Design Life-Cycle
assess.design.(don't)consume
Jenny Wong
Professor Codgell
DES040A Section 2
1 December 2019
Ceramic Magnets- Materials
Ceramic magnets, also known as ferrite magnets, are a type of permanent magnets that are readily available for people to buy and factories to used. Ceramic magnet material was first created in the 1950s and then further developed into a less expensive alternative to other types of magnet materials in the 1960s (“Ceramic (Ferrite) Magnet Material Overview”). These magnets are a charcoal gray color and they usually come in the form of discs, rings, blocks, and cylinders. They don’t need to be maintained and they do not demagnetize easily, although it is possible; it can take a magnet approximately 700 years to lose half its strength (Gupta). Due to their corrosion and demagnetization resistance and their low cost alternative to metallic metals, they have won wide acceptance. Ceramic magnets represent more than half of the world’s magnet consumption and are usually used for magnetic assemblies designed for lifting, holding, retrieving and separating. Throughout the life cycle of ceramic magnets, although they are only made up of two raw materials, there are several other materials that go into the production process, transportation process, and recycling and waste management.
The two raw materials that are used to make ceramic magnets are iron oxide and strontium carbonate. Iron oxides are naturally occurring pigments that are found in soil and derived from hematite, ranging in colors of black, yellow, red and brown (“Iron oxides”). However, commercial forms are produced synthetically and they impart pastel shades instead of some of the brighter and cleaner shades imparted by other colors (“Iron oxides”). Iron oxides usually form through a solution from ferrous ions, which are released from Fe(II)-bearing silicates and sulfide minerals through weathering (“Iron Oxides” ScienceDirect). After they are formed, the mineral phase, composition, and distribution of iron oxides can be continually altered with the modification of their environments, meaning the formation and transformation phase depends on the environmental conditions under which they have formed (“Iron Oxides” ScienceDirect). The second material, strontium carbonate, is a fine, white powder that can be found in nature as the mineral strontianite, which is one of the main sources to get strontium (“Strontium Carbonate- Material Information”). Strontium is one of the most abundant elements in the earth’s crust and it is found in celestite and strontianite, the only two minerals that contain sufficient amounts of strontium to allow recovery to be possible (“Strontium”). These minerals are found mainly in sedimentary rocks (“Strontium”). Barium can be substituted for strontium, however, the barium composite will reduce maximum operating temperature compared to strontium composites (Singerling). Celestite is a pale sky-blue color that was first discovered in a deposit called the Sakoany deposit by a cattle herder who found some weathered out crystals close to the shore of the bay (“Celestite from Madagascar”). Celestite crystals usually form in cavities in sandstone or limestone and as geodes (“Celestite-Mineral and Healing Properties”). It is commonly found in Sicily, associated with sulfur and in red, cloudy crystals near Toronto, Canada (“Celestite from Madagascar”). The best celestite crystals in the world can be found in Madagascar (“Celestite from Madagascar”). China is the biggest miner of the world’s earth ores needed for most magnets, mining over 55% (“Overview on the World’s Magnet Supply”). After the two raw materials are collected, then the production process can begin.
There are many steps that go into the production of ceramic magnets and each step makes use of different kinds of materials. The production of ceramic magnets begins by calcining a finely, powdered mixture of iron oxide and strontium carbonate to produce a metallic oxide material (“Ceramic Magnets Manufacturing Method.” Dura Magnetics, Inc). Sometimes, other chemical materials such as cobalt and lanthanum will be added to improve the magnetic performance. Then, the fine powder is put through a multiple stage milling operation that uses high pressure nitrogen to reduce the calcined material to a small particle size (“Equipment detail”). The powder is then pre-sintered–either compacted in a die by mixing with water to form slurry or it is machined from isostatically pressed blocks (“Equipment detail”). Most ferrite manufacturers purchase pre-sintered powder directly now. The pre-sintered material will then go through a crushing process with a ball mill equipment that uses steel ball and water in order to become fine powder (“The Manufacture Process of Ferrite Magnets”). While magnetic force is being applied, the powder will then be pressed from the top and bottom with hydraulic or mechanical rams (“Magnet”). Some shapes can also be made by putting the powdered material in a flexible, air-tight, evacuated container and using liquid or gas pressure to press it into shape (“Magnet”). When the sintered process takes place, pre-sintered powder can be used as the raw material of the sintered magnet (“The Manufacture Process of Ferrite Magnets”). In the cutting process of ferrite magnet, because the ferrite is insulating materials, the manufacturer will use a grinding wheel to cut the magnets (“The Manufacture Process of Ferrite Magnets”). To make the magnets have a magnetic force, the pieces needs to use a very powerful electromagnet and they need to be placed between the poles in the desired direction of magnetization (“Magnet”). After the production process is done, the magnets are distributed and transported.
