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26 E&MJ; • JANUARY 2016 www.e-mj.com A mineral processing plant represents a major capital investment for any new mine, with more capex usually needed from time to time as optimization routes become apparent after operational experience has been gained. And, given that most mines are far enough away from major supply sources to make equipment transport costs a real consideration, there can be signifi- cant benefit from having components man- ufactured off-site and brought in, as the construction schedule requires, as pre- assembled modules. Add to that the cost of on-site fabrica- tion labor compared to the same work being carried out in dedicated workshops located in areas of established infrastruc- ture; the people involved can live at home rather than in camp accommodation. And as for quality control, there can be no doubt that having complex fabrication undertaken under workshop conditions is almost always better than having the same jobs done in the open in the middle of a construction site. Components tend to fit together better if they are assembled by a workforce that feels comfortable, and where potential fabrication issues can be resolved before they show up in hard steel. Consequently, for some compelling rea- sons, the concept of building processing plants from largely pre-assembled modules has been slowly gaining ground within the mining industry. It has to be remembered, of course, that some locations are more suitable for this approach than others: mines located close to deep water are at an advantage in this respect, since large plant modules can be brought in by ship, unloaded and moved to site with relative ease. Teck's Red Dog mine in Alaska was an early convert to this way of thinking. By contrast, it would be much more challenging to have to transport modules by train or truck where adequate infra- structure does not already exist—with the need to build it for this purpose maybe off- setting any cost advantages that might be won by using modular construction in the first place. A Question of Scale Plant modules come in all shapes and sizes, ranging from units that can comfort- ably be fitted into standard sea containers to those that require the services of spe- cialist heavy-lift contractors to move and install them. In some respects, other industries—such as oil and gas produc- tion—are way ahead of mining in terms of their use of modular concepts, especially for off-shore installations. Nonetheless, modular concepts are being used more widely in the design of mineral processing plants, especially where individual plant components can be pre-assembled. As an example of a container-ready module, at the end of November, Metso announced the award of a contract from the Kazakh company, Saburkhan Tech- nologies, to supply a containerized NW Series wheel-mounted crushing and screening plant. Metso noted that the unit is designed to be dismantled and packed into standard 40-ft (12-m) containers for easier, faster and more cost-efficient trans- port, cutting delivery times and costs as well as speeding setup on-site. At the other end of the scale, and as noted in E&MJ; 's annual review of the Canadian oil sands industry last August (pp. 32–40), construction of the new bitu- men recovery plant at the Fort Hills proj- ect is heavily reliant on modules that are being constructed both in Canada and overseas. The main contractor for the extraction plant, the South Korean firm SK E&C;, is fabricating smaller modules in South Korea; shipped to Alberta, some of these are being joined in Edmonton to form larger units for delivery to site, while Moving modules by road—as shown here in Western Australia—requires good infrastructure and specialist heavy- haul vehicles. (Photo: Fluor) Making the Most of Modules Modular design can give major advantages when companies are constructing processing plants. E&MJ; asks some industry experts in this field for their views and advice. By Simon Walker, European Editor M O D U L A R P L A N T S