Principles of Distillation Essay Example for Free

Principles of Distillation EssayWhat is distillation? Simply, distillation is the process in which a liquid is vaporized (turned to steam), recondensed (turned back into a liquid) and collected in a container. Nature uses a form of distillation to turn salt water (seawater) into fresh water (rain). Why do you use distillation to recycle negate solvents? Solvent-based waste contains inconstant material (solvents) and non-volatile material (contaminants like paint, ink, grease, fiberglass, etc.). Many of the non-volatile contaminates atomic number 18 dissolved in the solvent (like salt dissolved in salt water) and cannot be filtered-out. Distillation is an ideal way to separate the two. Why is distillation an ideal way to separate the two? During the distillation process, the solvent-based waste is heated until it reaches the labouring point. It thus evaporates (vaporizes) and passes through the condenser where heat is admitd from the vapor and it turns back into a cool, cl ean reusable liquid (same process that causes dew to form). Fortunately, contaminates are typically not volatile (easily vaporized) and stay behind in the distillation tank. You say contaminates are typically not volatile, does this mean some are?Occasionally there are cases where a potential customer wishes to separate a volatile solvent from another volatile material. This is not the typical customer. Some cases include customers using an alcohol to remove water from parts to dry them or where they have solvent mixtures due to poor house keeping practices (they lump all waste solvents into one tucker out from different operations like painting and parts cleaning). To separate one volatile from another effectively requires fractional distillation our process uses simple distillation. What are the differences between simple distillation and fractional distillation? Simply stated, in simple distillation, what you put in is what you get back, but it is free of non-volatile materials (it is clean). half(prenominal) distillation is much more complicated (and expensive). It is the base process where crude oil is turned into the many items that come from oil. Fractional distillation is not needed for virtually all solvent recycling applications.What is clean distillation? Vacuum distillation is the distillation of a liquid on a lower floor reduced compact. The atmospheric pressure in the distillation tank is reduced making it possible to boil the liquid at a lower temperature. Liquids boil at lower temperatures under reduced pressure (the inverse is that a liquid boils at a higher temperature under pressure, which is why they use a pressure cap on an automobile radiator to increase the boil point of the engine coolant to prevent boil- everyplace). Why do you use vacancy distillation? Vacuum distillation is used to safely recover higher boiling point solvents. We limit the maximum temperature of the distillation units heater. There is a temperature at which a flammable or combustible material can ignite by temperature only, this is called the autoignition temperature (this is discussed later). Some solvents boil at temperatures that exceed the temperature that the distillation heater can reach (392 Fahrenheit). Vacuum distillation lowers the boiling point to allow recovery within the heaters maximum setting. When do you use vacuum distillation?It is used to safely recover solvents with boiling points over 300 Fahrenheit. Vacuum distillation should not be used on solvents with boiling points below 200 Fahrenheit. If the maximum heater setting is 392 Fahrenheit, why do I need to use vacuum distillation for solvents with boiling points over 300 Fahrenheit, dont you mean solvents with boiling points over 392 Fahrenheit? No When boiling a liquid, two factors come in to play. One is the requirement to have a driving force force to force the liquid to boil and vaporize. This driving force is in the form of extra temperature to allow the solve nt to develop a good rolling boil. The other factor is the role of the non-volatile residue. As you boil off solvent and the remaining mixture in the distillation tank becomes more concentrated in the nonvolatile material, the vapor pressure drops (Raoults Law) and intimately important, the boiling point goes up So bottom line is that you need 50 to 100 degrees of extra temperature to do a good job of boiling the waste solvent.Also, the concentrated non-volatile material acts as an insulator towards the end of the process as it becomes more and more concentrated. So, as the percentage of non-volatiles in the contaminated solvent increases, the required heat to completely distill the mixture also increases. Sometimes solvents that have boiling points of 318F (Xylene) may not require a vacuum if they are not highly contaminated but almost definitely would if the solid content was greater than, lets say 10%.Pulling a vacuum on such a mixture will reduce its boiling point and the overa ll time to process it. How is the vacuum created? The vacuum is generated using our JetVac technology. A stainless steel reservoir is primed once with clean solvent. A small stainless steel pump is immersed in the liquid and is attached to an explosionproof electric car motor. When the motor is started, clean solvent is drawn into the pump and forced through a metal tube known as an aspirator. The aspirator looks like an open valet de chambre of pipe with a small orifice (hole) on one side. As the high velocity fluid is pumped across the face of the orifice, it creates suction (like a venturi on a carburetor). Air is pulled through the venturi from the distillation system and passes through a vent.