Sinopec Zhenhai — HDPE (2020) — 175 kW Direct Cooling System for High-Density Polyethylene
By Qiangbin Chu · Sales Manager & Operations Lead
Sinopec Zhenhai Refining & Chemical Company is one of China's largest integrated refining and petrochemical enterprises, located in the Zhenhai district of Ningbo, Zhejiang Province. With a refining capacity exceeding 23 Mt/a and integrated ethylene, propylene, and polyolefin production, Zhenhai is a flagship facility within the Sinopec system.
| Customer | Sinopec Zhenhai Refining & Chemical Company |
| Plant / Unit | HDPE (High-Density Polyethylene) |
| Equipment | Direct Cooling Compressor Package |
| Design Institute | SEI (Sinopec Engineering Incorporated) |
| Design Code | GB |
| Cooling Capacity | 175 kW |
| Motor Power | 132 kW |
| Refrigerant | R1270 (Propylene) |
| Quantity | 1 set |
Customer Background
Sinopec Zhenhai Refining & Chemical Company is one of China’s largest integrated refining and petrochemical enterprises, located in the Zhenhai district of Ningbo, Zhejiang Province. With a refining capacity exceeding 23 Mt/a and integrated ethylene, propylene, and polyolefin production, Zhenhai is a flagship facility within the Sinopec system.
The HDPE unit produces high-density polyethylene via slurry-loop or gas-phase reactor technology for applications in pressure pipe (PE100), blown film, and blow molding. HDPE production involves ethylene polymerization with chromium or Ziegler-Natta catalysts in the presence of hydrogen (for molecular weight control) and co-monomers (1-butene or 1-hexene for density control). The direct cooling package serves a specific process cooling duty within the HDPE production loop where eliminating the intermediate heat transfer fluid improves thermal efficiency at a targeted process point.
Challenges and Engineering Requirements
Process Temperature Control in petrochemical processing
Sinopec Zhenhai Refining & Chemical Company required precise low-temperature cooling for Direct Cooling Compressor Package 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 R1270 (Propylene) 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 SEI (Sinopec Engineering Incorporated) 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 Sinopec Zhenhai Refining & Chemical Company 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 Sinopec Zhenhai Refining & Chemical Company and similar clients in the petrochemical processing sector, demonstrating consistent quality and on-time delivery performance across multiple projects.
Engineering and Manufacturing Solution
Lmart engineered and fabricated Direct Cooling Compressor Package for Sinopec Zhenhai Refining & Chemical Company to GB. The scope of supply included complete detail design, material procurement, fabrication, inspection, testing, and documentation.
Key engineering considerations for this project included thermal-hydraulic performance optimization, material selection for the specific process environment, and compliance with GB requirements for design, fabrication, and inspection.
The equipment was manufactured at Lmart’s Zhangjiagang facility, which provides full-cycle fabrication capabilities including plate rolling, head forming, machining, welding (SAW, GTAW, SMAW), post-weld heat treatment, and NDE — all under a single quality management system.
Delivery and Outcome
The unit was delivered as a complete factory-assembled package to the Zhenhai site, commissioned, and integrated into the HDPE unit’s operation. This project marked Lmart’s first direct cooling delivery to Sinopec Zhenhai — a relationship that subsequently expanded to include acrylonitrile brine chillers (23,300 kW), PDH refrigeration systems (8,330 kW), solvent/BOG systems, and propylene-based brine chillers from 2022 onward. The progression from a single 175 kW unit to multi-MW systems within two years illustrates the value of establishing initial supply relationships with major end users through smaller, well-executed projects.
Results and Business Impact
Lmart successfully delivered Direct Cooling Compressor Package to Sinopec Zhenhai Refining & Chemical Company, 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.”
— Sinopec Zhenhai Refining & Chemical Company project team (paraphrased from project review)
Note: Lmart respects client confidentiality. Specific contact references are available upon request during the qualification process.