209results about "Heat recovery" patented technology

A method of and a power plant for generating power by combusting carbonaceous fuel with substantially pure oxygen, and a method of modifying a process of generating power by combusting carbonaceous fuel from combusting the fuel with air to combusting the fuel with substantially pure oxygen. The methods include feeding substantially pure oxygen into a furnace for combusting fuel with the oxygen to produce exhaust gas including mainly carbon dioxide and water, recovering low-grade heat from the exhaust gas by using multiple exhaust gas coolers arranged in a downstream portion of the exhaust gas channel, wherein a first portion of the recovered low-grade heat is used for preheating feedwater; pressurizing a first portion of the exhaust gas in multiple exhaust gas compressors so as to produce liquid carbon dioxide, recycling a second portion of the exhaust gas to the furnace via an exhaust gas recycling channel, using a first portion of steam extracted from a steam turbine system to preheat feedwater, wherein the first portion of the recovered low-grade heat is more than 50% of the total amount of recovered low-grade heat, or larger than the first portion of the recovered low-grade heat in the air-fired process, allowing minimizing of the first portion of the extracted steam, and the expanding of a second portion of the extracted steam in at least one auxiliary steam turbine for driving at least one compressor or at least one pump of the power plant.

A method of reducing pollutants exhausted into the atmosphere from the combustion of fossil fuels. The disclosed process removes nitrogen from air for combustion, separates the solid combustion products from the gases and vapors and can capture the entire vapor / gas stream for sequestration leaving near-zero emissions. The invention produces up to three captured material streams. The first stream is contaminant-laden water containing SOx, residual NOx particulates and particulate-bound Hg and other trace contaminants. The second stream can be a low-volume flue gas stream containing N2 and O2 if CO2 purification is needed. The final product stream is a mixture comprising predominantly CO2 with smaller amounts of H2O, Ar, N2, O2, SOX, NOX, Hg, and other trace gases.