Compact Stainless Steel Plate Type Air Preheater Of Low Fouling Possibility For Steel Industry

Compact Stainless Steel Plate Type Air Preheater Of Low Fouling Possibility For Steel Industry

Stainless Steel Plate Preheater

Stainless Steel Plate Preheater is an advanced high efficient & energy saving type of preheater, which has the advantages of high efficient heat transfer, low pressure drop, compact structure, corrosion resistance, long service life, low soot accumulation, easy cleaning, etc. It can avoid not only the heat transfer tube burst due to high temperature, low temperature corrosion, easy block-up and premature failure, but also big volume and short service life compared with tube heat exchanger.

Stainless Steel Plate Preheater replaces the traditional tube and heat pipe by plate sheets as heat transfer components. Gas and air (coal gas) transfer heat through the plate sheets where the hot fluid and cold fluid are completely separated. The wall surface of the flowing channel keeps changing and results in enhanced turbulence of flowing fluid so that the performance of heat transfer is improved. Moreover, the plate sheet has a smooth surface and boasts lower fouling resistance.

I Work Principle / Flow

The Stainless Steel Plate Preheater is used for dual preheating system of hot blast stove in blast furnace, where the air preheater and coal gas preheater are arranged. The flue gas at around 300℃ exhausted from the hot blast stove, is separately delivered into the air preheater and coal gas preheater in parallel to preheat the air and coal gas up to 190℃ before they are led into the hot blast stove for combustion and cool down the flue gas to around 140℃ before it is discharged from the stack.

II Specification

Specification sheet reserved

III Advantages

--- Efficient heat transfer performance: The plate type heat transfer component has an overall heat transfer coefficient 1-3 times higher than that of tubular heat transfer component and 30%~100% higher than that of heat tube type. In view that the temperature and size change before and after the heating process, variable flowing channel is designed to ensure optimized overall heat transfer coefficient and minimized resistance drop.

--- Low pressure drop: With same heat exchange area, the flow area of plate type is 5 times bigger than that of conventional heat tube type preheater. When the medium flows in the plate type preheater, it encounters less resistance drop thanks to the straight channel, bigger flow area and shorter distance. Variable flowing channel is designed to ensure optimized overall heat transfer coefficient and minimized resistance drop. Compared with heat pipe type preheater, the plate type reduced the the resistance drop by 20%-60%, which is only 40%-60% of the tubular type.

--- Low fouling: With special corrugated design and smooth heat transfer surface, the plate type preheater hardly has soot accumulated.

--- Compact structure: The plate preheater is of high compact ratio. For tubular type (heat pipe type), it is about 60m²/m³ while for plate preheater, it is 160m²/m³, which is around 3 times higher.

--- Good resistance against high temperature: The heat transfer component of plate preheater is made of high heat resistant stainless steel and can operate safely at a temperature up to 450℃.

IV Application

Project: #3 blast furnace revamp project

Enduser: Fangda Special Steels Science & Technology Co., Ltd.

Supply: Air preheater and coal gas preheater