In the distribution and transportation stages, magnets are packaged and shipped using certain methods because of their strong, magnetic force. China supplies most of the raw materials needed in the production of ceramic magnets, so ships are used to carry supplies overseas to other countries. Ships run on bunker fuel, which is made from the refined process of crude oil (Gallucci). Crude oil was formed from the remains of dead, tiny sea animals and plants that pile up on the bottom of the seafloor and mix with mud, eventually forming into crude oil with increased pressure and temperature (“The formation of Petroleum/Crude Oil”). Bunker fuel also contains a lot of sulfur, which is obtained nowadays by having sulfur production go through industrial processes and starting as a by-product (“Sulfur Mining & Processing: What To Know”). When magnets are done being produced, they need to be packaged in specific ways before getting transported in order to keep them from attaching to steel objects. Depending on the size of magnets, different materials are needed to package them correctly. Quarter-sized or smaller magnets are usually put attracting in rows and are wrapped in corrosion inhibiting paper, which uses chloride and sulfuric oxide to accelerate the corrosion rate to protect metals (Rudman). Sometimes, the magnets may also need plastic spacers to stick in between each other in order to reduce the attractive force of other magnets or steel (“Ceramic Magnet Handling and Storage”). The raw materials in plastics come from natural, organic materials such as cellulose, coal, natural gas, salt and, of course, crude oil (“How Plastics Are Made”). Magnets up to 2″ square are arranged in rows with sizable spacers between each magnet or individually wrapped in foam (“Ceramic Magnet Handling and Storage”). Originally, foam rubber was made from natural latex, which is a white sap produced from rubber trees, but today, foam products commonly use the material, polyurethane (“Foam Rubber”). Smaller quantities of large magnets need to go into an appropriate cardboard box, but larger volumes specifically need to be packaged in wooden crates (“Ceramic Magnet Handling and Storage”). The finished product of magnets are preferably shipped by ground transportation. The raw material used for the production of gasoline is crude oil or petroleum, which can be gathered from drilling underground in wells or reservoirs (“Gasoline”). Although it is not recommended, it is possible for magnets to be shipped via air, they just have to be properly packed to block their magnetism. In the packaging process, magnets can be covered with specially designed covers, such as padding or cardboard shredding, or by creating a steel lined box (Hardison). Materials that are used during plane shipping are jet fuel and gas. Jet fuels are primarily derived from crude oil, but can also originate from an organic material found in shale, called kerogen or petroleum solids (Jet fuels JP-4 and JP-7). From the production process to the transportation process of magnets, a lot of waste is produced, so how it gets recycled and managed becomes a matter to consider.
