Material Waste Materialwaste has 10 subdivisions:Paper: Paper is decomposedinto fibers(pulp); they are filtered and chemically treated to elimnateimpurities and then used to create new paper that subsequentlyserves for different uses. Glass: Firstly, any other materials like plastic,paper, organic left-over(food) are separated and then the glass is crushed andmelted. After this process, glass is pure and it can be chemically treated tohave various colors and compositions.Textiles(any fabric fiber products, like clothes, household goods, oreven unused material scraps from clothing industry) Natural and synthetic textile meterials are sorted and thenchemically cleaned(to eliminate impurities).
Depending on their type(cotton orpolyester, for example), they are processed and new textile fibers are made.These new fibers are sent to the industry units as raw materal.Plastics: This material can be recycled to produce new plastic goods orliquid fuel Plasticis transformed into liquid fuel by “cross-alkane metathesis”, which is aprocess to break the polymers’ bounds that form plastic mass. This method hasbeen developed by University of California, Irvine and Shanghai Institute ofOrganic Chemistry’s scientists. Further credit is given in the “Sources”section Plasticcan also be melted(depending on the plastic type) to obtain new shapes andproducts, through a process called Plasma Pyrolysis.Putrescibles(including food, dead plants or animals, manure) Two very important products can be obtainedby recycling putrescibles: biogas and biofertilizers. · Anaerobic Digesters: theytransform waste into biogas fuel(mainly methane), which can be used to generateelectrical power for the industry systems.· Digester which use enzymes: theenzymes decompose the waste, so that the organic matter can be used to producenutrient-rich substances(these substances are very useful in Agriculture=biofertilizers)Chemical Waste(including fuel and oils): substances must beseparatellyprocessed.
If not separated, dangerous chemical reactions could happen; forexample, combinations of oxidizers and acids/metals may lead to toxiccompounds.Used oils contain many impurities and they can be veryharmful to the environment in case they aren’t recycled properly(even if thereon Sileo Ibis doesn’t exist a large amount of oil). By re-refining the oil,ethlyene glycol can be obtained(this can be used as anti-freeze, heat-transferagent or even in polymers’ production). After dehydrogenation of waste oil,lighter oil(which boils faster) is separated and it contains water and ethlyeneglycol. The rest of the oil(that is havier and doesn’t even reach boiling) goesthrough Purification Systems and Hydrotreating Reactors in order for thecarbon-chains to become saturated with hydrogen. At the end of the process, theoil is safe to use. Metals: firsly, ferrous metals are separated from non-ferrous and thenthe metals are shredded, in order to minimize the amount of power(heat) usedfor melting; Then electrolysis is used to purificate the material.
Metal reachthe solid state after cooling and it is sent to industry as raw material.Electronics: at the beginning of the recyclesystem, other objects(batteries, toners, memory cards) which were attached tothe electronics are separated and sent to appropriate recycling/storing units.Then the metals are shredded and separated by the Magnetic Separator.Afterwards the metal is melted at high temperature(the meltingtemperatures differs depending on themetal), compressed and then sent to industry’s units. Wood: firstly, metals,plastics, papers(such as nails, design objects or labels) are separated fromwood and they are sent to the appropriate recycling units. Paints and varnishedare also removed.
The wood(either pallets, sawdust or any other form) is thenshredded and eventually compressed(depending on purpose) to be used as asecondary raw material.Buildingmaterials(mainly regarding ceramics): The piecesof material are crushed and then instruments with magnets can be used to removeother components(metals). The crushed material goes through a machine thatworks like a mill: it grinds the materials till they become powder.
This rawmaterial is then sent to the industry’s units to be used as building material. All the wasteis collected separately(as established in the subdivisions) and transportedfrom every module through pipes to the Material Waste Processing Units. Theseunits filters the waste and process it in order to obtain raw materials forindustry. This way, the waste is wholy recycled to obtain new products.
Regarding the spacecraft’s conditions and howall the systems function, we calculated the percentages of every subdivision’swaste amount per day(the percentages are estimated and they may slightly differfrom day to day, as the amount of waste can’t be exactly the same daily) Waste heat The reason why wasteheat must be recovered is because it has a great potential of producingelectrical power. There are machines that produce large amounts of wasteheat(for example, the machines used in industry) and others which producesmaller amounts of waste heat(for instance, various electronics: laptop,refrigerators, TVs etc). Large amounts of waste heat.Two significant components of therecovery system is the Heat Exchanger(where two fluids can transfer heat fromone to another; without direct contact being necessary) and the Power Generator(wherefluids raise in temperature by using the waste heat; after the process,electricity is conducted to the consumer) Smaller amounts of waste heat. One way of saving this heat is by addinga thermoelectric layer to the energy consumer: the waste heat is conducted to aspecific place where it is turned into electrical power. This way, themachine/device uses electric power from it’s own waste heat.