Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
  • F01K25/00—Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for
  • F01K25/08—Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for using special vapours
  • F01K25/10—Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for using special vapours the vapours being cold, e.g. ammonia, carbon dioxide, ether

Definitions

• This disclosure relates generally to geothermal power plants and, more particularly, to a method and apparatus for operating the turbine inlet and bypass valves thereof.
• a closed loop vapor expansion system including an evaporator/boiler, a turbine, a condenser and a pump, are employed, with the heat from the geothermal source being applied to the evaporator/boiler to heat the working fluid prior to its flowing to the turbine for the purpose of generating electrical power.
• a refrigerant is used as the working fluid, and the system is known as an Organic Rankine Cycle System.
• One such system is shown and described in US Patent 7,174,716, assigned to the predecessor of the assignee of the present disclosure.
• a normally open valve is used as a bypass valve and a normally closed valve is used as a turbine inlet valve.
• the valves are not operable to direct working fluid to the turbine unless sufficient pressure exists in the evaporator to operate the valves.
• the low pressure sides of the valve actuators are vented to the condenser such that the refrigerant remains in the closed loop system rather than entering the atmosphere.
• FIG. 1 is a schematic illustration of a geothermal power plant with the present disclosure incorporated therein.
• FIG. 2 is a schematic illustration of the actuator portion thereof.
• FIGS. 3 A and 3B are cross sectional views of the solenoid valve portion thereof, in non-energized and energized positions, respectively.
• a geothermal power plant 11 which includes a turbine 12, a condenser 13, a pump 14 and an evaporator/boiler 16.
• the power plant 11 is designed to operate with an organic refrigerant, such as R245fa or the like as the working fluid which circulates serially through the system with refrigerant vapor from the evaporator 16 passing to the turbine for the purpose of driving a generator 17 to generate electrical power.
• the resulting lower energy vapor then passes to the condenser 13 with the resulting condensate then being pumped to the evaporator 16 by way of the pump 14.
• the heat source 18 for the evaporator 16 may be of any suitable type such as a naturally occurring geothermal heat source, or a generated heat source such as the exhaust of a gas turbine engine.
• a cooling source 19 such as a cooling tower or a chiller is provided for the purpose of providing cooling water to the condenser 13.
• a turbine inlet valve 21 is provided in a primary flow path line 15 between the evaporator 16 and turbine inlet 22.
• the turbine inlet valve 21 is a normally closed pneumatic valve with an actuator 23 that is shown in Fig. 2 and described more fully hereinafter.
• the actuator 23 is made to operate only by way of a pressurized source, and this source, rather than being independent from the system as in the prior art, is the evaporator 16. That is, pressurized refrigerant vapor flows along line 24 to a pressure regulator 26 which is adapted to provide refrigerant vapor at a predetermined pressure, for example 80 psi.
• the pressure regulated flow of refrigerant vapor then flows along line 27 to a solenoid valve Si, which in turn, is controlled by a control C.
• a solenoid valve Si which in turn, is controlled by a control C.
• the solenoid valve Si is opened, the refrigerant vapor flows into the actuator 23 to open the normally closed pneumatic valve 21.
• Fluidly connected to the primary flow path line 15 is a bypass line 28, leading to a normally open pneumatic valve 29 and then to line 31 leading to the condenser 13.
• the pneumatic valve 29 has a rack-and-pinion actuator 32 similar to the actuator 23 described hereinabove.
• the actuator 32 is pressurized by refrigerant from the regulator 26 flowing along line 33 to the solenoid valve S 2 , which is controlled by the control C.
• the pneumatic valve 29 is normally open unless it is closed by way of the actuator 32 when receiving pressurized gas from the regulator 26 when the solenoid valve S 2 is opened.
• valves 21 and 29 are operated by way of their respective actuators.
• the pressure at the regulator 26 is at a reduced pressure
• the solenoid valves Si and S 2 are closed, and the actuators 23 and 32 are non-operable.
• the normally closed pneumatic valve 21 is closed, and the normally open pneumatic valve 29 is open such that any vapor from the evaporator then flows along line 28, through the normally open pneumatic valve 29, through the line 31 to the condenser 13.
• the actuator 23 includes a pressurized section 34 and a vented section 36, with a sliding piston seal 37 therebetween.
• a return spring 38 biases the sliding piston 37 toward the pressurized section 34.
• the rack-and-pinion causes rotation within the actuator 23 to thereby actuate (i.e. open) the turbine inlet valve 21.
• the vented section 36 is fluidly connected by the line 39 to the condenser 13 so as to allow the rotation, while at the same time disposing of the refrigerant vapor by channeling it to the condenser 13 rather than to ambient.
• the actuator 32 operates in substantially the same manner to close the normally open pneumatic valve 29.
• a solenoid valve Si Shown in Figs. 3A and 3B is a solenoid valve Si with the slide 41 being in a non-energized and in an energized position, respectively. That is, in Fig. 3 A, the slider 41 is in a position at the left as shown such that the pressurized section of the actuator 44 is vented along line 42 to the condenser 13, while the pressurized source is isolated.
• the solenoid valve Si is energized by moving the slider 41 to the right as shown in Fig. 3B, the pressure source is fluidly connected to the pressure section of the actuator, while the vent is isolated.
• the solenoid valve S 2 operates in substantially the same manner.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Control Of Turbines (AREA)
• Fluid-Driven Valves (AREA)
• Engine Equipment That Uses Special Cycles (AREA)

Priority Applications (7)

Applications Claiming Priority (1)

Publications (1)

Family

ID=42005362

Family Applications (1)

Country Status (7)

Cited By (2)

Families Citing this family (1)

Citations (3)

Family Cites Families (12)

• 2008
  • 2008-09-10 AU AU2008361681A patent/AU2008361681B2/en not_active Ceased
  • 2008-09-10 US US13/063,024 patent/US20110162398A1/en not_active Abandoned
  • 2008-09-10 CN CN2008801310493A patent/CN102165191B/zh not_active Expired - Fee Related
  • 2008-09-10 WO PCT/US2008/075819 patent/WO2010030271A1/en active Application Filing
  • 2008-09-10 EP EP08821845.8A patent/EP2331815B1/en not_active Not-in-force
  • 2008-09-10 BR BRPI0823063-3A patent/BRPI0823063A2/pt not_active Application Discontinuation
• 2011
  • 2011-03-10 IL IL211669A patent/IL211669A/en active IP Right Grant

Patent Citations (3)

Non-Patent Citations (1)

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