Module 5: Guest Speakers

Hello, my name is Barbara Arnold and I will introduce you to an essential part of the mineral industry, mineral and coal processing. Extracting ore from the ground is only the first step in producing the materials that society depends on every day. Before these materials can be used to generate electricity, manufacture steel, produce batteries, or make countless consumer products, they must first be processed to recover the valuable minerals from an ore and dispose of the non-valuable minerals in an environmentally acceptable way.

Today we will explore why mineral processing is so important, the major steps involved, and some exciting new developments in this field.

So why mineral processing? An ore coming from a mine is never a pure mineral. In fact, valuable minerals often make up only a small percentage of the material that is mined. For example, some copper ores only contain 0.27 percent copper. Coal that is mined contains many minerals, including carbonates, clays, and pyrite. We process this coal to remove these minerals so that the coal can meet quality specifications for power plants, coke ovens for steelmaking, and many other applications.

What are the major steps? Although Though every processing plant is different, most follow a similar sequence of operations.

The first step is comminution, which means reducing the size of the material.

Large mined material, say several feet in diameter, is first crushed into smaller pieces using crushers. These smaller particles are then further reduced using other crushers or grinding mills only until the mineral particles become sufficiently liberated from the surrounding unwanted minerals. We never want to overcrush or overgrind minerals as fine or ultra-fine particles are the most difficult to process.

Once the valuable minerals are sufficiently liberated from the gang minerals, various separation techniques are used depending on the properties of the material. Some common methods include sizing, which is based on the particle size of the ore, gravity separation, that's based on specific gravity differences of the minerals, magnetic separation, which is based on differences in magnetic susceptibility, electrostatic separation, which is based on differences in conductivity, and finally froth flotation.

It uses differences in the hydrophobicity, the water-fearing nature of minerals. The hydrophobicity can be natural, like with coal or graphite, or it can be enhanced by the addition of chemicals that attach to the surface of the valuable mineral. We add bubbles to a water or slurry, and the hydrophobic valuable minerals attach to the bubbles and float to be recovered, while the non-valuable hydrophilic or water-loving particles stay in the slurry.

Finally, the concentrate is dewatered and prepared for transportation or further refining. For example, a chalcopyrite concentrate would be processed in a smelter to produce a purified copper product. A clean coal would be shipped to the customer. We take sustainability and environmental responsibility to heart. Processing plants play an important role in sustainable mining. Energy and water are major consumables in mineral processing plants. Modern facilities are designed to recover more valuable material while consuming less water and energy. All operations recycle processed water, reducing freshwater consumption.

The fine discarded material from mineral processing is called tailings. These tailings are often stored in impoundments that have been known to fail unless they have been properly constructed. New tailings management practices include additional dewatering steps so that this material may be dry-stacked rather than impounded.

Tailings management is an important issue in the mineral industry today. Many tailing streams are being evaluated to determine if additional valuable products can be recovered. For example, Rio Tinto has added a tellurium recovery circuit at their Bingham Canyon copper molybdenum concentrator. Tellurium is one of the USGS critical minerals. These innovations support the transition toward a more circular and sustainable mining industry.

And there are many new technologies. Like mining itself, mineral processing is becoming increasingly digital. Many processing plants use online sensors that continuously monitor product quality, automated process control systems, artificial intelligence for process optimization, machine learning to improve recovery, digital twins that simulate plant performance, advanced instrumentation for real-time decision -making.

These technologies allow operators to detect problems quickly, improve efficiency, reduce energy consumption, and maximize mineral recovery. For example, Freeport -McMoran used a digital twin of their Baghdad operation to optimize recovery of copper. They found that they had seven distinct types of ores, and by adjusting pH in froth flotation based on the ore being processed, they greatly improved recovery. Future mineral processing engineers will increasingly combine traditional engineering knowledge with data science and automation.

There are research opportunities in mineral processing. It remains a very active area of engineering research. This includes improving flotation efficiency, reducing energy consumption during grinding, recovering critical minerals from low-grade ores, recycling battery materials and other electronic scrap, processing mine waste, improving water management, and developing more sustainable processing technologies. These advances will help supply the minerals needed for renewable energy, electric vehicles, electronics, and modern infrastructure.

