Abstract:
Methods of extracting and enriching high value pentane streams suitable for adding to refinery grade gasoline are provided by balancing the relative amounts of isopentane and n-pentane in the output stream of a depentanizer tower, and by balancing the sulfur fractions in the input and output streams of the tower.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/081,687, entitled “Methods For Splitting Mixed Hydrocarbon Streams,” filed on Nov. 19, 2014, which is incorporated herein by reference in its entirety as if fully set forth below. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to mixed hydrocarbon streams, particularly liquid gasoline streams extracted from natural gasoline wells, and to methods of splitting those streams into defined product streams, including an overhead pentane stream with defined ratios of n-pentane to isopentane, and a bottoms stream comprising heavier hydrocarbons. 
       BACKGROUND OF THE INVENTION 
       [0003]    Hydraulic finking has tapped into enormous volumes of energy reserves in North America, but it has also resulted in the production of large volumes of NGLs and lesser value streams that have limited industrial utility and market applications. The production of liquid gasoline, for example, has increased dramatically as natural gas is extracted from hydraulic fracking wells. 
         [0004]    Liquid extracted from natural gas deposits (natural gas liquids or NGLs) typically consists of several hydrocarbon components of differing value and industrial utility. Common NGL products are ethane (C 2 H 6 ), propane (C 3 H 8 ), butanes (iC 4 H 10  and nC 4 H 10 ) and natural gasoline (C 5+ ). Natural gasoline, sometimes known as condensate or naphtha, refers to the pentanes and heavier components in a natural gas stream, and usually is primarily made up of straight and branched chain paraffins. Natural gasoline is most commonly used as refinery feedstock, although it can also be used as a petrochemical feedstock. 
         [0005]    One potential use for NGLs is as a hydrocarbon feedstock for the production of refinery-grade gasoline, and numerous publications have proposed using the components of NGLs in this manner. For example, several publications, including U.S. Pat. Nos. 6,679,302, 7,631,671 and 8,192,510 to Mattingly and Vanderbur, have described the use of butane to expand refinery grade gasoline downstream of the refinery. Butane is especially useful in these blending operations because of its consistent physical contribution to volatility and octane in a blended gasoline pool. 
         [0006]    U.S. Pat. Nos. 7,456,328 and 7,741,525 teach methods for blending propane into an ethane containing stream to increase the vapor pressure of the ethane, thereby allowing for production of an “on-spec” propane product stream while at the same time maximizing the value of the ethane stream. 
         [0007]    The mixed pentanes derived from NGL and natural gasoline streams have found less market applications and industrial utility than their lighter counterparts due in large part to the variability in pentane&#39;s hydrocarbon content, and uncertainty about how much impact this inconsistency will have on the volatility and octane of a hydrocarbon stream with which the pentanes are mixed. This is especially true for pentane streams that contain large amounts of n-pentane, which has a neat octane value of only 65, and whose effect on fuel octane is variable and uncertain. The following table summarizes relevant physical properties associated with pentane when blended into gasoline: 
         [0000]                                                                                          Neat    Blending           Boiling           Octane   Octane           Pt       TV/L =   (R +   (R +           (° F.)   RVP   20   M/2)   M/2)                                n-butane   31   55   negative   92   92       n-pentane   97   16   87   65   &gt;65       neopentane   49   20   50   83   &gt;83       isopentane   82   35   1   91   91                    
As can be seen, the addition of n-pentane to a gasoline stream, or the addition of mixed pentanes that include n-pentane, could be expected to significantly and negatively impact the octane value of the gasoline stream, given the low blending octane value of n-pentane.
 
       SUMMARY OF THE INVENTION 
       [0008]    Methods for splitting low-value natural gasoline streams have now been developed that produce pentane streams with defined n-pentane and isopentane ratios. As long as the ratio of n-pentane to isopentane is controlled in the splitting operation, these pentane streams, which have previously been considered low value by-products of natural gasoline, can be added to refined gasoline without negatively impacting the octane value of the gasoline, thereby greatly increasing the value of the pentanes. It has been experimentally found that these mixed pentanes can be added to gasoline in proportions as high as 15 or even 20% (i.e. 15 or 20 parts pentanes to 85 or 80 parts gasoline). 
         [0009]    The methods partly depend on the discovery that isopentane can effectively offset the low blending octane value of n-pentane when defined isopentane:n-pentane ratios are observed in the production of the mixed pentane stream. The methods also depend on the discovery that the natural gasoline streams from fracking operations lend themselves to these operations, such that mixed pentanes meeting defined isopentane:n-pentane ratios can be split from the natural gasoline using a suitably designed depentanizer. 
         [0010]    Therefore, in a first embodiment the invention provides a method of making mixed pentanes comprising: (a) providing a natural gasoline stream comprising: (i) 0 wt % methane or ethane or propane; (ii) from 0 to 5.0 wt % butane; (iii) from 5 to 80 wt % isopentane; (iv) from 5 to 80 wt % normal pentane; and (v) from 10 to 90 wt % of hydrocarbons consisting of 6 or more carbon atoms (C 6+  hydrocarbons); (b) splitting said natural gasoline stream into a bottom stream and an enriched overhead pentane stream comprising: (i) greater than 95 wt % of said butane in said natural gasoline stream; (ii) greater than 95 wt % of said isopentane in said natural gasoline stream; (iii) greater than 95 wt % of said normal pentane in said natural gasoline stream; and (iv) from 0 to 20 wt % of said C 6+  hydrocarbons in said natural gasoline stream; and (c) recovering said enriched overhead pentane stream. 
         [0011]    As shown in  FIG. 1 , these methods are preferably performed in a suitably designed depentanizer distillation column in which the higher volatility pentanes are withdrawn from the top of the tower and the lower volatility heavier hydrocarbons are withdrawn from the bottom of the tower. In a particularly preferred embodiment, the mixed pentanes produced by the methods of the present invention are suitable for mixing into a refined gasoline stream meeting applicable ASTM specifications. 
         [0012]    A second principal embodiment relates to the enriched pentane produced by the methods of the present invention. Thus, in another embodiment the invention provides an enriched pentane stream suitable for mixing into a refined gasoline stream meeting ASTM D4814-13b made by the process of the first principal embodiment or any subembodiment thereof. 
         [0013]    In yet another principal embodiment the invention provides an enriched pentane stream suitable for mixing into a refined gasoline stream meeting ASTM D4814-13b comprising: a) 0 wt % methane or ethane or propane; b) from 0.01 to 5 wt % butane; c) from 30 to 70 wt % isopentane; d) from 30 to 70 wt % normal pentane; and e) from (0.01 to 5 wt % hydrocarbons having 6 or more carbons. 
         [0014]    Additional advantages of the invention are set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed. 
     
