Generating high flow rates of nitrogen at remote mine site in northern Mexico

17 December, 2019

In most places on earth, an abundance of oxygen is a good thing. Deep inside the Mimosa coal mine in Mexico’s remote North, however, reducing its concentration was essential to ensure maximum safety within the mine. Thanks to some impressive teamwork, multidisciplinary expertise and cutting-edge technology, Atlas Copco Rental was able to set up a cost-effective solution in no time.

Challenging terrain

Minera del Norte first approached Atlas Copco Rental in early March 2019. Their request? To find a solution that would render the oxygen-rich atmosphere inside their Mimosa coal mine inert. It soon became obvious that the best solution would be to displace the excess oxygen (O2) by injecting the mine with large volumes of nitrogen (N2). Easier said than done, especially given a few of the project’s specific constraints:

  1. The remote location: a rough 5-hour drive from Monterrey in Mexico’s rugged North ruled out the possibility of using liquid nitrogen. It also meant the capacity of on-site power generators was limited.
  2. A very high flow rate: 2,000 CFM was required to maintain safe conditions inside the mine. That’s one and a half times the volume of an Olympic swimming pool every hour, 24 hours a day, 7 days a week for several months!
  3. The urgent timeline: everything had to be operational within just 7 days.

And so, faced with all these constraints, Guillermo Garza, Vice President Operations, Angel Ramos, Area Sales Manager Northern Mexico and their team set about devising a reliable and cost-effective solution for generating N2 on site.

State-of-the-art solution

To displace the excess O2 inside the Mimosa mine, we needed to generate enough N2 of sufficient purity. We proposed to install 2 NGM 1100 nitrogen membrane generators, each combined with 3 PNS high-pressure diesel driven air compressors. Using 2 separate groups not only meant higher flow rates but also extra redundancy in case of any downtime.

Angel Ramos , Area Sales Manager @ Rental Northern Mexico

Both units operated around the clock without fail, delivering over 2,000 CFM of 98% pure N2 for a full 5 months, after which a single unit was kept running for a further 3 months.

Given that the client’s original contract was for only 4 months, it is safe to assume that Minera del Norte was one satisfied customer.

Clear return on investment

The size of the project meant that we could deliver significant economies of scale, Especially when you compare with the cost of trucking in liquid nitrogen on a daily basis, our solution was not only simpler and more reliable but a lot more cost efficient.

Guillermo Garza , Vice President Operations - Rental Mexico

An added bonus of our nitrogen membrane generators is that they run on just 24V of AC current, much like your average model train set. This eliminated the need for heavy and bulky transformers. In fact, the demand on generator capacity – another scarce resource at the remote mine site – was kept to a strict minimum.

Huge team effort

Setting up both units within the extremely challenging deadline called for a coordinated effort between multiple departments including operations, technicians and sales. And since only 1 membrane was available within Mexico at the time, another had to be imported from across the border in Houston, Texas. Given the timeframe and the complicated customs formalities, this was perhaps the biggest obstacle in the team’s path. “Thanks to the team’s flexibility and dedication, along with a lot of creative problem-solving, we had the whole system up and running in less than 7 days!” concludes Guillermo Garza. Needless to say, a job well done all round!

For more information, please contact:

        • Olivia Gambin - Communications Manager, Atlas Copco Specialty Rental Division

At Atlas Copco, we have been turning industrial ideas into business-critical benefits since 1873. By listening to our customers and knowing their needs, we deliver value and innovate with the future in mind. Great ideas reinforce sustainable development. At Atlas Copco Specialty Rental, we team up with our customers to set up state-of-the-art temporary air, flow, steam and nitrogen solutions. Our passionate experts have extensive application and equipment knowledge. We understand our customers' needs and can provide a total solution for any industry, no matter if it is for emergencies or planned projects. We are a division of the Power Technique business area, headquartered in Boom, Belgium and offer specialty rental solutions under several brands around the globe.