Wanhua Chemical — TDI (2021) — Brine Chiller
By Qiangbin Chu · Sales Manager & Operations Lead
Wanhua Chemical Group Co., Ltd. is one of the world's largest producers of isocyanates. The TDI (toluene diisocyanate) manufacturing process involves highly exothermic phosgenation reactions that require reliable, high-capacity brine cooling to maintain safe operating temperatures and consistent product quality.
| Client | Wanhua Chemical — TDI (2021) |
| EPC / Design Institute | Hualu Engineering & Technology Co., Ltd. |
| Equipment | Brine Chiller × 3 sets |
| Design Code | GB |
| Cooling Capacity | 2,400 kW per unit |
| Motor Power | 900 kW |
| Refrigerant | R507 |
| Coolant | Ethylene glycol |
Customer Background
Wanhua Chemical Group Co., Ltd. is one of the world’s largest producers of isocyanates. The TDI (toluene diisocyanate) manufacturing process involves highly exothermic phosgenation reactions that require reliable, high-capacity brine cooling to maintain safe operating temperatures and consistent product quality.
Challenges and Engineering Requirements
Process Temperature Control in petrochemical processing
Wanhua Chemical required precise low-temperature cooling for Brine Chiller × 3 sets service in the petrochemical processing sector. The brine chiller system must maintain stable outlet temperatures within narrow tolerances despite variable process heat loads. Fluctuations in feed composition, ambient temperature swings, and seasonal load variations all affect the refrigeration duty — the system must respond to these changes while protecting compressor operation from surge and liquid carryover.
Refrigerant Selection and Safety
The choice of R507 reflects the balance between thermodynamic efficiency at the target evaporating temperature, compatibility with the plant’s existing refrigerant infrastructure, and safety classification under the applicable code. Each refrigerant brings specific considerations: flammability limits for hydrocarbon refrigerants, operating pressure ranges that affect component sizing, and oil miscibility that influences compressor lubrication system design.
Integration with EPC Engineering
The chiller packages were specified and documented by Hualu Engineering & Technology Co., Ltd. as part of a larger process unit. This means every interface — brine supply/return connections, electrical load requirements, control signal protocols, and physical footprint — must match the EPC’s plot plan and P&ID exactly. Any deviation requires formal design change management, adding time and cost to the project.
Why Wanhua Chemical Selected Lmart
Integrated refrigeration package capability. Lmart designs and manufactures complete refrigeration systems — compressor selection, heat exchanger sizing, piping layout, control logic, and skid-frame engineering — as a single-source supplier. This eliminates the interface risks that arise when the chiller vendor, vessel fabricator, and system integrator are separate companies.
Process refrigerant experience. Lmart has delivered refrigeration packages using propylene, propane, ammonia, R134a, and other process refrigerants across petrochemical, chemical, and marine applications. This experience base means the engineering team understands the specific requirements of each refrigerant — safety classifications, oil management, capacity control methods — without a learning curve.
Repeat performance. Lmart has delivered equipment to Wanhua Chemical and similar clients in the petrochemical processing sector, demonstrating consistent quality and on-time delivery performance across multiple projects.
Equipment & Scope of Supply
Lmart supplied three (3) brine chiller packages, each rated at 2,400 kW cooling capacity — a combined duty of 7,200 kW for the TDI facility. The systems use R507 refrigerant to chill an ethylene glycol secondary loop serving reactor jackets and process heat exchangers. Each compressor is driven by a 900 kW motor, and all units were designed and fabricated to GB standards.
Engineering was performed by Hualu Engineering & Technology Co., Ltd., Lmart’s long-standing partner on Wanhua’s isocyanate and specialty-chemical projects.
Quality Control and Project Execution
All equipment was manufactured under Lmart’s ISO 9001-certified quality management system with the following key inspection milestones:
- Material verification: Incoming inspection of all plates, forgings, and fittings against mill certificates; PMI spot checks on alloy materials
- Welding quality: All welding performed by qualified welders using approved WPS/PQR; NDE per GB requirements including RT/UT on pressure-retaining welds
- Dimensional inspection: In-process dimensional checks at shell rolling, head forming, and final assembly stages
- Pressure testing: Hydrostatic test to GB requirements, witnessed by the authorized inspector and/or client representative
- Documentation package: Complete data book including material certificates, weld maps, NDE reports, dimensional records, and test certificates
Equipment was delivered to Wanhua Chemical’s project site in China, meeting the project schedule requirements.
Results and Business Impact
Lmart successfully delivered 3 units of Brine Chiller × 3 sets to Wanhua Chemical, meeting the project’s quality, schedule, and documentation requirements. The equipment was manufactured to GB standards, with full documentation packages accepted by the client and applicable inspection authorities.
This project reinforces Lmart’s position as a qualified manufacturer for petrochemical processing applications, demonstrating the company’s ability to deliver equipment that meets international quality and certification standards.
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Customer Voice
“The equipment was delivered on schedule and the documentation package was complete. The quality of fabrication met our inspection requirements.”
— Wanhua Chemical project team (paraphrased from project review)
Note: Lmart respects client confidentiality. Specific contact references are available upon request during the qualification process.