The concentrations of Ag, Cr, Cu, Fe, Ni, Pb, and Sn in used jet-engine and reciprocating-engine oils have been determined by atomic absorption, using atomization from a cavity in a heated graphite rod. The samples analyzed were taken from those provided by the United States Air Force Spectrochemical Oil Analysis Program (S.O.A.P.) during the period May 1969-December 1971. This enabled a comparison to be made between the present results and those obtained by flame atomic absorption by the laboratories participating in S.O.A.P. Excellent agreement between the two sets of results was found for Ag, Cu, Fe, Ni, and Pb. The use of the graphite-rod atomizer led to results for Cr that are considerably higher than those found with an air-acetylene flame, but are comparable with results obtained with a nitrous oxide-acetylene flame. It appears that most of the Sn concentrations are near, or below, the levels detectable with flame atomization, and in some cases Sn was also undetectable with the graphite-rod atomizer.Application of trace element analysis to the determination of wear-metal particles suspended in the lubricating oils of railroad and aircraft engines has been firmly established for many years. Early methods of analysis included colorimetry (after ashing and dissolution of the sample) (7), and a number of direct emission spectrographic techniques, discussed by Fry (2). Direct-reading emission spectrographs continue to be widely used. The past decade has seen the development of flame atomic absorption spectrometry (3-10) and preliminary investigations of flame atomic fluorescence spectrometry (77, 12). The range of applications of engineoil analysis for wear metals has been reviewed by Middledorf (13).Attention has recently been given to the possible advantages of using flameless atomization systems for oil analysis

A simple, versatile atomizer of the electrically heated graphite rod type is described and used for atomic absorption studies. The atomizer utilizes a burner head (directly under the rod) to produce a H2-Ar-entrained air flame; the flame is primarily useful in minimizing ambient air entrainment in order to maintain a highly reducing environment directly above the rod where atomic absorption measurements are generally taken. Temperature profiles of the H2-Ar-entrained air flames and also the temperatures of the graphite rod at various currents were measured, and appropriate plots are given. Several types of graphite and several different ways of holding liquid samples on the atomizer were also compared. Detection limits and analytical curves of aqueous solutions of Ag, As, Au, Cr, Cu, Fe, Mg, Ni, and Pb and oil-based solutions of Ag, Cu, and Fe are given. This atomizer should be of even greater use for atomic fluorescence studies.

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Offshore production facilities utilize a variety of process heating equipment to help start-up production and operate efficiently. Applications include glycol reboiling, oil and gas conditioning, knock-out drum heating, molecular sieve regeneration, sea or potable water, and fuel/lube oil maintenance. In addition, oil producers have long investigated downhole and subsea heating solutions capable of decreasing viscosity, preventing wax and hydrate buildup, and providing localized heating for improved productivity. The types of heating solutions are problematic due to the large capacity and extreme environmental and process conditions involved, especially with the downhole and subsea applications. Until recently, low voltage (below 1000V) heating elements and low power heating cables have been the typical solutions for downhole and subsea electric heating applications. These traditional solutions have limitations that prevent them from significant adoption and utilization. This paper discusses the benefits of using medium voltage technology for flow assurance and hydrate prevention applications. The focus will be on the reduction of installation, maintenance, and operational costs, as well as the reduction of electrical power consumption and line loss associated with using medium voltage technology for such applications. For large heating loads, the physical size and footprint of medium voltage electric heating systems are more compact than traditional low voltage systems. This is especially relevant on newly designed platforms offering medium voltage power distribution. Finally, medium voltage electric heating technology opens the door for completely new solutions in downhole, subsea and offshore heating, as well as other process heating, in the oil and gas industry that were not possible before. It is important to present such innovation to the marketplace so that producers and operators are aware of new solutions to existing problems.

Offshore production facilities utilize a variety of process heating equipment to help start-up production and operate efficiently. Applications include glycol reboiling, oil and gas conditioning, knock-out drum heating, molecular sieve regeneration, sea or potable water, and fuel/lube oil maintenance. In addition, oil producers have long investigated downhole and subsea heating solutions capable of decreasing viscosity, preventing wax and hydrate buildup, and providing localized heating for improved productivity. The types of heating solutions are problematic due to the large capacity and extreme environmental and process conditions involved, especially with the downhole and subsea applications. Until recently, low voltage (below 1000V) heating elements and low power heating cables have been the typical solutions for downhole and subsea electric heating applications. These traditional solutions have limitations that prevent them from significant adoption and utilization. This paper discusses the benefits of using medium voltage technology. The focus will be on the reduction of installation, maintenance, and operational costs, as well as the reduction of electrical power consumption and line loss associated with using medium voltage technology. Also, for large heating loads, the physical size and footprint of medium voltage electric heating systems are more compact than traditional low voltage systems. This is especially relevant on newly designed platforms which provide medium voltage power distribution.Finally, medium voltage electric heating technology opens the door for completely new solutions in downhole, subsea and offshore heating, as well as other process heating, in the oil and gas industry that were not possible before. It is important to present such innovation to the marketplace so that producers and operators are aware of new solutions to existing problems.