Overview
Slag material is an industrial byproduct generated during the smelting of ores to extract metals like iron, copper, and lead. Primarily composed of silicates, oxides, and sulfides, it forms when flux materials react with impurities in molten metal. Modern slag valorization practices have transformed this waste product into a valuable resource for circular economies. Globally, over 400 million tons of slag are produced annually, with blast furnace slag (from iron production) and steel slag being the most commercially significant types. Its utilization reduces landfill waste and CO₂ emissions in construction applications compared to virgin materials.
Physical and Chemical Properties
Slag exhibits variable physical characteristics depending on its cooling method. Air-cooled slag forms crystalline structures with high density, while water-quenched granulated blast furnace slag (GBFS) becomes glassy and more reactive. Chemical composition typically includes 30-45% SiO₂, 30-45% CaO, and 5-15% Al₂O₃, with smaller amounts of MgO, FeO, and sulfur compounds. The material's hydraulic properties make it particularly valuable. When finely ground, GBFS reacts with water and activators (like cement) to form cementitious compounds. Steel slag often contains higher free lime content, requiring aging to prevent expansion issues in applications. Recent studies focus on optimizing slag chemistries for specific performance requirements in different industries.
Main Applications
In construction, slag serves as a sustainable alternative to natural aggregates. Ground granulated blast furnace slag (GGBFS) replaces 30-70% of Portland cement in concrete, enhancing durability and reducing thermal cracking. Its use lowers the carbon footprint by approximately 800 kg CO₂ per ton compared to traditional cement production. Steel slag aggregates improve asphalt skid resistance and are widely used in road bases. Agricultural applications leverage slag's calcium and magnesium content to neutralize acidic soils, while some specialized slags serve as phosphate fertilizers. Emerging uses include wastewater treatment (heavy metal adsorption) and geopolymer production, where its aluminosilicate content is activated by alkaline solutions to create low-carbon binders.
Safety and Storage
While generally stable, slag requires proper handling due to potential dust generation and alkaline pH (typically 8-12). Steel slag may contain leachable chromium compounds, necessitating EN 1744-1 compliance testing for construction use. Bulk storage should prevent moisture accumulation to maintain flowability and prevent caking. Workers should use NIOSH-approved N95 respirators when processing dry slag, along with eye protection and gloves. Most jurisdictions classify slag as non-hazardous waste, but transport documentation must specify the material type and processing method. Some countries require radioactivity testing due to natural radionuclide concentrations in raw materials.
B2B Procurement Guide
Industrial buyers should prioritize suppliers with ISO 9001-certified slag processing facilities. Key procurement considerations include consistent particle size distribution (especially for GGBFS requiring <45μm fineness), activity index (minimum 70-80% at 28 days), and low residual metal content. Regional availability significantly impacts logistics costs—steel plants typically sell slag within 300km radius. Contract terms should address quality consistency, with penalties for deviation from specified chemical composition. Large infrastructure projects may secure multi-year supply agreements with volume discounts. Testing protocols should include XRF analysis for major oxides and ASTM C989/C1866 performance tests for cementitious applications.
