Sponge Iron Plant (DRI Plant) – Complete Direct Reduced Iron Production Line with Rotary Kiln
What Is a Sponge Iron Plant / DRI Plant?
Sponge iron, also known as direct reduced iron (DRI), is a metallic iron product produced through a “direct reduction” process without melting iron ore. Because the reduced iron has a large number of micropores inside, it looks like a “sponge”, hence the name sponge iron.
The sponge iron plant is an industrial system that efficiently converts iron ore into a high-purity iron source that can “replace scrap steel.” It is an important source of raw materials for modern electric arc furnace steelmaking.
In the DRI (direct reduced iron) production process, iron ore lumps, pellets, or fine powder are heated to 900-1100°C and subjected to a strong reducing atmosphere to remove oxygen from the iron ore, thereby generating porous metallic iron. Mainstream processes include:
Coal-based DRI rotary kiln process: uses non-coking coal as a reducing agent.
Gas-based DRI rotary shaft furnace process: uses reducing gas (mainly H₂ and CO) produced from natural gas.
The Smarter DRI Choice
Why Choose Rotary Kiln DRI Process?
80% of DRI plants worldwide use rotary kiln technology
Can use low-grade iron ore and low-cost coal
Mature technology and stable output
Construction costs are far lower than gas-based shaft furnaces
Simple operation and easy maintenance
DRI Plant Production Process and Core Equipment
1. Raw Ore Preparation
Equipment: Crusher, Vibrating Screen, Impurity Removal Equipment
→ Iron ore is crushed, screened, and impurities removed to achieve a suitable particle size and specifications.
2. Raw Material Proportioning & Feeding
Equipment: Automatic batching system, belt scale, feed hopper, feeding device
→ Iron ore, non-coking coal, and limestone are metered according to proportions and stably conveyed to the head of the rotary kiln.
3. Direct Reduction in Rotary Kiln
Equipment: Sponge iron rotary kiln, preheater, burner, precision temperature control system
→ The raw material moves slowly in a rotary kiln at 900–1100°C, undergoing a direct reduction reaction with CO and H₂ produced by coal pyrolysis to form sponge iron.
4. Product Cooling
Equipment: Rotary cooler, water spray cooling system, or quenching cooler
→ The high-temperature sponge iron enters the cooling section and is rapidly reduced to a safe temperature to prevent secondary oxidation.
5. Magnetic Separation
Equipment: Magnetic separator, vibrating feeder, conveyor
→ Separates sponge iron from unreacted residue and carbon ash to obtain DRI with a high metallization rate.
6. Final Sponge Iron Product
Equipment: Conveying system, silos, finished product storage system
→ Qualified sponge iron is transported to the finished product area and can be used in EAF and IF steelmaking, or sold directly.
Direct Reduced Iron Project Delivery & EPC Service
Building a complete DRI (direct reduced iron) sponge iron plant requires not only the rotary kiln itself, but also comprehensive engineering capabilities and a systematic solution.
As a professional supplier of sponge iron plants and rotary kilns, we provide one-stop EPC turnkey services (engineering, procurement, and construction) to ensure safe, on-time commissioning and stable production.
Our DRI plant EPC services include:
01.
Process design and technical consultation
02.
Equipment manufacturing and quality control
03.
On-site installation and commissioning
04.
Operational training and skills transfer
05.
Spare parts supply and after-sales service
Sponge Iron Plant Specifications
Capacity: 50–600 TPD (Common Scale)
Rotary Kiln Dimensions: Φ1.9–4.8 m × 25–80 m
Fuel Type: Coal-Based
Metallization Rate: 85–90%
| Raw Material | Iron ore fines & lump ore, non-coking coal, dolomite / limestone |
| Product | Sponge Iron (DRI), Metallization 85–92% |
| Kiln Slope | 2.0–3.5% |
| Kiln Speed | 0.3–1.2 rpm (variable frequency) |
| Operating Temperature | 900–1100°C |
| Cooler Length | 20–35 m (matched to plant capacity) |
| Burner Heat Capacity | 4–12 MW (coal / natural gas, depending on kiln size) |
| Power Consumption | 65–95 kWh / ton DRI |
| Thermal Consumption | 1.1–1.5 Gcal / ton DRI |
| Water Consumption | 0.2–0.5 m³ / ton DRI |
| Dust Emission | ≤ 50 mg/Nm³ (with bag filter / multi-stage dust control) |
| System Control | PLC-based control with automatic temperature regulation |
| Area Requirement | 25,000–60,000 m² (depending on capacity) |
| Manpower | 50–120 persons (varies with automation & scale) |
| Design Life | 20+ years (with regular maintenance) |
Note: Typical ranges are industry-standard values. Exact specifications are customized based on ore quality, fuel type and project requirements.