Improving Mining Efficiencies with Temperature Consistency

The mining industry is booming right now. The global mining market grew from $2022.6 billion in 2022 to $2145.15 billion in 2023 at a compound annual growth rate of 6.1%.

What’s contributing to the growth? User demand.

The mining market consists of sales of minerals, metals and other valuable materials such as sand and gravel, coal and stone - all of which is extracted and refined at mining locations throughout the world.

Sibelco, a Belgian-based mining company, has over 100 of these locations worldwide. Their specialty is processing the mineral quartz which is used in electronics, solar panels, lighting and much more.

Sibelco’s IOTA® high purity quartz sands are their specialty product in the United States. They are used to produce fused quartz, a material with unique optical, mechanical and thermal properties, which make it indispensable in the manufacture of a wide range of high-tech products.

Products in the IOTA® quartz line for Sibelco are mined from two uniquely pure ore bodies in Spruce Pine, NC.

A Refined Process

To get to the high-quality refined material that is IOTA® quartz, many different steps need to take place first.

“What we’re doing in Spruce Pine is we're taking the rock out of two different mines here in the area and we're separating out the different minerals,” Jason Dale, projects supervisor at Sibelco said. “The major mineral that we are trying to recover is quartz, but there is also feldspar, mica, and some other trace minerals. Our main function is to break the rock up and separate the materials out into products that we can sell.”

During the processing of the materials, many systems are used to support the refinement. Sibelco has done a lot of research at this location to see how to best process their materials for sale, and what they have found is that having a stable, warm water supply is critical to the process and how efficiently it can be completed.

“Water inefficiencies don't allow us to separate the different minerals as efficiently in our processing plant,” Dale added. “We kind of lose efficiency in getting the quartz and the feldspar and the mica separated, and then we have to slow down our production.”

The Need for Consistency

Sibelco’s Schoolhouse location in Spruce Pine, where the IOTA® quartz is refined, is situated in the heart of the Appalachian Mountains. These Spruce Pine mines have been home to the world’s highest quality quartz, which had been mined from this location for more than a century.

While the materials are abundant in Spruce Pine, the warm weather is not. Temperature swings at this location can vary greatly from season to season, and even depending on the time of day. These temperature variations were causing efficiency issues in processing times.

“Our water temperature really increases our tonnage capabilities,” Dale said. “On a warm summer day, things run great. In wintertime though, we were seeing that our tonnage would fall off on what we were able to produce daily. We saw those reactions and those separations happen much less efficiently in cold water and noticed that the 80 degree temperature range was the optimal range for floating all of these minerals out. We needed to find a way to keep that temperature consistent.”

Before learning that temperature was the key to production efficiency, Sibelco was not using any means to heat their water and started to use a steam injection system to improve the process.

“This worked as a temporary solution,” Dale said, “but it was not raising the temperatures to the levels we wanted. We were only seeing a few degrees difference.”

Why Heatec?

Astec specializes in thermal fluid heaters and process heaters which are known throughout many different industries for providing consistent and reliable heat for a variety of applications. Before coming to Sibelco, Dale had experience in the asphalt tank industry where he was introduced to the brand.

“When we were looking to make a permanent installation for water heating, we went down to visit the Heatec plant twice and had Chris Horten from Astec come and visit us as well,” Dale said. “They determined that a thermal fluid glycol heater would be the best solution to not only heat the water, but also to treat it as well since we struggle with our water quality.”

Heatec’s thermal fluid heaters utilize an indirect heating method by heating a liquid medium in the heater which then transfers heat to the end user. In this case they used a water glycol mixture as the transfer fluid.

“We told the Heatec team what we wanted to get out of the system,” Dale said. “We were able to give them the kind of temperatures that we were looking for as well as the water flow rates that we were looking to get, and they built the system from there.”

Heatec was also able to customize a dual heating solution for this location with two heat exchangers for this system.

“In this application, we have to heat two separate streams of water simultaneously and we have to be able to control the temperature to both of them pretty much independently as well,” Dale said. “That was something we kind of worked through with Chris and the Heatec team. We explained our challenges and let them propose a solution for us. They were able to give us the heater itself and then recommend the whole package with the heat exchangers on everything else that they sized out for us.”

The Heatec team was on hand to help Sibelco’s engineers install the system and ensure that everything was running properly during the commissioning process.

Immediate Benefits

Once installed, the processing at the Schoolhouse location was up to peak efficiency.

“Now that we are able to control and really stabilize that water temperature, and fine tune the temperature the way they want, efficiency has increased,” Dale said. “Our operators are not just turning the system on or off, they're able to set the temperature and let it let the system adjust and maintain that heat for them.”

And temperature can be maintained no matter what Mother Nature decides.

“One of the big issues that we had in the past was particularly in the spring,” Dale said. “As it starts to warm up during the day, there'd be fluctuations in the water temperature where it would get hot during the day as the temperature outside comes up, and then drop out as it cools off at night. This system has really helped to stabilize those swings for them. So that's a big benefit.”

Training Instills Confidence

We all know a system is only as good as the people running it, which is why the Sibelco team invested heavily in the training of their people to ensure everything continues to run smoothly.

“We were able to send six employees from our maintenance and operations division to the Heatec Customer Schools to provide them with a good overview of the system,” Dale said.

Astec’s support team is also on-hand post sale should their customers need any assistance.

“Since start-up, our maintenance department has called a few times for some technical support.” Dale said. “Heatec has sent out a technician to answer questions and kind of help out with any issues or any questions they’ve had with the system.”