Related Manufacturers
- 主营：铁砂铁粉、滑石粉、硅藻土、炉渣、赤铁红、红土黄土、沸石粉、木粉、重钙、轻钙、磁粉、膨润土、锰砂、硅灰、活性白土、石英粉、萤石粉、重晶石粉、高岭土、莫来砂、珍珠岩粉、粉煤灰、白水泥、远红外粉
- 主营：五彩石、黑色鹅卵石、机制鹅卵石、炉渣、彩砂、陶瓷球、染色彩砂、造景彩砂、粉色彩纱、烧结彩砂、钢渣、黏土、夜光石、铁砂、玻璃砂
- 主营：硅砖、硅砂、硅粉、优质硅砖、熔融石英砖、零膨胀硅砖、玻璃窑硅砖、碳素炉硅砖
- 主营：轻质隔墙板、陶粒隔墙板、grc轻质隔墙板、砖胎膜用的材料批发、防火轻质隔墙板、基础砖胎模、砖胎膜预制板、砖胎膜、板胎膜、预制砖胎膜、承台砖胎模、砖胎模、砖胎膜预制板厂家、砖胎膜价格、内墙轻质隔墙板、空心轻质隔墙板、预制板胎膜、pc砖胎膜、预制胎膜板、集水井砖胎膜、筏板基础预制板、基坑承台预制板、基础承台模板、地下室承台、预制砖胎模
- 主营：核桃壳滤料、导电用云母粉、负离子液、高炉渣价格、贝壳粉
- 主营：炉渣铝粉磨粉机、破碎机、制砂机
- 主营：鹅卵石、雨花石、夜光石、垫层用炉渣供应、水洗石、彩色石子、火山岩、烘干砂、石英砂、金刚砂、彩砂、鹅卵石切片、蘑菇石、膨润土、面包石、高岭土、微硅粉、硅微粉、重钙粉、白云石粉、火山石粉、轻钙粉、滑石粉、硅酸铝粉、矿粉、粉煤灰
- 主营：贝壳粉、粘土球、水洗砂、炉渣、白沙子、玻璃砂、蛭石粉、珍珠岩、夜光石、重钙粉、矿物盐、玻璃粉、粘土粉、烘干河、氧化铁、高岭土、填充料、赤铁粉、325目赤、硅藻土、水洗沙、滑石粉、电气石、鹅卵石、石英砂、水磨石
- 主营：铁砂、铁粉、重钙、建筑保温隔热层材料、轻钙、氧化钙、白水泥、滑石粉、膨润土、红土黄土、硅灰、硅藻土、活性白土、萤石粉、石英粉、重晶石粉、高岭土、沸石粉、莫来砂、珍珠岩粉、膨润土猫砂、赤铁粉、粉煤灰、锰砂、石英砂
- 主营：重选设备、选矿摇床、螺旋溜槽、炉渣粉碎机、圆筒洗矿机、双轴洗矿机、轮斗洗沙机、圆盘给料机、螺旋洗沙机、槽式给料机、螺旋分级机、球磨分级一体机、摆式给料机、球磨机、细沙回收机、振动筛、跳汰机、振动洗金机、淘金设备、筛分设备、滚筒洗金机、矿用设备、全套洗金淘金设备、鼓动溜槽、震动筛洗金机、混汞摇床
- 主营：云母、高岭土、氧化铁颜料、白炭黑、火山石、绿沸石、陶瓷砂、麦饭石陶瓷球、海泡石、石墨、硅藻土、碳化稻壳、贝壳粉、玻璃砂玻璃砂、松树皮、有机覆盖物、蛭石、椰糠椰壳砖营养土、仿瓷颗粒砂、莫来砂、复合岩片贝壳彩片、电气石、玛瑙石珠、还原铁粉铁砂
- 主营：硫铝酸盐水泥、堵漏剂、铝酸盐水泥、高铝水泥、速凝剂、灌浆料、锚固剂、高铝浇注料、耐火水泥、堵漏王、道路修补料、耐酸水泥、水玻璃、树脂锚固剂、注浆料、速凝剂母料、液体速凝剂、高水注浆料、耐火浇注料、快硬硫铝酸盐水泥、低碱度硫铝酸盐水泥、52.5硫铝酸盐水泥、环氧树脂砂浆、耐酸胶泥
- 主营：榨油系列设备、烘干机系列设备、金属破碎机系列设备、炉渣粉碎机、砂石线系列设备、铜米机、制碳系列设备
- 主营：造景彩色沙、儿童沙画台、园林景观鹅卵石、石英砂、地坪砂、金刚砂、水洗石、重钙粉、蛭石、玻璃砂、石英粉、陶瓷砂、复合岩片、火山石、珍珠岩、钢渣
- 主营：ALC隔墙板、蒸压加气混凝土板、水泥空心板、炉渣空心板、轻集料多孔板、砖胎膜、预制承台膜板、GRC板、轻质隔墙板、蒸压砖、小青砖、聚苯颗粒轻质隔墙板、装配式墙板施工、空心隔墙板、蒸压加气混凝土条板、AAC隔墙板、NALC隔墙板、蒸压砂加气混凝土砌块、砂加气砌块、加气块、装配式墙板、蒸压加气混凝土板安装、水泥空心板施工、砂加气板材、轻质复合墙板