To manage wastes from the production of ceramic magnets, recycling methods are created to recover the valuable rare-earth material from manufacturing waste. When magnets reach the end of their life, they are thrown away with a lot of valuable metals they contain that can actually be recovered. During the manufacturing of magnets, the grinding and cutting processes produce waste metal powders and filings, called swarf, which contains reusable rare-earth materials like samarium, neodymium, and dysprosium (“New process recycles magnets from factory floor”). Samarium-cobalt waste powders are reused as raw material to create polymer-bonded magnets that work similarly as well as commercial bonded magnets that are made from new materials (“New process recycles magnets from factory floor”). The waste powders can also be used to make sintered magnets. Dysprosium and neodymium are recovered using a solvent extraction method. First, magnets get oxidized and roasted at high temperatures (more than 500 °C); then they go through acid leaching, using strong acid like sulfuric acid (Yoon, Ho- Sung, et al.). Afterwards, an alkali treatment leads to double-salt precipitation, which is further leached in hydrochloric acid and then the final leach liquor is prepared (Yoon, Ho- Sung, et al.). In the solvent extraction processing, numerous extractants, including macrocyclic ligands, pyrazolones, organophosphorus extractants, and P-based extractants were used for extraction and separation studies of dysprosium and neodymium (Yoon, Ho- Sung, et al.). Neutral organophosphorus extractants such as TBP, TOPO, and others in HDBP, Cyanex 302, and Cyanex 272 were specifically used as synergists in a synergistic solvent extraction process (Yoon, Ho- Sung, et al.). Various diluents, such as kerosene, benzene, toluene, xylene, and carbon tetrachloride, were used as organic phase media and kerosene was mainly applied in many studies of the rare earth materials’ extraction, separation, and synergis-tic solvent extraction processes (Yoon, Ho- Sung, et al.). Something to be concerned about is that this material recycling method is using huge amounts of hazardous mineral acids that produce toxic fumes, which are harmful to the environment (Millsaps). Researchers at the Critical Materials Institute (CMI) came up with a new rare-earth material recycling process that manufacturers can use, which is to dissolve magnets in an acid-free solution (Millsaps). The recycled wastes and wastes produced are part of the life cycle of ceramic magnets.
In conclusion, the life cycle of ceramic magnets include and use a lot more materials than it seems, compared to the actual product. Although there are only two raw materials that make up ceramic magnets, several other materials contribute to the production process, transportation process, and recycling and waste management as well. Materials such as added chemicals, nitrogen, isostatically pressed blocks, corrosion inhibiting paper, plastic spacers, and foam are all used in the production and packaging process of the magnets. When the raw materials and the product of the magnets are transported, different types of fuels that include crude oil are used. Furthermore, ceramic magnets are made using a lot of rare-earth materials that can actually be recovered, however, manufacturers are very dependent on toxic mineral acids as a resource for the extraction and separation of the rare-earth materials. All of these materials demonstrate that even products as simple as ceramic magnets can have a complex life cycle.
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Lilliana Paglia
Group: Shaina Whaley and Jenny Wong
Professor Cogdell
Des 40A Section 2
4 December 2019
Life Cycle of Ceramic Magnets - Embodied Energy
Ceramic magnets are one of the world’s most popular types of magnets on the market. These magnets are incredibly versatile as they are used in small scale products such as refrigerator magnets and even large scale items such as car engines. Since the internal structure of a ceramic magnet can generate its own magnetic field, it can be classified as a type of permanent magnet (Hannahs). Based on their material composition of iron and strontium carbonate, ceramic magnets can also be defined as hard ferrite magnets. Most ceramic magnets are inexpensive, yet have high coercivity. Because of their cost, ceramic magnets are used in various household items we see in our everyday lives such as in our office supplies or in the toys we give to children. However, because these magnets are also high in magnetization and very resistant to demagnetization, they have been used in more industrial settings such as engines and other appliances as well. Ceramic magnets have a simple design of only two raw materials, making the manufacturing process faster and more cost efficient than other magnets. However, like all magnets, they need to go through a series of both physical and chemical processes in large manufacturing facilities that consume high energy before they can reach stores across the world. Ceramic magnets are favored for their low cost and high resistance to corrosion and demagnetization, yet use large quantities of energy during the material extraction, manufacturing, and waste removal processes.
