Lesson 2: How Ore Minerals Are Found, Mined, and Processed for Human Use PDF

How Ore Minerals are Found, Lesson Mined and Processed for 2 Human Use What’s In In lesson 1, we have learned the list of important minerals in the society and its significant used in our lives. We also begin to appreciate its critical role in making advancement...

How Ore Minerals are Found, Lesson Mined and Processed for 2 Human Use What’s In In lesson 1, we have learned the list of important minerals in the society and its significant used in our lives. We also begin to appreciate its critical role in making advancements in various areas of the society. The developments made in the field of information technology, modern medicine, agriculture, commerce, jewellery, industries and many others have created a wonderful influence on the country’s economy. With the various benefit that these minerals have given, one could not help himself thinking of how comfortable life is at present. However, the information on how ore minerals are found, mined and processed are still vague thus, it will be discussed for us in this lesson. What I Need to Know Inside the Earth’s crust are ore deposits containing minerals of great economic advantage. Ore minerals such as bauxite, rutile, hematite, pentlandite and chalcopyrite are the sources of our most important metals. Aluminum, a metal that is used in aluminum foil, in medicine containers and other products, is extracted from an ore called bauxite. Copper which is used as electrical wire because it is an excellent conductor of electricity, is taken- out from ore called chalcopyrite. Titanium, the strongest metal that is used in aircraft, armor plating, naval ships, spacecraft and missiles is extracted from an ore rutile. With this information, the intelligent Tao is driven by his quest to find the exact depot of these materials. Though there are many resources that have helped him improved his ways of living, his future depends on the way these ore minerals are mined, processed and used. Have you ever visited a mine or a place where ore minerals are processed? What do you think you will do when you find a rock- containing ore during a mountain trip with your friends? Will you rushed directly to a nearby processing plant for this ore to be checked and analyzed? In this lesson you will be learning some facts about mining and processing these ore minerals from rocks. Thus, at the end of the lesson you are expected to discuss and explain how these ores are found, mined, and processed for human use. However, before we will mine deeper, you need to answer the first activity. Remember that you are a mining engineer in the making. Have fun.  What’s New Activity 1: Situational Simulation You need at least three people from your community who have experienced working in a mining site or in the gold-buying business. In this situation, you need to ask these questions; 1. How long have you been working in the mining site? 2. Can you share the standard operating procedure (SOP) that you have been doing in the work place? 3. What are the responsibilities you are performing in the working area? 4. What are your experiences inside the work place? 5. If given a chance to choose a job, what do you think is the job that you will choose? Why? You can tap assistance from your parents or family members to accomplish this task. Break a leg! What Is It Ores are natural rocks or sediments that hold one or more valuable minerals, mostly metals, that can be mined, processed and sold at a great price (Thalhammer 2008, 10). They are contained inside the Earth in a limited quantity because its creation and deposition would take millions of years. Ore genesis, the process by which a deposit of ore is created has three major types: internal processes, hydrothermal processes, and surficial processes. Internal processes include geologic activity such as when volcanoes bring ore from deep in the planet to the surface. Hydrothermal process happens when seawater circulates through cracks in Earth’s crust and deposits minerals in the areas around hydrothermal vents. Hydrothermal vents are cracks on the seafloor where seawater meets magma. Finally, ore can accumulate through processes that happen on the surface of Earth, like erosion. This type of ore genesis is referred to as surficial process (Evans 1993, 403) Aside from ore genesis, ore minerals can also be deposited to the Earth because of the rocky fragments or debris from the solar system that fall. These pieces of fragments, that enter the Earth’s atmosphere are called meteorites or what we known as “shooting stars”. Countless meteorites contain large amounts of iron ore where we could extract metallic iron for industry and infrastructure purposes. Moreover, ore minerals can be found in the Earth's surface or to its crust and at the ocean floor. Quarts, mica and olivine are some of the silicate rocks that are frequently found on the surface of the Earth. Likewise, igneous rocks (granite, gabbro and basalt), metamorphic rocks (gneiss, schist and amphibolite) and sedimentary rocks (sandstone, shale, and limestone) can also be found on the Earth’s crust (Williams 2013, 3). In the ocean floor or the “seabed”, the presence of various ore minerals can also be found since the ocean floor itself is made up of crystallized