Heat and Mass Transfer in Chemical Engineering

In virtually every process of chemical technology (and also in many processes of everyday life) the transport of mass and heat is involved. The fundamental equations of (steady) heat and mass transfer and values of the thermal conductivity and of the diffusion coefficient of gases, liquids, and solids have been treated in Section 3.1.4. Building on that, this sub hapter dedicates itself to the following heat and mass transfer processes, which are particularly relevant for chemical engineering  

Wound heat exchanger. Courtesy of Linde Engineering, Germany. 

---

The presence of the film between the dispersed plug and the channel wall offers multiple advantages such as prevention from cross contamination between the segments in biological devices, and enhancement of the heat and mass transfer in chemical engineering processes. Film thickness can be affected by different parameters such as fluid properties, average velocity, flow rate ratio, and channel size. 

Heat, and Mass Transfer in Chemical Process, and Engineering Systems," ed. by Durst, F. Tsiklauri, C. V. Afgan, N. H. Hemisphere Publ. Corp. Washington, DC 1979, 835. 

Kurten, H. Hegner, B. In "Two-Phase Momentum, Heat, and Mass Transfer in Chemical Process and Engineering Systems". Ed. by F. Durst,... 

Jones OC Jr, Zuber N. Slug-annular transition with particular reference to narrow rectangular ducts, in Two-Phase Momentum, Heat and Mass Transfer in Chemical, Process and Energy Engineering Systems, (Eds.) Durst F, Tsiklauri GV, Afgan NH. Washington,... 

A more recent review by Fahidy (FI) concerns the chemical engineering approach to electrochemical processes, such as fluidized-bed reactors, bipolar particulate reactors, pulsed electrochemical reactors, gas-phase electrochemical reactors, electrocrystallization and electrodissolution, and the enhancement of heat and mass transfer in electric fields. In this review, the author also discusses dimensionless mass-transfer equations applied in cell design. Such equations are reviewed in greater detail in Section VI. 

S. Heinrich, L. Mori, G. Kruger, Modelling and experimental verification of the heat and mass transfer in fluidized bed spray-granulation, Proceedings, 2nd European Congress of Chemical Engineering ECCE-2, Montpellier, October 5-7,1999, No. 67, vol. 

Martin, H. Heat and mass transfer in fluidized beds. International Chemical Engineering, 22, No. 1 (1982). 

Edwards, W.C. and Adams, T.N., Simultaneous heat and mass transfer in wet wood particles. Second Pacific Chemical Engineering Conference on Heat and Mass Transfer in the Forest Products Industries, August 28-31, Denver, CO, 1978. 

Nelson, P. A., Galloway, T. R., Particle to fluid heat and mass transfer in dense systems of fine particles. Chemical Engineering Science, 1975, 30(1), 1... 

V. Gnielinski, New equations for heat and mass-transfer in turbulent pipe and channel flow. International Chemical Engineering, 1976, 36, 359-368. 

Hlavicek V, Hofmann H. Modeling of chemical reactors—XVII Steady state axial heat and mass transfer in tubular reactors. Numerical investigation of multiplicity. Chemical Engineering Science 1970 25 187-199. 

Strom H, Sasic S. Heat and mass transfer in automotive catalysts— the influence of turbulent velocity fluctuations. Chemical Engineering Science 2012 83 128-137. 

Votruba J, Mikus 0, Nguen K, Hlavacek V, Skrivanek J. Heat and mass transfer in monolithic honeycomb catalysts-II. Chemical Engineering Science 1975 30 201-206. 

ANSYS simulation enables engineers to study multiphase distribution, heat and mass transfer calculations, chemical kinetics and reaction of gas-liquid reactions. These include the design of plate columns, packed columns and bubble columns, a loop reactor and bioreactor development, gas-in-liquid dispersion studies and emulsion design. 

Sanga, E. Mujumdar, A. S. Raghavan, G. S. Heat and Mass Transfer in Non-homo-geneous Materials under Microwave Field, Presented at The 50th Canadian Chemical Engineering Conference, Montreal, Canada, October 15-18,2000. 

Simultaneous heat and mass transfer also occurs in drying processes, chemical reaction steps, evaporation, crystallisation, and distillation. In all of these operations transfer rates are usually fixed empirically. The process can be evaluated using either the heat- or mass-transfer equations. However, if the process mechanism is to be fully understood, both the heat and mass transfer must be described. Where that has been done, improvements in the engineering of the process usually result (see Process energy conservation). 

Stewart, W. S., Heat and Mass Transfer Coefficients for the System Air-Water in a Perforated Plate Column, thesis presented in partial fulfillment of Master s Degree in chemical engineering, Louisiana State University (1958). 

Heat and mass transfer limitations are rarely important in the laboratory but may emerge upon scaleup. Batch reactors with internal variations in temperature or composition are difficult to analyze and remain a challenge to the chemical reaction engineer. Tests for such problems are considered in Section 1.5. For now, assume an ideal batch reactor with the following characteristics ... 

---