Grace Davison s GENESIS Catalyst Systems Provide Refiners the Flexibility to Capture Economic Opportunities

Transcription

1 Grace Davison s GENESIS Systems Provide Refiners the Flexibility to Capture Economic Opportunities Rosann K. Schiller Product Manager FCC Grace Davison Refining Technologies Columbia, MD USA In these challenging times, refiners more than ever need flexibility. Demand for gasoline and diesel is down due to the recession. Product supply is volatile as refineries slow down rates and inventories rise with weak consumption; other refiners are extending turnarounds or in extreme cases, shutting down. Historically, the relative value of diesel to gasoline would fluctuate with the seasons in a fairly consistent band. However, as ultra-low sulfur fuels become standard, the price differential between diesel fuel and gasoline has become extremely volatile [Figure 1]. The refiners that are most successful are those that can react quickly to the changing supply/demand dynamics. 4 ISSUE No. 107 / 2010

2 Grace Davison delivers the flexibility most refiners need with the GENESIS catalyst system. GENESIS catalysts provide a means to maximize yield potential through the optimization of discrete cracking catalyst functionality 1. The GENESIS catalyst system has gained rapid market acceptance since it was launched by Grace Davison [Figure 2]. GEN- ESIS catalyst systems offer refiners formulation flexibility and the ability to realize the desired yield shifts quickly in order to capture dynamic economic opportunities. GENESIS catalyst is one of Grace Davison s most successful catalysts, with 20% of the world s FCC capacity having utilized the technology [Figure 3]. It is well known that the key to optimal FCC catalyst performance is the right balance between zeolite and matrix both in selectivity and activity. One representation of this is Z/M surface area ratio. 2 GENESIS catalysts are a blend of two catalyst types in which the principal component is a MIDAS catalyst. This concept provides the option to optimize formulation Z/M for each individual application. In many catalyst development tests, the expectation of performance for catalyst blends is that the resultant yields can be estimated by the linear average of the yields from each individual catalyst. In performance testing of GENESIS catalyst systems, the resultant yields exceed those of the individual components [Figure 4]. A synergistic effect therefore exists such that GEN- ESIS catalysts demonstrate a superior coke to bottoms relationship than either component alone. Remarkably, this effect is Figure 1 US Historical Price Differential Between Diesel and Gasoline Diesel - Gasoline Differential, cpg Number of Refiners Source: Energy Information Administration -60 Jan 94 Jan 98 Jan 02 Jan 06 Jan 10 Figure 2 GENESIS Has Gained Market Acceptance Quickly Figure 3 Worldwide Application Worldwide FCC Capacity, BPD GENESIS All Other s Source: Oil & Gas Journal GRACE DAVISON CATAGRAM 5

3 Figure 4 Evidence of GENESIS Synergy in Performance Testing Conversion, wt.% Coke, wt.% GENESIS IMPACT MIDAS Theoretical Blend observed across a broad range of feeds: resid, and hydrotreated feedstocks 1. For new applications, Grace s experienced technical service engineers carefully formulate the GENESIS catalyst to achieve the stated goals of the refiner. Often, several scenarios (e.g. max gasoline or max LCO) are prepared and presented to illustrate the flexibility and the power of GENESIS catalyst to change product slate. As product supply/demand balance shifts, GEN- ESIS catalyst in the unit can be reformulated to maximize profitability and capture short term economic opportunities. To speed implementation, formulation adjustment often takes place in the fresh hopper, minimizing the delay often associated with a catalyst change out. Grace has had over 80 applications of GENESIS catalysts in over 50 refineries [Table I] worldwide where the average user has reformulated, sometimes more than once to achieve new objectives. Examples of these successful commercial applications are presented here. In each case, GENESIS catalyst was either introduced or the blend reformulated to achieve the new objectives. 6 ISSUE No. 107 / 2010

