What is Raph in thermal power plant?

What is Raph in thermal power plant?

RAPH is an rotating plate regenerative air preheater which is used to collect heat from the flue gas and then uses this heat to heat the atmospheric air and sends it inside the boiler.

Why Scaph is used in power plant?

In SCAPH the low temperature ambient air is heated by low pressure steam to avoid cold-end corrosion. Apart from that pre heating combustion air by usage of SCAPH during unit light up aids in reduction of fuel oil consumption by enabling operators to take pulverisers early.

What is Raph in boiler?

Air pre-heater is an important boiler auxiliary which primarily preheats the combustion air for rapid and efficient combustion in the furnace serving as the last heat trap for the boiler system, a regenerative air preheater typically accounts for over 10\% of a plants thermal efficiency on a typical steam generator.

What is the function of economizer?

Economizers are mechanical devices intended to reduce energy consumption or perform a useful function such as preheating a fluid. In basic terms, an economizer is a heat exchanger.

What is the function of reheater in the boiler?

A reheater is basically a superheater that superheats steam exiting the high-pressure stage of a turbine. The reheated steam is then sent to the low-pressure stage of the turbine.

Why soot blower is used in the boiler?

A sootblower is a device for removing the soot that is deposited on the internal furnace tubes of a boiler during combustion to prevent plugging of the gas passes and maintain boiler efficiency.

What is the function of safety valves in the boiler?

Explanation: The function of safety valve is to prevent the excessive steam pressure inside the boiler drum exceeding the design pressure.

What are the functions of economizer and superheater in thermal power plant?

Since the super heater steam has a lot of energy the super heater is used for reduce the temperature of the steam, the economizer helps in minimizing the conservation of energy and re-heater is used for increasing the thermal efficiency of the boilers.

What is economizer and superheater?

As nouns the difference between superheater and economizer is that superheater is a component of a boiler system that heats the steam produced above its saturation temperature to prevent it condensing, and in case of a steam engine to improve its efficiency while economizer is a person who avoids waste.

What is the use of scaph in a gas boiler?

It is used to recover heat from exhaust flue gas to preheat the combustion air. It used during startup of the boiler. During startup there is no flue gas available to preheat the combustion air. So air is passed through SCAPH. Steam for SCAPH is obtained from packaged boiler.

What is the difference between an air pre heater and scaph?

RAPH – Air pre heaters are the heat tranfer devices which transfer the heat from hot flue gases to primary air. SCAPH (Steam coil air pre heaters) – used during start up conditions of boiler, purpose is the same to increase the temperature of primary air.

What is the pressure drop in a scaph?

Generally, 20 to 25 mmwc pressure drop occurs in the SCAPH due to its complex geometry. SCAPH is taken into service when ambient temperature falls and reduces the flue gas outlet temperature of APH. SCAPH is also taken into service during unit start up and low load operation.

What is the purpose of a PA fan in a power plant?

In power plants, the PA fans supply air for conveying of the pulverized coal from coal mills to the furnace area. These primary air fans produce a high pressure to push the coal and air mixture through pulverizer into the furnace.