Going to Great Lengths

In the high-stakes game of mining today, margins are tighter and under more pressure than ever. To remain viable, mining companies are becoming more scientific and are employing the latest technologies to ensure sustained profitability. Increasingly, they are turning to technology partners to provide advanced technical solutions to various mining challenges.

One such example is an international mining major’s recent project in South America which required a cost-effective means of transporting copper concentrate 23km from the relevant mine to the nearest harbour. Intensive investigations revealed that hydro-transportation would be the best means of achieving this. The solution called for two, 23km, 200mm nominal bore (nb) high-pressure HDPElined pipe systems.

In South Africa

For a value-adding hydro-transportation solution, the mining company turned to the US-based company Aegion. The mine which Aegion supplied is a large open-pit copper project under development with phased commissioning having taken place during 2018, with continued ramp-up over 2019.

This project will increase production at the mine from 70Mta to 85Mta, with concentrate production increasing from 150 000t to 270 000t annually. To supply the required ‘spools’ or pipeline sections,

Aegion took the decision to manufacture the 46km of pipe spools at Aegion South Africa, its local subsidiary, the majority shareholders of which are Robor South Africa (40%) and Aegion International (60%). The decision to manufacture in South Africa was based on the fact that Robor had already successfully completed a project for the same client at one of its Zambian operations.

“Regarding the Zambian tailings management facility, it is a great example of one of this client’s best managed and operated lines; and went a long way in affirming the level of value which can be generated when technology is combined with services,” says Johann Scholtz, General Manager of Aegion South Africa.

Exacting specifications

The pipe sections or spools that the company supplied needed to meet very exacting specifications.

The completed pipeline had to be able to withstand the massive internal pressures required to pump concentrate over a distance of 23km. For the client, the unquestioned integrity and reliability of the pipeline was a key consideration, as the hydro-transportation system would be transporting high-value copper concentrate.

“Fortunately, we have the most advanced hydrotransportation intellectual property at our disposal;

as well as pan-African pipeline engineering excellence,” comments Johann.

The challenges in undertaking this project were significant in a number of aspects. After initial technical consultations, the client opted to manufacture the recommended high-pressure HDPE-lined steel spools in 18m lengths. Manufacturing spools to this length is not conventional practice, due to the technical challenges encountered in manufacturing, the logistics hurdles and the high transport costs.

However, the value-add for the client was considerable. For pipeline operators, from an installation, operating and maintenance perspective, the best solution is one continuous pipeline with no joints at all, as the cost of joints can comprise as much as 20% of the cost of a spool. However, in terms of construction and topographical challenges, in reality this is not practical.

Complete re-engineering

“In this instance, our decision to manufacture in 18m spool lengths resulted in a 10% saving on project costs for our client,” explains Johann. This required the complete re-engineering of Aegion SA’s Johannesburg manufacturing facilities, and the construction of a brand-new plant to build the exceptionally long spools. Notably, this new, technically-advanced plant took a mere 80 days to construct and, once in production, produced 700 metres of pipes / spools daily.

“For our industry, this level of production set a new benchmark,” continues Johann. This heightened production was essential to meet the client’s tight shipping schedule with 2 770 abnormal lengths needing to be shipped from Johannesburg to South America in a period of nine weeks.

Aegion South Africa