Evaporators Basket

The tube proportions in the basket evaporator are about the same as in the standard vertieal. One important feature of the basket-type evaporator is the ease with which a deflector may be added in order to reduce entrainment from spouting. The boiling in the vertical-tube evaporator is quite violent, and this tends to cause entrainment losses. This condition is accentuated if the liquor level in the evaporator is low. A baffle such as shown in Figure 9 largely prevents these losses and is much more easily added to the basket type than to the standard type. Other differences between the standard and the basket type are largely details of construction. 

Basket Type Evaporators - the first basket - type evaporator was built in 1877 and an example of this type is shown in Figure 10. In this evaporator the liquid is inside the tubes, the steam is outside the tubes, but the downstage instead of being eentral is annular. In this eonstruetion the entire heating element is a single unit whieh may be removed bodily for repairs. The evaporator has a eonieal bottom, but flat bottoms are also eommon in this type. 

Fertilisers For nitrates, non-molybdenum austenitic steels are satisfactory, but in the manufacture of ammonium sulphate some free acid is often present, so that evaporators and centrifugal dryer baskets in this case are generally made from molybdenum-bearing steels. For super-phosphates this has limited application. 

Resistive Heating Combined with Reaction Zone. The simplest way to form nitride UFPs on a laboratory scale is to adopt the reactive gas condensation method with a resistive heating evaporator. UFPs of the Fe-N system were synthesized by evaporating iron from a tungsten basket heated to 1600-2300°C in NH gas pressure of 27 kPa (37). Crystalline phases of a-Fe, y-Fe including about 2.5wt% of nitrogen, and y -Fe4N depend on the NH3 gas pressure and the evaporation temperature. 

Bound rubber - The bound rubber content was measured with toluene as solvent [48,49]. The nonvulcanized samples (0.2 g) were cut into small pieces and put into a steel-wire basket of very fine mesh, which was immersed in 100 mL of toluene at room temperature for 72 h. The solvent was renewed after 24 h. The extracts were collected and left for 24 h in air and 24 h in vacuo at 105°C to evaporate the solvent. The amount of bound rubber (BdR) is expressed as the percentage of the total polymer content in the compound. 

We refer to the simplified scheme depicted in Fig. 9.11-2, where the main vessels are the washing chamber C, the storage tank ST, the operative tank OT, and the evaporator or still ET. Of course, the chamber is provided with an agitation device and with a completely drilled basket, into which garments are placed. 

The mixture of two liquid phases is cooled in water cooler E-103 and then separated in brine decanter V-103. From that vessel the lighter phenol phase proceeds (P-108) to a basket type evaporator D-101 that is heated with steam. Overhead vapor from... 

The material to be evaporated is placed in a sample holder. Frequently, these sample holders are indented strips of W, Ta, or Mo, or wire baskets of the same metals, or carbon crucibles. These sample holders can be heated resistively by passing a large current through them, thus melting and then volatilizing the material. Alternatively, the sample holder can be bombarded by low-energy electrons to heat the sample. The entire process takes place in vacuum. Under reduced pressure, most... 

Silver evaporations were done in the same preparation chamber using an inhouse-constructed evaporation assembly containing a resistively heated tungsten basket. Ag coverages were controlled by a quartz crystal thickness monitor. The deposition rates were typically 0.01 to 0.1 A/s depending on the desired coverage. Coverages were subsequently calibrated by XPS analysis of the Ag 3d and polymer core level (C Is and O Is) intensities as compared to known standards, and by neutron activation analysis (111. 

Extraction and Isolation of Herbicide. (1) Place 100-gram portion of air-dried sample in basket of Immerex extractor. Add 250 ml. of acetone-hexane (1+9) to the metal container, and assemble extractor with basket in raised position. Using low heat setting on hot plate, extract the sample for 4 hours. Transfer extract to beaker, and evaporate just to dryness, using low heat and stream of dry air. 

Deposition of metals can be accomplished in one of several ways. The simplest is by thermal evaporation in a high-vacuum system (base pressure < 1 X 10 Torr) Au and Al, contained in or distributed over a tungsten basket or filament, melt and deposit by evaporation from the liquid phase. Cr sublimes from the solid when heated, typically in a W basket. Ti cannot be deposited thermally, which may be why it does not replace Cr altogether. 

The continuous centrifuge is fed with salt slurry from the evaporators. Figure 5 shows the main components and operating principles for this type of unit. The salt slurry from the evaporators is continuously fed from the top inlet where it falls between the helicoidal blades of the extractor and the conical basket. The basket... 

Larger oligonucleotide solutions can be desalted on DEAE-cellu-lose and the desalted solution concentrated by rotary evaporation, freeze drying, dialysis against Ficoll or gel filtration in a basket centrifuge depending on what apparatus is available. These methods are described below. 

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