Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
237 words
Method of controlling a PFBC power plant in the event of an operational disturbance affecting a turbine unit driven by the plant, for example a load drop out, said plant comprising - a bed vessel (12) enclosed within a pressure vessel (10) and surrounded by compressed combustion air, said bed vessel containing a bed (22) of fluidizable particulate material, - a gas turbine-compressor unit (34,38,48) driven by combustion gases from the bed vessel (12), - a first cut-off valve (54) in a supply conduit (32) for propellant gas to a turbine (34), - a second cut-off valve (58) in the conduit (50) from a compressor (48) to the pressure vessel (10), - a third cut-off valve (64) in a short circuit conduit (62) between the turbine (34) and the compressor (48), and - a blow-off valve (72) in a conduit (68) for dumping combustion gases from the bed vessel, characterized in that on the occurrence of a disturbance the compressor-turbine unit (34,38,48) is cut off from the bed vessel (12) by closing the valves (54,58) in the supply conduit (32) for propellant gas and the conduit (50) for the supply of compressed air to the pressure vessel, respectively, and is short-circuited by opening the valve (64) in the short circuit conduit (62), and that combustion gases which are dumped into the atmosphere via said blow-off valve (72) are supplied with coolant upstream of said blow-off valve (72).
Claim 2
Dependent Claim
237 words
Method of controlling a PFBC power plant in the event of an operational disturbance affecting a turbine unit driven by the plant, for example a load drop out, said plant comprising - a bed vessel (12) enclosed within a pressure vessel (10) and surrounded by compressed combustion air, said bed vessel containing a bed (22) of fluidizable particulate material, - a gas turbine-compressor unit (34,38,48) driven by combustion gases from the bed vessel (12), - a first cut-off valve (54) in a supply conduit (32) for propellant gas to a turbine (34), - a second cut-off valve (58) in the conduit (50) from a compressor (48) to the pressure vessel (10), - a third cut-off valve (64) in a short circuit conduit (62) between the turbine (34) and the compressor (48), and - a blow-off valve (72) in a conduit (68) for dumping combustion gases from the bed vessel, characterized in that on the occurrence of a disturbance the compressor-turbine unit (34,38,48) is cut off from the bed vessel (12) by closing the valves (54,58) in the supply conduit (32) for propellant gas and the conduit (50) for the supply of compressed air to the pressure vessel, respectively, and is short-circuited by opening the valve (64) in the short circuit conduit (62), and that combustion gases which are dumped into the atmosphere via said blow-off valve (72) are supplied with coolant upstream of said blow-off valve (72).
Claim 3
Dependent Claim
26 words
Method according to claim 1, characterized in that coolant is supplied in such a quantity that the combustion gases are cooled to a temperature below 400°C.
Claim 4
Dependent Claim
33 words
Method according to claim 1 or 2, characterized in that the coolant flow is controlled such that the gases downstream of the coolant injection point attain a constant temperature during the blow-off process.
Claim 5
Dependent Claim
39 words
Method according to any of the preceding claims, characterized in that the coolant flow is controlled such that the gases, downstream of the coolant injection point, attain a temperature below about 400°C but exceeding the acid dew point (120-180°C).
Claim 6
Dependent Claim
19 words
Method according to any of the preceding claims, characterized in that the coolant is in the form of water.
Claim 7
Dependent Claim
21 words
Method according to any of the preceding claims, characterized in that the coolant is supplied from a permanently pressurized coolant container.
Claim 8
Dependent Claim
147 words
PFBC power plant comprising a pressure vessel (10), a bed vessel (12) enclosed within the pressure vessel (10), at least one gas turbine (34), a conduit (32) between the bed vessel (12) and a turbine (34) having a first valve (54), a compressor (48) driven by the turbine, a conduit (50) between the compressor (48)and the pressure vessel (10) with a second valve (58) and a short-circuit conduit (62) between the compressor (48) and the turbine (34) with a third valve (64), characterized in that it comprises a blow-off valve (72) for dumping gases from the bed vessel (10) in the case of an operational disturbance, a device (70,70′) for injecting a coolant into the gas stream upstream of said blow-off valve (72) when the combustion gases are being dumped, and a device (78) for supplying a coolant under a high pressure to the injection device (70,70′).
Claim 9
Dependent Claim
147 words
PFBC power plant comprising a pressure vessel (10), a bed vessel (12) enclosed within the pressure vessel (10), at least one gas turbine (34), a conduit (32) between the bed vessel (12) and a turbine (34) having a first valve (54), a compressor (48) driven by the turbine, a conduit (50) between the compressor (48)and the pressure vessel (10) with a second valve (58) and a short-circuit conduit (62) between the compressor (48) and the turbine (34) with a third valve (64), characterized in that it comprises a blow-off valve (72) for dumping gases from the bed vessel (10) in the case of an operational disturbance, a device (70,70′) for injecting a coolant into the gas stream upstream of said blow-off valve (72) when the combustion gases are being dumped, and a device (78) for supplying a coolant under a high pressure to the injection device (70,70′).
Claim 10
Dependent Claim
26 words
PFBC power plant according to claim 7, characterized in that the blow-off valve (72) is arranged in a conduit (68) directly connected to the bed vessel.
Claim 11
Dependent Claim
33 words
PFBC power plant according to claim 7, characterized in that the blow-off valve (72) is arranged in a conduit (68) connected to the conduit (32) supplying combustion gas to the gas turbine (32,38).
Claim 12
Dependent Claim
33 words
PFBC power plant according to any of claims 7 to 9, characterized in that it comprises a device (83) for injection of a coolant into the freeboard (28) of the bed vessel (12).
Claim 13
Dependent Claim
39 words
PFBC power plant according to any of claims 7 to 10, characterized in that a water injection device (70,70′) for coolant is connected, via a conduit (80) with a valve (82), to a water container (78) pressurized by gas.