    
     
       DESCRIPTION OF THE FIGURES 
         [0015]      FIG. 1  depicts a representative system of the present invention for splitting a natural gasoline stream into a mixed pentane stream that contains isopentane and n-pentane at designated ratios. 
       
    
    
     DETAILED DESCRIPTION 
     Definitions and Use of Terms 
       [0016]    “ASTM” refers to the American Society for Testing and Materials. Unless otherwise indicated, when reference is made to an ASTM standard herein, it is made in reference to the ASTM standard in effect on Oct. 1, 2012, and the ASTM standard is incorporated herein by reference. 
         [0017]    “Butane” refers to isobutane and n-butane and mixtures thereof, but preferably refers to n-butane. 
         [0018]    “Certified gasoline” is fuel meeting the standards of ASTM Standard Specification Number D 4814-01a (“ASTM 4814”), and should be distinguished from in-process gasoline streams at a refinery that have not been released from the refinery and have not been certified. The specifications for different types of gasoline set forth in ASTM 4814 vary based on a number of parameters affecting volatility and combustion such as weather, season, geographic location and altitude. For this reason, gasoline types produced in accordance with ASTM 4814 are broken down into volatility categories AA, A, B, C, D and E, and vapor lock protection categories 1, 2, 3, 4, 5, and 6, each category having a set of specifications. Certified gasoline also includes a gasoline certified to meet ASTM 4814 upon the addition of a designated quantity of ethanol. 
         [0019]    “Hydrocarbon” refers to any linear, branched, or cyclic molecule, aliphatic or aromatic, saturated or unsaturated, composed primarily of hydrogen and carbon. 
         [0020]    The enriched pentane stream of the present invention will comprise “mixed pentanes,” referring to a stream or pool of pentanes that contains n-pentane in addition to isopentane. The stream or pool might also contain neopentane, although this compound is quite rare in natural supplies. The pentanes preferably make up at least 10%, 30%, 50%, 70%, 90% or 95% of the enriched pentane stream. The pentanes can be present in an ratio that satisfies the performance requirements of this invention, but preferably contain front 20% of 30% up to 100% isopentane, with the balance being n-pentane. In any of the various embodiments and subembodiments discussed herein, the mixed pentanes can be characterized by a minimum ratio of isopentane to n-pentane of 1:5, 2:5, 3:5, 4:5, 5:5, 10:5, or greater, an isopentane to n-pentane ratio of from 30:70 to 95:5, from 30:70 to 60:40, or an isopentane to n-pentane ratio of from 40:60 to 50:50. 
         [0021]    Ratios, quantities and rates of liquid flows expressed herein, unless otherwise specified, are expressed in terms of volume, and are preferably measured at room temperature (25° C.) and atmospheric pressure. 
         [0022]    When the singular forms “a,” “an” and “the” or like terms are used herein, they will be understood to include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a hydrocarbon” includes mixtures of two or more such hydrocarbons, and the like. The word “or” or like terms as used herein means any one member of a particular list and also includes any combination of members of that list. 
         [0023]    Throughout the description and claims of this specification, the word “comprise” and variations of the word, such as “comprising” and “comprises,” means “including but not limited to,” and is not intended to exclude, for example, other additives, components, integers or steps. 
         [0024]    When ranges are given by specifying the lower end of a range separately from the upper end of the range, it will be understood that the range can be defined by selectively combining any one of the lower end variables with any one (If the upper end variables that is mathematically possible. 
         [0025]    The invention is defined in terms of three principal embodiments. When an embodiment or subembodiment other than the principal embodiment is discussed herein, it will be understood that the embodiment or subembodiment can be applied to farther limit any three of the principal embodiments. 
       Discussion 
       [0026]    As mentioned above, the invention is based on the discovery that isopentane overcomes the negative effects of n-pentane on blend octane values when the two pentanes are present in defined ratios, the discovery that natural gasoline streams coming onto the market are suitable for producing such mixed pentanes, and the development of processes for splitting mixed pentanes from the natural gasoline stream to ensure that the mixed pentanes withdrawn from the top of the depentanizer properly balance the ratio of isopentane and n-pentane. 
         [0027]    In a first principal embodiment the invention provides a method of making pentanes suitable for mixing into a refined gasoline stream meeting applicable ASTM specifications comprising: a) providing a natural gasoline stream comprising: i) 0 wt % methane or ethane or propane; ii) from 0, 0.01, or 0.1 wt % to 5.0, 1.5, or 0.5 wt % butane; iii) from 5, 10 or 15 to 80, 50 or 35 wt % isopentane; iv) from 5, 10 or 15 to 80, 50 or 35 wt % normal pentane; and v) from 10, 20 or 30 to 90, 80 or 70 wt % hydrocarbons consisting of 6 or more carbon atoms (C 6+  hydrocarbons); b) splitting said natural gasoline stream into a bottom stream and an enriched overhead pentane stream comprising: i) greater than 95, 98, or 99.5 wt % of said butane in said natural gasoline stream; ii) greater than 95, 97, or 9 wt % of said isopentane in said natural gasoline stream; iii) greater than 95, 97 or 98 wt % of said normal pentane in said natural gasoline stream; and iv) from 0, 0.01, or 0.1 wt % to 20, 5, or 2 wt % of said C 6+  hydrocarbons in said natural gasoline stream; and c) recovering said enriched overhead pentane stream. 
         [0028]    The methods of the present invention can be performed according to traditional distillation techniques described in the prior art including Henry Z. Kister, Chemical engineering: Distillation design McGraw-Hill 1992 (1 st  Edition). In a preferred embodiment the method comprises splitting said natural gasoline stream into an enriched overhead pentane stream in a distillation column comprising from 15 to 70 trays having a tray efficiency of greater than 80%. Particular methods for performing the methods are described in the examples and  FIG. 1  hereto. 
         [0029]    In a particular subembodiment of the methods of this invention, (a) the natural gasoline stream comprises (i) from 0.01 to 1.5 wt % butane; from 10 to 50 wt % isopentane; (iii) from 10 to 50 wt % normal pentane; and (iv) from 20 to 80 wt % C 6+  hydrocarbons; (b) said enriched overhead pentane flow comprises (i) greater than 98 wt % of said butane in said natural gasoline stream; (greater than 97 wt % of said isopentane in said natural gasoline stream; (iii) greater than 97 wt % of said normal pentane in said natural gasoline stream; and (iv) from 0.1 to 5 wt % of said C 6+  hydrocarbons in said natural gasoline stream. 
         [0030]    In another particular subembodiment of the methods of the invention: (a) said natural gasoline comprises (i) from 0 to 0.5 wt % butane, (ii) from 15 to 35 wt % isopentane: (iii) from 15 to 35 wt % normal pentane; and (iv) from 30 to 70 wt % C 6+  hydrocarbons; and (b) said enriched isopentane flow comprises (i) greater than 99.5 wt % of said butane in said natural gasoline stream; (ii) greater than 98 wt % of said isopentane in said natural gasoline stream; (iii) greater than 98 wt % of said normal pentane in said natural gasoline stream; and (iii) from 0.01 to 2 wt of said C 6+  hydrocarbons in said natural gasoline stream. 
         [0031]    Another subembodiment depends on the control of olefinic and aromatic compounds in the input stream, and in this subembodiment the natural gasoline stream comprises less than 5 or 2 wt % of olefinic and aromatic compounds. 
         [0032]    Yet another subembodiment relates to the use of the method to control sulfur compounds in the final product. In this subembodiment, (a) said liquid gasoline stream comprises from 5, 10 or 15 to 50, 40 or 30 ppm sulfur compounds; (b) said enriched overhead pentane stream comprises less than 60, 40, or 20 of said sulfur compounds in said liquid gasoline stream; and (c) said enriched overhead pentane stream comprises greater than 1 or 2 and less than 30 or 10 ppm sulfur compounds. Exemplary sulfur containing compounds include hydrogen sulfide (H 2 S), carbonyl sulfide (COS), methyl mercaptan (MeSH), ethyl mercaptan (EtSH), carbon disulfide (CS 2 ), isopropyl mercaptan (iC3SH), and isobutyl mercaptan (iC 4 SH). 
         [0033]    In another subembodiment, (a) said liquid gasoline stream comprises from 10 to 30 ppm sulfur compounds; and (h) said enriched pentane stream comprises greater than 1 and less than 10 ppm sulfur compounds. In still another subembodiment a) said liquid gasoline stream comprises from 15 to 40 ppm sulfur containing compounds; and (c) said enriched pentane stream comprises greater than 1 and less than 10 ppm sulfur compounds. In either embodiment, the enriched overhead pentane stream preferably comprises less than 40, 50 or 60% of the sulfur compounds in the natural gasoline stream. 
         [0034]    Another principal embodiment relates to the pentane stream produced by any of the foregoing embodiments. Therefore, the invention also provides an enriched pentane stream suitable for mixing into a refined gasoline stream meeting ASTM D4814-13b made by the process of any of the foregoing embodiments or subembodiments. 
         [0035]    Another principal embodiment relates to the novelty of the pentane stream produced the foregoing embodiments. In this embodiment the invention provides an enriched pentane stream suitable for mixing into a refined gasoline stream meeting ASTM D4814-13b comprising: a) 0 wt % methane or ethane or propane; b) from 0.01 to 5 wt % butane; c) from 30 to 70 wt % isopentane; d) from 30 to 70 wt % normal pentane; and e) from 0.01 to 5 wt % hydrocarbons having 6 or more carbons. In one subembodiment the enriched pentane stream comprises greater than 1 or 2 ppm and less than 10 or 30 ppm sulfur containing compounds. In another subembodiment the enriched pentane stream comprises greater than 1 ppm and less than 10 ppm sulfur containing compounds. 
       EXAMPLES 
       [0036]    The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how the methods claimed herein are made and evaluated, and are intended to be purely exemplary of the invention and are not intended to limit the scope of what the inventor regards as his invention. Efforts have been made to ensure accuracy with respect to numbers (e.g., amounts, temperature, etc.) but some errors and deviations should be accounted for. 
       Example 1 
     Case Study of Depentanizer Tower Performance at Various Conditions 
       [0037]    A simulation study was undertaken to evaluate the impact of various operating parameters on the performance of a depentanizing tower, and the ability of the depentanizing tower to produce mixed pentanes meeting the specifications described in the instant specification. The results are presented in Tables 1.a and 1.b. 
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 1.a 
               