In closing, let me say that mineral and coal processing are essential links between mining and the products that society uses every day. Successful processing transforms raw, mined material into valuable resources while improving efficiency, reducing environmental impacts, and supporting sustainable development. Whether your future career is in mining, mineral processing, metallurgy, civil engineering, mechanical engineering, environmental engineering, or material science, understanding the fundamentals of mineral processing will give you a better appreciation of how the world's natural resources become useful products.

Welcome to the world of mining automation. My name is Dr. Ashish Kumar and I'm an assistant professor of mining engineering at Penn State.

So the mining industry has always promoted engineering innovations to make sure that our operations are safe, they are productive, and sustainable. The advent of automation has boosted this significantly. So today we use digital technologies, artificial intelligence, advanced sensing, and battery operated equipment.

So why do we even care about automation? It's because mining personal work and environment that could be physically demanding and potentially hazardous. The miners may encounter difficult ground conditions. They might be exposed to dust, diesel particulate matter, heat, noise. They may also have to share confined spaces with large mining equipment. And therefore, automating those equipment enables the alleviation of some of those risks because the exposure of miners to those risks is lowered or eliminated.

So in addition to contributing to safety and productivity, automation can also help reduce cost, improve consistency and accuracy. It can also enable us to collect useful data for improved decision-making.

Because every mine has a unique story, depending on the complexity of the task and capability of the equipment that we want to use there, we could have distinct levels of automation. So at lower levels, we are looking at equipment such as drill that we can operate remotely. If you are looking at advanced systems, a classical example could be an equipment that is intelligent enough to make its own decisions without human intervention.

So what's the role of mining engineers in these these operations? They will continue to design and operate these systems. They will have to analyze data to optimize these complex processes.

Automation in surface mines have been especially successful. Let's look at these from point of view of their applications. So let's talk about navigation, drilling, and mapping. So if you look at automated trucks and dozers they use a lot of modern equipment like lidars, cameras, and radars that talk to an onboard computer and they're able to move materials seamlessly from point A to point B with minimal human intervention. If we look at some of the modern drills, they use high -precision GPS systems and they're able to position themselves autonomously at the desired coordinates. All mines use drones now to create topographic maps. They calculate stockpiles, volumes and can monitor slopes. All of these could be time-consuming and sometimes unsafe if done manually.

Automation is also advanced rapidly in underground mines. Let's look at this from the perspective of the type of operations. So if you look at underground hard rock mines, they use remotely operated trucks, production drills, and other smart hauler systems. If you go see a coal mine, longwall mines use automated shearers that are able to position themselves autonomously in the cold seams. They also use autonomous armored face conveyors. They have self advancing roof supports and other monitoring devices that keep our miners safe. What is common between all of these? They all enable our mining personnel to stay away from potentially hazardous areas. 

Now it is important to note that despite several advances, implementation of fully autonomous systems underground is extremely challenging. This is predominantly due to the lack of GPS systems there. So if you don't have access to GPS signals, you'll have to create your own maps to navigate.

So what are we doing to advance this field? The researchers in academia and industry are looking at so many different topics. So we are researching safe and rapid charging of large format batteries. We are looking at their thermal management. We are also researching autonomous navigation in GPS denied environment. Environment where we have got reduced visibility is extremely challenging and we are looking at that also. We are actively researching human-machine interactions.

So at Penn State I teach a course called EME 440. It is called Energy Systems Automation. It's in the first half of this course. Students learn the math of autonomous system. In the second part of the course students program their own programmable logic controllers.

On the research front we are investigating the impact of thermal runaway using computer models and deep learning models. So we are very confident that our modern mining engineers will continue to play a critical role as mines continue to embrace autonomous systems.

So how many of you are fascinated by the prospect of mining the lunar surface or getting minerals from the asteroids? Of course, these systems have to be truly autonomous. I am confident that many of you are going to adopt this path and lead successful autonomous mining projects in your careers.