Boiler Economizer & Sub-Economizer

What Is an Sub - Economiser in boiler (feed water preheater)

In Coke Dry Quenching (CDQ) process, feed water preheater (Sub-economizer) is an important Boiler Accessories, which is an important equipment to further reduce the inlet circulating gas temperature of CDQ furnace, increase the feed water temperature of deaerator and improve the efficiency of waste heat recovery. The heat transfer effect directly affects the temperature of circulating gas at the entrance of CDQ furnace, and then affects the coke discharge temperature, which has a great influence on the operation efficiency of the whole CDQ system.

H-fined sub-economizer with less ash deposit, strong wear resistance, low flue gas resistance, and high heat transfer efficiency .

Boiler Economizer System drawing

In boilers, economical and high-performance economizers for CFB boilers are heat exchange devices that preheat fluids, usually water, up to but not beyond their boiling point. These economizers recover heat from exhaust gases that are hot but not sufficiently high in temperature for direct boiler use, thereby improving energy efficiency. By utilizing waste heat, they preheat the feed water before it enters the boiler, reducing fuel consumption and enhancing overall boiler performance.

H-fined tube structure

Compared with heat pipe type and spiral fin type feed water preheater, the auxiliary economizer made of H-type fin tube has the following advantages:

→H type fin sub-economizer has less ash deposit.

→ H type fin sub-economizer has strong wear resistance.

→The flue gas resistance of H-type fin sub-economizer is small.

In addition to the above advantages, H-type fin sub-economizer with smaller volume, less material consumption and lower price than heat pipe heat exchanger.