Project
has ever had ” and currently one of the biggest single build refrigeration system projects in the South African mining industry – at least for the last 10 years . “ You ’ d have to look internationally to find a similar scale project ,” he says . “ We are doing a tailored design for the mine , drawing on all the industry norms and our experience to give them the right solutions ,” says Branch .
The three-year project will see BBE install ten refrigeration machines into the surface refrigeration plant , which will ultimately have up to 70MW of cooling capacity , though Branch emphasises the project involves refrigeration more than ventilation – but the two go hand in hand in a mining environment . The company broke ground in October last year , starting with civil works for the major structures of the plant . This first phase of the project will be completed by November 2024 , with work on the 12-month construction of the fan station set to start midyear this year . The second phase of the project will see additional work on the refrigeration plant , with final commissioning slated for mid-2027 . The ventilation and cooling requirements were laid out as part of the pre-feasibility , feasibility and front-end engineering work , evolving through several rounds of iteration as the mine design was refined . Branch lists the primary prerequisites of the HVAC & R element as : what is the required ventilation through the mine in cubic meters per second of air ; and how many megawatts of cooling into the mine are required .
“ From that we then determined the split between cooling in the form of cold water going underground and surface air cooling .” The detailed design specifications such as what pipes and switchgear , types of instruments are to be Andrew Branch , director at BBE Projects . used , came out of the overarching project list of specifications that all contractors have to adhere to .
Branch explains that the chilled water is piped underground to the deep levels of the mine while the air is chilled on surface , then drawn down the material shaft and rock shaft to be redistributed underground . The cooling requirements for mine ventilation are determined by the life-of-mine design . There ' s a wide range of factors that influence it : surface ambient conditions , the extent
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RACA Journal I May 2023 www . refrigerationandaircon . co . za