Gas turbine and pressurized water reactor steam turbine combined circulation system

Abstract

Disclosed is a gas turbine and pressurized water reactor steam turbine combined circulation system, using a heavy duty gas turbine and a pressurized water reactor steam turbine to form a combined circulation system. Heat of the tail gas of the gas turbine is utilized to raise the temperature of a secondary circuit main steam from 272.8 C., and the temperature of the secondary circuit main steam slides between 272.8 C. and 630 C. according to different pressurized water reactor steam yields and different input numbers and loads of the heavy duty gas turbine. The system has a higher heat efficiency than that of the pressurized water reactor steam turbines in the prior art; and as for the electric quantity additionally generated by gas, the heat efficiency of the system is also significantly higher than that of gas-steam combined circulation in the prior art.

Claims

1. A gas turbine and pressurized water reactor steam turbine combined circulation system, comprising: a steam turbine high-pressure cylinder (1), a steam-water separation reheater (2), a steam turbine low-pressure cylinder (3), a main steam reheat shutoff valve (4), a condenser (5), a number one high-pressure heater (6), a second circuit main feed water pump (7), a deaerator (8), a number three low-pressure heater (9), a number four low-pressure heater (10), a number five low-pressure heater (11), a number six low-pressure heater (12), a condensate pump (13), a waste heat boiler superheater (14), a waste heat boiler high-pressure economizer (15), a waste heat boiler low-pressure economizer (16), a steam generator (17), a pressurized water reactor (18), a first circuit main feed water pump (19), a gas turbine (20), a steam-water separation reheater bypass valve (21), a first-stage steam extraction reheat shutoff valve (22), a distributed control system; heat generated by nuclear fuel rod in the pressurized water reactor (18) generates second circuit saturated steam in steam generator (17) through circulating first circuit pressurized water; a saturated steam outlet of the steam generator (17) is connected to a steam inlet of the waste heat boiler superheater (14); a steam outlet of the waste heat boiler superheater (14) is connected to a steam inlet of the steam turbine high-pressure cylinder (1) through a main steam valve and a speed control valve; wherein the steam outlet of the waste heat boiler superheater (14) is connected to a main steam inlet of the steam-water separation reheater (2) through the main steam reheat shutoff valve (4); and wherein the first-stage steam extraction outlet of the steam turbine high-pressure cylinder is connected to a first-stage steam extraction inlet of the steam-water separation reheater (2) through the first-stage steam extraction reheat shutoff valve (22); a water side of the waste heat boiler high-pressure economizer (15) is connected in parallel with a water side of the number one high-pressure heater (6), to heat a high-pressure feed water at an outlet of the second circuit main feed water pump (7) in a split manner; a water side of the waste heat boiler low-pressure economizer (16) is connected in parallel with a water side of a low-pressure heater group constituted by the number three low-pressure heater (9), the number four low-pressure heater (10), the number five low-pressure heater (11) and the number six low-pressure heater (12) which are connected in series, to heat condensate at an outlet of the condensate pump (13) is heated in a shunt manner; a turbocompressor inlet of the gas turbine (20) draws in air through an air filter group, and compressed air is mixed with natural gas and fully burned in the low nitrogen combustion system of the gas turbine (20), and high-temperature and high-pressure gas applies work in a gas turbine group of the gas turbine (20) to drive a turbogenerator at a side of the gas turbine; steam exhaust at the gas turbine group of gas turbine (20) enters a smoke-side inlet of a gas turbine waste heat boiler comprising the waste heat boiler superheater (14), the waste heat boiler high-pressure economizer (15), and the waste heat boiler low-pressure economizer (16) through a smoke duct; a smoke-side outlet of the gas turbine waste heat boiler is connected to a chimney or smoke is exhausted by a cooling tower in a manner of integrated chimney and cooling tower; a heavy-duty gas turbine and a pressurized water reactor steam turbine form a combined circulation system, and the heat of steam exhaust of the gas turbine is used to raise a main steam temperature of the second circuit from 272.8 C., where depending on different steam output of the pressurized water reactor as well as number and load of the heavy-duty gas turbine, the main steam temperature of the second