The number of raw materials that go into a ceramic magnet may be limited; however, the process of extracting these materials is very energy intensive. The two main raw materials that go into the creation of ceramic magnets is iron and some type of metal, most commonly strontium carbonate. China is the largest supplier of these raw materials in addition to having the largest number of ferrite magnet manufacturing plants and consumers. There is little iron mining that occurs in the US and the main sources of strontium deposits are found in China, Russia, and Brazil. Strontium has not been mined in the US since 1959. The largest strontium deposit is the Dafenshan strontium deposit located in the central Qaidam Basin with a reserve of about 18 million tons (“China Exploits Largest Strontium Deposit”). This basin runs on oil and natural gas. As of September 2019, it was recorded that China mined 77.37 million metric tons of iron ore (“China: Iron Ore Mining by Month 2019”). Major energy sources for iron mining include purchased electric energy and fuel oil. In 1992, the total amount of iron ore mining in the world had consumed 62.3 trillion Btu, which is about 18.2 billion kwh and mining has only increased since then. During the mining process, front-end loaders use the most energy along with dump trucks, bulldozers and bulk trucks. These machines use kinetic energy inorder to do the heavy lifting and moving of materials. Also, chemical energy is used inorder for the engines of these machines to use fuel. Throughout the entire extraction process, these machines contribute to consuming about 84 percent of the total energy per ton and most run on diesel fuel. Hauling and loading are responsible for the highest amount of greenhouse gas emissions during the mining process as well (“Energy and Environmental Profile of the U.S. Mining Industry - Iron”). As for crushing and grinding the materials, a ball mill is used which runs on electric energy. The ball mill relies on kinetic energy in order to crush the raw materials and get the powders ready for manufacturing and formulation. In total, the process of iron ore mining alone uses 32.2 TJ of energy or about 9 million kwh, this includes energy from coal, petroleum, natural gas, and non-fossil electricity (“Economic Input-Output Life Cycle Assessment (EIO-LCA) US 2002 (428 Sectors) Producer Model”). After being extracted from the earth, the raw materials are transported to manufacturing facilities.
The process of making ceramic magnets requires high energy consuming heavy machinery from start to finish. For a more visual representation of the production process see the flowchart in Figure 1. The manufacturing process begins with combining the raw materials into a mixture of 80% iron oxide and 20% strontium carbonate (“Hard Ferrite Magnets”). The mixing step requires chemical energy as iron oxide is combined with strontium carbonate and crystal growth inhibitors then pre sintered at high temperatures. Sintering is the process of taking iron rich materials along with fuel such as coke breeze and fine coal, and other additives, and turning it into a porous material that is ready for blast furnaces. These machines use high temperatures of heat ranging from 900 - 1400 degrees celsius (Wang). Process heating is one of the largest energy consumers in a manufacturing facility (“Manufacturing Facilities”). After going through the blast furnace, kinetic energy is used in a conveyor belt that moves materials along to the next machines where the mixture undergoes a milling process before being moved into the wet pressing stage. The mixture enters the wet pressing machine in the form of a slurry (“Ceramic Magnets Info”). The machine runs on electricity and uses pressure to press the slurry into a magnetic field. The pressed mixture is then cut into different shapes using a tool die set. Most of these machines are powered by electricity and are constantly running in the factory. In some manufacturing facilities there are machines that can’t be turned off but rather set to a lower level which can consume greater amounts of energy overtime. In the past decade, most manufacturing facilities have been moving to China because of the cheap labor and close proximity to raw materials (“Ferrite Magnet Powder Manufacturing Plant Project Report 2015”). This location has allowed for greater production of magnets to meet demands; however, increased the mileage and energy cost of transporting these goods.
