Aeseal plc

mining, machinery, water saving, industry, money saving, environment, mechanical seal

Press Release   •   Nov 24, 2010 14:08 GMT

So how efficiently run are Mineral Mines?

The President of Chile, Sebastian Pinera probably answers this question, in part, when just a few weeks after the Chilean ordeal started, he sacked the head of national mining regulator Sernageomin, vowing a major overhaul of the body, which monitors mine safety. This action suggests, some mines have fundamental operational gaps in mine health and safety procedures.

If operational gaps are present in such critical areas, then what about other operational areas; Areas such as environmental conservation and water usage?

Alan Roddis, Engineering Director of AESSEAL plc said, “Mineral extraction is a multi-billion £, $ and Euro industry for each mining country. The returns from a profitable mine can be staggering. However, despite these returns, it should be of little surprise that in some parts of the world, little thought is given to the environmental impact that mineral mining creates”.

Roddis continues, “take the use of flush water in mine pumping applications; sometimes the volume of water involved is immense and taken from non-renewable sources. This practice is still widespread around the world as AESSEAL® experienced with a number of large mining slurry pumps with packed glands in Botswana.

The Debswana operation consisted of various diamond mines at Orapa in Botswana, a dry semi-desert area. Essential to the operation are slurry pumps pumping Kimberlite and Iron Silicate. These applications are amongst the most abrasive in the slurry-pumping world.

The packed glands on the pumps needed flush water injection (Plan 32) into the process media, at a rate of 60L/m to prevent slurry entering the seal chamber. If the water supply failed, damage occurred to the gland within 30 seconds. Only 10% of the flush water was recoverable from the process and a typical train of five pumps consumed 134 million litres per annum of water from underground water sources. Due to constant extraction over many years, the water table was dropping and the supply was threatened.

An official mandate was tabled to reduce water consumption by 10% immediately and 15% in the medium term. Pipelines from various alternative sources were considered. The most effective, and most extreme, was to build a 600km pipeline from the Okovango delta to Orapa at a cost of $US 30M. This could have endangered water levels in the delta, a world heritage site.

The eventual solution was simple. By using modern mechanical seal and system technology, supplied by AESSEAL, the majority of the 134 million litres of water/annum was saved; converting it from an open loop operation (water to drain) into a closed loop operation, similar to what you can find in a domestic central heating system. This is a simple example of the operational inefficiencies that are present in some of the mines around the world”, concludes Roddis.

Now, following the plight of the thirty-three miners in Chile, the world’s eyes are focused on the mining industry. Isn’t it now the perfect time to review the mining industries environmental operations as well as Health and Safety operations?

Alan Roddis
Global Technology Centre
Mill Close
Rotherham, S60 1BZ