Views: 0 Author: Site Editor Publish Time: 2026-06-04 Origin: Site
Working Principle (Petrochemical Flow Layout)
Tube side: Hot flue gas (280~650℃ from reformer/cracking/atmospheric distillation furnace) flows inside seamless tubes, releases sensible heat
Shell side: Cold ambient combustion air crosses outside tube bundles (cross/counter flow), preheated then fed to furnace burners
Core goal: Cut natural gas/fuel gas consumption 10~18%, raise furnace thermal efficiency from 82% up to 90%+
Core Application Scenarios in Petrochemical
Crude Refining Unit: Atmospheric & vacuum distillation heater, catalytic cracking heater
Hydrogen Production: SMR steam reformer furnace (high-temp flue gas, strict anti-corrosion)
Ethylene/Petrochemical Synthesis: Cracking furnace, reforming furnace, alkylation unit process heater
Off-gas Incinerator: Recover heat from waste hydrocarbon flue gas for combustion air preheat
Graded Tube Material Selection (By Flue Gas Temperature & Sulfur Content, Key for Petro Anti-Corrosion)
Operation Zone | Flue Gas Temp | Tube Material | Function |
|---|---|---|---|
High-temperature section (>250℃) | 300~650℃ | Alloy steel / 316L stainless / centrifugal cast alloy tube | Resist high temp oxidation & high-temp sulfur corrosion |
Middle-temperature section (200~250℃) | 220~280℃ | 20# seamless carbon steel / ND low-temp anti-corrosion steel | Cost-effective for non-dew-point zone |
Low-temp cold end (<200℃, dew-point risk) | 120~190℃ | Enamel-coated carbon steel / bimetallic lined tube / borosilicate glass tube | Block sulfuric acid dew-point corrosion (H₂SO₃ from S-containing flue gas) |
Main Structure Types for Petrochemical
① Vertical Tubular APH (Most popular for refinery furnace)
Flue gas down-flow inside tubes, air cross-flow outside shell; compact layout for furnace top installation, equipped with steam soot blower for periodic ash cleaning
② Horizontal Tubular APH
For large-capacity cracking furnaces, easy tube replacement & maintenance, modular tube bundle design
③ Finned Tubular APH
External spiral finned tubes expand heat exchange area by 40~60%, used for low-flue-gas-flow reformer waste heat recovery
Typical Design Technical Parameters
Flue gas inlet temp: 260~620℃; Flue gas outlet temp:130~180℃
Preheated air outlet:150~380℃
Allow pressure drop: Flue side ≤800Pa, Air side ≤600Pa
Heat recovery efficiency:72~83%
Design pressure: Full vacuum ~0.6MPa (per petro pressure vessel code)