             
             
               
                   
               
               
                 Case Study of Sunoco Tower Depentanizer Performance at Various Conditions 
               
             
          
           
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                 Case 8 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                 (Note 3) 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                 Soluble 
               
               
                   
                   
                 Case 1 
                   
                   
                   
                   
                   
                 Case 7 
                 H2O,  
               
               
                   
                   
                 Original 
                 Case 2 
                 Case 3 
                 Case 4 
                 Case 5 
                   
                 (Note 2) 
                 2 vol % 
               
               
                   
                   
                 0.2 vol % 
                 0.1 vol % 
                 Soluble 
                 Soluble 
                 Soluble 
                 Case 6 
                 Soluble 
                 Butane 
               
               
                   
                   
                 H2O, 
                 H2O,  
                 H2O, 
                 H2O,  
                 H2O,  
                 Soluble 
                 H2O,  
                 (Increase 
               
               
                   
                   
                 2 vol % 
                 2 vol % 
                 2 vol % 
                 1 vol % 
                 0.5 vol % 
                 H2O, 0% 
                 2 vol % 
                 reboiler 
               
               
                 Title 
                   
                 Butane 
                 Butane 
                 Butane 
                 Butane 
                 Butane 
                 Butane 
                 Butane 
                 duty) 
               
               
                 Property 
                 Units 
                 Value 
                 Value 
                 New Base 
                 Value 
                 Value 
                 Value 
                 Value 
                 Value 
               
               
                   
               
             
          
           
               
                 TOWER 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 PERFORMANCE 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 C5 Recovery 
                 vol % 
                 97.0% 
                 97.0% 
                 97.0% 
                 97.0% 
                 97.0% 
                 97.0% 
                 97.0% 
                 99.7% 
               
               
                 C5 Purity 
                 vol % 
                 96.0% 
                 96.0% 
                 96.0% 
                 96.0% 
                 96.0% 
                 96.0% 
                 96.0% 
                 96.0% 
               
               
                 Free water from 
                 lb/hr 
                 577 
                 278 
                 22 
                 22 
                 22 
                 22 
                 22 
                 22 
               
               
                 Overhead Drum 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Feed/Btms Exchanger 
                 MM Btu/hr 
                 5.16 
                 5.16 
                 5.16 
                 5.16 
                 5.16 
                 5.16 
                 5.16 
                 5.16 
               
               
                 Duty 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Reboiler Duty 
                 MM Btu/hr 
                 45.2 
                 45.2 
                 45.2 
                 36.7 
                 35.5 
                 34.6 
                 48.4 
                 60 
               
               
                 FEED 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Temp of Feed 
                 Deg F. 
                 100 
                 100 
                 100 
                 100 
                 100 
                 100 
                 60 
                 100 
               
               
                 RVP of Feed 
                 psia 
                 13.6 
                 13.6 
                 13.6 
                 13.1 
                 12.9 
                 12.6 
                 12.6 
                 13.6 
               
               
                 TVP of Feed 
                 psia 
                 14.1 
                 14.1 
                 14.1 
                 13.6 
                 13.3 
                 13.0 
                 6.2 
                 14.1 
               
