Heavy oils, types

Oil/water interfacial tensions were measured for a number of heavy crude oils at temperatures up to 200°C using the spinning drop technique. The influences of spinning rate, surfactant type and concentration, NaCI and CaCI2 concentrations, and temperature were studied. The heavy oil type and pH (in the presence of surfactant) had little effect on interfacial tensions. Instead, interfacial tensions depended strongly on the surfactant type, temperature, and NaCI and CaCL concentrations. Low interfacial tensions (<0.1 mN/m) were difficult to achieve at elevated temperatures. 

When petroleum occurs in a reservoir that allows the cmde material to be recovered by pumping operations as a free-flowing dark-to-light colored hquid, it is often referred to as conventional petroleum. In some oil fields, the downhole pressure is sufficient for recovery without the need for pumping. Heavy oil differs from conventional petroleum in that its flow properties are reduced and it is much more difficult to recover from the subsurface reservoir. These materials have a much higher viscosity and lower API (American Petroleum Institute) gravity than conventional petroleum, and primary recovery of these petroleum types usually requires thermal stimulation of the reservoir. 

The type of fuel is one of the most important aspects that govern the selection of a gas turbine. Chapter 12 handles the type of fuels and their effect in detail. Natural gas would be the choice of most operators if natural gas was available since its effects on pollution is minimal and maintenance cost would also be the lowest. Table 4-1 shows how the maintenance cost would increase from natural gas to the heavy oils. 

High-temperature corrosion is induced by accelerated reaction rates inherent in any temperature reaction. One phenomenon that occurs frequently in heavy oil-firing boilers is layers of different types of corrosion on one metal surface. 

Fires and explosions that occurred while repairing or demolishing storage tanks containing traces of heavy oil are described in Section 12.4.1 and an explosion of a different type is described at the end of Section 1.1.4. 

A gas processing plant selectively extracts ethylene and ethane from an incoming natural gas mixture stream. These two light hydrocarbons are absorbed in a heavy gasoline type absorber oil, and then stripped with open steam in an open tower. The system data are (see Figure 8-41) ... 

This is very common nowadays to allow bargaining on fuel price or to arrange an interruptible gas tariff, which is backed up at times of peak demand with a stored oil supply. Most types of oil and gas burner are available in dual-fuel form, normally with gas burner design wrapped around the arrangement for oil firing. This is usually the more difficult fuel to burn, particularly in the case of residual heavy oils. Fuel selection is normally by a switch on the burner control panel after isolation has taken place of the non-fired fuel. To avoid the cost and complexity of the fuel preheating on oil firing, smaller systems use gas oil as the standby fuel. 

Most conventional chemical and petrochemical plants do not process many, if any, non-Newtonian fluids. However, polymers, grease, heavy oils, cellulose compounds, paints, fine chalk suspensions in water, some asphalts, and other materials do exhibit one type or another of the characteristics of non-Newtonians, classified as ... 

For results where comparisons could be made, the interfacial tension behavior was practically independent of the type of heavy oil used. Interfacial tensions strongly depended on the surfactant type, temperature, and NaCI and CaCI2 concentrations. Changes in the structure of the amphiphile at the oil/water interface is affected by these variables and accounted for some of the experimental observations. 

Most industrial hydrogen is manufactured by the following hydrocarbon-based oxidative processes steam reforming of light hydrocarbons (e.g., NG and naphtha), POx of heavy oil fractions, and ATR. Each of these technological approaches has numerous modifications depending on the type of feedstock, reactor design, heat input options, by-product treatment,... 

The technical status of conversion processes and relative fuel costs make the extensive reserves of easily accessible coal in the Western Plains key resources that could play an important role in meeting future requirements of petrochemical feedstocks, fuel gas and liquid fuels. And developed concurrently with oil sands and "heaVy" (Lloydminster-type) oil reservoirs, they could allow Canada to regain virtual energy self-sufficiency within a comparatively brief time-frame. 

The effects of composition of heavy oils derived from petroleum and biomass, on their response to cracking over catalysts of various composition were investigated. The contribution to the conversion from different types of cracking was estimated and the effect of temperature on the product distribution was studied. 

The low H/C-ratio of FCC feed derived from liquefied biomass led to low conversion and poor gasoline selectivity. Addition of alumina to the matrix resulted in a catalyst more active for heavy oil cracking but with a poor selectivity. Alumina-montmorillonite catalysts showed activities for heavy oil cracking comparable to that of a conventional, zeolite based, cracking catalyst. Effects of matrix composition and zeolite type on the heavy oil cracking performance are discussed. 

The importance of diffusion enhancement to heavy oil cracking is further illustrated by the alumina-montmorillonite complexes which crack heavier feeds, i.e. Wilmington fraction No. 6, more effectively than REY. When used as matrices for REY, the alumina-montmorillonites results in considerably more active catalysts, at the same zeolite content, compared with a catalyst having a kaolin-binder matrix, while the selectivity properties differs very little between the two types of catalysts (Sterte, 3. Otterstedt, 3-E. Submitted to Appl.Catal.). 

Type 1, Mk 5, P5 (Explosive). A dark-grn expl compn consisting of Amm Picrate 81, ferrosilicon 16, woodpulp 2 heavy oil 1%. 

Type 1 Mk 6, P6. A dark-grn expl compn consisting of Amm Picrate 86, ferrosilicon 11, wood-pulp 2 heavy oil 1%. Its apparent d was 1.13 Brisance 95% PA Expln Temp 450° Impact Sensitivity 13cm (max for no explns with 5-kg wt) Rate of Deton 4620m/sec. Used press-loaded in Depth Charges (Ref 5, p 374)... 

Fixed-bed reactors Trickle-flow reactor (TFR) This is a tubular flow reactor with a concurrent down-flow of gas and liquid over a fixed-bed of catalyst (Figure 3.10). Liquid trickles down whereas the gas phase is continuous. This reactor is mainly used in catalytic applications. Typical application examples of this reactor type are the following HDS of heavy oil fractions and catalytic hydrogenation of aqueous nitrate solutions. 

Plants to produce low-sulfur fuels from coal, oil shale, tar sands or heavy oil frequently are conceived to use the Claus process to produce byproduct sulfur. Often the plant concept imposes unacceptable technical burdens on the Claus section. This paper points out some of the problems, and some solutions. In particular, the paper discusses a Claus type process recently developed with special application to coal and oil gasification plants. 

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