Patent US3612005A successfully refreshed from Google Patents.
US3612005A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Once-through steam generator recirculating startup system
Assignee: Foster Wheeler Inc
•
Filing: 1970-01-12
•
Granted: 1971-10-12
•
Expires: 1990-01-12
Abstract
Abstract A once-through vapor generator including a startup bypass in which the flow in the bypass is at a reduced pressure. In the bypass, the flow is separated into vapor and liquid streams, the liquid stream being recirculated directly to the suction side of the generator main feed pump. A booster feed pump is provided upstream of the main feed pump and in series therewith. The booster feed pump is operative during startup to provide to the suction side of the main feed pump that makeup flow in addition to the recirculated flow necessary to prevent tube burnout in the generator.
Inventors
- 👤 Robert I Lytle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:53
CPC Classifications
F; F22; F22B; F22B35/00; F22B35/06; F22B35/14
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
134 words
A once-through vapor generator comprising a main flow path including, in series flow relatIonship, vapor generating and superheating surfaces; a bypass system connected with said main flow path including flash tank means therein; a main boiler feed pump for supplying liquid to said vapor generating surface, and pressure reducing means to reduce the pressure of the flow in said bypass system, the improvement comprising liquid conduit means connecting said bypass system flash tank means with the suction side of main boiler feed pump to transmit liquid flow from said flash tank means to said suction side; booster feed pump means upstream of the liquid conduit means to transmit makeup flow to the feed pump suction side; further including branch conduit means to transmit swell liquid from said flash tank means to the generator condenser.
Claim 2
Dependent Claim
134 words
A once-through vapor generator comprising a main flow path including, in series flow relatIonship, vapor generating and superheating surfaces; a bypass system connected with said main flow path including flash tank means therein; a main boiler feed pump for supplying liquid to said vapor generating surface, and pressure reducing means to reduce the pressure of the flow in said bypass system, the improvement comprising liquid conduit means connecting said bypass system flash tank means with the suction side of main boiler feed pump to transmit liquid flow from said flash tank means to said suction side; booster feed pump means upstream of the liquid conduit means to transmit makeup flow to the feed pump suction side; further including branch conduit means to transmit swell liquid from said flash tank means to the generator condenser.
Claim 3
Dependent Claim
21 words
The generator of claim 1 wherein the booster feed pump is connected to receive liquid from the generator deaerator storage tank.
Claim 4
Dependent Claim
23 words
The generator of claim 2 including a valve in said branch conduit means responsive to liquid level in the bypass system flash tank.
Claim 5
Dependent Claim
59 words
The generator of claim 3 including a vapor return line from said flash tank means to at least some of said superheating surfaces, valve means therein, and valve controlled vapor branch lines between said flash tank means and the generator condenser, gland seal regulator and deaerator, the valves in said vapor return line, and branch lines being pressure controlled.
Claim 6
Dependent Claim
34 words
The generator of claim 4 including check valve means between said booster pump means and the point of connection of the flash tank means with the suction side of the main boiler feed pump.
Claim 7
Dependent Claim
23 words
The generator of claim 3 wherein said valve in the branch conduit means can be made responsive to pressure in the flash tank.
Claim 8
Dependent Claim
40 words
The generator of claim 4 including burners and control means therefor, part of said control means comprising means responsive to the pressure in the flash tank to limit the flash tank pressure to a predetermined amount by controlling firing rate.
Claim 9
Dependent Claim
178 words
A once-through vapor generator comprising a main flow path including, in series flow relationship, vapor generating and superheating surfaces; a bypass system connected with said main flow path including flash tank means therein; a main boiler feed pump for supplying liquid to said vapor-generating surface; and pressure-reducing means to reduce the pressure of the flow in said bypass system; the improvement comprising liquid conduit means connecting said bypass system directly with the suction side of said main boiler feed pump to transmit liquid flow from the flash tank means to said suction side; booster feed pump means upstream of the liquid conduit means to transmit makeup flow to the feed pump suction side; first valve controlled branch conduit means to transmit liquid flow from the flash tank means to a heat sump, and second valve controlled branch conduit means to transmit vapor flow from the flash tank to the heat sump; said first and second branch conduit means first and second valves being responsive to liquid level in the flash tank and pressure in the flash tank, respectively.
Claim 10
Dependent Claim
178 words
A once-through vapor generator comprising a main flow path including, in series flow relationship, vapor generating and superheating surfaces; a bypass system connected with said main flow path including flash tank means therein; a main boiler feed pump for supplying liquid to said vapor-generating surface; and pressure-reducing means to reduce the pressure of the flow in said bypass system; the improvement comprising liquid conduit means connecting said bypass system directly with the suction side of said main boiler feed pump to transmit liquid flow from the flash tank means to said suction side; booster feed pump means upstream of the liquid conduit means to transmit makeup flow to the feed pump suction side; first valve controlled branch conduit means to transmit liquid flow from the flash tank means to a heat sump, and second valve controlled branch conduit means to transmit vapor flow from the flash tank to the heat sump; said first and second branch conduit means first and second valves being responsive to liquid level in the flash tank and pressure in the flash tank, respectively.
Claim 11
Dependent Claim
25 words
The generator of claim 8 including burner means, control means therefor, said control means being responsive in part to pressure in the flash tank means.
Claim 12
Dependent Claim
27 words
The generator of claim 9 wherein said valve means responsive to liquid level in the flash tank can be made responsive to pressure in the flash tank.
Claim 13
Independent Claim
78 words
A method for starting up a once-through vapor generator comprising the steps of essentially all of the flow to a bypass flash tank wherein the flow is separated into vapor and liquid phases; recycling the liquid phase directly to the generator main feed pump suction side, the vapor phase being returned to the generator main flow path; and adding makeup flow to said main feed pump suction side to replace the vapor phase separated from the recycled flow.
Claim 14
Independent Claim
78 words
A method for starting up a once-through vapor generator comprising the steps of essentially all of the flow to a bypass flash tank wherein the flow is separated into vapor and liquid phases; recycling the liquid phase directly to the generator main feed pump suction side, the vapor phase being returned to the generator main flow path; and adding makeup flow to said main feed pump suction side to replace the vapor phase separated from the recycled flow.
Claim 15
Dependent Claim
21 words
The method according to claim 11 wherein excess swell liquid and excess vapor only are transmitted to the Generator heat sump.
Claim 16
Dependent Claim
20 words
The method of claim 12 wherein the excess vapor amount is minimized by controlling the firing rate of the generator.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-11 | 1975-04-12 | 1975-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-11 | 1979-04-12 | 1979-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-11 | 1983-04-12 | 1983-10-12 | $7700.00 | Window Closed / Lapsed |