Resid conversion

FLEXICOKING™ technology and services are commercially proven to provide a cost-effective, fluidized bed process that thermally converts heavy oils to lighter products and flexigas (a useable fuel) – “Coking without the coke.” Low-cost feeds such as deep-cut vacuum resid, atmospheric resid, oil sands bitumen, heavy whole crudes and DAU, FCC and ebullated-bed bottoms are converted to high-value products through this process.
FLEXICOKING technology with integrated steam/air gasification offers greater flexibility than conventional Delayed Coking, and does it economically. The FLEXICOKING technology not only produces clean liquids of equivalent quantities and similar quality to Delayed Coking, but also gasifies the low-value coke to produce a clean, high-value flexigas that can be used in place of natural gas and conventional fuel gas in refinery processes. Flexigas can also be used to generate electric power and to produce H2, N2 and CO2.

Actualización del gráfico pequeño del proceso de reducción de Flexicoking

Figure 1: Depiction of process flow resulting from FLEXICOKING™ technology and services implementation


  • Full-range products slate: FLEXICOKING technology produces a full range of products, from a C4- reactor gas to C5/975°F (525°C) liquid products, the multipurpose flexigas, and lastly a small stream of low-sulfur coke that is purged to extract feed metals.
  • Proven: Commercially proven for more than 38 years in ExxonMobil and in licensed third-party units. All FLEXICOKING units are operating today at capacities greater than original design for a combined operating capacity of 227 kBd/12 MTA.
  • Flexible: Capable of handling a variety of feeds with a wide range of high Conradson Carbon Residue (CCR), sulfur and heavy metals without the need for a feed furnace.
  • Multipurpose: The high-sulfur, low-value coke is converted to a clean, economical multipurpose flexigas which can be used in refinery furnaces, boilers and gas turbines or processed to recover H2, N2 and CO2.
  • Optimizable: Coke gasification can be optimized on the run, to debottleneck the unit or to satisfy operational requirements such as changes in feed formulations and variations in flexigas consumption.
  • Economic: Integrated “simple” steam/air gasification, carbon steel construction throughout and the absence of feed furnaces are key factors resulting in significantly lower capital investment when compared to Delayed Coking with “complex” oxygen gasification. Expect greater comparative savings in electric power-generation applications (steam or combined cycle).
  • Environmental: Continuous, non-batch operation and closed coke handling system results in low-particulate and fugitive hydrocarbon emissions. Much lower SOx and NOx emissions are produced by burning the clean flexigas, when compared to burning high sulfur coke.
  • Reliable: Continuous, steady state operation in combination with cold-wall carbon steel construction contributes to high reliability and service factors that routinely exceed 92 percent.
  • Reduced plot space: The layout of modern FLEXICOKING units offers reduced plot space – about 20 percent less than that of a basic Delayed Coking unit of similar capacity.

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