Tham khảo tài liệu 'advanced gas turbine cycles episode 10', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | FUEL METHANE OXYGEN Their calculations show remarkably high overall efficiency ranging from 56 at 1300 K to over 64 at 1500 K with r between 20 and 25 . . Plants with combustion modification full oxidation A number of plants have been proposed in which pure oxygen is used for combustion usually in combination with the concept of cycle semi-closure. CBT and CCGT plants with full oxidation D4 D5 . We next consider two semi-closed cycles for co2 removal Cycles D4 and D5 with air replaced as the oxidant for the fuel by pure oxygen supplied from an additional plant. In cycle D4 15 since the fuel is burnt with pure oxygen the exhaust gases contain co2 and H2O almost exclusively Fig. . Cooling the exhaust below the dew point enables the water to condense and the resulting co2 stream is obtained without the need for chemical absorption. The expensive auxiliary plant involved in direct removal of the co2 is not needed but of course there is now the additional expense of an air separation plant to provide the pure oxygen for combustion. Cycle D5 is another variation of a CCGT plant with full oxygenation of the fuel as shown in Fig. again it is a semi-closed cycle using pure oxygen. But now the co2 is abstracted after compression which may require the use of physical absorption plant. For cycle D4 it may be expected that the thermal efficiency will be close to that of the open CBT plant with the same pressure ratio and top temperature. For cycle D5 there will be a penalty on efficiency imposed from the extra compression of co2 before extraction. The Matiant cycle D6 . Fig. shows a more complex and ingenious version of the semi-closed cycle burning fuel with oxygen the so-called Matiant plant 16J. A stage HRSG STEAM I TURBINE G CYCLE COOLER WATER Fig. . Cycle D4. Simple CCGT plant burning methane with oxygen and with low pressure co2 removal. Advanced gas turbine cycles co2 LIQUEFACTION Chapter 8. Novel gas turbine cycles STEAM TURBINE CYCLE FUEL .