               
                 TVP of Feed @ 60 F. 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Water in Feed 
                 vol %  
                 0.200% 
                 0.102% 
                 0.015% 
                 0.015% 
                 0.015% 
                 0.015% 
                 0.015% 
                 0.015% 
               
               
                 Free water in Feed 
                 lb/hr 
                 555 
                 256 
                 0 
                 0 
                 0 
                 0 
                 0 
                   
               
               
                 Total water in Feed 
                 lb/hr 
                 600 
                 300 
                 44 
                 44 
                 44 
                 45 
                 44 
                 44 
               
               
                 nC4 in Feed 
                 vol % 
                 2.0% 
                 1.0% 
                 2.0% 
                 1.0% 
                 0.5% 
                 0.0% 
                 2.0% 
                 2.0% 
               
               
                 C5 PRODUCT 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Temp of C5 Product 
                 Deg F. 
                 100 
                 100 
                 100 
                 100 
                 100 
                 100 
                 100 
                 100 
               
               
                 nC4 in C5 Product 
                 vol % 
                 3.53 
                 3.53 
                 3.53 
                 1.77 
                 0.88 
                 0.00 
                 3.53 
                 3.44 
               
               
                 RVP of C5 Product 
                 paia 
                 19.4 
                 19.4 
                 19.4 
                 18.6 
                 18.2 
                 17.9 
                 19.4 
                 19.1 
               
               
                 TVP of C5 Product 
                 psia 
                 20.3 
                 20.3 
                 20.3 
                 19.4 
                 18.9 
                 18.4 
                 20.3 
                 20.2 
               
               
                 Cases 3 through 5 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 have only soluble 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 water in the feed. 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 TVP of C5 Product as 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 a function of 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 temperature for the 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 case of 2 lv % nC4 in 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 the feed (Note 1). 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Temperature 
                 Deg F. 
                 90 
                 100 
                 120 
                 130 
                   
                   
                   
                   
               
               
                 Pressure 
                 psia 
                 16.8 
                 20.3 
                 31.3 
                 33.9 
               
               
                   
               
               
                 Note 1: 
               
               
                 The RVP of the CS product is not a function of temperature since it represents the vapor pressure at a given temperature of 100 F. 
               
               
                 Note 2: 
               
               
                 Temperature of Feed = 100 F. except for Case 7 where it is 60 F. 
               
               
                 Note 3: 
               
               
                 Reboiler duty for Case 8 is set at 60 MM Btu/hr which improves the % recovery of the C5s. 
               
             
          
         
       
     
         [0000]    
       
         
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 1.b 
               
               
                   
               
               
                 Case 1 
                 Case 2 
                 Case 3 
                 Case 4 
                 Case 5 
                 Case 6 
                   
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 577 
                 278 
                 22 
                 22 
                 22 
                 22 
                 Water from 
               
               
                   
                   
                   
                   
                   
                   
                 Ovhd Drum 
               
               
                 45,564,222 
                 45,409,652 
                 45,186,302 
                 36,676,087 
                 35,527,629 
                 34,626,371 
                 Reboiler Duty 
               
               
                 13.6 
                 13.6 
                 13.6 
                 13.1 
                 12.9 
                 12.6 
                 RVP of Feed 
               
               
                 14.1 
                 14.1 
                 14.1 
                 13.6 
                 13.3 
                 13.0 
                 TVP of Feed 
               
               
                 600.0 
                 300.3 
                 44.3 
                 44.7 
                 44.9 
                 45.1 
                 Water in Feed 
               
               
                 0.0020439 
                 0.001023 
                 0.000151105 
                 0.000152455 
                 0.000153138 
                 1.54E−04 
                 vol frac water  
               
               
                   
                   
                   
                   
                   
                   
                 in feed 
               
               
                 100 
                 100 
                 100 
                 100 
                 100 
                 1.00E+02 
                 Temp of C5 
               
               
                   
                   
                   
                   
                   
                   
                 Product 
               
               
                 19.4 
                 19.4 
                 19.4 
                 18.6 
                 18.2 
                 17.9 
                 RVP of C5 
               
               
                   
                   
                   
                   
                   
                   
                 Product 
               
               
                 20.1 
                 20.3 
                 20.3 
                 19.4 
                 18.9 
                 18.4 
                 TVP of C5 
               
               
                   
                   
                   
                   
                   
                   
                 Product 
               
               
                 0.0353 
                 0.0353 
                 0.0353 
                 0.0177 
                 0.0088 
                 0.0000 
                 vol fr nC4 in C5 
               
               
                   
                   
                   
                   
                   
                   
                 Product 
               
               
                 0.020 
                 0.020 
                 0.0199 
                 0.009948431 
                 0.004974212 
                 0.00E+00 
                 vol frac nC4 in 
               
               
                   
                   
                   
                   
                   
                   
                 Feed 
               
               
                   
               
             
          
         
       
     
       Example 2 
     Simulation of Depentanizer and Associated Streams Under Optimized Conditions 
       [0038]    The pentane splitting operation depicted in  FIG. 1  was simulated using a set of assumed operating conditions to determine the overall properties of the process streams, including the natural gasoline input to the depentanizer, the mixed pentane stream withdrawn from the top of the depentanizer, and the heavy hydrocarbon stream withdrawn from the bottom of the depentanizer. The properties and content of the various streams depicted in  FIG. 1  are given in Tables 2.a and 2.b. 
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 2.a 
               
             
             
               
                   
               
               
                 Properties of Streams 1-9 
               
             
          
           
               
                   
                 1 
                 2 
                 3 
                 4 
                   
                 6 
                 7 
                   
                   
               
               
                 Stream Number 
                 Natural 
                 Preheated 
                 Tower 
                 Tower 
                 5 
                 PURITY 
                 Liquid 
                 8 
                 9 
               
               
                   
                 Gasoline to 
                 Natural 
                 Overhead 
                 Overhead 
                 Tower 
                 C5s to 
                 to 
                 Reboiler 
                 Tower 
               
               
                 Stream Description 
                 Fractionator 
                 Gasoline 
                 Vapor 
                 Liquid 
                 Reflux 
                 Storage 
                 Reboiler 
                 Boilup 
                 Bottoms 
               
               
                   
               
             
          
           
               
                 Overall Properties 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Pressure, psig 
                 200 
                 45 
                 30 
                 30 
                 30 
                 30 
                 40 
                 40 
                 40 
               
               
                 Temperature, ° F. 
                 97 
                 162 
                 155 
                 100 
                 105 
                 105 
                 241 
                 254 
                 254 
               
               
                 Std. Vol Flow (V), 
                 — 
                 — 
                 32.6 
                 — 
                 — 
                 — 
                 — 
                 34.3 
                 — 
               
               
                 MMSCFD 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Std. Vol Flow (L), 
                 19,959 
                 19,959 
                 — 
                 27,682 
                 16,446 
                 11,237 
                 40,912 
                 — 
                 8,722 
               
