A method for exhaust waste energy recovery at the reciprocating gas engine-based polygeneration plant which includes supplying this plant with any on-site available methaneous gas, converting from 15 to 30% of supplied gas into electric or mechanical power and producing a liquefied methaneous gas (LMG) co-product from the other 85-70% of supplied gas, and thereby obviates a need for any specialized refrigeration equipment, refrigerants and fuel for LMG co-production at a rate of 0.4-0.6 ton/h for each MW of engine output and makes possible to increase the LMG co-production rate up to 0.9-1.1 t/MWh at the sacrifice of a fuel self-consumption minimized down to 1-2% of the amount of gas intended for liquefaction.

A diffuser nozzle for a gas turbine engine includes a housing disposed about a nozzle axis and extending between a first nozzle end and a second nozzle end. The housing defines a nozzle duct. A plurality of walls is disposed within the nozzle duct. The plurality of walls subdivides the nozzle duct into a plurality of duct sections. The plurality of walls further defines a plurality of axially-extending duct segments of the nozzle duct such that within a first axially-extending duct segment, the duct cross-sectional area of a first duct section of the plurality of duct sections is greater than the duct cross-sectional area of each other duct section and within a second axially-extending duct segment, the duct cross-sectional area of a second duct section of the plurality of duct sections is greater than the duct cross-sectional area of each other duct section.

Improved processes and systems for removing CO.sub.2 from exhaust gas to substantially prevent such greenhouse gas from being released to the atmosphere. The systems and processes use a) staged cooling of an exhaust gas stream, b) addition of an antifreeze, and c) a combination of non-scraped heat exchangers and scraped heat exchangers to separate CO.sub.2 from an exhaust stream while reducing or minimizing accumulation of ice on surfaces within the system.

A method for exhaust waste energy recovery at the internal combustion engine polygeneration plant with the gas engine or gas turbine prime movers which includes supplying this plant with any on-site available methaneous gas (MG), converting from 20 to 30% of supplied MG into electric or mechanical power and producing a liquefied MG (LMG) co-product from the other 80-70% of supplied MG at a rate of 0.5-0.9 ton/h for each MW of engine output through converting and harnessing an engine exhaust as an effective refrigerant.

A process is provided for separating syngas fuel into a CO-rich stream for feeding to oxyfuel combustor means of CO2 turbine means and a H2-rich stream for feeding to air-fuel gas turbine means for generating power provides opportunity to realize operating and equipment advantages.

Methods and systems for increasing efficiency of combustion in a turbine, methods including expanding in an expansion unit a pressurized fluid stream to form an expanded, cooled fluid stream; exchanging heat between an oxygen containing stream and the expanded, cooled fluid stream to reduce temperature of the oxygen containing stream to a reduced temperature and create a reduced temperature turbine compressor inlet oxygen containing stream; and compressing the reduced temperature turbine compressor inlet oxygen containing stream to an operating pressure of the turbine, where the step of compressing the reduced temperature turbine compressor inlet oxygen containing stream is more efficient than compressing the oxygen containing stream.

A process for producing ammonia and a derivative of ammonia from a natural gas feed comprising conversion of natural gas into a make-up synthesis gas; synthesis of ammonia; use of said ammonia to produce said derivative of ammonia, wherein a portion of the natural gas feed is used to fuel a gas turbine; power produced by said gas turbine is transferred to at least one power user of the process, such as a compressor; heat is recovered from exhaust gas of said gas turbine, and at least part of said heat is recovered as low-grade heat available at a temperature not greater than 200 C., to provide process heating to at least one thermal user of the process, such as CO.sub.2 removal unit or absorption chiller; a corresponding plant and method of modernization are also disclosed.

Systems and methods are provided for a turbocharger system for use with a process gas capture system. In one example, the turbocharger system comprises: a heat exchanger positioned to receive inlet gas from a gas generating system via a first inlet; a low pressure compressor driven by a low pressure turbine and coupled to a first outlet of the heat exchanger; a mid-pressure compressor driven by a mid-pressure turbine and coupled in series with the low pressure compressor, the mid-pressure compressor configured to receive low pressure compressed gas from the low pressure compressor; and a high pressure compressor driven by a high pressure turbine and coupled in series with the mid-pressure compressor, the high pressure compressor configured to receive mid-pressure compressed gas from the mid-pressure compressor and output high pressure compressed gas to the process gas capture system and a second inlet of the heat exchanger.

A turbocharger includes a center housing, a turbine connected on one side of the center housing, the turbine including a turbine wheel connected to a shaft, the shaft extending through the center housing, and a compressor connected on an opposite side of the center housing, the compressor including a compressor wheel connected to the shaft opposite the turbine wheel. The shaft includes a cylindrical body having a centerline, a bore extending into the body adjacent the compressor wheel, and a stublet having an internal end engaged in the bore, and an external end connected to the compressor wheel.

A power generation system burns a fuel in a gas in a combustion chamber, producing one or more combustion products and heating a working fluid, preferably supercritical CO.sub.2, that is chemically the same as a combustion product. The working fluid is mixed with the combustion products to form a combustion output mixture which is used in a turbine to drive a shaft of the turbine connected with a generator, producing electricity. The turbine outputs an exhaust that goes to a working fluid recycling system that connects the turbine outlet with the combustion chamber. The fluid recycling system has a radial compressor that receives and pressurizes the exhaust mixture and sends it to a chamber that has a bleed outlet and a recycling outlet. The recycling outlet transmits a recycled portion of the exhaust mixture to the combustion chamber, and the bleed outlet carries an excess portion of the exhaust mixture that is not to be recycled to an extraction system that removes it from the power generation system for use in other applications.