Principles of Distillation
What 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 waste solvents? Solvent-based waste contains volatile material (solvents) and non-volatile material (contaminants like paint, ink, grease, fiberglass, etc.). Many of the non-volatile contaminates are 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 boiling point. It then evaporates (vaporizes) and passes through the condenser where heat is removed from the vapor and it turns back into a cool, clean 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 drum 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!). Fractional...
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