Henan Hongke Heavy Machinery Co., Ltd. has delivered a Φ 2.5×45m rotary kiln system for soil remediation to a customer in Xiangtan, Hunan Province, China. The line uses thermal desorption technology to treat soil contaminated with organic pollutants (oils, pesticides, PCBs) and heavy metals. This is a brand-new installation—not a refurbishment, not an upgrade of old equipment.
Below is the full project breakdown: who the customer is, what problem they had, what we built, when it was delivered, and what the results were.
1. Customer Background
Location: Xiangtan, Hunan Province, China
Industry: Contaminated soil remediation / environmental services
Xiangtan is an industrial city in central Hunan with a history of chemical manufacturing, metallurgy, and machinery production. Decades of industrial activity have left a legacy of contaminated sites—soil impacted by oils, pesticides, chlorinated organics, and heavy metals. Local environmental service companies are now working to remediate these sites for redevelopment.
Our customer is a soil remediation contractor operating in this region. They take on projects for industrial site cleanup, brownfield redevelopment, and agricultural land restoration. Their work requires mobile or semi-mobile thermal treatment capacity that can handle variable soil conditions.
2. The Original Problem
Before approaching Henan Hongke Machinery, the customer faced several practical constraints:
| Problem | Impact |
|---|---|
| Variable contaminant types | Soil from different sites contained different pollutants—oils, pesticides, PCBs, heavy metals |
| Inconsistent treatment results | Older equipment could not maintain stable temperature profiles for different contaminants |
| Throughput limitations | Project deadlines required higher processing rates |
| Off-gas treatment gaps | Organic vapors and dust required more effective capture |
| Downtime for maintenance | Sticky or abrasive soils caused frequent stoppages |
| Regulatory pressure | Treated soil had to meet strict residual contaminant limits |
The customer needed a new, purpose-built thermal desorption system—not a modified dryer or a repurposed kiln. Their goal: consistent treatment results across different soil types, reliable continuous operation, and full compliance with environmental standards.
3. Why the Customer Chose Henan Hongke Machinery
After evaluating several suppliers, the customer selected us for specific, practical reasons:
a) Understanding of thermal desorption, not just rotary kiln supply
Thermal desorption depends on the interaction of soil feed properties, heating rate, residence time, desorption temperature, and off-gas handling. We discussed these parameters in detail during technical exchange—not just dimensions and price.
b) Custom design for variable soil conditions
The customer's feed was not a single, uniform material. It was soil from different sites with different moisture, organic content, and contaminant profiles. Our engineering team designed the kiln and control system to handle this variability.
c) Complete line responsibility
We supplied the full scope: feed preparation, the rotary kiln, heating system, discharge cooling, off-gas treatment (cyclone + bag filter + optional afterburner), and PLC controls. The customer did not have to coordinate multiple suppliers.
d) Brand-new equipment
The customer explicitly wanted a new system built for this application—not refurbished equipment and not a repurposed cement or dryer unit.
e) Factory inspection and reference review
The customer reviewed our manufacturing facility and similar thermal processing projects before signing.
4. Equipment Configuration
The delivered line is built around a Φ 2.5×45m rotary kiln.
| Parameter | Specification |
|---|---|
| Kiln diameter | 2.5 m |
| Kiln length | 45 m |
| Application | Thermal desorption of contaminated soil |
| Target contaminants | Oils, pesticides, PCBs, volatile organics, heavy metals |
| Kiln slope | 3–4% |
| Rotation speed | Variable frequency drive |
| Operating temperature | Adjustable by contaminant type (typically 200–600°C for organics; higher for some applications) |
| Drive system | Heavy-duty gear drive with main and auxiliary motors |
| Sealing | Labyrinth seals with air purge at head and tail |
| Atmosphere | Controlled—direct or indirect heating configuration |
Scope of supply:
| System | Function |
|---|---|
| Feed preparation | Soil crushing, screening, moisture adjustment |
| Φ 2.5×45m rotary kiln | Thermal desorption of contaminants |
| Heating system | Hot gas generator (gas, oil, or coal) with temperature control |
| Discharge cooling | Cooling of treated soil for safe handling |
| Cyclone separator | Primary dust removal |
| Bag filter | Fine particulate capture |
| Afterburner (optional) | Destruction of organic vapors |
| PLC control system | Temperature, feed rate, speed, and emission monitoring |
5. Delivery Timeline
| Stage | Status |
|---|---|
| Technical exchange and process design | Completed |
| Manufacturing at Henan Hongke facility | Completed |
| Factory assembly and no-load testing | Completed |
| Shipment to Xiangtan, Hunan | Completed |
| On-site installation | Completed |
| Commissioning and hot testing | Completed |
| Handover to customer | Completed |
The line has been delivered and handed over to the customer's operations team.
6. Commissioning Results
| Performance Metric | Result |
|---|---|
| Desorption temperature control | Stable across operating range |
| Treatment consistency | Consistent results across different soil batches |
| Throughput | Meets agreed design capacity |
| Residual contaminant levels | Treated soil meets project specifications |
| Off-gas treatment | Dust and organic vapors captured effectively |
| Operational stability | Continuous operation achieved |
| Emissions | Within regulatory limits |
7. Customer Feedback
"The kiln handles different soil types without the problems we had before. Temperature control is stable, and the treated soil meets our project requirements. The engineering team was responsive during installation and commissioning. We're satisfied with the equipment and the support." — Project Manager, Xiangtan soil remediation contractor
8. What This Means for the Customer
| Benefit | Practical Value |
|---|---|
| Handles variable contaminants | One system for oils, pesticides, PCBs, heavy metals |
| Consistent treatment results | Treated soil meets regulatory limits |
| Higher throughput | Meets project deadlines |
| Effective off-gas treatment | Environmental compliance |
| Reliable operation | Less downtime, lower maintenance costs |
| Full-scope supplier | Single point of responsibility |
9. Building Long-Term Partnerships
Our commitment to the Xiangtan customer does not end at handover. We continue to provide:
Technical support on process optimization for different soil types
Spare parts availability for critical components
Maintenance guidance and preventive maintenance planning
Support for future capacity expansion or process adjustment
We view this delivery as the start of a long-term working relationship, not a one-time transaction.
About Henan Hongke Heavy Machinery Co., Ltd.
Henan Hongke Heavy Machinery Co., Ltd. (Henan Hongke Machinery) has been designing and manufacturing industrial processing equipment since 2006. Our product portfolio includes:
Rotary Kilns – for soil remediation, zinc oxide, lime, dolomite, metallurgy, and mineral calcination
Rotary Dryers – for sludge, sand, gypsum, biomass, and industrial materials
Ball Mills – for ore, slag, cement, and chemical grinding
Crushers – for primary and secondary size reduction
We focus on one-stop solutions for mining and materials processing—complete systems, not just individual machines. From engineering to installation and after-sales service, we stay with our customers every step of the way.
Let's Talk About Your Soil Remediation Project
If you are treating soil contaminated with oils, pesticides, PCBs, or heavy metals, we can discuss kiln sizing, thermal desorption parameters, and off-gas treatment based on your actual soil data.
Contact Henan Hongke Heavy Machinery Co., Ltd. — we will review your material data and propose a configuration that fits your remediation targets.
Henan Hongke Heavy Machinery Co., Ltd.
Rotary Kilns | Rotary Dryers | Ball Mills | Crushers – Built for Reliability, Backed by Service