Huayi Guangxi — Propane BOG (2021) — 630 kW Boil-Off Gas Compression Package for Propane Tank Area

Huayi (Guangxi) operates a petrochemical complex in Guangxi Province that includes large-scale refrigerated propane storage serving as feed for PDH (propane dehydrogenation) or steam cracking operations. Refrigerated propane is stored at atmospheric pressure near its boiling point (−42 °C), which minimizes storage tank pressure ratings but introduces a continuous boil-off gas management challenge.

Customer	Huayi (Guangxi)
Plant / Unit	Propane Tank Area — BOG Recovery
Equipment	Propane BOG Compressor Package
Design Institute	Wuhuan Engineering Co., Ltd.
Design Code	GB
Motor Power	630 kW per unit
Gas Handled	Propane BOG (Boil-Off Gas)
Application	BOG compression and recovery in propane tank farm
Quantity	3 sets

Customer Background

Huayi (Guangxi) operates a petrochemical complex in Guangxi Province that includes large-scale refrigerated propane storage serving as feed for PDH (propane dehydrogenation) or steam cracking operations. Refrigerated propane is stored at atmospheric pressure near its boiling point (−42 °C), which minimizes storage tank pressure ratings but introduces a continuous boil-off gas management challenge.

Ambient heat transfer through tank walls, roof, and piping connections continuously vaporizes a small fraction of the stored propane. This boil-off gas (BOG) must be removed to prevent tank overpressure. Without BOG recovery, the gas would be routed to flare — wasting valuable petrochemical feedstock (propane prices typically $400–600/Mt) and increasing the facility’s carbon emissions. BOG compressors capture this vapor, compress it, and return it to the process chain, maintaining both tank pressure within safe operating limits and overall facility efficiency.

Challenges and Engineering Requirements

System Integration and Package Design

Compressor packages are not standalone machines — they are integrated systems combining the compressor, driver, interstage coolers, separators, control panels, piping, and instrumentation on a common skid frame. Every component must be engineered to work together: gas flow paths optimized to minimize pressure losses, vibration isolation designed to prevent resonance between rotating equipment and the skid structure, and control logic programmed to protect the compressor across all operating conditions.

Process Gas Compatibility

Compressing Propane BOG Compressor Package service in the process industry sector requires materials and seal systems compatible with the specific gas composition, including trace contaminants that can cause accelerated corrosion, elastomer degradation, or lubricant breakdown. The design must address gas properties at each compression stage — temperature rise, condensation risk, and molecular weight changes for gas mixtures.

Noise, Vibration, and Mechanical Integrity

Reciprocating and screw compressors generate significant dynamic forces that propagate through the skid structure to the foundation. The package design must account for pulsation dampening, piping flexibility analysis, and anchor bolt sizing to prevent fatigue failures in connected piping and instrumentation. Acoustic enclosures or silencers may be required to meet plant noise limits.

Why Huayi Selected Lmart

Turnkey package engineering. Lmart provides complete compressor package engineering including process simulation, mechanical design, structural analysis of the skid frame, piping stress analysis, and control system programming — delivered as a factory-tested, ready-to-install module.

Multi-gas experience. Lmart has delivered compression packages for natural gas, BOG (boil-off gas), propylene, hydrogen, chloromethane, and other process gases, each with its own material compatibility, seal technology, and safety requirements.

Workshop integration and testing. Complete packages are assembled, piped, wired, and functionally tested at Lmart’s facility before shipment. Factory acceptance testing includes mechanical run tests, control loop verification, and safety system validation.

Engineering and Manufacturing Solution

Lmart engineered and fabricated Propane BOG Compressor Package for Huayi 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

All three packages were manufactured, factory-tested at Lmart’s facility, and delivered to the Guangxi site on schedule. The units were commissioned as part of the propane tank farm’s initial startup sequence, with performance verification confirming design BOG recovery rates under both steady-state and transient loading conditions.

Results and Business Impact

Lmart successfully delivered Propane BOG Compressor Package to Huayi, 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 process industry 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.”

— Huayi project team (paraphrased from project review)

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