Lmart to Supply a Propylene Refrigeration Package for Rongsheng’s Jintang Cryogenic Ethylene Tank Farm

Summary

In July 2026, Suzhou Lmart Energy Equipment Co., Ltd. received an order from Rongsheng Petrochemical Co., Ltd. for a propylene refrigeration package serving the cryogenic ethylene tank farm at its Jintang new materials project.

One unit is supplied, delivered as a complete skid: compressor package integration, associated heat exchangers, lube oil system, prefabricated process piping, instrumentation and control panel.

Where the package sits in the tank farm

Ethylene boils below minus one hundred degrees Celsius at atmospheric pressure, so cryogenic ethylene is held in fully refrigerated atmospheric storage. However good the insulation, ambient heat continues to enter the tank. Liquid evaporates continuously, boil-off gas is generated, and tank pressure rises with it.

There are two ways to deal with that gas. Compress it and send it to flare or to a downstream network — simple, but it is product leaving the site. Or reliquefy it and return it to the tank, which calls for a refrigeration system able to condense the boil-off gas again.

The propylene refrigeration package serves as the warm stage of a cascade refrigeration system. Its duty condenses the refrigerant of the cold stage, and the cold stage then handles the ethylene temperature level. A single refrigeration stage does not comfortably span the temperature difference from ambient down to ethylene storage conditions, so a cascade arrangement is the usual approach.

For the tank farm, a refrigeration stop means tank pressure loses its means of control and safety is maintained by relief — which shows up directly as product loss. The refrigerant compressor package is therefore continuous-duty equipment.

Engineering requirements behind the selection

Continuous duty and tank pressure stability. The unit is designed for continuous tank farm operation. Running stability maps directly onto tank pressure control stability, and therefore onto flare volume.

Cascade stage matching. As the warm stage, the unit’s operating parameters are matched to the cold stage. Interstage heat exchange margin and duty split determine how the system behaves across the ambient temperature range.

Refrigerant purity and system cleanliness. With propylene as refrigerant, moisture, non-condensables and contaminants in the system affect cycle efficiency and equipment life. Cleanliness control during fabrication and the drying and purging steps before despatch are specified accordingly.

Low-temperature materials and insulation. Components in contact with the cold medium are selected for low-temperature toughness, and cold insulation is designed for the service conditions.

Hazardous area and tank farm interlocks. A tank farm is a gas hazardous area. Electrical protection level, pressure relief, emergency shutdown and the tank farm’s overall safety interlocks are engineered as one system.

Delivery milestones. Equipment arrival is tied to tank farm construction progress, and as-built documentation must satisfy the owner’s and the inspection authority’s filing requirements.

Lmart’s scope and execution

Package integration and skid prefabrication. Lmart carries out system integration and complete skid prefabrication for the propylene refrigeration package. Compressor and drive motor, heat exchangers, lube oil system, process piping, instrumentation and control panel are assembled, piped and wired in the workshop, and the package leaves the works as a finished skid. Lmart’s package integration is based on oil-flooded screw machines.

In-house heat exchangers and pressure equipment. Heat exchangers and pressure vessels in the package are manufactured in Lmart’s own workshops. Stainless steel and carbon steel are fabricated in separate workshops to prevent iron contamination of wetted surfaces on both the refrigerant and process sides.

Manufacturing and inspection. Welding follows qualified procedures. Welder qualification, NDE coverage, hydrostatic testing and third-party inspection are executed against the project inspection and test plan. System purging, drying and inerting are completed before despatch. Material certificates and inspection records are delivered with the package.

Not the first time — same Jintang project

Lmart previously supplied the ammonia refrigeration package for the ABS plant at the Jintang new materials project.

The propylene refrigeration package for the cryogenic ethylene tank farm is the second package on the same site. Same project, same owner, same site conditions, and the same supplier chosen a second time — that says what it says about how the first one has run.

What the order covers

For the owner, a tank farm refrigeration system pays back in product. Stable refrigeration means boil-off gas returns to the tank as liquid rather than leaving through the flare.

For Lmart, the order applies the company’s industrial refrigeration experience to cryogenic storage. Boil-off handling on ethylene, LNG and LPG tank farms is the same class of system problem, and this order builds an execution record in that direction.

Lmart provides commissioning attendance and spare parts support after delivery. Through the execution period, design, manufacturing, inspection and shipment milestones are coordinated with the owner and the inspection authority.