Distributor high performance

C. Liquid Distributor (see Figures 4-9). According to Strigle, This is the most important column internal from a process standpoint. A liquid distributor is required at all locations in the tower where an external liquid stream is introduced. High-performance distributors provide a flow rate variation per irrigation point that is a maximum of 5% of the average flow. The geometric uniformity of... 

Hardware cost for high performance trays including distributors = D2 (52N, + 160)... 

Nutter offers an improved high performance random packing identified as Nutter Ring, see Figure 9-6K. To achieve the best performance from any random packing, the liquid distributor must be level and the distributor points of the discharging liquid to the packing must be uniformly distributed, see earlier discussion on this topic. 

A Norton [139] correlation for modern, random dumped packings used for distillation up to 200 psia is (use high performance internal distributors and supports) from surface tension of 4 dynes/cm but less than 33, and liquid viscosity of at least 0.83 to 0.08 cps but not greater ... 

For the sake of developing commercial reactors with high performance for direct synthesis of DME process, a novel circulating slurry bed reactor was developed. The reactor consists of a riser, down-comer, gas-liquid separator, gas distributor and specially designed internals for mass transfer and heat removal intensification [3], Due to density difference between the riser and down-comer, the slurry phase is eirculated in the reactor. A fairly good flow structure can be obtained and the heat and mass transfer can be intensified even at a relatively low superficial gas velocity. 

To quantify the quality of liquid irrigation, the correlation uses the distribution quality rating index. Typical indexes are 10 to 70 percent for most standard commercial distributors, 75 to 90 percent for intermediate-quality distributors, and over 90 percent for high-performance distributors. Moore and Rukovena present a method for calculating a distribution-quality rating index from distributor geometry. Their method is described in detail in their paper as well as in Kister s book (.Distillation Operation, McGraw-Hill, New York, 1990). 

Even now, the above considerations are the basis for FCB design. Elaborate devices are installed on the gas distributor and internals for high-performance reactions (Section I). 

Hardware cost for structured packings including distributors (for packings in the range of 100-250 m /m of surface and using high performance distributors)... 

The boundary layer theory has been widely accepted and used to describe the transport phenomena in CVD processes. High-performance CVD systems require designers to focus on the geometrical parameters of the reaction chamber, the orientation and arrangement of the preforms in the chamber, as well as some other important components, such as pipes, distributor, exit and so forth. Due to drag effects around the boundary layer of preforms, it is very important to design the preforms and the reaction chamber and aim to avoid the boundary layer separation such that they experience a minimum drag force. The details of these effects are discussed in Chapter 6. 

Sethi, ED. HPTLC, High Performance Thin-Layer Chromatography, Quantitative Analysis of Pharmaceutical Formulations, CBS Publisher Distributors, New Dehli (India) 1996, ISBN... 

Perforated-pipe distributors are normally of the ladder type (Fig. 3.4a) or the perforated-ring type (Fig. 3.46). Perforations are located on the underside of the pipes. The ladder type is usually easier to fabricate and therefore less expensive thsui the perforated-ring type. A high performance variation of the Fig. 3.4a distributor is shown in Fig. 3.56. 

Excessive liquid pressure drop through the distributor should be avoided, because this may restrict the number of drip points. The liquid line to the distributor should contain a control valve or a restriction orifice to let down any excessive pressure. A more satisfactory alternative is to use the high-performance perforated-pipe distributor variation which lets out liquid by gravity instead of pressure. 

Orifice distributors are usually of the pan type (Fig. 3.4d) or of the tunnel type (Fig. 3.4e). The former t3rpe is best suited for small-diameter columns (<4 ft), while the latter is used in larger-diameter columns (>4 ft). High-performance variations of the Fig. 3.4e distributor are shown in Fig. 3.5a, c and 3.6a, d. 

To improve jet instability, some high-performance distributors have each perforation equipped with a short, flow-straightening tube. This alleviates spray formation and minimizes any lateral... 

One source (289) recommends positioning high-performance distributors 4 to 6 in above the bed another designer (166) prefers 6... 

Glitsch, Inc., "High Performance Distributors, The Glitsch Column, No. 262A. 

Installed-cost data for high-performance liquid distributors and redistributors are also not widely available. Distributors should be placed at every feed point and, conservatively, redistributors should be used every 20 ft. In the absence of a vendor quote and for a very approximate estimate, the installed cost of a liquid distributor can be taken as 100/ft of column cross-sectional area. 

Distributor rotor arm in PEEK for high performance car, by Magneti Marelli (courtesy ICI). 

---