Introduction
Tata Steel Limited commissioned a hydraulic surge analysis for its Iron Ore Tailings Thickened Slurry Transfer Pipeline system at Noamundi Iron Mine. The study focused on transient pressure behavior in the 1.2 km pipeline transporting thickened slurry between the High-Rate Thickener (HRT) and the Paste Thickener (DCT).
The primary objective of the hydraulic transient analysis was to evaluate transient pressures, identify potential overpressure and vacuum conditions, and recommend protection strategies to ensure pipeline integrity.
Scope of Work
The study covered the following aspects of the Noamundi pipeline system:
- Pipeline Specifications:
- 18” dia, 7 meters (Pump Suction)
- 14” dia, 33 meters (Pump Discharge)
- 10” dia, 1210 meters (Iron Ore Tailings Thickened Slurry Transfer)
- Key Objectives:
- Determine maximum transient pressures under normal and emergency conditions.
- Identify overpressure and vacuum pressure risks.
- Validate pipe thickness and material specifications.
- Assess compliance with ASME B31.3 and API 5L standards.
The study prioritized surge condition evaluation, identification of pressure spike or vacuum risks, and developing protective measures to maintain pipeline integrity. Advanced hydraulic simulation software was used in accordance with design standards.
Approach and Methodology
Phase 1: Data Collection & System Assessment
- Comprehensive evaluation of operational parameters, pipeline design (PFD, P&ID, Isometric), and fluid characteristics (slurry viscosity and density).
- Identification of surge-prone regions based on elevation profiles, gradients, pump discharge locations, and valve placements.
- Review of steady-state and transient operating conditions, including unplanned startup/shutdown events.
Phase 2: Hydraulic Simulation & Surge Analysis
- Dynamic simulation of the entire slurry pipeline system using advanced hydraulic modeling software.
- Simulation of emergency scenarios such as pump trips, valve closures, and power failures.
- Assessment of pipeline stress under peak transient pressures and minimum vacuum conditions.
- Evaluation of potential cavitation, structural risks, and compliance with the Maximum Allowable Surge Pressure (MASP) per ASME B31.3 standards.
Key Findings
The hydraulic surge analysis for Tata Steel’s Iron Ore Tailings Thickened Slurry Transfer Pipeline confirmed that:
- Transient pressures remained within the pipeline’s design limits, even in worst-case scenarios (e.g., pump trips, rapid valve closures).
- No additional surge mitigation measures were required due to the optimized pipeline design.
- Proper pipeline sizing, controlled pump operations, and gradual valve actuation effectively managed surge events.
Conclusion
This study validates the robustness of Tata Steel’s slurry transfer system, ensuring operational reliability and adherence to industry standards. The hydraulic surge analysis confirmed that the pipeline system operates safely under various transient conditions, reducing risks associated with pressure surges. The findings provide confidence in the current design while reinforcing the importance of controlled operations for long-term pipeline integrity.