Liquefaction Processes

Kryopak has spent decades refining and improving the methods with which small, medium and now micro scale LNG facilities are designed and manufactured.

Each facility is a unique design that has been thoroughly optimized using sophisticated process models and computer aided 3D design to facilitate the most efficient design possible.

The selection of a particular gas liquefaction process is driven by customer requirements, plant capacity, and the availability of resources.

EXP

The patented Kryopak EXP process utilizes a turbo expander to “make” the required refrigerant for liquefaction using the inlet gas. This process can be configured as a single or dual turbo expander design that can be driven by electric motor or gas engine as required.

This simple system has very few components operating at cryogenic temperatures, when compared to alternative methods for creating LNG, resulting in a facility that is less complicated complex to own and operate.

The process is less efficient when compared to a mixed refrigerant cycle, using 15% more power to create the final LNG product.

Customers who have access to inexpensive source gas can leverage this design to its full potential, still others can benefit from the simplicity of the system.

SCMR

The single cycle mixed-refrigerant liquefaction process is a well tested, proven, and extensively implemented method for creating liquid natural gas.

This process is well suited to large base load LNG facilities, but can also be effectively utilized in the design of small and medium scale plants.

The mixed-refrigerant (MR) solution is blended and optimized for each unique design using a mixture of pure hydrocarbon components. The MR “cocktail” is compressed in a multi-stage compressor unit to a high operating pressure, which is then let down to a lower pressure across a control valve to produce the required refrigeration to liquefy the natural gas stream.

The MR mixture is comprised of Methane, Ethane, i-Butane, n-Butane, and Nitrogen mixed from 99.95% pure components at varying concentrations.

The availability of the MR components listed above can influence the decision to use a mixed-refrigerant design, as cost and availability vary with location.

PCMR

The pre-cooled mixed refrigerant cycle (PCMR) uses a closed loop ammonia or propane refrigeration circuit to pre-cool the natural gas stream during the liquefaction process.

The balance of the liquefaction process uses a mixed refrigerant (MR) “cocktail” to liquefy the natural gas stream. The MR mixture is comprised of Methane, Ethane, i-Butane, n-Butane, and Nitrogen mixed from 99.95% pure components at varying concentrations.

This pre-cooled process results in a more efficient plant design when compared to a traditional single cycle mixed refrigerant system (SCMR). The PCMR process uses approximately 3% less power than an SCMR system.

The availability of the MR components listed above can influence the decision to use a mixed-refrigerant design, as cost and availability vary with location.

Processes

E-Cascade

Kryopak has once again released a technique that sets itself apart from the competition in terms of portability and capability with the enhanced cascade cycle, or E-Cascade. This patent pending approach to natural gas liquefaction uses a variant on the traditional propane refrigeration cascade loop to increase plant performance and capacity.

The liquefaction portion of the plant uses a combination of propane and ethylene pre-cooling to reduce power requirements while increasing overall facility capacity.

This design has been optimized for the Micro LNG niche of 50 metric tons per day capacity and provides a compact and transportable design.