EVALUATION OF AN ENERGY SUPPLY SYSTEM WITH AIR SEPARATION

摘要

A high performance energy supply system (HiPESS) by use of liquefied natural gas (LNG) is proposed, which is one of the promising electric energy supply systems to accomplish less pollutant emissions in the exhaust. By using methane as the fuel and high purity oxygen as the oxidizer, neither NOx nor SOx are ideally generated. In addition, to control the combustion temperature, carbon dioxide is recycled from the flue gas as the dilution gas. As the exhausted gas consists of only carbon dioxide and water, it is easy to separate, isolate, and treat carbon dioxide. To produce high purity oxygen economically, a cryogenic air separation system is applied by introducing the cold energy of LNG and modifying the conventional process. The electric power consumption is potentially reduced by 66%, compared with the conventional system. By installing the air separation system, the efficiency of HiPESS is also lowered by around 10% (if compared with a conventional power plant). However, this is not necessarily negative because HiPESS will make a great contribution towards preservation of the global environment.