About Minera Los Pelambres
Minera Los Pelambres is a Chilean mining company engaged in the exploration and production of copper concentrate to its customers. The company has operated in the province of Choapa in the Coquimbo region since 1999. Its processing capacity averages 210,000 tonnes of ore per day. Minera Los Pelambres is the seventh largest copper producer in the world. Close to the mine there are around 40 rural communities devoted mainly to agriculture and livestock. Therefore commitment to protecting the environment is a high priority for the company.
Once mined, the copper ore is mixed with water and transported via pipelines to the end destination, where it is processed. Such pipelines are known as slurry pipelines. These pipelines generally transport ore over very long distances. Typical materials that are transferred in such pipelines include coal, copper, iron, phosphates, and oil sands.
Transportation via pipelines has a great economic advantage over railroad transport and much less noise disturbance to the environment, particularly when in remote areas.
The challenge
When implementing leak detection systems on slurry pipelines the challenges faced are far reaching. The water that is injected between the batches of product changes the flow readings. When the water batch is injected over a long period of time the pipeline hydraulics change, therefore affecting the conditions that the leak detection system has to work within. Furthermore, if the concentrate plant is at a very high altitude and it needs to be transported to a point lower in altitude choke valves may need to be implemented to dissipate the pressure.
At Minera Los Pelambres the 8” diameter pipeline travels 120 km with several pressure sensors at intermediate distances with large elevation changes and choke valves along the line.
The situation
To detect and mitigate the effects of any leak of copper concentrate into the water source, Minera Los Pelambres looked to further support their commitment to the environment by implementing leak detection systems on the pipeline.
Atmos was selected because of its reputation and expertise. The Atmos system is designed to address such issues that any slurry pipeline such as the one in Minera Los Pelambres may face.
The solution uses the corrected flow balance in conjunction with sophisticated statistical techniques to provide reliable and accurate leak detection and location. It has been proven on many pipelines that experience severe transients along with many other challenging scenarios.
Atmos Pipe uses the powerful Sequential Probability Ratio Test (SPRT) and pressure and flow analysis to optimize the leak detection. Atmos Pipe is the only statistical system installed on the Minera Los Pelambres pipeline. At each new sample the corrected flow difference is used to calculate the probability of a leak being present. The system identifies if the statistical mean of the corrected flow difference increases compared to what is normal, then the probability of a leak will increase. If this increase in corrected flow difference persists for longer than the leak detection time, then a leak alarm will be generated.
A full training programme was included in the project delivery, the maintenance engineers have been trained to ensure that they are fully versed with the Atmos system.
Why Atmos
The Atmos system is currently outperforming all other leak detection solutions implemented on the pipeline. Tests undertaken saw the Atmos system detecting all leaks in the fastest response time.
Furthermore, the operators trust the system, given its high reliability and Atmos’ support. The low leak detection thresholds and the fast leak detection time mean that the Atmos system will alarm before potentially significant consequences to the environment occur.
The key to a successful project is an excellent working team environment and real proactive involvement from the client. Atmos work very closely with all clients to ensure each member of the client’s team is fully versed and trained on all required aspects of the project. There is a good relationship between Atmos and Minera Los Pelambres, which has been further strengthened by adding an additional rarefaction wave leak detection system, Atmos Wave, on to one of their water pipelines.
The slurry pipelines must be suitably resistant to abrasion from its contents and also corrosion from the soil, in order to avoid environmental disasters, such as leaks. However, implementing a reliable leak detection system has helped Minera Los Pelambres feel safer in the knowledge that they are striving to keep their commitment to protecting the environment.