Refinery Products and Test Methods

A complete discussion of the large number of routine tests that are practiced today could easily fill an entire book, and hence only the barest mention of test methods will be possible. Details of laboratory manipulation must be obtained from other sources, particularly Petroleum Products and Lubricants, an annual publication of Committee D-2 of the American Society for Testing Materials. 

A voluminous but much less satisfactory literature is available concerning the relation of routine test results and the performance characteristics of petroleum products. This is unfortunate, because to a large extent refinery operations should be governed or regulated by the performance of the products. 

Temperatures at which samples may be opened or poured without materially altering the composition of the sample are indicated in Table 3-1. Safe pouring temperatures from the standpoint of fire are even 

TABiiE 3-1. Approximate Relationship between Pouring Temperature AND Such Properties as Vapor Pressure, Flash Point, 

Reid v.p., psia Mash point, F Approx. 0-10% boiling range, F Ulustrative materials Pouring temp., F  

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Thus process units in a refinery require analytical test methods that can adequately evaluate feedstocks and monitor product quality. In addition, the high sulfur content of petroleum and regulations limiting the maximum sulfur content of fuels makes sulfur removal a priority in refinery processing. Here again, analytical methodology is key to the successful determination of the sulfur compound types present and their subsequent removal. 

Therefore, in this chapter we describe major refinery operations and the products therefrom and focus on their composition, properties, and uses. This presents to the reader the essence of petroleum processes, the types of feedstocks employed, and the product produced, as well as warning of the types of the chemicals that can be released to the environment when an accident occurs. Being forewarned offers an environmental analyst the ability to design the necessary test methods to examine the chemical(s) released. It offers environmental scientists and engineers the ability to start forming opinions and predictions about the nature of the chemical(s) released, the potential effects of the chemical(s) on the environment, and the possible methods of cleanup. 

Thus, fractionation methods also play a role, along with the physical testing methods, of evaluating heavy oils and residua as refinery feedstocks. For example, by careful selection of an appropriate technique it is possible to obtain a detailed map of feedstock or product composition that can be used for process predictions (Chapter 3). 

The answer to the question as to which products may gained from cmde oils and from refinery residues in which quantities, and by which processes, is an important criterion for the manufacturer. This question may be answered relatively easy for cmde oils using international standardized test methods. Determination of the specific weight of two distilled key fractions allows the nature of the cmde oil to be classified as e.g. paraffin based oil, naphthene-based oil, or mixed base oil [4-4]. Test distillations at atmospheric pressure [4-5 to 4-7] and at reduced pressure (vacuum) [4-6, 4-8, 4-9] can provide the yields of liquid products at an existing refinery lay out. 

Assay analyses of whole crudes are done by combining an atmospheric and vacuum distillation run. These two runs when combined will provide a TBP (True Boiling Point Curve). While these batch distillation methods are labor intensive, taking between three to five days, they allow the collection of distillation fractions that can be utilized for testing. While each of the distillations techniques have been standardized by ASTM, cut schemes tend to mimic Refinery product classifications and there is no standardization of the individual inspection formats. Each corporation tends to perform both physical and chemical testing that best meet the needs of their refining operations and product suites. 

The effect of petroleum chemistry on corrosion lies primarily in its influence on the formation, chemical composition, and characteristics of a liquid water phase, since liquid water in contact with the containing material is a necessary condition for corrosion to occur for the operating temperatures eind pressures encountered in petroleum production. This fact dictates the direction of the discussion on the influence of petroleum chemistry in corrosion testing. This chapter deeds solely with the effects of naturedly occurring petroleum chemistry on corrosion testing and methods to deed with the effects of petroleum chemistry in corrosion testing. There is no elaboration on the actued test techniques except as they etre affected by the petroleum chemistry considerations, and there is no consideration of refinery operations or alterations to the petroleum chemistry used to control corrosion. 

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