STEM-11-HANDOUTS-2024 PDF Ore and Minerals

**LESSON 4: ORES AND MINERALS** Most *metals* are too reactive to exist on their own in the ground. Instead, they exist combined with other elements as compounds called *ores*. Ores are raw materials for making metals**.** *Minerals* are those in which individual crystals are composed of unit cells...

**LESSON 4: ORES AND MINERALS** Most *metals* are too reactive to exist on their own in the ground. Instead, they exist combined with other elements as compounds called *ores*. Ores are raw materials for making metals**.** *Minerals* are those in which individual crystals are composed of unit cells or basic unit layers of two or more types. *Minerals* are inorganic catalysts that function as regulators of metabolic activities in the body. *Ore* is a deposit in Earth's crust of one or more valuable minerals. The most valuable ore deposits contain metals crucial to industry and trade, like copper, gold, and iron. Earth contains a finite amount of ore. Ore genesis, the process by which a deposit of ore is created, is estimated to take millions of years. *There are three major types of ore genesis: internal processes, hydrothermal processes, and surficial processes.* Ore can accumulate through geologic activity, such as when volcanoes bring ore from deep in the planet to the surface. This is called an *internal process*. Ore can also accumulate when seawater circulates through cracks in Earth's crust and deposits minerals in the areas around *hydrothermal vents*. This is called a *hydrothermal process*. Finally, ore can accumulate through processes that take place on the surface of Earth, such as erosion. This type of ore genesis is called a surficial process. *Ore* can also fall to Earth as rocky debris from elsewhere in the solar system. These pieces of debris, entering the atmosphere as shooting stars, are called *meteorites*. Many meteorites contain large amounts of iron ore. *Ore* is a nonrenewable resource. Because modern societies rely so heavily on metallic ore for industry and infrastructure, miners must constantly seek new ore deposits. Mining companies have explored every continent, as well as the ocean floor, in their search for valuable ore. This scarcity contributes to ore\'s value. The process of extracting metal ores buried deep underground is called *mining.* The metal ores are found in the earth's crust in varying abundance. The extraction of metals from ores is what allows us to use the minerals in the ground! Ores are very different from the finished metals that we see in buildings and bridges. They consist of the desired metal compound and the impurities and earthly substances called *gangue.* The extraction of metals and their isolation occurs over a few major steps. - Concentration of Ore - Isolation of metal from concentrated Ore - Purification of the metal *Ore* is a deposit of one or more precious minerals in the Earth's crust. The most important ore deposits, such as copper, silver, and iron, contain metals that are essential to industry and trade. Copper ore is mined for a wide range of industrial applications. *Example of ores includes, include Bauxite (Al), Chalcocite (Cu), Chalcopyrite (Cu), Chromite (Cr), Galena (Pb), Hematite (Fe), Iron Pyrite (Fe), Laterite (Al & Fe), Magnetite (Fe), Psilomelane (Mn), Pyrolusite (Mn), Sphalerite (Zn) & Stibnite (Pb) Etc.* *Metallurgy* is the field of science which deals with the extraction of metals from ores which are naturally found in the environment. Most of the elements, especially metals are presently combined with other elements and these are called *minerals.* *Mineral,* naturally occurring homogeneous solid with a definite chemical composition and a highly ordered atomic arrangement; it is usually formed by inorganic processes. *Minerals* display a highly ordered internal atomic structure that has a regular geometric form. Because of this feature, minerals are classified as crystalline solids. Minerals have been broadly classified into two classes, *primary minerals and secondary minerals*. Minerals which were formed by igneous process that is from the cooling down of the molten materials called magma, have been put in the primary category, while those formed by other processes have been put in the secondary category. Primary minerals which occur in the sand fractions of the soil had not undergone any change. A *primary mineral* is any mineral formed during the original crystallization of the host igneous primary rock and includes the essential mineral used to classify the rock along with any accessory minerals. Primary minerals including K-feldspars (orthoclase, sanidine, and microcline), micas (muscovite, biotite, and phlogopite), and clay-size micas (illite) are widely distributed in most soil types, except in highly weathered and sandy soils. *Secondary minerals* are formed as byproducts of weathering at the Earth\'s surface. The most common secondary minerals are Kaolinite (chemical weathering of Feldspar), Chlorite (weathering of Biotite, Pyroxene, and Amphibole), Sericite (weathering of feldspar), and Serpentine (hydrothermal modification of Olivine). **LESSON 5: FOSSIL FUEL** A *fossil fuel* is a carbon compound- or hydrocarbon-containing material such as coal, oil, and natural gas, formed naturally in the Earth\'s crust from the remains of prehistoric organisms (animals, plants and planktons), a process that occurs within geological formations. Fossil fuels are made of hydrocarbons, they contain *carbon and hydrogen\'s.* The origin of fossil fuels is the *anaerobic decomposition* of buried dead organisms containing organic molecules created by *photosynthetic carbon fixation*. The conversion from these materials to high-carbon fossil fuels typically requires a geological process of millions of years. Due to the length of time, it takes nature to form them, fossil fuels are considered *non-renewable resources*. A *fuel* is a substance that provides a form of energy. Such as heat, light, electricity, or motion. The process of burning a fuel is called *combustion*. The three major fossil fuels are *coal, oil and natural gas.* Coal is a solid fossil fuel formed from plant remains. Known deposits of coal (and other fossil fuels) can be obtained using current technology are called reserves. Coal is the most plentiful fossil fuel in the U.S. and to the other countries. Because It's easy to transport. *It provides lots of energy when burned.* *Oil* is a thick, liquid fossil fuel, it is formed from remains of small animals, algae and protists. Petroleum is another name for oil. The United States consumes about one-third of all the oil produced in the world. When oil is first pumped out of the ground, it is called *crude oil.* A factory where crude oil is separated into fuels and other products by heating is called a *refinery*. The third major fossil fuel is natural gas. t is a mixture of methane and other gases. Advantages: - Provides lots of energy - Lower levels of air pollutants than coal and oil - It's easy to transport. Disadvantage: - Highly flammable Fossil fuel takes hundreds of millions of years to form. Fossil fuels therefore are considered a nonrenewable resource. New resources of energy are needed to replace the decreasing fossil fuel reserves. Natural Gas is a mixture of hydrocarbons, primarily methane. Other gases present typically include ethane, propane, nitrogen, water vapor, and carbon dioxide Liquefied petroleum gas (LPG) 46-51 MJ/kg Natural gas 42-55 MJ/kg. Theory states natural gas is composed of the remnants of decayed plant and animal matter that has been subjected to immense pressure under the earth's crust over millions of years. A further way in which natural gas can be produced is by microorganisms breaking down organic matter and producing methane. Natural gas is made up of a combination of gases, which consists largely of methane (CH4) with lesser amounts of ethane, propane and butane as well as nitrogen, carbon dioxide and traces of some other gases. Natural gas is used to produce steel, glass, paper, clothing, brick, electricity and as an essential raw material for many common products. Some products that use natural gas as a raw material are paints, fertilizer, plastics, antifreeze, dyes, photographic film, medicines, and explosives. Fossil fuels are used to produce energy; in the home they are burned to produce heat, in large power stations they are used to produce electricity and they are also used to power engines. *What Do Fossil Fuels Release When Burned?* - Carbon Dioxide Of all the greenhouse gases, carbon dioxide is the most abundant when it comes to human-related emissions. Carbon dioxide is released in large quantities from burning coal, gas, and oil because these fuels are primarily composed of hydrocarbons released in the form of carbon dioxide once combusted. - Carbon monoxide is released when carbon-based fuel is not completely burned. The primary source of carbon monoxide emissions comes from road vehicles. Non-road vehicles, like boats or construction equipment, also contribute to carbon monoxide emissions. - Sulfur dioxide is found in coal and oil. It can be emitted when these fossil fuels are burned and through the process of extracting gasoline from crude oil. - Nitrogen oxides are released when fossil fuels are burned at high temperatures in motor vehicles