               
                 barrel/day 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Mass Flow, lb/hr 
                 193,635 
                 193,635 
                 254,370 
                 254,370 
                 150,776 
                 103,021 
                 415,923 
                 325,882 
                 90,041 
               
               
                 Mole Flow, 
                 2,460 
                 2,460 
                 3,581 
                 3,581 
                 2,109 
                 1,441 
                 4,758 
                 3,770 
                 987 
               
               
                 lbmole/hr 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Vapor Weight 
                 0.00 
                 0.00 
                 1.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 1.00 
                 0.00 
               
               
                 Fraction 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Vapor Mole 
                 0.00 
                 0.00 
                 1.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 1.00 
                 0.00 
               
               
                 Fraction 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Enthalpy Flow, 
                 −185.2 
                 −178.2 
                 −221.3 
                 −264.8 
                 −154.6 
                 −105.6 
                 −323.7 
                 −212.3 
                 −67.4 
               
               
                 MMBtu/hr 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Composition, liq. 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 vol % 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 H2O 
                 0.20 
                 0.20 
                 0.16 
                 0.16 
                 0.01 
                 0.01 
                 0.00 
                 0.00 
                 0.00 
               
               
                 N-Butane 
                 1.99 
                 1.99 
                 3.53 
                 3.53 
                 3.53 
                 3.53 
                 0.00 
                 0.00 
                 0.00 
               
               
                 4O 
                 0.03 
                 0.03 
                 0.05 
                 0.05 
                 0.05 
                 0.05 
                 0.00 
                 0.00 
                 0.00 
               
               
                 N-Pentane 
                 28.36 
                 28.36 
                 48.60 
                 48.60 
                 48.67 
                 48.67 
                 4.55 
                 5.16 
                 2.31 
               
               
                 Isopentane 
                 25.58 
                 25.58 
                 45.33 
                 45.33 
                 45.39 
                 45.39 
                 0.30 
                 0.33 
                 0.16 
               
               
                 Cyclopentane 
                 1.67 
                 1.67 
                 1.93 
                 1.93 
                 1.93 
                 1.93 
                 2.31 
                 2.57 
                 1.33 
               
               
                 5O 
                 0.06 
                 0.06 
                 0.11 
                 0.11 
                 0.11 
                 0.11 
                 0.01 
                 0.01 
                 0.00 
               
               
                 Hexane 
                 9.51 
                 9.51 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 24.07 
                 24.68 
                 21.81 
               
               
                 Benzene 
                 1.13 
                 1.13 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 2.99 
                 3.10 
                 2.58 
               
               
                 22 Methylbutane 
                 0.41 
                 0.41 
                 0.15 
                 0.15 
                 0.15 
                 0.15 
                 1.20 
                 1.32 
                 0.75 
               
               
                 23 Methylbutane 
                 0.90 
                 0.90 
                 0.02 
                 0.02 
                 0.02 
                 0.02 
                 2.76 
                 2.95 
                 2.04 
               
               
                 2 Methylpentane 
                 6.25 
                 6.25 
                 0.09 
                 0.09 
                 0.09 
                 0.09 
                 19.16 
                 20.50 
                 14.22 
               
               
                 3 Methylpentane 
                 3.24 
                 3.24 
                 0.01 
                 0.01 
                 0.01 
                 0.01 
                 9.43 
                 9.98 
                 7.41 
               
               
                 Methylcyclopentane 
                 3.26 
                 3.26 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 8.07 
                 8.22 
                 7.48 
               
               
                 Cyclohexane 
                 2.60 
                 2.60 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 5.60 
                 5.51 
                 5.96 
               
               
                 6O 
                 0.06 
                 0.06 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.18 
                 0.19 
                 0.14 
               
               
                 C7+ 
                 14.74 
                 14.74 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 19.37 
                 15.47 
                 33.80 
               
               
                 Vapor Phase 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Properties 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Mole Flow, 
                 — 
                 — 
                 3,581 
                 — 
                 0 
                 — 
                 — 
                 3,770 
                 — 
               
               
                 lbmole/hr 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Mass Flow, lb/hr 
                 — 
                 — 
                 254,370 
                 — 
                 0 
                 — 
                 — 
                 325,882 
                 — 
               
               
                 Actual Volumetric 
                 — 
                 — 
                 8,015 
                 — 
                 0 
                 — 
                 — 
                 7,884 
                 — 
               
               
                 Flow, ACFM 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Density, lb/ft3 
                 — 
                 — 
                 0.5289 
                 — 
                 0.5630 
                 — 
                 — 
                 0.6889 
                 — 
               
               
                 Viscosity, cP 
                 — 
                 — 
                 0.0078 
                 — 
                 0.0073 
                 — 
                 — 
                 0.0085 
                 — 
               
               
                 Heat Capacity, 
                 — 
                 — 
                 0.46 
                 — 
                 0.43 
                 — 
                 — 
                 0.49 
                 — 
               
               
                 Btu/lb-F. 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Thermal 
                 — 
                 — 
                 0.01 
                 — 
                 0.01 
                 — 
                 — 
                 0.01 
                 — 
               
               
                 Conductivity, 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Btu/hr-ft-F. 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Molecular Weight 
                 — 
                 — 
                 71.03 
                 — 
                 68.06 
                 — 
                 — 
                 86.43 
                 — 
               
               
                 Liquid Phase 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Properties 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Mole Flow, 
                 2,460 
                 2,460 
                 — 
                 3,581 
                 2,109 
                 1,441 
                 4,758 
                 — 
                 987 
               
               
                 lbmole/hr 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Mass Flow, lb/hr 
                 193,635 
                 193,635 
                 — 
                 254,370 
                 150,776 
                 103,021 
                 415,923 
                 — 
                 90,041 
               
               
                 Actual Volumetric 
                 596 
                 635 
                 — 
                 837 
                 499 
                 341 
                 1,390 
                 — 
                 298 
               
               
                 Flow, USGPM 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Std. Vol. Flow, 
                 19,853 
                 19,853 
                 — 
                 27,600 
                 16,384 
                 11,195 
                 40,666 
                 — 
                 8,669 
               
               
                 barrel/day 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Density, lb/ft3 
                 40.48 
                 38.03 
                 — 
                 37.91 
                 37.69 
                 37.69 
                 37.32 
                 — 
                 37.64 
               
               
                 Viscosity, cP 
                 0.2580 
                 0.1861 
                 — 
                 0.1955 
                 0.1898 
                 0.1898 
                 0.1601 
                 — 
                 0.1622 
               
               
                 Heat Capacity, 
                 0.5375 
                 0.5852 
                 — 
                 0.5647 
                 0.5675 
                 0.5675 
                 0.6150 
                 — 
                 0.6180 
               
