Zhejiang Petrochemical — EO/EG (2019) — 380 kW Brine Chiller for Ethylene Oxide / Ethylene Glycol Production

Zhejiang Petroleum & Chemical's Zhoushan complex includes an EO/EG production unit that converts ethylene to ethylene oxide (EO) via silver-catalyzed partial oxidation, then hydrates EO to produce mono-ethylene glycol (MEG) — a primary feedstock for polyester fibers, PET resin, and antifreeze formulations. China is the world's largest MEG consumer, and integrated complexes like Zhoushan produce EO/EG as part of a vertically integrated ethylene value chain.

Customer	Zhejiang Petroleum & Chemical Co., Ltd.
Plant / Unit	EO/EG (Ethylene Oxide / Ethylene Glycol)
Equipment	Brine Chiller Package
Design Institute	CNPC Northeast Refining & Chemical Engineering Co., Ltd.
Design Code	GB
Cooling Capacity	380 kW per unit
Motor Power	185 kW
Refrigerant	R1270 (Propylene)
Coolant	Ethylene glycol
Quantity	2 sets

Customer Background

Zhejiang Petroleum & Chemical’s Zhoushan complex includes an EO/EG production unit that converts ethylene to ethylene oxide (EO) via silver-catalyzed partial oxidation, then hydrates EO to produce mono-ethylene glycol (MEG) — a primary feedstock for polyester fibers, PET resin, and antifreeze formulations. China is the world’s largest MEG consumer, and integrated complexes like Zhoushan produce EO/EG as part of a vertically integrated ethylene value chain.

The EO production step is highly exothermic and thermally sensitive. Reactor temperatures must be controlled within a narrow window to prevent catalyst deactivation and avoid the risk of ethylene oxide decomposition, which is explosive above certain concentrations and temperatures. Downstream, the EO absorber column requires chilled lean glycol to scrub EO from the reactor effluent gas, and the glycol dehydration section requires precise temperature staging for product grade control.

Challenges and Engineering Requirements

Process Temperature Control in petrochemical processing

Zhejiang Petroleum & Chemical Co., Ltd. required precise low-temperature cooling for Brine Chiller 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 CNPC Northeast Refining & Chemical Engineering 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 Zhejiang Petroleum & Chemical Co., Ltd. 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 Zhejiang Petroleum & Chemical Co., Ltd. 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 Brine Chiller Package for Zhejiang Petroleum & Chemical Co., Ltd. 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.

Package Configuration and Quality

Each 380 kW brine chiller is delivered as a self-contained skid package comprising:

• Twin-screw compressor with slide valve capacity control (10–100% modulation range)
• Shell-and-tube evaporator (refrigerant side) and condenser
• Oil separator with automatic return system
• Electronic expansion valve for precise superheat control
• Control panel with PLC, HMI touchscreen, and DCS communication interface
• Safety instrumentation: high-pressure cutout, low-pressure cutout, oil differential pressure switch, motor overload protection, and R1270 gas leak detector

All pressure-containing components were fabricated and hydrostatic-tested per GB 150. Each complete package underwent factory performance testing at Lmart’s facility to verify cooling capacity, power consumption, and control response before shipment.

Results and Business Impact

Lmart successfully delivered Brine Chiller Package to Zhejiang Petroleum & Chemical Co., Ltd., 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.

Customer Voice

“The equipment was delivered on schedule and the documentation package was complete. The quality of fabrication met our inspection requirements.”

— Zhejiang Petroleum & Chemical Co., Ltd. project team (paraphrased from project review)

Note: Lmart respects client confidentiality. Specific contact references are available upon request during the qualification process.