The thermal conductivity of hydrocarbons is an essential parameter that needs to be known when designing heat transfer equipment. Presented here is a simple-to-use correlation that was developed for predicting thermal conductivities of liquid paraffin hydrocarbons, petroleum fractions and atmospheric…
Laminar Pipe Flow For steady flow in a pipe (whether laminar or turbulent), a momentum balance on the fluid gives the shear stress at any distance from the pipe centerline. In Equation (1), Φ = P + ρ gz. The…
In a fired thermal fluid heater, a thermal fluid is heated by the metal surfaces of a fired heater or fluegas heat-recovery exchanger. Generally, the heat input rate is controlled to achieve some desired bulk-fluid temperature exiting the heater. However,…
Organic-based thermal fluids provide relatively trouble-free service for significant periods of time. However, there comes a time when any fluid (either aromatic- or aliphatic-based) needs to be replaced. Since aromatic-based fluids generally cost more and are complicated to dispose of,…
Lubricant contamination in gearbox bearing housings can substantially reduce gear life. In critical applications, dual-face, magnetic bearing-protector seals will keep contamination out (Figure 1). Dual-face, magnetic bearing protectors are preferred in many difficult applications, such as wet cooling tower gearboxes,…
Engineers often need to fit experimental data to an empirical relationship for extrapolation or modeling without resorting to a full mathematical treatment based on physical principles or theory. The most widely used platform in science for doing this is MS…
Process modeling has progressed from the "molecule accounting" of steady-state flowsheeting packages to become a central platform for capturing and deploying chemical process industries’ (CPI) intellectual property (IP). Systematic modeling has moved center stage to help companies differentiate themselves from…
Pressure relief systems are vital in the chemical process industries (CPI) for handling a wide variety of situations. They are used to prevent pressurization above a system’s design pressure; for venting during an unusual or emergency situation; and for…
Biodiesel can be produced from vegetable oils by three types of reactions: base catalyzed transesterification of the oil; direct acid-catalyzed transesterification of the oil; and conversion of the oil to its fatty acids, and then to biodiesel. Biodiesel is typically…
Management is a process of managing risk; maintenance management is a process of managing risk for operational reliability. Since it is hard to manage what cannot be measured, effective maintenance management demands good data on machine health — a comprehensive…