               
                 Btu/lb-F. 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Thermal 
                 0.0615 
                 0.0554 
                 — 
                 0.0577 
                 0.0571 
                 0.0571 
                 0.0522 
                 — 
                 0.0523 
               
               
                 Conductivity, 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Btu/hr-ft-F. 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Molecular Weight 
                 78.72 
                 78.72 
                 — 
                 71.03 
                 71.51 
                 71.51 
                 87.42 
                 — 
                 91.19 
               
               
                 Blend Properties 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Viscosity: cSt 
                 0.40 
                 0.31 
                 — 
                 0.32 
                 0.31 
                 0.31 
                 0.27 
                 — 
                 0.27 
               
               
                 Std Density: kg/m3 
                 668 
                 668 
                 — 
                 631 
                 631 
                 631 
                 701 
                 — 
                 712 
               
               
                 RVP @ 100° F.: 
                 90 
                 90 
                 — 
                 133 
                 133 
                 133 
                 38 
                 — 
                 31 
               
               
                 kPa (absolute) 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 JPG RVP 
                   
                   
                   
                   
                   
                 19 
                   
                   
                   
               
               
                 ESTIMATE PSIA 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 TVP @ 100° F.: kPa 
                 97 
                 97 
                 — 
                 140 
                 140 
                 140 
                 38 
                 — 
                 31 
               
               
                 (absolute) 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Olefins: vol % 
                 0.50 
                 0.50 
                 — 
                 0.17 
                 0.17 
                 0.17 
                 0.49 
                 — 
                 0.93 
               
               
                 Benzene: vol % 
                 1.13 
                 1.13 
                 — 
                 0.00 
                 0.00 
                 0.00 
                 2.99 
                 — 
                 2.58 
               
               
                 BTEX: vol % 
                 2.08 
                 2.08 
                 — 
                 0.00 
                 0.00 
                 0.00 
                 4.12 
                 — 
                 4.76 
               
               
                 H2S: PPMws 
                 0.0 
                 0.0 
                 — 
                 0.0 
                 0.0 
                 0.0 
                 0.0 
                 — 
                 0.0 
               
               
                 C1-C3 Mercaptans: 
                 3 
                 3 
                 — 
                 3  
                 3 
                 3 
                 6 
                 — 
                 4 
               
               
                 PPMws 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Total Sulfur: 
                 10 
                 10 
                 — 
                 4 
                 4 
                 4 
                 22 
                 — 
                 17 
               
               
                 PPMws 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 2.b 
               
             
             
               
                   
               
               
                 Properties of Stream 10-34 
               
             
          
           
               
                   
                   
                   
                   
                   
                   
                   
                   
                 33 
                 34 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 CWS to 
                 CWR from 
               
               
                 Stream Number  
                 10 
                 11 
                 20 
                 21 
                 22 
                 31 
                 32 
                 Light 
                 Light 
               
               
                   
                 Cool Tower 
                 Light Naphtha  
                 MPS to 
                 Exhaust 
                 Conden- 
                 CWS to 
                 CWR from 
                 Naphtha 
                 Naphtha 
               
               
                 Stream Description 
                 Bottoms 
                 to Storage 
                 Reboiler 
                 Steam 
                 sate 
                 Condenser 
                 Condenser 
                 Cooler 
                 Cooler 
               
               
                   
               
             
          
           
               
                 Overall Properties 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Pressure, psig 
                 40 
                 40 
                 150 
                 10 
                 10 
                 50 
                 50 
                 50 
                 50 
               
               
                 Temperature, ° F. 
                 116 
                 100 
                 450 
                 239 
                 239 
                 90 
                 95 
                 90 
                 105 
               
               
                 Std. Vol Flow (V), 
                 — 
                 — 
                 24.5 
                 3.4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 MMSCFD 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Std. Vol Flow (L), 
                 8,721 
                 8,721 
                 — 
                 — 
                 0 
                 0 
                 0 
                 0 
                 0 
               
               
                 barrel/day 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Mass Flow, lb/hr 
                 90,027 
                 90,027 
                 48,609 
                 6,669 
                 41,940 
                 146,345 
                 146,345 
                 2,903,938 
                 2,903,938 
               
               
                 Mole Flow, 
                 987 
                 987 
                 2,698 
                 370 
                 2,328 
                 8,123 
                 8,123 
                 161,195 
                 161,195 
               
               
                 lbmole/hr 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Vapor Weight 
                 0.00 
                 0.00 
                 1.00 
                 1.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 Fraction 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Vapor Mole 
                 0.00 
                 0.00 
                 1.00 
                 1.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 Fraction 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Enthalpy Flow, 
                 −74.4 
                 −75.1 
                 −272.3 
                 −37.9 
                 −278.4 
                 −993.5 
                 −992.8 
                 −19713.8 
                 −19670.4 
               
               
                 Composition liq. 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 vol % 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 H2O 
                 0.00 
                 0.00 
                 100.00 
                 100.00 
                 100.00 
                 100.00 
                 100.00 
                 100.00 
                 100.00 
               
               
                 N-Butane 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 4O 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 N-Pentane 
                 2.30 
                 2.30 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 Isopentane 
                 0.16 
                 0.16 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 Cyclopentane 
                 1.33 
                 1.33 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 5O 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 Hexane 
                 21.81 
                 21.81 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 Benzene 
                 2.58 
                 2.58 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 22 Methylbutane 
                 0.75 
                 0.75 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 23 Methylbutane 
                 2.04 
                 2.04 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 2 Methylpentane 
                 14.23 
                 14.23 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 3 Methylpentane 
                 7.41 
                 7.41 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 Methylcyclopentane 
                 7.48 
                 7.48 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 Cyclohexane 
                 5.96 
                 5.96 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 6O 
                 0.14 
                 0.14 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 C7+ 
                 33.81 
                 33.81 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 Vapor Phase 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Properties 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Mole Flow, 
                 — 
                 — 
                 2,698 
                 370 
                 0 
                 — 
                 — 
                 — 
                 — 
               
               
                 lbmole/hr 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Mass Flow, lb/hr 
                 — 
                 — 
                 48,609 
                 6,669 
                 0 
                 — 
                 — 
                 — 
                 — 
               
               
                 Actual Volumetric 
                 — 
                 — 
                 2,538 
                 1,833 
                 0 
                 — 
                 — 
                 — 
                 — 
               
               
                 Flow, ACFM 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Density, lb/ft3 
                 — 
                 — 
                 0.3192 
                 0.0606 
                 0.0606 
                 — 
                 — 
                 — 
                 — 
               
               
                 Viscosity, cP 
                 — 
                 — 
                 0.0172 
                 0.0126 
                 0.0126 
                 — 
                 — 
                 — 
                 — 
               
               
                 Heat Capacity, 
                 — 
                 — 
                 0.56 
                 0.50 
                 0.50 
                 — 
                 — 
                 — 
                 — 
               
