight, and a standardised sound transmission loss tube procedure was used to evaluate noise insulation performance. Results were obtained as observations of internal structural configurations and material characteristics, and as measurements of sound absorption/reflection, sound transmission loss, and surface acoustic impedance. Based on the findings within this study, the conclusions highlight the strong potential of these cellulosic foams to replace widely used synthetic materials, at least into the area of practical noise insulation applications.

A novel salt and condensate–resistant foam co-stabilized by mixtures of surfactants and citric acid for gas well deliquification

Aged gas wells are often blocked by the accumulation of liquids, which can be removed by the injection of foaming surfactant mixtures. In this study, a compound foam stabilized by a quaternary mixture (alkyl amidoamine (amine), citric acid (acid), α–olefin sulfonate (AOS) and lauramidopropyl betaines (LAPB)) was firstly developed with the Waring blender method. The liquid unloading performance of this compound foam was then investigated to estimate its application potential under various condensate fraction, salinity and temperature conditions. At a condensate content range of 20 %–40 %, the amine/acid/AOS/LAPB foam is particularly effective in unloading the liquids. However, salinity was found to reduce the foaming efficiency (referred to as the ratio of the mass of the formed foam to that of the original liquid) and liquid unloading performance of the amine/acid/AOS/LAPB foam, which could be overcome through the addition of a chelator, namely nitrilotriacetic acid trisodium salt (NTA). Temperatures higher than 60 °C enhanced the performance of the amine/acid/AOS/LAPB foam. Synergistic effects within the quaternary mixture were confirmed by surface tension measurements, morphological observation, interaction energy calculation and the electrostatic potential analysis. The present results suggested that the amine/acid/AOS/LAPB mixture may be of use in relieving liquid loading of gas wells.

Evaluation of Slag Foaming Behavior Using Renewable Carbon Sources in Electric Arc Furnace-Based Steel Production

The influence of different carbon sources, including anthracite, calcined petroleum coke, three samples of high-temperature coke, biochar, and a mixture of 50 wt.% biochar and 50 wt.% coke, on slag foaming behavior was studied. The slag’s composition was set to FeO-CaO-Al2O3-MgO-SiO2, and the temperature for slag foaming was 1600 °C. The effect of the carbon sources was evaluated using foaming characteristics (foam height, foam volume, relative foaming height, and gas fraction), X-ray diffraction (XRD), chemical analysis of the slag foams, Mossbauer spectroscopy, observation by scanning electron microscope (SEM), and energy-dispersive spectroscopy (EDS) mapping. Different foaming phenomena were found among conventional sources, biochar as a single source, and the mixture of coke and biochar. Biochar showed the most inferior foaming characteristics compared to the other studied carbon sources. Nevertheless, the slag foaming process was improved and showed slag foaming characteristics similar to results obtained using conventional carbon sources when the mixture of 50 wt.% coke and 50 wt.% biochar was used. The XRD analysis revealed a difference between the top and bottom of the slag foams. In almost all cases, a maghemite crystalline phase was detected at the top of the slag foams, indicating oxidation; metallic iron was found at the bottom. Furthermore, a difference in the slag foam (mixture of coke and biochar) was found in the presence of such crystalline phases as magnesium iron oxide (Fe2MgO4) and magnetite (Mg0.4Fe2.96O4). Notwithstanding the carbon source applied, a layer between the foam slag and the crucible wall was found in many samples. Based on the SEM/EDS and XRD results, it was assumed this layer consists of gehlenite (Ca2(Al(AlSi)O7) and two spinels: magnesium aluminate (MgAl2O4) and magnesium iron oxide (Fe2MgO4).