UPGRADING SIMPLIFIED PROCESS FOR HEAVY OILS FLUIDIZATION DEDICATED TO THE HEAVY OILS TRANSPORTATION AND GREENHOUSE GAS REDUCTION

Abstract

An economic and sustainable process is described herein for zeroing the addition of diluent required in heavy oils transportation by pipelines and by rails. The process reduces both heavy oils characteristics such as: (a) viscosity, (b) density, (c) acidic compounds (TAN), (d) sulfur and (e) olefins generated during the thermal treatment in order to meet stablished criteria for transportation. To prevent premature catalyst deactivation and precipitation, the solids materials in the crude heavy oil are removed first through a physical separation unit, and constitutes a fraction called solid fraction (≤30%), while the solids free fraction or de-solidified fraction (≥70%) of the heavy oil undergoes a thermo-catalytic treatment in a second unit under hydrogen pressure. During this step, both heavy oils properties listed above are reduced. Once produced, the olefins are then saturated by the hydrogen (or additive) present during the reaction yielding a stable treated heavy oil.

Claims

1. A process for heavy oil upgrading comprising: removing a solid fraction (SF) of the heavy oil using a breathing semi-fluidized bed, resulting in a de-solidified fraction (DSF); wherein the SF represents less than 30 wt % of the heavy oil; washing or desulfurizing the SF with a saline solution to remove heteroatoms, resulting in a desulphurized solid fraction (DSSF); subjecting the DSF under thermal treatment in presence of a catalyst and hydrogen so as to produce a fluidized desolidified fraction (FDSF); and remixing the DSSF and the FDSF to generate a Synthetic Crude Oil (SCO).

2. The process according to claim 1, wherein the heavy oil contains diluent from production field at trace level or at a given percentage.

3. The process of claim 1 wherein the DSF represents more than 70 wt % of the heavy oil.

4. The process according to claim 1, wherein the FDSF is further used as feedstock in a local refinery.

5. The process according to claim 1, wherein said removing a solid fraction (SF) of the heavy oil is carried below 350° C. and 1000 Psig.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In the appended drawings:

[0042] FIG. 1 is a schematic view of a heavy oil partial upgrading process according to an illustrative embodiment.

DETAILED DESCRIPTION

[0043] In the following description, similar features in the drawings have been given similar reference numerals, and in order not to weigh down the FIGURES, some elements are not referred to in some FIGURES if they were already identified in a precedent FIGURE.

[0044] The use of the word “a” or “an” when used in conjunction with the term “comprising” in the claims and/or the specification may mean “one”, but it is also consistent with the meaning of “one or more”, “at least one”, and “one or more than one”. Similarly, the word “another” may mean at least a second or more.

[0045] As used in this specification and claim(s), the words “comprising” (and any form of comprising, such as “comprise” and “comprises”), “having” (and any form of having, such as “have” and “has”), “including” (and any form of including, such as “include” and “includes”) or “containing” (and any form of containing, such as “contain” and “contains”), are inclusive or open-ended and do not exclude additional, unrecited elements.

[0046] With reference to FIG. 1, an apparatus dedicated to heavy oils upgrading according to an illustrative embodiment includes a heavy oils or dilbit tank 201, a physical separation unit 203, the solids fraction decontamination or desulfurization unit 207, the key main unit for catalytic fluidization 206, and a mixing or receiving tank 210 to yield Synthetic Crude Oil.

[0047] The preheated heavy oil or dilbit from the tank 201 enters the separation unit 203, through conduit 202, wherein the separation is carried below 350° C. and 1000 Psig, without limitations, via a breathing semi-fluidized bed or a fixed bed of inert materials or via any other means of separation.

[0048] As a result, two fractions are generated: a solid fraction SF representing ≤30 wt %, and a de-solidified fraction DSF, accounting for ≥70 wt %. It is to be noted that sometimes, but rarely, the percentage of SF is greater than 30 wt % and the percentage of DSF is lower than 70 wt %.

[0049] The presence of solids materials during hydrocarbons processing is a real danger in that they are responsible of fines deposition and can lead to catalyst bed plugging and catalysts deactivation.

