What is once through steam generator?
What is once through steam generator?
The OTSG is a vertical shell counterflow straight-tube heat exchanger design which directly generates superheated steam as the feedwater flows through the steam generator in a single pass. BWXT is the exclusive designer and manufacturer of OTSGs for the nuclear industry.
Do steam generators work?
The high pressure of steam exerts pressure on the angled blades of the turbine, causing the shaft to rotate. This mechanical energy is converted into electricity, using the power in the form of a rotating shaft to turn an electric generator. The turbine being built in the image can generate up to 65 MW of electricity.
Are steam generators safe?
The narrow-tube construction, without any large-diameter drums or tanks, means that they are safe from the effects of explosion, even if worked at high pressures. The pump flowrate is adjustable, according to the quantity of steam required at that time.
What does Otsg stand for?
OTSG
| Acronym | Definition |
|---|---|
| OTSG | Office of the Surgeon General |
| OTSG | Once-Through Steam Generator |
| OTSG | Office of Tribal Self-Governance (Rockville, MD) |
| OTSG | Operations Technical Support Group |
What is the difference between HRSG and boiler?
Most of the HRSG’s are internally insulated so that expansion does not affect the external surfaces and the structures. Conventional boilers on the other hand are top supported and free to expand so the insulation is on the outside.
What is a once through boiler?
A steam generator or boiler which operates at pressures above then the critical pressure of working fluid (220 bar for water) is called a supercritical boiler. They are also called once-through boiler because the entire process of heating, steam formation and superheating is done in a single continuous tube.
How efficient are steam generators?
Multistage (moderate to high pressure ratio) steam turbines have thermodynamic efficiencies that vary from 65 percent for very small (under 1,000 kW) units to over 90 percent for large industrial and utility sized units. Small, single stage steam turbines can have efficiencies as low as 40 percent.
What is the basic difference in a boiler and a steam generator?
Compared to steam boilers, steam generators have less steel built into their design, utilizing a single tube coil instead of many smaller diameter boiler tubes. A specialized feedwater pump is used to continuously pump the feedwater through the coil.
What is the process of steam generator?
In a steam-driven turbine system, water is heated in the steam generator to produce high-temperature, high-pressure steam. Steam is then expanded in a turbine to produce electricity from a generator. Turbine steam is condensed back into water in the condenser. A pump then returns the water to the steam generator.
Where is HRSG used?
Packaged HRSGs They can be used in waste heat or turbine (usually under 20 MW) applications. The packaged HRSG can have a water-cooled furnace, which allows for higher supplemental firing and better overall efficiency.
What is the difference between HRSG and Whrb?
A waste heat recovery boiler (WHRB) is different from a heat recovery steam generator (HRSG) in the sense that the heated medium does not change phase.
What is once through boiler What are the advantages of it?
Over the long haul, “once-through” boilers will help save a significant amount of money in fuel costs while also helping to meet sudden changes in speed demand.
How does a steam generator work?
A steam generator uses a once through, forced flow, design to convert the incoming water to steam during the single pass through the water coil. As water passes through the coil, the heat is transferred from the hot gases which causes the water to convert to steam. The generator design does not utilize a steam drum…
Who makes bwbwxt steam generators?
BWXT is the exclusive designer and manufacturer of OTSGs for the nuclear industry. No tube-free lane (eliminates moisture carry-up into superheat regions and localized high velocities) Of the 69 operating pressurized water reactor nuclear power plants in the U.S., 56 had 163 individual steam generators replaced or awarded by 2005.
How many types of steam generators are there?
There are two types of SG: the U-tube SG and the once through SG, as shown in Figures 2 and 3 . In Figure 2 is depicted a U-tube steam generator, which is installed in a wide variety of commercial NSSS, from the early (1957) 90-MWe Shipping port 4 loops system to new 1300-MWe plants.
What is the primary fluid in steam generator?
In the steam generator the primary fluid, water at 150 bar, exchanges heat with the secondary fluid, water at 75 bar, and causes it to boil. The steam, from the steam generator, passes through the turbine, condenser, and is pumped back into the steam generator (SG) as feed water.