4 Current Worldwide Use Refiner 1 The synergy we observe in laboratory testing has easily translated to field operation. Figure 5 illustrates the performance advantage observed in commercial testing with GENESIS catalyst. The data presented here are three commercially deactivated Ecats taken from an FCC unit processing resid that has used IMPACT and MIDAS catalysts separately as well as in a GENESIS catalyst system. These Ecats were then tested in an ACE pilot plant over a single feed from the same unit. GENE- SIS catalyst has the advantage in coke-selective bottoms cracking. Refiner 2 A refiner processing hydrotreated feed switched from a state-ofthe-art Grace Davison catalyst for hydrotreated feeds to a GEN- ESIS system. Figure 6 demonstrates the performance advantages of GENESIS catalyst relative to the hydrotreating benchmark technology. In ACE testing of unit Ecats, GENESIS catalyst results in an improved coke-to-bottoms relationship, ultimately providing operating flexibility for this refiner to optimize hydrotreating and FCC operations. This same refiner has also reformulated their GENESIS catalyst to take advantage of shifting economics between gasoline and LCO, by increasing the MIDAS catalyst portion of the blend. To accelerate turnover to the new formulation, Grace shipped MIDAS catalyst to adjust the formulation in the fresh hopper, eliminating any delay associated with excess fresh catalyst inventory. The Table I GENESIS Users Unit Region Feed Type Ni + V, ppm Refiner 1 Refiner 2 Refiner 3 Refiner 4 Refiner 5 Refiner 6 Refiner 7 Refiner 8 Refiner 9 Refiner 10 Refiner 11 Refiner 12 Refiner 13 Refiner 14 Refiner 15 Refiner 16 Refiner 17 Refiner 18 Refiner 19 Refiner 20 Refiner 21 Refiner 22 Refiner 23 Refiner 24 Refiner 25 Refiner 26 Refiner 27 Refiner 28 Refiner 29 Refiner 30 Refiner 31 Refiner 32 Refiner 33 Refiner 34 Refiner 35 Refiner 36 Refiner 37 Refiner 38 Refiner 39 Refiner 40 Refiner 41 Refiner 42 Refiner 43 Refiner 44 Refiner 45 Refiner 46 Refiner 47 Refiner 48 Refiner 49 Refiner 50 Refiner 51 Refiner GRACE DAVISON CATAGRAM 7

5 Figure 5 Evidence of GENESIS Synergy is Observed Commercially 9 8 IMPACT MIDAS GENESIS Bottoms, wt.% Coke, wt.% Figure 6 Commercial Data from Refiner 2 Observed Commercial Operations and Yields Shifts - GENESIS Delta Rg T, F Delta Rx T, F C/O Shift % Rel Delta Coke Shift % Rel G+D, vol.% Slurry, vol.% LPG, vol.% Dry Gas, wt.% new GENESIS catalyst formulation, when combined with adjusted operating conditions reduced ROT and endpoint adjustments enabled the refiner to maximize LCO production up to their downstream handling limits, without sacrificing octane or volume expansion. Total yield benefit was $0.50/bbl. Refiner 3 Another refiner changed from a competitive catalyst to a GENE- SIS catalyst. The yield benefits are summarized in Table II. GENESIS catalyst delivered enhanced bottoms conversion, gasoline and coke selectivity. In addition, GENESIS possesses more favorable fluidization characteristics than the competitive sample, and helped to overcome circulation instability [Figure 7]. GENESIS catalyst has also provided the flexibility to maximize profitability based on current supply/demand economics. Since introduction to the unit, Refiner 3 has reformulated GEN- 8 ISSUE No. 107 / 2010

6 ESIS catalyst twice; first to maximize LCO and again to return to a gasoline operation. In the max LCO operation, the percentage of MIDAS catalyst was increased in the blend to maximize bottoms cracking and reduce Z/M. The shifts achieved in the max LCO case are summarized in Table II. GENESIS 2 catalyst, formulated for max LCO, delivered an additional 3.5 lv.% yield for a net increase of 5 lv.% LCO and 2.2 lv.% reduction in slurry relative to the competitive base catalyst. When economics became favorable for gasoline, the refiner returned to the original formulation. Overall, these yield shifts were worth between $0.45 and $1.00/bbl, depending on the operating mode and the refining margins at the time. For both catalyst reformulations, the blend ratio of MIDAS catalyst and IMPACT catalyst was adjusted to achieve the desired yield shift. Grace was able to reduce turnover time by working with the refiner to readjust the formulation within the fresh catalyst hopper. Refiner 4 A major refiner desired additional bottoms conversion. A switch to GENESIS catalyst delivered increased conversion to gasoline and LPG without sacrificing coke selectivity. The yield shifts are shown in Table III. The new GENESIS catalyst achieved the goal of 2% more conversion at equivalent coke yields, increasing revenue by $0.44/bbl. Refiner 5 A refiner desired increased bottoms conversion and enhanced LCO production. The use of a GENESIS catalyst, along with an adjustment in operating con- Table II GENESIS Provided Refiner 3 the Flexibility to Shift Between Gasoline and LCO Modes Gasoline, lv.% LCO, lv.% Bottoms, lv.% Fluidization Factor (Umb/Umf) Competitive Base Base Base GENESIS Competitive GENESIS 1 (Max Gasoline) relative to base Figure 7 Fluidization Improved with GENESIS at Refiner 3 Oct Jan Apr Jul Oct Table III GENESIS Yield Shifts at Refiner 4 Feed I Regenerator Temperature, F Light Ends, lv.% Gasoline, lv.% LCO, lv.% Slurry, lv.% Conversion, lv.% Yield shifts with GENESIS GENESIS 2 (Max LCO) relative to base GRACE DAVISON CATAGRAM 9

