Objectives

The primary objective of this tender is to gather information on commercially available leakage detection technologies applicable to coal-fired power station flue gas Air Cooled Condensers (ACCs). The aim is to identify suitable solutions capable of detecting vacuum leaks, particularly small defects, in large, outdoor ACC structures operating under harsh conditions. The information will inform Eskom’s strategy for implementing effective leak detection systems to improve turbine efficiency, reduce operational costs, and enhance maintenance planning.

Scope

The scope of the tender includes:

• Assessment of existing commercially available vacuum leakage detection technologies suitable for ACCs at coal-fired power stations.
• Application of these technologies to large, outdoor ACC structures with complex geometries and limited access.
• Detection and pinpointing of small vacuum leaks (as small as 1 mm²) from a distance, considering environmental challenges such as high noise levels, wind, and heat.
• Evaluation of technologies that can operate during normal on-load conditions and outages.
• Provision of technical details, operational constraints, and case studies demonstrating effectiveness.

Technical Requirements

The technical requirements for the leakage detection solutions include:

• Capability to detect very small defects (<1 mm²) with high certainty and accurate orientation.
• Ability to monitor large, distributed ACC structures from a distance without direct access to the vacuum boundary surfaces.
• Functionality in noisy outdoor environments with high background noise from fans, wind, and steam flow.
• Operation during both on-load and outage conditions.
• Filtering out background noise to reliably identify leaks.
• Use of equipment such as acoustic sensors, infrared or thermal cameras, drones, and pressure monitoring tools.
• Compatibility with the ACC environment, including high wind speeds, heat, and limited access points.
• Minimal disruption to plant operations during inspection.

Skills Requirements

The skills required for the successful implementation and operation of the leakage detection technologies include:

• Technical expertise in vacuum system leak detection, including infrared thermography, acoustic detection, and drone-based inspection methods.
• Experience in deploying leak detection solutions in large industrial structures, particularly ACCs or similar systems.
• Ability to operate specialized equipment such as thermal cameras, acoustic sensors, and drones in challenging outdoor environments.
• Knowledge of noise filtering and signal processing to distinguish leaks from background noise.
• Capability to interpret inspection data, generate detailed reports, and recommend corrective actions.
• Training and support skills to transfer knowledge to Eskom personnel for ongoing monitoring and maintenance.