What to do when the reactor is corroded

Reactor corrosion is a significant issue that affects the lifespan and efficiency of reactors used in industries like chemical, petroleum, food, and pharmaceuticals. Here are the main types and causes of reactor corrosion:

1. **Pitting Corrosion**:

- Occurs primarily in the upper gas phase area of high-pressure reactors.

- Common in reactions where the medium exists in a gas-liquid binary state.

- Poor fluidity and high concentrations of corrosive media damage the passive film on the metal surface, leading to pitting.

2. **Stress Corrosion of the Lower Head**:

- Affects the reactor head, typically formed through spinning.

- Uneven plastic deformation during cold working reduces material plasticity, causing residual stress.

- This stress can lead to brittle fracture and stress corrosion cracking, especially in austenitic stainless steel reactors.

3. **Corrosion in High-Pressure Stainless Steel Reactors**:

- Results from exposure to highly corrosive media at elevated temperatures and pressures.

4. **Corrosion in Steam-Heated Reactors**:

- Condensate forms a gas-liquid state during settling, leading to alkaline corrosion.

- This degrades the protective oxide film on the steel, causing further corrosion.

Understanding these corrosion mechanisms is essential for implementing appropriate preventive measures and extending reactor service life.