Stainless steel reactor tank inspection and equipment cleaning process requirements

### Reactor Temperature Control and Maintenance

#### **Temperature Control Device Features**

- **Components:**

- Solenoid valve connected to the heat source pipe.

- Temperature sensor installed inside the reactor.

- Cooling water pipe with a water jet and a ring-shaped cooling pipe connected to a solenoid valve.

- Water receiving tube at the reactor's bottom, connected to a water outlet pipe via a solenoid valve.

- **Automation:**

- Uses two temperature sensors and three solenoid valves for automatic temperature regulation, reducing manual labor.

- Simplifies operation, lowers costs, and enhances efficiency.

#### **Stainless Steel Reactor Inspections**

- **Scope of Inspection:**

- **Design Review:** Ensures compliance with design documents.

- **Physical Inspections:** Conducted onsite or abroad for export and import products, respectively.

- **Operational Quality:** Verifies the reactor's performance under operational conditions.

- **Installation Quality:** Assesses proper installation and alignment.

- **Repair Quality:** Ensures repairs meet safety and operational standards.

#### **Scale Removal and Cleaning**

1. **Technical Requirements:**

- **Pickling Temperature:** Optimal at 60°C to balance descaling and corrosion control.

- **Pickling Solution:** Use 81.0% formic acid, 17.0% water, 1.2% buffer, and 0.8% surfactant.

- **Method:** Combine static immersion (2 hours) and dynamic circulation (3–4 hours).

- **Passivation:** Protect exposed metal surfaces after pickling to prevent corrosion.

2. **Steps for Scale Removal:**

- **Flushing:** Remove impurities like mud and scale from the jacket before pickling.

- **Acid Cleaning:** Soak in acid for 2 hours, followed by 3–4 hours of circulation. Alternate forward and reverse flow every 30 minutes.

- **Alkaline Cleaning:** Neutralize with a NaOH and NaHPO₄ solution to prevent corrosion.

- **Water Cleaning:** Rinse thoroughly with softened water to remove residues.

- **Recording:** Document each step to ensure proper cleaning and verification.

By following these procedures, stainless steel reactors can maintain optimal performance, ensuring safe and efficient operation while minimizing manual workload and operational costs.