               
                 Btu/lb-F. 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Thermal 
                 — 
                 — 
                 0.02 
                 0.01 
                 0.01 
                 — 
                 — 
                 — 
                 — 
               
               
                 Conductivity, 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Btu/hr-ft-F. 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Molecular Weight 
                 — 
                 — 
                 18.02 
                 18.02 
                 18.02 
                 — 
                 — 
                 — 
                 — 
               
               
                 Liquid Phase 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Properties 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Mole Flow, 
                 987 
                 987 
                 — 
                 — 
                 2,328 
                 8,123 
                 8,123 
                 161,195 
                 161,195 
               
               
                 lbmole/hr 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Mass Flow, lb/hr 
                 90,027 
                 90,027 
                 — 
                 — 
                 41,940 
                 146,345 
                 146,345 
                 2,903,938 
                 2,903,938 
               
               
                 Actual Volumetric 
                 263 
                 260 
                 — 
                 — 
                 89 
                 294 
                 294 
                 5,829 
                 5,847 
               
               
                 Flow, USGPM 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Std. Vol. Flow, 
                 8,667 
                 8,667 
                 — 
                 — 
                 2,875 
                 10,031 
                 10,031 
                 199,051 
                 199,051 
               
               
                 barrel/day 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Density, lb/ft3 
                 42.60 
                 43.12 
                 — 
                 — 
                 59.08 
                 62.11 
                 62.05 
                 62.11 
                 61.93 
               
               
                 Viscosity, cP 
                 0.3199 
                 0.3501 
                 — 
                 — 
                 0.2401 
                 0.7606 
                 0.7185 
                 0.7606 
                 0.6446 
               
               
                 HeatCapacity, 
                 0.5194 
                 0.5090 
                 — 
                 — 
                 1.0122 
                 0.9980 
                 0.990 
                 0.9980 
                 0.9981 
               
               
                 Btu/lb-F. 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Thermal 
                 0.0648 
                 0.0662 
                 — 
                 — 
                 0.3962 
                 0.3590 
                 0.3612 
                 0.3590 
                 0.3653 
               
               
                 Conductivity 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Btu/hr-ft-F. 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Molecular Weight 
                 91.20 
                 91.20 
                 — 
                 — 
                 18.02 
                 18.02 
                 18.02 
                 18.02 
                 18.02 
               
               
                 Blend Properties 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Viscosity: cSt 
                 0.47 
                 0.51 
                 — 
                 — 
                 0.25 
                 0.76 
                 0.72 
                 0.76 
                 0.65 
               
               
                 Std Density: kg/m3 
                 712 
                 712 
                 — 
                 — 
                 1,000 
                 1,000 
                 1,000 
                 1,000 
                 1,000 
               
               
                 RVP @ 100° F.: 
                 31 
                 31 
                 — 
                 — 
                 7 
                 7 
                 7 
                 7 
                 7 
               
               
                 kPa (absolute) 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 JPG RVP 
                   
                 4.;5 
                   
                   
                   
                   
                   
                   
                   
               
               
                 ESTIMATE PSIA 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 TVP @ 100° F.: kPa 
                 31 
                 31 
                 — 
                 — 
                 7 
                 7 
                 7 
                 7 
                 7 
               
               
                 (absolute) 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Olefins: vol % 
                 0.93 
                 0.93 
                 — 
                 — 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 Benzene: vol % 
                 2.58 
                 2.58 
                 — 
                 — 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 BTEX: vol % 
                 4.76 
                 4.76 
                 — 
                 — 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
                 0.00 
               
               
                 H2S: PPMws 
                 0.0 
                 0.0 
                 — 
                 — 
                 0.0 
                 0.0 
                 0.0 
                 0.0 
                 0.0 
               
               
                 C1-C3 Mercaptans: 
                 4 
                 4 
                 — 
                 — 
                 0 
                 0 
                 0 
                 0 
                 0 
               
               
                 PPMws 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 Total Sulfur:  
                 17 
                 17 
                 — 
                 — 
                 0 
                 0 
                 0 
                 0 
                 0 
               
               
                 PPMws 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                   
               
             
          
         
       
     
       Example 3 
     Study to Determine the Effect of Mixed Pentanes on the Octane Value of a Refined Gasoline Stream 
       [0039]    Unleaded regular and premium gasoline blends satisfying the performance characteristics of ASTM D4814-01a were blended with varying amounts of a mixed pentane stream containing 55% n-pentane and 45% iso-pentane (hereinafter referred to as “mC 5 ”), a 55:45 mixture of the butane and mC 5 , a 80:20 mixture of the butane and mC 5 , and the resulting blends measured for RVP and octane. The same blends were subsequently mixed with 10% ethanol and their RVP and octane values measured a second time. RVP and octane values of the starting gasoline and resulting blends are reported below in Tables 3.a-3.f. 
         [0040]    All RVP values reported in the following examples were measured according to ASTM D 5191. Octane is reported as (R+M)/2, where R equals the research octane number calculated according to ASTM D 2699, and M equals the motor octane number calculated according to ASTM D 2700. Butane used in all blends as n-butane. 
         [0000]    
       
         
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 3.a 
               
               
                   
               
               
                   
                 CBOB 
                 CBOB + EtOH 
                 PBOB 
                 PBOB + EtOH 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 RVP 
                 5.82 
                 7.25 
                 5.28 
                 6.54 
               
               
                 +4.5% mC 5   
                 6.64 
                 — 
                 6.05 
                 — 
               
               
                 +12% mC 5   
                 7.24 
                 8.7 
                 7.24 
                 8.37 
               
               
                 +15% mC 5   
                 7.82 
                 — 
                 7.31 
                 — 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 3.b 
               
               
                   
               
               
                   
                 CBOB 
                 CBOB + EtOH 
                 PBOB 
                 PBOB + EtOH 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 RVP 
                 5.82 
                 7.25 
                 5.28 
                 6.54 
               
               
                 +3% 55/45 
                 6.92 
                 7.99 
                 6.48 
                 7.75 
               
               
                 +8% 55/45 
                 8.37 
                 — 
                 8.48 
                 — 
               
               
                 +11% 55/45 
                 9.94 
                 10.83 
                 9.36 
                 10.21 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 3.c 
               
               
                   
               
               
                   
                 CBOB 
                 CBOB + EtOH 
                 PBOB 
                 PBOB + EtOH 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 RVP 
                 5.82 
                 7.25 
                 5.28 
                 6.54 
               
               
                 +2% 80/20 
                 6.61 
                 — 
                 6.44 
                 — 
               
               
                 +6% 80/20 
                 8.43 
                 9.7 
                 8.48 
                 9.07 
               
               
                 +9% 80/20 
                 9.91 
                 — 
                 9.47 
                 — 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
               
               
               
               
             
           
               
