Henan Hongke Heavy Machinery Co., Ltd. is pleased to report on the successful deployment of a 400-ton-per-day lime rotary kiln production line at a customer site in Yinchuan, Ningxia Hui Autonomous Region, China. This project demonstrates our capability to deliver large-scale, engineered lime calcination systems for the metallurgical and industrial markets.
Project Background: Meeting Ningxia's Industrial Demand
Ningxia has emerged as a significant industrial hub in northwestern China, with growing steel production, calcium carbide manufacturing, and coal chemical processing sectors . These industries share a common need: high-quality active lime (quicklime) for fluxing, chemical reactions, and environmental treatment.
Our customer, a major industrial operator in the Yinchuan area, identified a gap in the local lime supply chain. With existing kilns unable to meet the quality and volume requirements of downstream users, they turned to Henan Hongke Machinery for a complete rotary kiln solution.
The customer's requirements were clear:
| Requirement | Target |
|---|---|
| Daily capacity | 400 tons of active lime |
| Product quality | High reactivity (activity degree ≥ 340 ml), low residual CO₂ |
| Fuel flexibility | Pulverized coal or natural gas |
| Environmental compliance | Dust emissions below 30 mg/Nm³ |
| Operational reliability | 24/7 continuous operation with > 92% annual uptime |
Our Solution: Φ3.5×75m Rotary Kiln System
The heart of this production line is a Φ3.5m diameter by 75m long rotary kiln — a proven configuration for medium-to-large-scale lime production . Henan Hongke Heavy Machinery engineered the entire system with the following key components.
Rotary Kiln Specifications
| Parameter | Value |
|---|---|
| Diameter | 3.5 meters |
| Length | 75 meters |
| Capacity | 400 TPD active lime |
| Kiln inclination | 3.5–4% |
| Rotation speed | 0.5–3.5 rpm (variable frequency drive) |
| Operating temperature | Up to 1,250°C (burning zone) |
| Shell material | Q345R boiler-grade steel |
| Refractory lining | High-alumina brick + insulation layer |
Complete System Configuration
This project is a full production line — not just a kiln . Henan Hongke Heavy Machinery supplied the entire system including:
1. Vertical Preheater
Recovers waste heat from kiln exhaust gases, preheating limestone to approximately 900°C and completing 25–35% calcination before material enters the kiln. This reduces overall fuel consumption by up to 30% compared to systems without preheaters.
2. Φ3.5×75m Rotary Kiln
The core calcination unit where limestone (CaCO₃) is thermally decomposed into quicklime (CaO) and CO₂ at temperatures between 1,100°C and 1,250°C . The 75-meter length provides sufficient residence time for complete calcination.
3. Vertical Cooler
Rapidly cools the hot lime product from approximately 1,100°C to below 100°C, preserving high reactivity. The recovered hot air is recycled to the kiln as secondary combustion air, further improving thermal efficiency.
4. Multi-channel Burner
Provides precise flame control and fuel flexibility (coal powder, natural gas, or mixed fuels).
5. Dust Collection System
Multi-stage treatment including cyclone pre-separator and pulse-jet bag filter, achieving outlet dust concentrations consistently below 30 mg/Nm³ .
6. Automation & Control
DCS-based centralized control system monitoring temperature, pressure, material flow, and emissions in real time .
Project Status: Successful Commissioning
The 400 TPD lime rotary kiln project in Yinchuan has been successfully commissioned and is now in full operation. Key achievements include:
Full production capacity reached – The system consistently produces 400 tons of high-quality active lime per day
Product quality verified – Activity degree meets the ≥ 340 ml specification, suitable for metallurgical and chemical applications
Environmental compliance achieved – Dust emissions consistently below 30 mg/Nm³, meeting national standards
Fuel flexibility demonstrated – System operates effectively on both pulverized coal and natural gas
Operational reliability – The system is achieving > 92% annual uptime as designed
Customer Benefits
The successful operation of this 400 TPD lime production line delivers:
| Benefit | Impact |
|---|---|
| Consistent high-quality product | Active lime meeting metallurgical and chemical specifications |
| Lower operating costs | Preheater technology reduces fuel consumption by ~30% |
| Reliable 24/7 operation | Heavy-duty design and automation minimize downtime |
| Environmental compliance | Emissions controlled to meet national standards |
| Local supply chain | Reduces transportation costs and import dependency for the region |
About Henan Hongke Heavy Machinery Co., Ltd.
Henan Hongke Heavy Machinery Co., Ltd. (Henan Hongke Machinery) has been manufacturing industrial processing equipment since 2006. Our product portfolio includes:
Rotary Kilns – for lime, dolomite, cement, metallurgy, and mineral calcination
Rotary Dryers – for sludge, biomass, and industrial materials
Ball Mills – for ore, slag, cement, and chemical grinding
Crushers – for primary and secondary size reduction
We provide custom engineering, full manufacturing, installation guidance, commissioning support, and after-sales service for customers worldwide.
Summary
The 400 TPD lime rotary kiln project in Yinchuan, Ningxia, demonstrates Henan Hongke Heavy Machinery's ability to deliver large-scale, engineered lime calcination solutions that meet demanding industrial requirements. By integrating preheater technology, advanced sealing, automated controls, and a proven Φ3.5×75m kiln design, the system delivers consistent product quality with optimized fuel consumption and reliable 24/7 operation.
For lime calcination, mineral processing, or other thermal treatment applications, contact Henan Hongke Heavy Machinery Co., Ltd.
Henan Hongke Heavy Machinery Co., Ltd.
Rotary Kilns | Rotary Dryers | Ball Mills | Crushers – Engineered for Real-World Results