circuit is operated in the range of 272.8 C. to 630 C.; wherein the distributed control system coordinates the control of the pressurized water reactor (18), the gas turbine (20), the steam-water separation reheater (2), the main steam reheat shutoff valve (4), the first-stage steam extraction reheat shutoff valve (22), the steam-water separation reheater bypass valve (21), the steam turbine high-pressure cylinder (1), and steam turbine low-pressure cylinder (3), where depending on different steam output of the pressurized water reactor as well as number and load of the heavy-duty gas turbine, the main steam temperature of the second circuit is operated in the range of 272.8 C. to 630 C.; wherein the steam turbine high-pressure cylinder (1) is of dual flow and tangential steam admission with a rotor speed of 1500 rpm or 1800 rpm, where its flow capacity is designed based on simultaneous realization of both highest steam admission temperature and highest mass flow rate; materials used for a rotor, a high-temperature steam admission chamber, nozzles and blades of the steam turbine high-pressure cylinder (1) meet requirements for continuous operation at the highest steam admission temperature; strengths of the rotor, the high-temperature steam admission chamber, the nozzles and the blades of the steam turbine high-pressure cylinder (1) meet requirements of the simultaneous realization of both the highest steam admission temperature and the highest mass flow rate and have sufficient safety allowance; wherein the steam turbine low-pressure cylinder (3) is constituted by three or four coaxial low-pressure cylinders of dual-flow and tangential steam admission depending on different operation backpressure; a steam admission temperature of the steam turbine low-pressure cylinder (3) is operated in the range of 343.5 C. to 253.6 C.; a maximum flow capacity of the steam turbine low-pressure cylinder (3) is designed based on a steam admission temperature of 343.5 C.; when a load of the gas turbine (20) is reduced, a steam admission temperature of the steam turbine low-pressure cylinder (3) is reduced to near 253.6 C., the main steam reheat shutoff valve (4) is switched on, and the steam-water separation reheater bypass valve (21) is switched off, so that the steam admission temperature of the steam turbine low-pressure cylinder (3) is not lower than 253.6 C.; when a load of the gas turbine (20) becomes 0, the first-stage steam extraction reheat shutoff valve (22) is switched on; the gas turbine (20) is constituted by three H-class gas turbines; the three H-class gas turbines respectively drive respective turbogenerators; a gas turbine steam exhaust from the outlets of the gas turbine groups of the three H-class gas turbines is discharged into a gas turbine waste heat boiler; the steam-water separation reheater (2) is constituted by six or eight steam-water separation reheaters, that is, each steam admission and guide pipe of the low-pressure cylinder is equipped with a steam-water separation reheater; each steam-water separation reheater is equipped with a corresponding main steam reheat shutoff valve, a first-stage steam extraction reheat shutoff valve and a steam-water separation reheater bypass valve; when the steam-water separation reheater bypass valve is switched on, a pressure difference between an inlet and an outlet of the steam-water separation reheater does not exceed 15 kPa; wherein the gas turbine waste heat boiler comprises the waste heat boiler superheater (14), the waste heat boiler high-pressure economizer (15), and the waste heat boiler low-pressure economizer (16); horizontal arrangement; the waste heat boiler superheater (14) is constituted by three stages superheater heating surfaces of high-temperature stage, medium-temperature stage, and low-temperature stage, and is arranged in a counter-flow manner with respect to the smoke duct; the waste heat boiler high-pressure economizer system is equipped with corresponding regulating valve groups for regulating flow distributions at a water side of the waste heat boiler high-pressure economizer (15) and at a water side of the number one high-pressure heater (6); and wherein the low-pressure economizer system configuration of the waste heat boiler is equipped with corresponding regulating valve groups for regulating flow distributions at a water side of the waste heat boiler low-pressure economizer (16) and at a water side of a low-pressure heater group constituted by the number three low-pressure heater (9), the number four low-pressure heater (10), the number five low-pressure heater (11), and the number six low-pressure heater (12) connected in series.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is the system diagram of a gas turbine and pressurized water reactor steam turbine combined circulation system

(2) In FIG. 1:

(3) 1 steam turbine high-pressure cylinder,

(4) 2 steam-water separation reheater,

(5) 3 steam turbine low-pressure cylinder,

(6) 4 main steam reheat shutoff valve,

(7) 5 condenser,

(8) 6 number one high-pressure heater

(9) 7 second circuit main feed pump,

(10) 8 deaerator,

(11) 9 number three low-pressure heater,

(12) 10 number four low-pressure heater,

(13) 11 number five low-pressure heater,

(14) 12 number six low-pressure heater,

(15) 13 condensate pump,

(16) 14 waste heat boiler superheater,

(17) 15 waste heat boiler high-pressure economizer,

(18) 16 waste heat boiler low-pressure economizer,

(19) 17 steam generator,

(20) 18 pressurized water reactor,

(21) 19 first circuit main feed pump,

(22) 20 gas turbine,

(23) 21 steam-water separation reheater bypass valve,

(24) 22 first-stage steam extraction reheat shutoff valve.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

Example 1

(25) A preferred embodiment of the present disclosure will now be described with reference to FIG. 1 with an AP1000 PWR, steam generator, redesigned steam turbine generator group and three H-class gas turbines and associated waste heat boilers as an example.

(26) The present disclosure discloses a gas turbine and pressurized water reactor steam turbine combined circulation system, comprising: a steam turbine high-pressure cylinder (1), a steam-water separation reheater (2), a steam turbine low-pressure cylinder (3), a main steam reheat shutoff valve (4), condenser (5), a number one high-pressure heater (6), a second circuit main feed water pump (7), a deaerator (8), a number three low-pressure heater (9), a number four low-pressure heater (10), a number five low-pressure heater (11), a number six low-pressure heater (12), a condensate pump (13), a waste heat boiler superheater (14), a waste heat boiler high-pressure economizer (15), a waste heat boiler low-pressure economizer (16), a steam generator (17), a pressurized water reactor (18), a first circuit main feed water pump (19), a gas turbine (20), a steam-water separation reheater bypass valve (21), a first-stage steam extraction reheat shutoff valve (22), a DCS distributed control system; heat generated by nuclear fuel rod in the pressurized water reactor (18) generates second circuit saturated steam in steam generator (17) through circulating first circuit pressure water; a saturated steam outlet of the steam generator (17) is connected to a steam inlet of the waste heat boiler superheater (14); a steam outlet of the waste heat boiler superheater (14) is connected to a steam inlet of the steam turbine high-pressure cylinder (1) through a main steam valve and a speed control valve; the steam outlet of the waste heat boiler superheater (14) is connected to a main steam inlet of the steam-water separation reheater (2) through the main steam reheat shutoff valve (4); the first-stage steam extraction outlet of the steam turbine high-pressure cylinder is connected to a first-stage steam extraction inlet of the steam-water separation reheater (2) through the first-stage steam extraction reheat shutoff valve (22); a water side of the waste heat boiler high-pressure economizer (15) is connected in parallel with a water side of the number one high-pressure heater (6), to heat a high-pressure feed water at an outlet of the second circuit main feed water pump (7) in a split manner; a water side of the waste heat boiler low-pressure economizer (16) is connected in parallel with a water side of a low-pressure heater group constituted by the number three low-pressure heater (9), the number four low-pressure heater (10), the number five low-pressure heater (11) and the number six low-pressure heater (12) which are connected in series, to heat condensate at an outlet of the condensate pump (13) is heated in a shunt manner; a turbocompressor inlet of the gas turbine (20) draws in air through an air filter group, and compressed air is mixed with natural gas and fully burned in the low nitrogen combustion system of the gas turbine (20), and high-temperature and high-pressure gas applies work in a gas turbine group of the gas turbine (20) to drive a turbogenerator at a side of the gas turbine; steam exhaust at the gas turbine group of gas turbine (20) enters a smoke-side inlet of a gas turbine waste heat boiler comprising the waste heat boiler superheater (14), the waste heat boiler high-pressure economizer (15), and the waste heat boiler low-pressure economizer (16) through a smoke duct; a smoke-side outlet of the gas turbine waste heat boiler is connected to a chimney or smoke is exhausted by a cooling tower in a manner of integrated chimney and cooling tower; a heavy-duty gas turbine and a pressurized water reactor steam turbine form a combined circulation system, and the heat of steam exhaust of the gas turbine is used to raise a main steam temperature of the second circuit from 272.8 C., where depending on different steam output of the pressurized water reactor as well as number and load of the heavy-duty gas turbine, the main steam temperature of the second circuit is operated in the range of 272.8 C. to 630 C.; the DCS distributed control system coordinates the control of the pressurized water reactor (18), the gas turbine (20), the steam-water separation reheater (2), the main steam reheat shutoff valve (4), the first-stage steam extraction reheat shutoff valve (22), the steam-water separation reheater bypass valve (21), the steam turbine high-pressure cylinder (1), and steam turbine low-pressure cylinder (3), where depending on different steam output of the pressurized water reactor as well as number and load of the heavy-duty gas turbine, the main steam temperature of the second circuit is operated in the range of 272.8 C. to 630 C.