matter from silicate magma known as mafic rocks. Moreover, numerous Volcanic Massive Sulfide (VMS) deposits can be observed in the ocean floor which are rich in ore that can be mined for its resources. Minerals found under the seabed include gabbro, basalt, serpentine, peridotite, olivine and ore minerals from Volcanic Massive Sulfide deposits. Franklin, J.M.; Sangster, D.M.; Lydon, J.W.; 1981,485-627) Now that we have learned new inputs, let us try to answer the activity below. What’s More Activity 2: Getting to Know MOre Minerals! Direction: Fill in the needed information below. You can mine information from the concepts discussed above. What Are Ores and Where to Find These Minerals Ores are: ________________________________________________________________ How ore mineral deposits are created? 1. 2. 3. 4. Where can we find these ore minerals? Ocean Floor 1. 1. 2. 2. 3. 3. 4. 4.  What Is It Ore is a nonrenewable resource and since modern societies rely so much on its use in infrastructure and industry, miners need to find new ore deposits to withstand its increasing demand. With this, mining enthusiasts have trekked every part of the world and even explore the ocean’s depth, in search for these ores. Mining is the process of extracting the valuable materials from the Earth. In the Philippines, mining is a growing and promising industry. According to the Mines and Geosciences Bureau’s (MGB) Mining Facts and Figures, our country is acknowledged as the largest copper-gold deposits of the world and the fifth mineral-rich country of the world for gold, copper, nickel and chromite. In 2018, our country was the world’s second-largest producer of nickel ore and sold most of its output to its top buyer China. The Northern Central and Southern part of Mindanao were identified as rich in chromium, copper and gold deposits. Also, there are about 40 metallic mines and 62 non-metallic mines operating in the Philippines, however, only 1.4% of these were covered by mining permits according to the 2016 record of the bureau. These mining companies have used the two main mining methods; surface mining and underground mining. In surface mining, minerals are extracted near the Earth’s surface. This includes six (6) processes; strip mining, placer mining, mountain top, hydraulic mining, dredging and open pit. In an underground mining, ores are taken out from the ground by digging. This includes five (5) processes; slope mining, hard-rock, drift mining, shaft and bore-hole process. These mining techniques have unearthed a lot of mineral deposits from the Earth and have given man countless benefits. A fact that an ore is always mixed with unwanted rocks and minerals known as gangue, these two can still be separated by mechanical or manual processes (Hassan 2010,2). Metallurgy is a process used to extract metals in their pure form. A substance called flux is added to remove the gangue (impurities). There are classifications under the metallurgical process. The first process in metallurgy is crushing and grinding of ores into a fine powder (pulverization) in a crusher or ball mill. Second process is called ore dressing or the process of removing impurities from ore. Third is doing the hydrolytic method wherein ores are poured over a sloping, vibrating corrugated table with grooves of which a jet water flowed over the surface. This allows the denser particles to settle in the grooves and washed away the impurities. Fourth is to do magnetic separation in which the crushed ore is placed on a conveyor belt with two wheels. One of the wheels is magnetic and therefore attracts magnetic particles and those non-magnetic particles just fall apart. The fifth classification is called froth floatation in which the crushed ore are placed in a large tank that contains oil and water, then a current of compressed air will passed through to wet the ore and separates the impurities in the form of froth. Because the ore is lighter, it floats and left the impurities behind. Roasting and calcination is the last method in which a concentrated ore is heated in the presence of oxygen (roasting) and is usually applied to sulfide ores. For ores containing carbonate or hydrated oxides, heating is done in the absence of air to melt the ores, and this process is known as calcination. Chalcocite, galena and sphalerite and other metals combined with sulfur were exposed to this process to yield copper, zinc and iron (Gill 2018, 1-5) After all these processes utilization follows. Man, further purified or mixed these metals with other metals like what happened in a copper refinery or steel mill. Others are utilized by people in jewellery business using the gold ores. Majority of these gold ores were converted into jewelry and only small percentages were processed into electronic equipment, coins and dental fillings. Likewise, since these ore minerals generate valuable metals, they were considered a big help in infrastructure, trade and industry that in turn have boosted the country’s economic health status in the world. What’s New Activity 3: Let’s Do SEE-quencing of Thoughts Direction: The sentences below are disorganized and it is all about the principles of metallurgy. Use the numbers 1-6 to arrange the process in chronological order. To tickle the brain neurons, the first one is done for you. __ Ores are heated using oxygen in the case of sulfide ores and heated in the absence of oxygen for ores containing carbonates or hydrated oxides. ___ The crushed ore is placed on a conveyor belt with two wheels; one of which is magnetic to attract magnetic particles and those non-magnetic ones will fall apart. _1_ The extracted ores are pulverized in a crusher or ball mill. ___ The crushed ores are placed in a large tank that contains oil and water that makes the ore floats and separates impurities in the form of froth. ___ Impurities from the ores are removed. ___ The ores are poured over a sloping, vibrating corrugated table with grooves of which a jet water flowed over the surface to wash away the impurities. The denser particles settle in the grooves.  