The largest provider of energy for the distribution and transportation of ceramic magnets is fossil fuels. Because of their widespread use in various products and industries around the world, ceramic magnets have to be transported across long distances. There are a select number of ferrite magnet manufacturers and suppliers in the US such as Integrated Magnetics located in Culver City, CA (“Ferrite Magnets Manufacturers, Suppliers and Industry Information”). These facilities ship their products through ground shipping using trucks that run on petroleum. The energy equivalent of about 1 gallon of fuel used by one of these trucks is equivalent to 33.7 kwh. In order to store the magnets in warehouses and load them onto trucks, material handling equipment is used. Some of the energy for loading onto trucks include human energy; however, a majority is kinetic, chemical and electrical energy used by heavy machinery. A common vehicle used in warehouses is the forklift. Forklifts run on an internal combustion engine that uses fuels such as gasoline, diesel fuel, liquid petroleum gas, and compressed natural gas (“Powered Industrial Trucks ETool: Types & Fundamentals - Power Sources: Internal Combustion”). Most magnet manufacturers refrain from shipping by airplane because of the magnetic field produced by the magnets that may hinder the functionality of the aircraft. However, if packed correctly where maximum field strength of the magnets is less than 7 feet, airplanes can be used which run on jet fuel (Hardison). Since the raw materials of ceramic magnets are mainly extracted in China, the number of manufacturing plants in China has increased which has saved costs for transportation. However, there are still tons of materials that need to travel across oceans to be manufactured in other countries such as the US. Both ground shipping and freight ships are used to transport raw materials. The greatest amount of iron transported internationally is by water which ranges at about 20,100 tons per kilometer (“Economic Input-Output Life Cycle Assessment (EIO-LCA) US 2002 (428 Sectors) Producer Model”). Large freight ships or cargo ships currently use a thick type of oil known as bunker fuel in order to transport such heavy loads across long distances. Reports have shown that these ships may use diesel fuel by 2020 (Ronan). For transporting fully manufactured magnets that contain a magnetic field, certain guidelines need to be followed such as the orientation of the magnets and the distance between each. These rules allow for easy travel especially during ground shipping where the inside of the trucks are made of steel. The magnets’ strong magnetization is not favored during transportation, however, it is a beneficial aspect to recycling.
Magnets play a key role in the process of separating and sorting different metals during the recycling process, yet the magnets themselves cannot be recycled or broken down. Ceramic magnets are quite reliable during their use; however, magnets themselves have no energy (Jensen). Moving magnets and placing them in locations where one may want to use them takes kinetic energy. If the ferrite magnets are used in engines, kinetic energy is used to move the magnetic fields which can generate electric energy (“Electricity Explained - Magnets and Electricity”). However, the act of magnetism and having a magnet be attracted to another is a force and not a type of energy (Jensen). As for recycling, a complete ceramic magnet that has gone through the entire manufacturing process cannot be broken down and used to create other products or items. However, throughout the manufacturing process, ferrite powders and residues from the raw materials can be collected and recycled. These recycled materials can be used in the same manufacturing facilities to produce ferrite magnets with the same coercivity as the magnets made from the original raw materials. Some studies have shown that not only can the recycled materials match the coercivity of other ferrite magnets, but can exceed them with a 3.5 times larger coercivity value (Bollero). Since the powders are recycled and used in the same facilities, the manufacturers are saving money and energy because they do not have to transport the materials to a separate location. Although magnets in their final form are unable to be recycled, they are very resistant to demagnetization and have a long lifespan. Unlike other products that may waste energy by maintaining or buying new parts for, ceramic magnets will maintain their quality. However, when these magnets are disposed of they will most likely sit in a landfill which requires no energy. It is possible for the magnet to be demagnetized using a very strong magnetic field. The demagnetizer will heat a magnet past its curie point which will free the magnetic dipoles from their ordered orientation (“Demagnetization”). An average demagnetizer runs on electricity, and converts the energy into heat. During waste removal, metals are shredded and then melted (LeBlanc). Melting takes place in a large furnace that is either powered by electricity, natural gas, or fuel oil, and converts this energy into heat. Overall, the amount of energy used during a ceramic magnet’s lifecycle is highest during manufacturing and lowest during use.
After analyzing the energy life cycle of ceramic magnets, it is evident that the energy consumption of the extraction of raw materials and the manufacturing process stand out overall. Although a majority of the mining of raw materials is occuring overseas in China, we should still be aware of how much energy is being used in order to meet demands for manufacturing products. With the various new technologies being invented, demands for these magnets will only increase, for instance in products such as hybrid and electric cars. Ferrite magnets are predicted to play a significant role in green energy technologies of the future. Permanent magnets are being used in the motors of hybrid and electric cars, which help to decrease the amount of CO2 emissions in the air compared to current vehicles that run on petroleum. The increasing use of these magnets in car engines will help decrease the use of fossil fuels in vehicles; however, an increase of fossil fuels will be needed in order to increase the production of magnets to meet new demands. With an increase in demand comes an increase in the number of manufacturing facilities, especially in China where these companies take advantage of local raw materials and cheap labor. It is important to know how much energy goes into making ceramic magnets because although ceramic magnets will contribute to greener technologies, they will still contribute to high energy manufacturing and the use of fossil fuels.