(27) The steam turbine high-pressure cylinder (1) is of dual flow and tangential steam admission with a rotor speed of 1500 rpm or 1800 rpm, where its flow capacity is designed based on simultaneous realization of both highest steam admission temperature and highest mass flow rate; materials used for a rotor, a high-temperature steam admission chamber, nozzles and blades of the steam turbine high-pressure cylinder (1) meet requirements for continuous operation at the highest steam admission temperature; strengths of the rotor, the high-temperature steam admission chamber, the nozzles and the blades of the steam turbine high-pressure cylinder (1) meet requirements of the simultaneous realization of both the highest steam admission temperature and the highest mass flow rate and have sufficient safety allowance.

(28) The steam turbine low-pressure cylinder (3) is constituted by three or four coaxial low-pressure cylinders of dual-flow and tangential steam admission depending on different operation backpressure; a steam admission temperature of the steam turbine low-pressure cylinder (3) is operated in the range of 343.5 C. to 253.6 C.; a maximum flow capacity of the steam turbine low-pressure cylinder (3) is designed based on a steam admission temperature of 343.5 C.; when a load of the gas turbine (20) is reduced, a steam admission temperature of the steam turbine low-pressure cylinder (3) is reduced to near 253.6 C., the main steam reheat shutoff valve (4) is switched on, and the steam-water separation reheater bypass valve (21) is switched off, so that the steam admission temperature of the steam turbine low-pressure cylinder (3) is not lower than 253.6 C.; when a load of the gas turbine (20) becomes 0, the first-stage steam extraction reheat shutoff valve (22) is switched on.

(29) The gas turbine (20) is constituted by three H-class gas turbines; the three H-class gas turbines respectively drive respective turbogenerators; gas turbine steam exhaust from the outlets of the gas turbine groups of the three H-class gas turbines is discharged into a same waste heat boiler. In another preferred embodiment, the gas turbine (20) is constituted by six F-class gas turbines; in yet another preferred embodiment, the gas turbine (20) is constituted by four G-class gas turbines.

(30) The steam-water separation reheater (2) is constituted by six or eight steam-water separation reheaters, that is, each steam admission and guide pipe of the low-pressure cylinder is equipped with a steam-water separation reheater.

(31) Each steam-water separation reheater is equipped with a corresponding main steam reheat shutoff valve, a first-stage steam extraction reheat shutoff valve and a steam-water separation reheater bypass valve; when the steam-water separation reheater bypass valve is switched on, a pressure difference between an inlet and an outlet of the steam-water separation reheater does not exceed 15 kPa.

(32) The gas turbine waste heat boiler comprises a waste heat boiler superheater (14), a waste heat boiler high-pressure economizer (15), and a waste heat boiler low-pressure economizer (16); horizontal arrangement; the waste heat boiler superheater (14) is constituted by three stages superheater heating surfaces of high-temperature stage, medium-temperature stage, and low-temperature stage, and is arranged in a counter-flow manner with respect to the smoke duct; the waste heat boiler high-pressure economizer system is equipped with corresponding regulating valve groups for regulating flow distributions at a water side of the waste heat boiler high-pressure economizer (15) and at a water side of the number one high-pressure heater (6); the low-pressure economizer system configuration of the waste heat boiler is equipped with corresponding regulating valve groups for regulating flow distributions at a water side of the waste heat boiler low-pressure economizer (16) and at a water side of a low-pressure heater group constituted by the number three low-pressure heater (9), the number four low-pressure heater (10), the number five low-pressure heater (11), and the number six low-pressure heater (12) connected in series.