What Is It There are five (5) existing mining sites in Region X as published by Mindanao Journal of Science and Technology (Vol.13,2015). These mining places are situated at Gango, Libona, in Bukidnon, Barangay Tumpagon and Barangay Pigsag-an in Cagayan de Oro City, Nangcaon, Opol, in Misamis Oriental, and Rogongon, Iligan City. The miners in these sites have use various methods in mining. Tunneling, panning /gold washing, flushing, panning and flushing were used. In the tunneling method, underground excavations are made to get the mineral ore. Panning, in mining, is a simple method of separating gold from soil or gravels by washing in a pan with water. In flushing method, crushed rocks are exposed to a high velocity water to removed impurities and obtained the valuable element. Other miners used combination methods with the hope of increasing yield. Miners from Gango, Libona in Bukidnon have practiced the tunneling method since the mining location is not near the river system and the area’s geography ranges from flat to very steep hills. Mining site that are located along the river system have practiced gold panning methods like Barangay Nangcaon, Pigsag-an, Tumpagon, and Rogongon Veteran gold miners and the local folks generally used gold panning method as a manual technique of separating gold from other materials. With this technique, the ground materials continue to pollute the river system specially the Iponan River ecosystem with depositions of high loads of sediments that have shallow the river beds and poses threat to other aquatic life since siltation lessen sunlight dispersion, water temperature and water habitat productivity. Also, majority of the miner-respondents practiced indigenous ways in their purification method. Fifty-seven percent (57%) of the miners in Gango, Libona have used leaves (tuog), soap, water and vinegar. The use of mercury in their mining activities is strictly forbidden yet there are few miners who opted to use mercury in their mining activities. For the other mining sites (other than Gang, Libona, Bukidnono), the use of water and bilingan or panning were commonly used as strainer to removed impurities (Palmes et al. 2015,75- 98). Moreover, other mining companies in Mindanao are using extensively the leaching process because they believed that it is more convenient to do, needs less energy and less harmful because there are no gaseous emissions involved in the process. In this process, the ore is treated with chemicals (cyanide, ammonia, alkali and acid) to convert the valuable metals within into soluble salts while impurity remain insoluble. Then, it can then be washed out and processed to get the pure metal and leave the tailings (material left over). However, excessive leaching releases harmful chemicals to the water sources that may affect the communities’ drinking water. There are four types of leaching: cyanide leaching (gold ore), ammonia leaching (crushed ore), alkali leaching (bauxite ore) and acid leaching (sulfide ore). Additionally, a method called electrolysis uses electricity and acid to separate metal from the ore. A metal like aluminum is extracted from bauxite by electrolysis. In this manner, bauxite is placed in a pool of acid and run through it an electrical current leaving aluminum in the process. Since mining industry is a promising business in the Philippines, the government has imposed laws and stipulated in the Republic Act (R.A.) No. 7942, generally acknowledged as the "Philippine Mining Act of 1995. This act has given benefit to both the government and the contractor. Health and safety measures for everyone have been given priorities for the success of the mining industry relies to this protocol. Moreover, mining knowhow and safety habits have been advanced by innovative companies and were encouraged by governmental legislation (Glover and Morse 2000, 18).  In connection with this, biomining was introduced in the mining business wherein special bacteria, prokaryotes and fungi are used to mine valuable metals from ore minerals without drilling and blasting of rocks (Aggangan 2018, 1). What’s New Activity 4: Concept Mining Direction: Complete the concept map on types of mining using the information above. You need keen eyesight in this mining activity. Enjoy! Activity 4A: Word Power Direction: Give the definition of the italized words given below. Definition: Leaching _________________________________ _________________________________ Definition: _________________________________ _________________________________ Metallurgy