Figure 1
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Magnetic Products,
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Shaina Whaley
Lilliana Paglia, Jenny Wong
DES 40A
Professor Cogdell
Ceramic (Ferrite) Magnet Waste
Permanent magnets are magnets where the magnetic field is generated by its internal structure. There are different types of permanent magnets; ceramic (sometimes called ferrite) magnets are the most abundant on the market for their low cost and anti-corrosion and demagnetization qualities (“What Are Ceramic Magnets and How Are They Made”). This means that they can be used almost anywhere within any material and last longer than the application they are used in and they do not lose their magnetization. They are typically used in computer hard drives, microphones, speaker systems, and motors. Ceramic magnets are made out of two basic materials: iron oxide and strontium carbonate. Even though they are composed of only two materials, the life cycle is an extensive energy filled and waste polluted process. The life cycle of ceramic magnets through the raw material acquisition, transportation, distribution, and manufacturing produces solid, airborne, and waterborne wastes which causes environmental concerns, though as far as recycling is concerned there are new ways the magnets and the byproducts are being put back into the production process.
The raw materials acquisition phase of the life cycle is arguably the most detrimental to the environment out of all the phases. The iron oxide and strontium carbonate (called strontianite in its natural form) have to be mined from the earth. Mining is an extremely damaging process and causes water contamination, both surface water and groundwater, from the surface runoff of the waste rock and tailings (Lu). Waste rock and tailings are the “leftovers”, or solid waste, from extracting the metal ores (Back Forty Mine). They also pollute the soil making it dangerous to grow crops in the area. The machines used to physically mine are powered by fossil fuels which emit harmful toxins like CO2, an airborne waste. This all has adverse effects on the inhabitants of the area of the mine (Lu). Most of the iron mining occurs increasingly in China while the US supply is decreasing (“Overview”). Since most magnet industries are centralized in the US, they are dependent upon importing vast amounts of iron from overseas so they can manufacture them over here. The second raw material is strontium carbonate, which is strontianite in its natural form. Strontianite forms at low temperatures and is usually found in veins of celestite. It was originally found in Scotland but it also comes from Germany and small amounts have been found in the US (Helz). It is unknown exactly where and how much the strontianite gets mined in present day. Little has been found about strontium mines in general. But the mining and extraction process would be similar to iron mining albeit a smaller scale. From mining, the raw materials are transported for manufacturing.
The manufacturing, processing, and formulation phase adds more waste to the life cycle equation though seemingly not as detrimental to the environment as mining. Ceramic magnets are essentially finely powdered iron oxide compound formed under heat and pressure. The first step is to heat the iron oxide and strontium carbonate up to 2000 degrees Fahrenheit and mix together to create ferrite (an iron compound). Then it is reduced into small particles where it can either be milled powder dried or injected into a die (in a wet slurry form) in a hydraulic press. The slurry is then compressed in a magnetic field. The water allows the ferrite particles to align themselves in the magnetic field but most of the water is removed during compaction and any remaining water is evaporated during the initial stages of sintering. (“What Are Ceramic Magnets”) Sintering is when two metals are combined without being melted. Sintering takes place at 2000 degrees Fahrenheit (Rahaman). Once sintering is done, the magnets are dense enough to grind to specific shapes for whatever product it will be used for though only diamond abrasives can be used since the magnets are hard and brittle. Ceramic magnets can also be made flexible if mixed with a binding material like rubber or plastic. Magnets usually get a coating of rubber or polytetrafluoroethylene (“How Are Ferrite Magnets Made.”). The process takes a lot of energy heating the materials which, if it is assumed that the electricity that is powering the machines is created by fossil fuels or coal, then there is much waste produced as well in terms of CO2 and other harmful greenhouse gases. Water and swarf (waste metal powders and filings from the grinding and filing process) are also wastes in the production of magnets (Ames Laboratory). The specific sintering machines give off exhaust gas that is made up of dust, Sulphur compounds and nitrogen oxides which is an extremely harmful airborne waste (Kashiyou). Once the magnets are completed, they get packaged up and shipped out which creates even more waste.