                 TABLE 3.d 
               
               
                   
               
               
                   
                 CBOB 
                 CBOB + EtOH 
                 PBOB 
                 PBOB + EtOH 
               
               
                   
               
             
             
               
                 Octane 
                 83.2 
                 87.0 
                 91.2 
                 93.1 
               
               
                 +4.5% mC 5   
                 83.0 
                 — 
                 91.0 
                 — 
               
               
                 +12% mC 5   
                 83.0 
                 86.6 
                 91.0 
                 93.2 
               
               
                 +15% mC 5   
                 83.0 
                 — 
                 91.0 
                 — 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
               
               
               
               
             
           
               
                 TABLE 3.e 
               
               
                   
               
               
                   
                 CBOB 
                 CBOB + EtOH  
                 PBOB 
                 PBOB + EtOH 
               
               
                   
               
             
             
               
                 Octane 
                 83.2 
                 87.0 
                 91.2 
                 93.1 
               
               
                 +3% 55/45 
                 83.6 
                 87.2 
                 91.5 
                 93.3 
               
               
                 +8% 55/45 
                 83.6 
                 — 
                 91.2 
                 — 
               
               
                 +11% 55/45 
                 83.5 
                 87.5 
                 91.1 
                 93.5 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
               
               
               
               
             
           
               
                 TABLE 3.f 
               
               
                   
               
               
                   
                 CBOB 
                 CBOB + EtOH 
                 PBOB 
                 PBOB + EtOH 
               
               
                   
               
             
             
               
                 Octane 
                 83.2 
                 87.0 
                 91.2 
                 93.1 
               
               
                 +2% 80/20 
                 83.4 
                 — 
                 91.2 
                 — 
               
               
                 +6% 80/20 
                 83.5 
                 87.5 
                 91.0 
                 93.6 
               
               
                 +9% 80/20 
                 83.5 
                 — 
                 90.8 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 3.g 
               
               
                   
               
               
                   
                 CBOB 
                 CBOB + EtOH 
                 PBOB 
                 PBOB + EtOH 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 RVP 
                 11.12 
                 12.89 
                 11.2 
                 11.98 
               
               
                 +4% mC 5   
                 11.4 
                 12.4 
                 11.24 
                 12.1 
               
               
                 +7% mC 5   
                 11.37 
                 12.63 
                 11.5 
                 12.2 
               
               
                 +12% mC 5   
                 11.66 
                 12.83 
                 11.56 
                 12.49 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 3.h 
               
               
                   
               
               
                   
                 CBOB 
                 CBOB + EtOH 
                 PBOB 
                 PBOB + EtOH 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 RVP 
                 11.12 
                 12.89 
                 11.2 
                 11.98 
               
               
                 +6% 55/45 
                 12.3 
                 13.87 
                 12.46 
                 13.16 
               
               
                 +8% 55/45 
                 13.05 
                 14.21 
                 13.47 
                 14.14 
               
               
                 +9% 55/45 
                 13.34 
                 14.68 
                 13.71 
                 14.27 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 3.i 
               
               
                   
               
               
                   
                 CBOB 
                 CBOB + EtOH 
                 PBOB 
                 PBOB + EtOH 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 RVP 
                 11.12 
                 12.89 
                 11.2 
                 11.98 
               
               
                 +9% 80/20 
                 14.17 
                 15.16 
                 13.94 
                 13.84 
               
               
                 +12% 80/20 
                 15.32 
                 15.75 
                 14.62 
                 14.24 
               
               
                 +13% 80/20 
                 15.58 
                 16.82 
                 14.89 
                 15.59 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 3.j 
               
               
                   
               
               
                   
                 CBOB 
                 CBOB + EtOH 
                 PBOB 
                 PBOB + EtOH 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Octane 
                 84.1 
                 87.4 
                 92.3 
                 94.4 
               
               
                 +4% mC 5   
                 87.9 
                 87.6 
                 92.4 
                 94.5 
               
               
                 +7% mC 5   
                 87.8 
                 87.3 
                 92.4 
                 94.4 
               
               
                 +12% mC 5   
                 87.5 
                 87.1 
                 92.2 
                 93.9 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 3.k 
               
               
                   
               
               
                   
                 CBOB 
                 CBOB + EtOH 
                 PBOB 
                 PBOB + EtOH 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Octane 
                 84.1 
                 87.4 
                 92.3 
                 94.4 
               
               
                 +6% 55/45 
                 84 
                 87.6 
                 92.5 
                 94.5 
               
               
                 +8% 55/45 
                 84.1 
                 87.5 
                 92.3 
                 94.1 
               
               
                 +9% 55/45 
                 84.2 
                 87.5 
                 92.2 
                 94.1 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 3.l 
               
               
                   
               
               
                   
                 CBOB 
                 CBOB + EtOH 
                 PBOB 
                 PBOB + EtOH 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Octane 
                 84.1 
                 87.4 
                 92.3 
                 94.4 
               
               
                 +9% 80/20 
                 84.3 
                 87.6 
                 92.4 
                 94.4 
               
               
                 +12% 80/20 
                 84.2 
                 87.6 
                 92.4 
                 94.3 
               
               
                 +13% 80/20 
                 84.3 
                 87.6 
                 92.5 
                 94.1 
               
               
                   
               
             
          
         
       
     
         [0041]    Three notable findings emerge from the foregoing tables. The first emerges from Table 3.d, wherein it is seen that isopentane stabilizes the impact of n-pentane on the resulting blend, across the entire range of quantities tested. In site of a neat octane value of approximately 65 for n-pentane, the n-pentane added to the blend had very little impact on the octane of the resulting blend due to the presence of isopentane. 
         [0042]    The second finding relates to the impact of the mixed hydrocarbons (C 4  and C 5 ) on octane as the amount of pentanes increases, when added to a hydrocarbon stream that is eventually mixed with ethanol. This can be seen most clearly from the data in Tables 3.e and 3.f. As a general rule, increasing the quantity of mixed hydrocarbons (C 4  and C 5 ) either decreased the final octane value slightly or had no effect on the final octane value of the mixture. However, when ethanol was added to the blend a reversal to the trend was observed, with the ethanol blended octane value increasing with the additional mixed hydrocarbons. Indeed, synergy is observed at various blending rates, and is observed sooner (from a pentane standpoint) when the pentane is mixed with larger proportions of butane. 
         [0043]    The third finding relates to the consistency of the impact on octane as the ratio of butane and pentane components is varied. In fact, varying the ratio of butane to mixed pentanes had very little impact on the octane value of the resulting blend, demonstrating that RVP can be used as the controlling variable when a range of butane/pentane batches is added to the gasoline. 
         [0044]    Throughout this application, various publications are referenced. The disclosures of these publications are hereby incorporated by reference in order to more fully describe the state of the art to which this invention pertains. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.