FLSmidth breaks world record in Chile

FLSmidth made history when it delivered and installed its first 40’ diameter SAG mill, the world’s largest, to the Esperanza copper mine in Chile in 2010. The delivery also included two 27’ ball mills, making it the largest equipment supply ever.

Breaking world records might not be new to FLSmidth, but managing and coordinating the design, delivery, and installation of the world’s largest equipment supply takes some effort. The 40’ diameter SAG mill and the two 27’ ball mills, installed in December 2010, are expected to be fully operational by the end of the first quarter 2011.

Located in the desert about two hours flying time north of Santiago, Chile, the Esperanza plant is designed to mine and process copper bearing ore at a continuous rate of 4303 tonnes per hour, or over 100,000 tonnes per day. With no readily available water source, the plant pumps seawater from the Pacific Ocean, roughly 145 kilometres from the site. Used in the wet process, a staggering 181,000 litres of seawater is consumed per minute. Copper concentrate, the end product, is then pumped back down to the port close to the city of Antofagasta for worldwide commercial distribution.

Before the Esperanza order, FLSmidth’s largest SAG mill measured 38’ and its ball mills, 26’. To the average person, the difference between a 38’ and a 40’ SAG mill is a mere two feet. However, diameter growth has exponential consequences, and the two extra feet of mill capacity required some serious planning and coordination with everyone involved. The motor size and power draw, foundation loadings, bearing size and capacity, mill shell thickness and flange design, casting requirements, head and shell segmentation, as well as several other variables were all part of the design considerations. So, ‘just a few more feet’ is not quite as straightforward as one may think.

A massive project, FLSmidth’s experience from two other large, world-class projects (Andacollo and Los Pelambres expansions in Chile), proved invaluable. Working in close cooperation with the customer, consultants and the motor supplier, a number of meetings were held to discuss design issues and keep the mega project on track. The open dialogue proved vital to the smooth, on-time delivery and erection of the huge 40’ SAG mill.

Designing, manufacturing and delivering on time was just one of the many challenges. The success of a project often comes down to how smoothly and efficiently all the pieces come together. An onsite supervisor, 16 field service specialists and an experienced team of FLSmidth® field service personnel for the many different FLSmidth® product lines worked closely with the Project Management team and suppliers to ensure that the entire project came together onsite.

Based on our extensive experience with previous large diameter mill projects, together with a flexible approach and willingness to adjust our existing project model, the project was completed on-time and on budget. An important step forward for SAG mill development, and mega project management, FLSmidth has proved its ability to adapt, think fast, and get the job done.

Since the Esperanza contract was signed in 2007, FLSmidth has been awarded projects with a total of seven additional
40’ SAG mills. The success of the Esperanza and other large projects have proven FLSmidth has the experience to successfully execute the next seven 40’ mill deliveries.

Some interesting facts about the new mills
The total power needed for the ore grinding in the primary SAG mill and the two secondary ball mills for the Esperanza Project was nearly 60,000kW. The SAG mill motor rating is 22.4 MW and each ball mill is 18.6 MW. All the mills are equipped with gearless ‘GMD’ drive and control systems provided by ABB out of Baden Switzerland. Also included in the order for Esperanza are 26 WEMCO Supercells which are the world’s largest 300m3 flotation cells. This will be the first full plant in the world to commission 300m3 cells that were piloted and developed at the Kennecott plant in Salt Lake City, Utah. Esperanza is a unique application using the WEMCO 300m3.

CONTACT: Kenneth Boice