7 ditions, delivered a 5% increase in LCO without a debit in coke selectivity. When economics returned to favor gasoline, similarly to the earlier example, the blend ratio was adjusted and severity increased to favor a gasoline operation. The new GENESIS catalyst formulation delivered operating flexibility and enhanced profitability by $0.55/bbl. Refiner 6 A refiner processing resid was seeking additional bottoms cracking without sacrificing coke selectivity or metals tolerance. GENESIS catalyst delivered an increase of +10 m 2 /g in Ecat matrix surface area, a 1.5 lv.% reduction in bottoms yield, and +2.0 lv.% conversion compared to a base IMPACT catalyst formulation. Even though Ecat metals levels increased by almost 10% due to a feed change, GENESIS maintained coke, H 2, and gas selectivity. [Figure 8] Refiner 7 This refiner adopted GENESIS catalyst to replace a competitive resid technology. GENESIS delivered 1.5 lv.% increase in conversion to gasoline and LPG olefins, at the expense of slurry, which was worth $0.43/bbl. Not only has GENESIS catalyst minimized slurry yield, it did so without the expected coke and gas penalty often observed with competitive high matrix catalysts. GENESIS catalyst GENESIS catalyst systems have been applied in over 50 refiners worldwide with 80 discrete applications. allowed this refiner to maximize feed carbon content up to the coke burn limit. Refiner 8 The success of GENESIS catalyst has spurred some competi- Figure 8 Ecat Selectivities are Maintained with GENESIS Despite Higher Ecat Metals Coke Factor Gas Factor H 2 Yield SCFB IMPACT GENESIS Ecat Ni Equivalents, ppm 10 ISSUE No. 107 / 2010

8 tive imitations. One refiner has trialed both a competitive offering as well as a GENESIS catalyst system. The yields are summarized in Table IV. At equivalent activity and coke yield, GENESIS catalyst delivered enhanced bottoms cracking. Hydrogen selectivity was also improved at equivalent Ecat metals. Emulating the performance of GENESIS catalyst is not as simple as merely blending a high zeolite activity catalyst with a high matrix catalyst. The combination of MIDAS catalyst matrix technology with Grace s proprietary zeolite technology results in a true synergy unmatched by the competition. Refiner 9 Lastly, we hear a lot about how additives are the easy way to achieve a desired yield shift quickly. Additives can generally be delivered and injected into the inventory quickly, provided the appropriate injection equipment is in place, the loader lease agreement allows use of an additive, the additive is available in inventory, and management approves the use of the product. For a very short term opportunity, once the hurdles are overcome, an additive usually works well. However, additives are not custom formulated products. Therefore, if a refiner is looking for a long term application, and the additive is not delivering, the desired yield shifts will not be achieved. A refiner desired additional bottoms cracking and trialed both an additive solution and a GENESIS catalyst system. The additive solution did provide incremental bottoms cracking, but because it was not designed and formulated for this Table IV GENESIS Provided Refiner 8 Performance Advantages Relative to the Competition Constant Coke Comparison Conversion, wt.% H 2 /CH 4 Ratio Gasoline, wt.% LCO/Bottoms, w/w Total Ecat Metals, ppm H 2 /CH 4 Ratio Gasoline, wt.% LCO, wt.% Bottoms, wt.% Coke, wt.% GENESIS Additive approach relative to base Competitive Table V GENESIS Delivered Refiner 9 More Selective Bottoms Cracking than an Additive Approach operation, the consequence was a substantial coke debit and a loss in gasoline yield. The GEN- ESIS catalyst formulation, with each component designed and manufactured specifically for the application, delivered the targeted bottoms conversion, while improving coke and gas selectivities relative to the base operation [Table V]. GENESIS relative to base GRACE DAVISON CATAGRAM 11

9 Conclusions GENESIS catalyst offers customers the ultimate in formulation flexibility and the option to realize those changes quickly. A decision to reformulate within a GENESIS catalyst system typically happens 80% quicker than with a traditional catalyst because simply changing the blend ratio presents a lower risk option than a new catalyst or even a new additive. GENESIS catalyst systems have been applied in over 50 refiners worldwide with 80 discrete applications. Z/M ratio can be optimized to match the specific unit feedstock and operating constraints. In addition to optimizing the blend ratio, the activity levels of the individual components are carefully selected to match the operating mode and feed types. This formulation flexibility can deliver a significant selectivity change, allowing a refiner to accommodate a seasonal operation, manage a swing feedstock or even a hydrotreater outage, and most importantly, GENESIS catalyst systems allow refiners to capture short term economic opportunities. References 1. Schiller, R., et al, The GENESIS System, Catalagram publication No. 102, Fall Mott, R.W., Wear, C. FCC Design for Optimal Performance, NPRA 1988, AM ISSUE No. 107 / 2010