Separation equipment, design

D. R. Bennett and co-workers, Cyogenic Air Separation Equipment Design, AIChE Tutorial on Cryogenic Technology, Houston, Tex., 1993. 

Shortcut Equipment Design Methods tend to become buried in design procedures, even computer-based ones. Therefore they often become part of the mix and don t stand free as separate entities. This is not bad. These methods need to be placed wherever they are useful. However, it is also good to draw them out since many everyday problems can be solved with undiluted shortcuts. 

Particle size distribution (R) Design of separation equipment Toxic hazard Environmental impact Wide range including Microscopy Holography Light scatter Sieving... 

Overall boiler design, including steam and water space dimensions, boiler rating, pressure, and separation equipment arrangements. 

Ibsen, K., Equipment design and cost estimation for small modular biomass systems, synthesis gas cleanup, and oxygen separation equipment, Contract Report NREL/SR-510-39943, NREL Technical Monitor, Section 2, May 2006. 

Column size is another important consideration. For equipment designed for most routine laboratory HPLC situations the relative sensitivity of APTelectrospray instruments is better at low flow rates (0.2-0.8 mL/min) whereas the relative sensitivity of APCI instruments is enhanced at high flow rates (0.5-2 mL/min). As a result, small columns are appropriate for API-electrospray/MS and, if only one or two compounds of interest are found in a particular sample, high-resolution separations are not necessary. For APTelectrospray analysis of complex samples, 150 mm x 4.1 mml.D., 3 pm columns (flow 0.5-1.0 mL/min) are usually sufficient. For drug quantification involving analysis of single or low numbers of compounds, small columns such as 30 mm x 2.1 mm I.D., 3.5 pm columns (flow rate 0.2-0.4 mL/min) provide sufficient separation and a saving in both column cost and solvent utilization. The reduced injection volume required for the small columns often results in better resolution and increased sensitivity. 

Many industrial processes begin with a leaching step, yielding a slurry that must be clarified before solvent extraction. The solid-liquid separation is a costly step. The solvent extraction of unclarified liquids ( solvent-in-pulp ) has been proposed to eliminate solid-liquid separation. The increased revenue and reduced energy cost make this an attractive process, but many problems remain to be solved loss of metals and extractants to the solid phase, optimization of equipment design, effluent disposal, etc. 

You have learned or will learn about the separation components of a chemical process in mass transfer and separations courses. The energy requirements of separation processes, the purities of different streams from separation equipment, and possible integration of heat flows between units are frequency important in design. 

The future of azeotropic distillation may well be in the development of new and more efficient azeotrope formers for the specific separations desired. Design methods and equipment for azeotropic processes are essentially the same as for ordinary fractionation hence, substantially all developments in that field will be applicable to azeotropic distillation. 

The papers in this section represent the theory and current industry practices in the separation process and in separator design. Because separation is such a basic requirement for the oil and gas industry, a wealth of information has been published concerning the process and the various design techniques used in the manufacture of separation equipment. Some of these techniques are proprietary, however, and the details of the design are not readily available. For instance. British Petroleum has done considerable design and testing of cyclone-type separation equipment in recent years with the objective of miniaturizing the equipment for use on offshore platforms. For further details on this and other proprietary equipment, one must contact the manufacturer or licensee of the equipment. 

In Oil and Gas Separation Is a Science." Worley and Laurence review the basics of oil/gas separator designs and discuss their mechanism and mechanics. Different types of separators are described, along with the governing laws and equations associated with the design of separation equipment. 

It is usually very important to design separation equipment for the maximum flow rate of both gas and liquid rather than a 24-hour average rate. Only when the maximum possible rate is of a short duration, infrequent, and the application will allow occasional liquid carryover, can equipment be designed for less than the maximum instantaneous flow rate. 

Because of continuing problems with wash tanks as water separation equipment, a commitment was made to design a high-rate separator based on the API model separator. The primary design criterion was its effectiveness at rates of more than 25.000 B/D (3975 m3/d). Secondary criteria were ease of construction, durability, and low capital costs. 

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