Media GGH

Application

 

MGGH in power plant is upgraded version of gas gas heater, which mainly consists of flue gas cooler before ESP and flue gas reheater after FGD tower. Different with GGH, it uses water as media for heat transfer. Circulating water in closed loop takes heat away from hot raw gas, and gives it to treated gas.

 

 

System components

 

MGGH mainly consists of flue gas cooler, flue gas reheater, circulating water system, auxiliary steam heating system, soot blower system, makeup water system, chemical dosing system, etc.

 

Working principle

 

First, demineralized water is pumped into water circulation loop. When water reaches to certain level in expansion tank, circulation pump will drive water (65-75℃) into flue gas cooler to absorb waste heat from raw gas, then the heat is released to treated gas when circulating water (100℃) passes through flue gas reheater.

 

Under design conditions, flue gas reheater could increase treated gas temperature up to 75-80℃. Under low load condition, when heat recovered from flue gas cooler is not enough for flue gas reheater, auxiliary steam gas heater is put into operation.

 

Benefits

 

• Different with singular flue gas cooler, cooling unit of MGGH brings flue gas temperature below dew point. Most SO3 in flue gas forms acid mist, and attaches to the surface of dust particles and gets neutralized by alkali matters. Because specific resistance of dust particles are reduced greatly, ESP dust collection performance is improved obviously.
• Reduce water consumption in FGD system.
• Reduce corrosion to flue and stack.
• Increase plume rise, accelerate flue gas diffusion.
• Eliminate sour rain.