Petroleum nitrogen content

Determination of asphaltenes in crude petroleum Nitrogen content BS 2000-143... 

Properties. Pilot-unit data indicate the EDS process may accommodate a wide variety of coal types. Overall process yields from bituminous, subbituminous, and lignite coals, which include Hquids from both Hquefaction and Flexicoking, are shown in Figure 14. The Hquids produced have higher nitrogen contents than are found in similar petroleum fractions. Sulfur contents reflect the sulfur levels of the starting coals ca 4.0 wt % sulfur in the dry bituminous coal 0.5 wt % in the subbituminous and 1.2 wt % sulfur in the dry lignite. 

Kurashov, V. M., Microbiological method of sulfur and nitrogen content decrease in petroleum and hydrogen sulfide in deposit waters and casing-head gases. Patent No. RU2137839. 1999, Sep. 20. 

For the splitting hydrogenation of petroleum gas oil, a lower temperature than that required for the prehydrogenation of bituminous-coal middle oil with smaller conversion to gasoline was sufficient. This is caused mainly by the higher nitrogen content of the bituminous-coal middle oil, which decreases catalyst activity. As shown in Table IV, aromatic rings like naphthalene are saturated with WS2 catalyst at a temperature of 335°C. 

The major question involving burning characteristics of coal liquids relates to the higher nitrogen content compared to petroleum fuel oils and the potential effect on NO emissions. Since NO emissions are sensitive to burning conditions, however, actual burning tests are required under various conditions to assess the effects. 

The shale oil residual had been hydrotreated to a substantial degree, providing it with a hydrogen content very similar to the No. 2 petroleum distillate fuel. The shale oil residual fuel had viscosity characteristics similar to a viscous No. 4 petroleum distillate fuel. The nitrogen content of the hydrotreated shale oil residual was 0.49 weight percent. 

Combustion tests of fuel oil blends derived from the Exxon Donor Solvent (EDS) process were carried out in a laboratory 50 hp test boiler and a commercial 1425 hp boiler. All tests showed that coal derived fuel oils burn cleanly compared to petroleum fuels with low levels of smoke and particulates. Emissions of N0X were related to fuel nitrogen content for both the petroleum and coal-derived fuels. 

The emission results from the combustion tests, along with the PNA analyses of the fuels, are shown in Table II. In agreement with previous work 02,3), particulates and smoke from EDS fuel oil combustion were generally low relative to petroleum fuel oils. N0X emissions tended to be higher due to the higher fuel nitrogen content of EDS fuel oils. 

Primary coal liquids must be upgraded in order to serve these markets. A logical route is to use current black oil conversion technology as practiced in the petroleum industry (2). An applicable UOP process is RCD Unibon (3). This comprises the direct processing of petroleum residues to reduce the sulfur and nitrogen content of heavy fuel oil or to combine desulfurization with conversion of residue to lighter, more valuable products. 

Several processes have been developed for coal liquefaction. Large-scale pilot plants have been in operation for the solvent-refining coal (SRC) process, and a pilot plant is being constructed for the H-Coal process, which is a direct catalytic process. Construction of demonstration plants is under consideration. The coal liquids produced from the current processes contain large amounts of residual fuels. They probably will be used initially as boiler fuels for stationary power plants. However, the nitrogen content of coal liquids is much higher than the petroleum residual fuels. The sulfur contents of coal liquids can vary considerably they depend on the type of coal and the liquefaction process used. Current coal liquefaction processes are capable of produc-... 

Petroleum is recovered from the reservoir mixed with a variety of substances gases, water, and dirt (minerals) (Burris and McKinney, 1992). Thus, refining actually commences with the production of fluids from the well or reservoir and is followed by pretreatment operations that are applied to the crude oil either at the refinery or prior to transportation. Pipeline operators, for instance, are insistent upon the quality of the fluids put into the pipelines therefore, any crude oil to be shipped by pipeline or, for that matter, by any other form of transportation must meet rigid specifications in regard to water and salt content. In some instances, sulfur content, nitrogen content, and viscosity may also be specified. 

Table IV details the characteristics of the middle distillate (400-650 F) charge stocks utilized in this study. The sulfur level of the coal liquid is low at 371-ppm sulfur, while the petroleum liquid shows 3500 ppm and the shale middle distillate analyzed at 7400-ppm sulfur. Nitrogen contents were 1800 ppm for the coal material, 11,400 ppm in the shale liquid, and 31 ppm for the petroleum. Also to be noted for the charge stocks is the wide range of gravities for similar boiling fractions. As was the case with the naphtha charges, these middle distillates contained 1.6-2.6-ppm total metals. The middle distillate charges of coal and shale contained greater than 50% of their nitrogen in the basic form.

The liquid hydrocarbon by-product has a high cyclic content and so is useful as a petroleum refinery feedstock or as a source of aromatic organic chemicals. This material has a relatively high nitrogen content compared with the corresponding petroleum fraction. Its use as a refinery feedstock would require additional nitrogen removal processing by the refinery. 

Chemically speaking, petroleum is an extremely complex mixture of hydrocarbon compounds, with a small amount of oxygen, nitrogen, sulfur, and metal impurities. These impurities result in the degradation of the quality of petroleum and lessen the production ability of available oil resources. Therefore, it is essential to lower the nitrogen content before any refinery processes are performed. 

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