SX Weir Wall Reinstatement Repairs

SX Weir Wall Reinstatement Repairs

SX Weir Wall Reinstatement Repairs-A01


The Sepon mine is located in Vilabouly district, Suvannakhet province and Trepax have a corrosion mitigation team based on site permanently.

Operating Process

The SX area is a solvent extraction, electrolyte circulation tank, which consists of a concrete rectangular tank separated down the middle by a concrete weir wall, thus forming two square tanks, the whole of the inside area is lined in a 2mm stainless steel liner, The centre wall is shorter and tapered at the top to allow electrolyte solution from the lean side to flow over into the rich side of the tank, this process is refered to as partitioning or leaching and contains. Sulphuric acid content making the whole area very corrosive.

Special Requirements

A highly engineered concrete reinstatement procedure was designed and executed by Trepax innovation. Due to impact damage resulting in splits to the internal SS liner, caused by falling  pipework the highly corrosive electrolyte solution was able to penetrate these splits and attack the concrete structure inside, this has resulted in long term damage and eroding of the concrete within the inner weir wall and inner concrete structure of the external tank walls.

Corrosion Protection

In order for the Stainless steel liner to do its job as a corrosion protective barrier, the Trepax team had to devise and execute a complex and elaborate series of precision core drilling and material insertion location points, this operation was highly dangerous due to the fact that the process vesell was still live and active and contains high levels of sulphuric acid. After the frst stage of core drilling through the outer wall and into the inner middle weir wall was successfully completed. Specialist injection gel was then injected in to these areas of the wall cavity to act as a liquid  bsorbing protective cushion. Once this was achieved a cementitious grouting system was put in to operation, starting at the lowest point frst and systematically injecting all of the predrilled cores upwards, flling the inner weir wall voids to reinstate the concrete loss caused by sulphuric acid attack.

System Specifcation

Systematic coring and drilling operation starting at the lowest injection point and moving upwards.

Injectable hose system with integral valves for sealing construction joints in watertight ructures.

Low viscous, elastic polyacrylic injection resin was injected to absorb the water electrolyte solution within the weir.

Project Details

Location Savanakhet, Laos PDR
Project SX Weir Wall Reinstatement Repairs
Owner LXML Company Limited
Date 2017
Work SX Weir Wall Reinstatement Repairs
System Coring / Drilling & Grout Injection
Area Volume 1 Tonne Of Cementitous Grout
Value US$ 135,500