History hydrocarbon conversion

Even if all of the elements described so far have been present within a sedimentary basin an accumulation will not necessarily be encountered. One of the crucial questions in prospect evaluation is about the timing of events. The deformation of strata into a suitable trap has to precede the maturation and migration of petroleum. The reservoir seal must have been intact throughout geologic time. If a leak occurred sometime in the past, the exploration well will only encounter small amounts of residual hydrocarbons. Conversely, a seal such as a fault may have developed early on in the field s history and prevented the migration of hydrocarbons into the structure. 

Thermal reactions of acetylene, butadiene, and benzene result in the production of coke, liquid products, and various gaseous products at temperatures varying from 4500 to 800°C. The relative ratios of these products and the conversions of the feed hydrocarbon were significantly affected in many cases by the materials of construction and by the past history of the tubular reactor used. Higher conversions of acetylene and benzene occurred in the Incoloy 800 reactor than in either the aluminized Incoloy 800 or the Vycor glass reactor. Butadiene conversions were similar in all reactors. The coke that formed on Incoloy 800 from acetylene catalyzed additional coke formation. Methods are suggested for decreasing the rates of coke production in commercial pyrolysis furnaces. 

History Analysis of the 1030 El Monte Trajectory. Because of the relative completeness of initial conditions that we can relate to the Azusa station, we have chosen the 1030 trajectory to discuss in some detail. Examining Table VII, we note an overabundance of ozone at 1030 and a correspondingly rapid completion of NO NO2 conversion. Reactivity analyses (see Atmospheric Adaptation) and our early modeling studies suggest reduction of the oxidation rate constants. To achieve some level of comparative assessment with the previous work, we assign one-fourth the nominal NO flux and one-half the oxidation rate thus, f = 1/4 and r = 1/2 describe the conditions as before. This time, however, we preserve the HC/NOa,-ratio as in the entries in Table VII and reduce hydrocarbon fluxes by a factor of two. This means that the difference in end-point concentrations between this case and the 1/4< no, 1/2< hc entries results solely from the rate constant reduction. This differs from the earlier work where hydrocarbon fluxes were not reduced. 

Consequently the susceptibility to oxidation of elemental carbon depends strongly upon the history of its origin and of the nature of its surface. If the oxidation test of pure hydrocarbons is interrupted after the second reaction step (Fuel Deposition) then a glossy, black, lacquer-like residue will be found in the sample pan. The oxidation of the latter results in heats of combustion in the region of pure carbon. The susceptibdity to oxidation of the coke formed during Fuel Deposition will also be influenced by any residues of the original substances or their conversion products which are still present in the soot. 

As with residence time, the correlating definition of hydrocarbon partial pressure must consider the partial pressure history in the coil. For a given feedstock cracked at a fixed conversion and gas outlet pressure in a pyrolysis coil of a given configuration, the average hydrocarbon partial pressure, PhCA determined by ... 

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