Evaporation equipment

Evaporation. Evaporation can be used to separate volatile compounds from nonvolatile components and often is used to remove residual moisture or solvents from soHds or semisoHds. Thin-film evaporators and dryers are examples of evaporation equipment used for this type of appHcation. Some evaporators are also appropriate for aqueous solutions. 

There are numerous applications in solvent recovery processes where evaporation equipment are employed. Figure 14 provides an example of a process scheme for toluene-di-isocyanate recovery. This is an example of continuous vacuum evaporation of distillation residues. 

Parker, N. Agitated Thin-Film Evaporators-Equipment and Economics, Chemical Engineering, Sept. 13, 1965, p. 179. 

An engineer working on the selection of optimal evaporation equipment must list what is known, unknown, and to be determined. Such analysis should at least include the following ... 

Evaporation equipment, 10 154-155 Evaporation retardants, in finish removers, 18 78... 

A rotary evaporator equipped with a constant-temperature water bath is ideal for this purpose. 

Rotary evaporator equipped with water aspirator pH meter... 

Vital disadvantages in three layer resist (3LR) as MLR systems are a substantial increase in process steps and the need for the evaporation equipment that is used for forming the middle isolation layer. 3LR system consisting of a thin topmost imaging layer, a middle isolation layer and planarizing layer needs more than 11 steps to form a resist pattern (/). To minimize the processing steps, several materials for two layer resist (2LR) system have been proposed (4-8). A 2LR system can eliminate the middle isolation layer. It takes only 6 steps to accomplish the resist process and it is just a 2 step increase compared with 1LR system. 

Heating by condensing vapors, usually by saturated steam, is a very common practice in chemical and bioprocess plants. Liquid boiling and vapor condensation also occur in distillation or evaporation equipment. 

Extractive distillation processes are still widely used for nitric acid concentration. Because the operational and maintenance problems associated with sulfuric acid concentration plants are considerable, and their capital cost substantial, attention has been directed periodically to the use of extractive agents other than sulfuric acid. Phosphoric acid (I) acts like sulfuric acid but poses similar problems of reconcentration. Solutions of certain metallic salts, in particular metallic nitrates, permit similar enhancement of relative volatility and are readily reconcentrated in straightforward evaporation equipment, offering the possibility of a compact integrated concentration process. 

IMPORTANT NOTE Use high-purity nitrogen only, otherwise impurities of 02 will oxidize the lipids (see Critical Parameters). A multiport nitrogen evaporator equipped with a distribution manifold and water bath is highly recommended for this application (Fig. Dl.2.1). 

Remove chloroform from lipids using a rotary evaporator equipped with an aspirator. 

Place the filtered proanthocyanidin extract into an appropriately sized round-bottom flask and remove acetone on a rotary evaporator equipped with a water aspirator or vacuum pump, at 40°C. 

Figure 1. Thin-film evaporator equipped with a fixed blade rotor (Luwa)...

The difference in processing behavior between rotors provided with straight blades and those with pitched blades is shown in Figure 6 by an application referring to solvent recovery from a polymer solution of low initial viscosity. The evaporation capacity of a thin-film evaporator equipped with straight blades decreases considerably as soon as the concentrated polymer reaches a viscosity between 1000 and 2000 P. The greatly increased mean film thickness that characterizes this vis-... 

The by-product of sap concentration by an RO, permeate, is also used in maple operations as a source of very clean water. Due to the low mineral concentration of permeate water, it is used for cleaning tubing and evaporator equipment, as well as the RO membrane itself, which should be run through a wash and rinse cycle after each use. The chemicals and dosage to be used are specified by the membrane and RO manufacturers, and should be carefully followed to avoid damaging the membrane or contaminating the sap concentrate. 

FIGURE 4.7 Maple syrup produced in paired evaporators boiling sap from the same source on the same dates. The evaporator that produced the syrup on the top was the standard, control evaporator. The syrup on the bottom was produced in an identical evaporator equipped with air injection. 

In the early days comparatively simple vacuum evaporative equipment was... 

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