Methodology to determine feed quality (di+ring aromatic content) of FCC and hydrocracking feeds

1. A method comprising:

upgrading naphtha and diesel yields from fluid catalytic cracking and hydrocracking units by improving a feed quality of a petroleum feedstock, product or fraction mixture;

wherein improving the feed quality of the petroleum feedstock, product or fraction mixture occurs by:

determining an API Gravity of the petroleum feedstock, product or fraction mixture;

determining a temperature at which about fifty percent of the petroleum feedstock, product or fraction mixture boils (T 50 ); and

estimating a feed quality for the petroleum feedstock, product or fraction mixture as determined from the API Gravity and the T 50 for the feedstock, product or fraction mixture,

wherein the estimating the feed quality is performed by:

i. calculating a first empirical expression of the form:

Di +Ring Aromatic Content (%)= A*API (° API )+ B*T 50 (° F.)+ C,

wherein Di+Ring Aromatic Content is the feed quality (%) of the petroleum feedstock, product or fraction, API is the API Gravity (° API) of the petroleum feedstock, product or fraction mixture, and T 50 is the temperature (° F.) at which about fifty percent of the petroleum feedstock, product or fraction boils; and wherein A is a first coefficient, B is a second coefficient and C is a third coefficient;

ii. plotting a trendline from a data set, wherein the trendline is in the form:

Di +Ring Aromatic Content (%)= A′*API (° API )+ B′*T 50 (° F.)+ C′,

wherein A′ is a potential first coefficient, B′ is a potential second coefficient, and C′ is a potential third coefficient; and adjusting one or more coefficients of the first empirical expression to improve the feed quality estimate;

iii. improving upon the first empirical expression by calculating a second empirical expression of the form:

Conversion (wt %) = D *( Di +Ring Aromatic Content) (wt %) + E,

wherein Conversion is the FCC or hydrocracking conversion (wt %) of the petroleum feedstock, product or fraction mixture, and Di+Ring Aromatic Content is the feed quality (wt %) of the petroleum feedstock, product or fraction; and wherein D is a fourth coefficient, and E is a fifth coefficient;

iv. plotting an improved trendline from a data set, wherein the improved trendline is in the form:

Conversion (wt %)= D ′*( Di +Ring Aromatic Content) (wt %)+ E′,

wherein D′ is a potential fourth coefficient, and E′ is a potential fifth coefficient; and

v. adjusting one or more coefficients in the second empirical expression to improve the conversion estimate,

adjusting the petroleum feedstock, product or fraction mixture to achieve a higher feed quality;

wherein the API Gravity is determined using a density analyzer; and

further comprising comparing one or more feed quality estimates as determined from API Gravity and T 50 to a corresponding feed quality measurement as determined by high pressure liquid chromatography.

2. A method comprising:

a) determining an API Gravity of a petroleum feedstock, product or fraction mixture;

b) determining a temperature at which about fifty percent of the petroleum feedstock, product or fraction boils (T 50 ); and

c) estimating a feed quality for the petroleum feedstock, product or fraction mixture as determined from the API Gravity and the T 50 for the feedstock, product or fraction,

wherein the estimation of the feed quality is performed in a computer-readable medium having thereon a plurality of instructions, wherein the plurality of instructions when executed by a processor cause the processor to:

i. calculate using a first empirical expression of the form:

Di+Ring Aromatic Content (%)= A*API (° API )+ B*T 50 (° F.)+ C,

wherein Di+Ring Aromatic Content is the feed quality (%) of the petroleum feedstock, product or fraction mixture, API is the API Gravity (° API) of the petroleum feedstock, product or fraction, and T 50 is the temperature (° F.) at which about fifty percent of the petroleum feedstock, product or fraction mixture boils; and wherein A is a first coefficient, B is a second coefficient and C is a third coefficient;

ii. plotting a trendline from a data set, wherein the trendline is in the form:

Di +Ring Aromatic Content (%)= A′*API (° API )+ B′*T 50 (° F.)+C′,

wherein A′ is a potential first coefficient, B′ is a potential second coefficient, and C′ is a potential third coefficient; and adjusting one or more coefficients of the first empirical expression to improve the feed quality estimate;

iii. improving upon the first empirical expression by calculating a second empirical expression of the form:

Conversion (wt %)= D *( Di +Ring Aromatic Content) (wt %)+E,

wherein Conversion is the FCC or hydrocracking conversion (wt %) of the petroleum feedstock, product or fraction, and Di+Ring Aromatic Content is the feed quality (wt %) of the petroleum feedstock, product or fraction mixture; and wherein D is a fourth coefficient, and E is a fifth coefficient; and

iv. plotting an improved trendline from a data set, wherein the improved trendline is in the form:

Conversion (wt %)= D ′*( Di +Ring Aromatic Content) (wt %)+ E′,

wherein D′ is a potential fourth coefficient, and E′ is a potential fifth coefficient; and

v. adjusting one or more coefficients in the second empirical expression to improve the conversion estimate;

wherein the API Gravity is determined using a density analyzer; and

further comprising comparing one or more feed quality estimates as determined from API Gravity and T 50 to a corresponding feed quality measurement as determined by high pressure liquid chromatography.