Rio Tinto Level 6 Refurbishment

Project: Rio Tinto, Level 6 Refurbishment
Main Contractor: Overbury’s Plc    
M & E Contractor: Indoor Climate Facilities Services Limited
Independent Witness: Chesterfield Water Consultants Ltd

Scope

The existing 6th floor heating and chilled systems are to be isolated from the base build system’s and modifications and Fan Coil relocations to be implemented. System comprised of Low Temperature Heating and Chilled Water serving 72 Fan Coil Units. All stages of the implementation, enabling works and flushing / cleaning practices to be agreed, witnessed and approved by Chesterfields representatives.

Prior to the commencement of works, a method of works had to be agreed with the independent witness, taking into account the system components, their age and existing base build treatment chemicals and water quality. As some areas of the systems were old, extra additional tasks were implemented to the cleaning process, such as back flushing fan coil units at the pre dynamic stage.

The system required de-commissioning prior to first fill. The system was flushed at high velocity utilising high head 415 volt temporary pumps and batch work / valve manipulation were required to ensure BSRIA AG 1.2001 minimum flushing velocities were achieved to all areas of the systems.

A 3 day bio-wash utilising high grade Isothiazoline broad spectrum treatments was required, again at velocity, to remove any potential bacteria bio-films present. Our cleaning chemical utilised for the project contains a specially formulated mix for multi metal systems, and includes a tracer ingredient to easily test any area of the systems to ensure even distribution. Water quality levels were continuously monitored and witnessed during this process.

Once the main pipework had been deemed “clean”, back flushing practices were implemented to each and every fan coil unit until satisfactory levels were achieved. Final treatments were installed to prevent scale / corrosion and bacteria biofilm build-up, compatible with existing treatments within the base build. Upon completion of our works, all proof documentation was witnessed and signed.