[0050] The removal of solids materials (metals, fines particles, asphaltenes, heteroatoms etc.) prior to heavy oils thermo-catalytic treatment, avoids such problems to the catalysts inserted in the downstream units.

[0051] The de-solidified fraction is then routed via conduit or line 204, to the key main unit 206 for fluidization reaction above 350° C. & 400 Psig through a catalytic semi-fluidized bed or a catalytic fixed bed, as well as any other catalytic bed using a catalyst material associated with a given additive, such as hydrogen.

[0052] The presence of the catalyst and hydrogen in the reaction medium play two roles: a) the catalytic treatment breaks down the macromolecules forming the de-solidified fraction DSF, to yield a fluidized de-solidified fraction FDSF (≥70% wt %, but not limited) with lower viscosity and density well below the values set as criteria for the transportation; b) elsewhere, said thermo-catalytic treatment in the presence of hydrogen improves at the same time others qualities of material and avoids the possible discounts.

[0053] In fact, when hydrogen is present in the thermo-catalytic medium, cracked molecules, particularly olefins are saturated and treated heavy oil become stable (stability index, P-Value≥1.5). The sulfur is eliminated in form of H.sub.2S, while acidic components often concentrated in the cut ranging from 232 to 427° C. (according to Merichem and Nalco Inc.), are eliminated or destroyed, which is beneficial for producers.

[0054] In another embodiment dedicated to local market, fluidized de-solidified fraction, FDSF, from line 208 is considered as refinery feedstock and solid fraction from line 205 is used in gasifier, co-regeneration, but not limited.

[0055] Thirdly, if needed, in order to satisfy new marine fuel standard of 0.5% S, the isolated solid fraction, SF from separation unit enters the decontamination unit 207, through conduit 205, whereby it undergoes (together or not with the produced H.sub.2S) a desulfurization step in contact with a saline solution such as caustic solution, but not limited, to yield a desulfurized solid fraction, noted DSSF (≤30 wt %, but not limited).

[0056] The desulfurized solid fraction, DSSF, free from sulfur, metals and fines particles exits through conduit 209 and is then combined with fluidized de-solidified fraction, FDSF, from conduit 208 to generate the so-called Synthetic Crude Oil (SCO), meeting required criteria and ready for transportation by pipeline or rails.

Example

[0057] A fluidization experiment was carried out according to the apparatus illustrated in FIG. 1. An Athabasca bitumen having the properties indicated in table #1 below was used as feedstock.

TABLE-US-00001 TABLE 1 Results from catalytic fluidization or upgrading at 420° C. and WHSV = 4/h under 2000 Psig SCO for overseas Upgraded Upgraded or products products Home/ inter- vs HO key Properties Feedstock Properties FDSF national properties units HO specs. refineries markets API gravity (°) 8.50 ≥19 32 19 (ok) @15.6° C. Viscosity (cP) 700015 ≤350 90 ≤150 (ok) @12° C. TAN (mg- 2.41 ≤1.0 0.5 0.63 (No) KOH/g) Sulfur (wt %) 4.60 ≤0.5 0.4 0.81 (No) reduction Olefins/ (g-Br.sub.2/ — ≤10 5 3.87 (ok) Bromine 100 g)* Nbre Stability (—) NA ≥1.5 3.0 2.5 (ok) P-Value Legend: (ok): Specification is satisfied; (No): Specification is not satisfied; (NA): Data is not available; *10 g-Br2/100 g is equivalent to: 1 wt % of olefins;

[0058] The Athabasca bitumen having a viscosity of 152015 cP and 700015 cP respectively at 15° C. and 12° C. was fluidized in the conditions indicated above (details are not shown herein). The properties of the different products, including FDSF and SCO are presented in table#1. The observation made based of these results is that the objectives fixed by the current process are met on dispute of minor variations due to measurements or operating conditions (e.g.: case of SCO) and which can be improved.

[0059] Although a process for heavy oils fluidization dedicated to the heavy oils transportation and greenhouse gas reduction has been described hereinabove by way of illustrated embodiments thereof, it can be modified. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that the scope of the claims should not be limited by the preferred embodiment, but should be given the broadest interpretation consistent with the description as a whole.