The Optimized Cascade Process is one of the most extensively used process in major Liquefaction plants worldwide. From Sabine Pass Louisiana to Queensland's LNG plants in Australia, the Optimized Cascade Process has been used for over four decades. This technology is based on three multi staged , cascading circuits using pure refrigerants (Propane, Ethylene and Methane). Other key features include use of Brazed Aluminium Heat Exchangers and insulated Cold Box Modules. Heat Integration in the process has been modified such that it approaches Natural gas and Refrigerant cooling curves which results in high efficiency. The use of Brazed Aluminium Heat Exchangers and Cold Box Modules allows for efficient heat transfer which can serve a wide range of LNG plant sizes. Depending on the Feed Gas characteristics a HRU and NRU option can be integrated in the process to further optimize the plant performance. The table below shows a list of current and under construction LNG plants that would be using the Optimized Cascade Process for liquefaction of natural gas.