Chemical engineering operations

In the petroleum refining and natural gas treatment industries, mixtures of hydrocarbons are more often separated into their components or into narrower mixtures by chemical engineering operations that make use of phase equilibria between liquid and gas phases such as those mentioned below ... 

These operations, which are routine chemical engineering operations, have been treated extensively in other sections of this handbook. 

The separation of mixtures of immiscible liquids constitutes one of the important chemical engineering operations. This empirical design has proven satisfactory for many phase separations. 

Table 7.21 Safety features in chemical engineering operations...

Processes for the control of atmospheric emissions are summarized in Table 17.9. Some of these involve the types of chemical engineering operations referred to in Chapter 7 the added complications are ... 

Any of the variety of chemical engineering operations or unit processes listed in Table 17.10 may be used to treat aqueous effluents. Oxidation includes both chemical and biological processes the latter include trickling filters or an activated sludge bed. 

Today, specialized microstructured equipment is available for many chemical engineering operations such as gas, liquid, gas-liquid, and liquid-liquid processing, largely without involving solids (Hessel et al. 2004a, 2005d Ehrfeld et al. 2000 Jensen 1999, 2001 Fletcher et al. 2002 Haswell and Watts 2003 Gavriilidis et al. 2002 Jahnisch et al. 2004 Kolb and Hessel 2004 Pennemann et al. 2004). This is further... 

Larian, M.G., Fundamentals of Chemical Engineering Operations. Englewood Cliffs, N. J. Prentice-Hall Inc., p. 542 (1958). 

The greatest safety hazard in chemical engineering operations is without question caused by uncontrolled chemical reactions, either within the chemical reactor or when flammable chemicals escape from storage vessels or pipes. Many undergraduate students are never exposed to the extremely nonlinear and potentially hazardous characteristics of exothermic free radical processes. 

Modification of the metal itself, by alloying for corrosion resistance, or substitution of a more corrosion-resistant metal, is often worth the increased capital cost. Titanium has excellent corrosion resistance, even when not alloyed, because of its tough natural oxide film, but it is presently rather expensive for routine use (e.g., in chemical process equipment), unless the increased capital cost is a secondary consideration. Iron is almost twice as dense as titanium, which may influence the choice of metal on structural grounds, but it can be alloyed with 11% or more chromium for corrosion resistance (stainless steels, Section 16.8) or, for resistance to acid attack, with an element such as silicon or molybdenum that will give a film of an acidic oxide (SiC>2 and M0O3, the anhydrides of silicic and molybdic acids) on the metal surface. Silicon, however, tends to make steel brittle. Nevertheless, the proprietary alloys Duriron (14.5% Si, 0.95% C) and Durichlor (14.5% Si, 3% Mo) are very serviceable for chemical engineering operations involving acids. Molybdenum also confers special acid and chloride resistant properties on type 316 stainless steel. Metals that rely on oxide films for corrosion resistance should, of course, be used only in Eh conditions under which passivity can be maintained. 

Edit, " Fundamentals of Chemical Engineering Operations , Prentice-Hall, Englewood Cliffs, New Jersey (1958), pp343-424 (Distillation) 20) Encyclopedia of Explosives, PATR 2700, Vol 1 (I960), p A518(Azeotropy) 21) Perry, 4th Edit (1963), pp 13-2 to 13-55 22) Kirk... 

Control in one form or another is an essential part of any chemical engineering operation. In all processes, there arises the necessity of keeping flows, pressures, temperatures, compositions, etc. within certain limits for reasons of safety or specification. It is self-evident that automatic control is highly desirable, as manual operation would necessitate continuous monitoring of the controlled variable by a human operator and the efficiency of observation of the operator would inevitably fall off with time. Furthermore, fluctuations in the controlled variable may be too rapid and frequent for manual adjustment to suffice. 

The various steps in recovery of biological products from their natural environment have been divided into four categories.1 These are separation of solubles from insolubles, isolation, purification, and polishing. Separation of solubles from insolubles is a common chemical engineering operation and... 

M.G.Larian, "Fundamentals of Chemical Engineering Operations, Prentice-Hall, Englewood Cliffs, NJ(1958), 415-21... 

The applications of the stochastic theory in chemical engineering have been very large and significant [4.5-4.7, 4.49-4.59, 4.69-4.78]. Generally speaking, we can assert that each chemical engineering operation can be characterized vdth stochastic models. If we observe the property transport equation, we can notice that the convection and diffusion terms practically correspond with the movement and diffusion terms of the Fokker-Plank-Kolmogorov equation (see for instance Section 4.5) [4.79]. 

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