Design and economics for low pressure delayed coking

Technical Report · Fri Jan 01 04:00:00 EST 1993

OSTI ID:7275974

Bansal, B B; Moretta, J C; Gentry, A R ^[1]

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1. M.W. Kellogg Co., Houston, TX (United States)

The current refining trend is to run heavier crudes with a growing emphasis on bottom of the barrel resid upgrading. In general, a reduction in light crude availability and a corresponding increase in the price differential between light and heavy crudes makes the processing of heavier crudes highly attractive. US Department of Energy data indicate that between 1985 and 1989 the average API gravity of crude being processed in the US dropped from 32.46 to 32.14 degrees while the average sulfur content increased 0.15 wt%. As crudes get heavier and the demand for light, clean fuels increases, expanded resid upgrading capacity is rapidly becoming a necessity for most refiners. The coking process has existed since the early 1900's, and delayed coking is still favored as a relatively low cost resid upgrading option. Consistent with the objective of maximizing resid conversion, recent trends in delayed coking include maximizing liquid yields and reducing the production of petroleum coke by operating coke drums at lower pressures. Typically, the incremental liquid gained at lower pressures is worth significantly more than coke and can be further upgraded to lighter products. In addition, the driving force to minimize coke make has been accelerated by the worsening quality of crude oils. As vacuum resid feedstocks become heavier, contaminants in coke such as sulfur and metals are increased, making the coke less marketable. In the case of an existing coker which is capacity limited by coke make, a reduction in coke yield can be quite valuable. This paper discusses the design features and presents the economics associated with building a low pressure delayed coker with a 15 psig coke drum operating pressure versus a more conventional 25 psig design.

• Research Organization: M.W. Kellogg Co., Houston, TX (United States)
• OSTI ID: 7275974
• Report Number(s): AM-93-20
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020400* -- Petroleum-- Processing
CARBONIZATION
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
COKING
COKING PLANTS
DECOMPOSITION
DESIGN
ECONOMICS
ENERGY SOURCES
FOSSIL FUELS
FUELS
INDUSTRIAL PLANTS
LIQUID FUELS
PETROLEUM
PETROLEUM FRACTIONS
PETROLEUM REFINERIES
PETROLEUM RESIDUES
VISCOSITY
YIELDS