Distribution and transportation stack up even more waste to this life cycle. Dura Magnets package their ceramic magnets prior to shipping with plastic spacers between them, wrapped in corrosion inhibiting paper (VCI) and then formed into bricks and then wrapped in cardboard or foam. The plastic spacers are most likely thrown out after use, becoming a product of waste in the life cycle (it is unknown what exactly becomes of them). The VCI paper is formed using nitrites and amines which are harmful compounds known to cause cancer (Wolff). In addition, the paper only has a two-year shelf life if preserved correctly. After its use, it goes to the landfill. Now some companies actually use bio materials and make the paper so it is recyclable (“Green VCI”). This is a step in the right direction of reducing waste. Once they’re all packed, magnets are assumed to be transported by freight trucks which usually use diesel fuel which causes air pollution from the greenhouse gases. Only in extreme cases are magnets shipped via airplane which even then produces more air pollution since planes are fueled by gas (“Ceramic Magnet Handling & Storage”). Also, the iron from China would be shipped via cargo ships which uses waste oil (the leftovers from crude oil refining) giving off yet another air pollutant. These ships use anywhere from 50 to almost 400 tons of fuel per day, and it is the most polluting oil fuel (“Big Polluters”). It is assumed that strontium carbonate comes from overseas which would require even more freight ships. Both materials (iron and strontium carbonate) would have to travel by freight trucks once on land (which produces even more CO2) to get to the factories. Distribution, transportation, material acquisition, and production create the majority of the waste, there is little waste in maintenance, recycling or waste management.
Since magnets require no maintenance, there is no waste that is produced when magnets are used. Once a consumer is done with their magnet it goes to the landfill; no information was found in regards to recycling finished magnets. There is a positive aspect in the magnet production process: the waste management/recycling. There is a relatively new way of removing the nitrogen oxides from the exhaust gas of the sintering machines. Not only does it remove the harmful chemical, but it does not require a special apparatus or temperature raising fuel to do this. (Kashiyou) The residues and waste particles produced from grinding and filing the magnet can be put back into the process of making new magnets in the same factory. This actually not only saves more raw materials from being used but also energy because these reusable particles are already magnetized. (“Recycling of Strontium Ferrite Waste”) This process efficiently uses their waste and by-products to make more product. This is a bright side to the life cycle of magnets but it is hardly enough to make up for the bulk of the waste produced during the previous phases.
Ceramic magnets, from the acquisition of raw materials to recycling and waste management, are responsible for a lot of waste. The solid, waterborne, and airborne wastes of mining are perhaps the most harmful since it is at such a large scale. Most of the mining occurs in China where the communities are affected by the pollution. Then after mining, the iron and strontium carbonate are shipped overseas to the US where the magnet industries are. The cargo ships use a massive amount of dirty fuel that pollutes the water and the air. The production of ceramic magnets requires the metals to be heated at high temperatures to mix and sinter. They are pressed, magnetized and cut producing even more wastes. These include the fuels it took to run the equipment (electricity-fossil fuels), exhaust gas from sintering (Sulphur compounds, dust and nitrogen oxides), water and swarf. Once the magnet is completed, the wastes are not. The packaging includes plastics, foams and specially calibrated paper (VCI) all involving producing wastes and contributing to the landfill. The magnets then have to be transported from the factory to the consumer or seller which cause more of the harmful airborne wastes (CO2). Once the consumer is done with the magnet, it gets thrown in a landfill since it can’t be recycled. But the future of magnet production is not as dismal as it appears. The filings and leftovers from grinding the magnets are put back into the production process and reused saving energy and reducing waste. Also, the nitrogen oxide from the sintering machine can be removed, reducing the harmfulness of the airborne waste. Overall though, ceramic magnets, even though they are only composed of two raw materials, when all is said and done, the life cycle of a magnet produces significant solid and airborne, and waterborne wastes.
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