High Efficient Refineries Air Preheater With Stainless Steel Corrugated Plate Sheets

High Efficient Refineries Air Preheater With Stainless Steel Corrugated Plate Sheets

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 of heat pipe heat exchanger, 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.

Work Principle / Flow

• For steel industry: 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.
• For petrochemical industry 1: The Stainless Steel Plate Preheater is used for waste heat recovery system of heater, where the plate air preheater is arranged. The hot flue gas exhausted from the heater is led into the air preheater to preheat the air before it is introduced into the heater for combustion. Then the flue gas is led into the low temperature & corrosion resistant enamel plate air preheater, where the flue gas is cooled down to 100℃ and then discharged from the chimney.
• For petrochemical industry 2: The Stainless Steel Plate Preheater is used in the waste gas preheating system of incinerator, where the plate waste gas preheater is arranged. The hot flue gas exhausted from the incinerator is led into the plate waste gas plate preheater to preheat the waste gas before it is led into the incinerator for combustion. While the flue gas is led into the air preheater or economizer for cooling, where the flue gas is cooled down to around 100℃ and then discharged from the chimney.

Specification

Advantage

1. 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.
2. 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 resistance drop by 20%-60%, which is only 40%-60% of the tubular type.
3. 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℃.
4. High reliability: The plate preheater design prevents dew point corrosion and the construction material is highly resistant against high temperature. The flow channel design takes the coal gas characteristics into account and eliminates dead area. The gas inlet nozzle is jacked and coated and a proper flow velocity is applied to avoid abrasion to the plate sheets. All these contribute to greatly improved reliability
5. Low fouling: With special corrugated design and smooth heat transfer surface, the plate type preheater hardly has soot accumulated.
6. 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.

Typical Case

150t/h coal fired boiler natural gas fuel revamp, at Sinopec Jiujiang Corp.