or from other fuel-burning sources in industrial or home settings. Nitrogen dioxide, one common form of nitrogen oxide, creates smog over city centers. - Lead used to be a more common emission when leaded gasoline was used for vehicles. Today, most lead pollutants can be found in the air around factories that separate metal from ore. - Particulate Matter is any solid particle or liquid droplet found in the air. Particulate matter is released when fossil fuels are burned and can be found in higher concentrations in regions that burn more fuels, like city centers or power facilities. **Environmental Problems of Fossil Fuels** There are three main adverse effects of burning fossil fuels: air pollution, water pollution, and climate change. These effects are caused by the products released when fossil fuels are burned. - Air pollution occurs when products like sulfur dioxide, carbon monoxide, nitrogen oxides, and particulate matter are released from burning fossil fuels. Air pollution has been found to cause respiratory disease, cardiovascular disease, and cancer. - Water pollution occurs when sulfur dioxide dissolves into water and creates sulfuric acid. This produces acid rain and can lead to the acidification of freshwater sources like lakes and streams. When these bodies of water become too acidic, life cannot survive in them. Acid rain can also affect local crops and soil acidity levels. - Climate change is a significant threat to ecosystems and human populations worldwide. Carbon dioxide emitted through burning fossil fuels plays a huge role in global warming. As more carbon dioxide is released into the atmosphere, more heat is trapped on earth through the greenhouse effect. **LESSON 6: BIOMASS** *Biomass* is stored sunlight energy from plants that can be converted into electricity, fuel, and heat through various processes. It is a renewable resource found worldwide. *Biomass* can be combusted to generate electricity and heat, anaerobically digested to produce biogas, fermented to create biofuels like ethanol, or mechanically processed into biodiesel. These biomass conversion processes produce primary products like electricity, heat, biogas, or biofuels, as well as secondary products like *fertilizer or chemicals.* **TYPES OF BIOMASS** - WOOD AND AGRICULTURAL PRODUCTS Most biomass used today is home grown energy. Wood logs, chips, bark, and sawdust accounts for about 44 percent of biomass energy. But any organic matter can produce biomass energy. Other biomass sources can include agricultural waste products like fruit pits and corncobs - SOLID WASTE/ LANDFILL GAS AND BIOGAS Burning trash turns waste into a usable form of energy. One ton (2,000 pounds) of garbage contains about as much heat energy as 500 pounds of coal. Garbage is not all biomass; perhaps half of its energy content comes from plastics, which are made from petroleum and natural gas - LANDFILL AND GAS AND BIOGAS Bacteria and fungi are not picky eaters. They eat dead plants and animals, causing them to rot or decay. A fungus on a rotting log is converting cellulose to sugars to feed itself. Although this process is slowed in a land­ a substance called methane gas is still produced as the waste decays. - ETHANOL is an alcohol fuel (ethyl alcohol) made by fermenting the sugars and starches found in plants and then distilling them. Any organic material containing cellulose, starch, or sugar can be made into ethanol. The majority of the ethanol produced in the United States comes from corn. New technologies are producing ethanol from cellulose in woody ­bers from trees, grasses, and crop residues. - BIODIESEL is a fuel made by chemically reacting alcohol with vegetable oils, animal fats, or greases, such as recycled restaurant grease. Most biodiesel today is made from soybean oil. Biodiesel is most often blended with petroleum diesel in ratios of two percent (B2), ­percent (B5), or 20 percent (B20). It can also be used as neat (pure) biodiesel (B100). Biodiesel fuels are compatible with and can be used in unbodied diesel engines with the existing fueling infrastructure. **Possible Applications of Biomass** - Bioenergy production; - Biochemicals; - Organic / lignocellulosic disposal. **Advantages of Biomass** - Energy and environmental self-sustainability; - Obtaining high added value products; - Total conversion of biomass without processing waste; - Possibility of renewing traditional industrial sites currently being abandoned or in partial use of nominal production capacities. **Disadvantages of Biomass** - Biomass energy is not as efficient as fossil fuels - It is not entirely clean - Can lead to deforestation. - Biomass plants require a lot of space.