A NOVEL PROCESS SYSTEM FOR RECOVERING ENERGY, WATER AND NITROGEN RESOURCES FROM EXHAUST FLUE GASES
Abstract - The present invention describes a novel process system for recovering energy, water and nitrogen resources from the exhaust flue gases of existing internal combustion equipment. This is invention is already filed with the US Patent office in the beginning of 2023. The system is designed to operate at various temperature ranges of the hot flue gases and is capable of recovering useful power, water and nitrogen resources from Combustion Gas Turbines (CGTs), residual flue gas from Heat Recovery Steam Generators (HRSG), steam boilers, reboilers, furnaces, fire heaters and other equipment.
The invented system establishes a Special Organic Rankine Cycle (SORC) with multi-stages of refrigerant evaporator heat exchangers and two stages of condenser coolers to manage the flue gas temperatures effectively for heat energy extraction and water recovery optimization. The system employs a carefully selected refrigerant, R-717 (ammonia), which is thermodynamically stable and efficient at the operating temperature ranges.
The process system also involves integrating equipment to capture useful water and nitrogen resource that is present in the exhaust flue gases. This is achieved by using a special blower to slightly increase the pressure of the flue gas followed by gas compression, nitrogen separation/water content increase and then cooling below the water condensation temperature. The cooled flue gas is then flowed through a conduit into a knock-out vessel (vapour-liquid separator) to remove condensed water.
The system offers several advantages including the recovery of useful power, water and nitrogen resources from the exhaust flue gases, which would otherwise be wasted. The process system is also environmentally friendly as it reduces the release of greenhouse gases and lowers water usage. Furthermore, the system can be easily integrated into existing internal combustion equipment without significant modifications, making it cost-effective.
The present invention has significant potential for applications in a variety of industries, including power generation, chemical processing, and manufacturing, where internal combustion equipment is commonly used. The system offers a sustainable solution for recovering valuable resources from exhaust flue gases while reducing the environmental impact of such equipment.