How efficient is a HRSG?
Sarah Parker How efficient is a HRSG?
The HRSG forms a major part of the steam system. In the combined cycle mode, the efficiency of the combined gas turbine-plus-HRSG system can reach 55–60% (lower heating value basis) with modern advanced machines, while in cogeneration mode, the system efficiency can be as high as 75–85%.
What is the function of HRSG in combined cycle power plant?
The HRSG is a key component of a combined cycle power plant. Its role is to convert as much of the heat as possible from the exhaust gas of the gas turbine into steam for a steam turbine.
What is pinch point in HRSG?
Pinch point is the difference between the gas temperature leaving the evaporator and saturation temperature=Tg3-ts. Fig 1: HRSG temperature profiles. Approach point is the difference between saturation temperature and feed water temperature entering the evaporator= ts -tw2.
How do HRSG work?
An HRSG is a kind of heat exchanger that recovers heat from the exhaust gases of a gas turbine to an extreme degree. The heat is recovered in the form of steam which is served as the power source of a power-generating steam turbine.
Where is HRSG used?
HRSGs can be used to generate steam for district heating or factory processes, or to drive a steam turbine to generate more electricity. Used in cogeneration, HRSGs help bring overall plant efficiency to 85%”90%, and the economic and environmental benefits are well recognized.
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 pinch temperature?
The pinch occurs where the heat transferred is zero, that is at interval number 4, interval temperature 90 °C. This is equivalent to 100°C in the hot stream or 80°C in the cold stream.
What is boiler pinch point?
energy. The temperature between the exhaust gas and the water. Lower pinch temperatures require more heat transfer areas.
What is CPH in HRSG?
In the HRSG, water is heated in the condensate preheater (CPH). The next component is deaerator (DA) which is responsible for removing oxygen and other dissolved gases from the water. The feedwater is pumped and divided into high-pressure (HP) and low-pressure (LP) streams after passing through the DA.
What is the difference between HRSG and package boilers?
The low exhaust gas temperature from gas turbines, typically ranging from 900 to 1050F, generates less steam on unit gas mass basis in the HRSG evaporator compared to a package boiler.
What is an HRSG and how does it work?
An HRSG is a kind of heat exchanger that recovers heat from the exhaust gases of a gas turbine to an extreme degree. The heat is recovered in the form of steam which is served as the power source of a power-generating steam turbine.
What is a heat recovery steam generator (HRSG)?
Overview A heat recovery steam generator (HRSG) is one of the major pieces of equipment in a gas turbine combined cycle power plant that boasts a high thermal efficiency and produces minimal CO 2 emissions. An HRSG is a kind of heat exchanger that recovers heat from the exhaust gases of a gas turbine to an extreme degree.
How to do a temperature profile analysis for a HRSG?
A temperature profile analysis must be done in the unfired mode as shown below. Example: A HRSG generates 600 psig, 750 F steam using feed water at 230 F. Exhaust gas flow is 160,000 lb/h at 950 F.% volume CO2=3, H2O=7, N2=75, O2=15. Calculate the unfired steam using 25 degree pinch and 20 degree approach points.
