Predicting proximity to coke formation
AssigneeThe University of Wyoming Research Corporation
InventorsJohn F. Schabron, Joseph F. Rovani, Jr.
Life of this patent
Estimating the term…
Abstract
Indicia of stability or thresholds of instability may be used to assess the proximity of hydrocarbon materials such as petroleum residua to deposition of carbon rich materials. The invention may be used to evaluate suitability of such hydrocarbon materials to various types of processing methodologies, or to determine processing parameters, either prior to processing or during processing. Prediction of proximity to deposition of carbon rich materials may result in continuous process parameters or increased output, decreased energy use or decreased amount of emissions per unit of such hydrocarbon materials compared to conventional processing technology. Products produced or products processed with this technology may also have a higher level of purity.
Claims32
A method of processing petroleum residua, comprising the steps of:
- a providing an amount of said petroleum residua having solvated asphaltenes dispersed in said petroleum residua;
- b. precipitating an amount of said asphaltenes from said amount of said petroleum residua with a first solvent and determining said amount of precipitated asphaltenes;
- c. dissolving at least part of said amount of said precipitated asphaltenes in a second solvent with a polarity between a polarity of said first solvent and a polarity of a third solvent capable of dissolving said amount of said asphaltenes completely;
- d. determining a proximity to a threshold of instability value of said petroleum residua, wherein said threshold of instability value relates to an amount of said asphaltenes dissolved in said second solvent;
- and
- e. processing said petroleum residua under conditions that maintain a value for said petroleum residua that avoids said threshold of instability value.
A method of analyzing petroleum residua comprising the steps of:
- a. mixing an amount of said petroleum residua Wa into an amount of aromatic solvent Vs;
- b. titrating aromatic solvent soluble components in said amount of aromatic solvent Vs with an amount of weak aliphatic solvent Vt until a flocculation occurs;
- c. calculating a flocculation ratio at infinite dilution FRmax from an equation FRmax=Vs/(Vs+Vt);
- d. calculating a dilution concentration at zero aromatic solvent level Cmin from an equation Cmin=Wa/(Vs+Vt) wherein Vs=0;
- e. determining a peptizability of asphaltenes pa from an equation pa=1−FRmax;
- and
- f determining a value of pa/Cmin.
A method of processing petroleum residua comprising the steps of
- a. providing an amount of said petroleum residua Wa having solvated asphaltenes dispersed in said petroleum residua;
- a. mixing said amount of said petroleum residua Wa into an amount of aromatic solvent Vs;
- b. titrating aromatic solvent soluble components in said amount of aromatic solvent Vs with an amount of weak aliphatic solvent Vt until a flocculation occurs,
- d. determining a proximity to a threshold of instability value of said petroleum residua, as a result of said steps (a) of providing an amount of said petroleum residua Wa having solvated asphaltenes dispersed in said petroleum residua and (b) of mixing said amount of said petroleum residua Wa into an amount of aromatic solvent Vs, utilizing a value of KF, wherein KF is a ratio of an average size of a plurality of solvated core materials with an associated solvent to an average size of a plurality of solvated core materials, thus representing an amount of said associated solvent associated with said plurality of solvated core materials;
- and
- e. processing said petroleum residua under conditions that maintain KF equal to or greater than about 1.4.
Dependencies are inferred from the claim text.