Expanding and Optimizing Existing LNG Plants

Expanding and Optimizing Existing LNG Plants

Aug 18, 2015 | Automation, LNG, Optimization

The last several years have seen rapid changes in the U.S. and global LNG markets. Changes in production, demand, and pricing have affected operators’ plans for new builds, upgrades, and expansions. One of the most talked about changes in the LNG industry has been the glut of U.S.-produced LNG and the shift from importing to exporting it. The end result: several LNG gasification terminals have been converted into liquefaction terminals, with brownfield modification being much more cost effective.

But these complete conversions at LNG terminals represent only a small portion of expansions and optimizations of existing liquefaction plants. Despite recent price uncertainty in the LNG market, numerous companies like Cameron LNG, Cheniere, Freeport, and Kinder Morgan are still moving forward with plans to expand capacity at existing LNG plants, anticipating an increase in exports. In April, Moody’s estimated the cost of expanding U.S. LNG liquefaction capacity via brownfield modifications at roughly $800 per ton of capacity versus much higher greenfield development costs (the global average was roughly $1,500 per ton [PDF] at the end of 2014). Most of these expansions involve taking existing infrastructure and integrating new LNG trains to expand total production.

Expansion isn’t the only way to upgrade, however. Operators of LNG plants can turn to more subtle brownfield modifications to reduce energy costs and maximize feed rates. The mix of refrigerants used in the cooling process of many LNG plants can be optimized using modeling software to increase energy efficiency. Another way an LNG plant can become more efficient is through the addition or upgrade of process control systems. These types of systems are capable of taking constraints in an LNG plant’s processes and matching them up to more efficient ways to meet process objectives. Additional automation technologies can also be implemented in specific sections of the plant. The feed point, for example, can be a prime target for optimizing gas-to-LNG conversion (i.e. debottlenecking). Other areas that can be optimized with upgrades and automation add-ons include compressor controls, corrosion monitoring, burner management, and inventory management.