Processes for creating renewable energy

Abstract

A method of generating hydrogen from off-gas includes obtaining off-gas from a renewable diesel unit (RDU) and inputting the off-gas to a steam methane reformer (SMR). The hydrogen is generated via utilization of the SMR. In another aspect, a method of generating hydrogen from off-gas includes obtaining off-gas from the RDU, inputting the off-gas to a pre-reforming reactor to produce methane, and inputting the methane to the SMR. The hydrogen is generated from the methane. In another aspect, a method of providing hydrogen to an RDU includes obtaining off-gas from the RDU and converting the off-gas to hydrogen. The hydrogen is generated via the SMR, and subsequently providing the hydrogen to the RDU.

Description

Technical Field

[0001] (Cross - Reference to Related Applications) This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Application No. 63 / 327,114, filed on April 4, 2022, the entire disclosure of which is incorporated herein by reference.

Background Art

[0002] The use of biomass, such as vegetable oils and animal fats, as renewable resources for fuel production is highly desirable for many reasons, including energy security, greenhouse gas reduction, and agricultural economy. In this regard, the reconfiguration of operations from fossil fuel production to renewable fuel production is currently underway. For example, new plants can be built, and refining plants can be converted to process biomass into high - quality “drop - in” renewable fuels such as diesel, naphtha, and sustainable aviation fuel (SAF).

[0003] However, biomass feedstocks consume a relatively large amount of hydrogen during processing compared to conventional oil refining, and the catalytic reactions generate substantial exothermic heat releases that require quenching and / or product recirculation to control. This relatively more intensive processing, with the chemical characteristics of biomass feedstocks, also causes a much higher yield of low - value by - products, such as, for example, water, carbon monoxide, carbon dioxide, methane, ethane, propane, and / or butane. Therefore, there is a need to beneficially utilize such by - products.

Summary of the Invention

[0004] This disclosure provides a method for integrating technology into a novel process in which hydrogen is generated from these low-value by-products. For example, the by-products can be obtained from a renewable diesel unit (RDU) used in converting biomass into renewable fuel, and such off-gas can then be used to generate hydrogen for use in the manufacturing process. For example, the off-gas can be fed into a steam methane reformer (SMR) to generate hydrogen. Additionally, or alternatively, the off-gas can be fed into a pre-reforming reactor to generate methane, which can then be fed into an SMR to generate hydrogen. [Brief explanation of the drawing]

[0005] [Figure 1] This illustrates the overall process of converting renewable biomass into renewable fuel. [Modes for carrying out the invention]

[0006] The following numbered embodiments are intended, and the embodiments are not limiting. 1. A method for generating hydrogen from off-gas, the method comprising the steps of obtaining off-gas from a regenerative diesel unit (RDU) and introducing the off-gas into a steam methane reformer (SMR), wherein hydrogen is produced through the use of the SMR. 2. The method according to Clause 1, any other suitable Clause, or any combination of the suitable Clauses, wherein the hydrogen is renewable hydrogen. 3. The method of Clause 1, any other preferred Clause, or any combination of the preferred Clauses, wherein hydrogen is produced with lower levels of nitrogen oxide (NOx) emissions. 4. The method of Clause 3, any other suitable Clause, or any combination of the suitable Clauses, wherein the lower level of NOx emissions is less than 0.05 lb / MMBtu. 5. The method of Clause 3, any other preferred Clause, or any combination of preferred Clauses, wherein lower levels of NOx emissions are provided after selective catalytic reduction (SCR). 6. The method of Clause 3, any other suitable Clause, or any combination of the suitable Clauses, which reduces lower levels of NOx emissions by up to an additional 95%. 7. The method according to Clause 1, any other preferred Clause, or any combination of preferred Clauses, wherein the off-gas is selected from the group consisting of carbon monoxide, carbon dioxide, methane, ethane, propane, butane, hydrogen, and any combination thereof. 8. The method of Clause 1, any other suitable Clause, or any combination of the suitable Clauses, wherein the off-gas contains carbon monoxide. 9. The method of Clause 1, any other suitable Clause, or any combination of the suitable Clauses, wherein the off-gas includes carbon dioxide. 10. The method of off-gas containing methane, as described in Clause 1, any other suitable Clause, or any combination of the suitable Clauses. 11. The method according to Clause 1, any other suitable Clause, or any combination of the suitable Clauses, wherein the off-gas contains ethane. 12. The method of off-gas containing propane, any other suitable clause, or any combination of the suitable clauses. 13. The method by which the off-gas contains butane, as described in Clause 1, any other suitable Clause, or any combination of the suitable Clauses. 14. The method of SMR comprising a pressure swing adsorption (PSA) process, as described in Clause 1, any other preferred Clause, or any combination of the preferred Clauses. 15. The method of Clause 1, any other suitable Clause, or any combination of the suitable Clauses, wherein off-gas is introduced into the SMR via a compressor. 16. A method for generating hydrogen from an off-gas, wherein the method is The steps include obtaining off-gas from a recyclable diesel unit (RDU), The steps include: introducing off-gas into a pre-reforming reactor to produce methane, A method comprising the steps of introducing methane into a steam methane reformer (SMR), wherein hydrogen is produced from the methane. 17. The method according to Clause 16, any other suitable Clause, or any combination of the suitable Clauses, wherein hydrogen is subsequently introduced into the RDU. 18. The method according to Clause 16, any other suitable Clause, or any combination of suitable Clauses, wherein hydrogen is subsequently introduced into a second RDU. 19. The method by which hydrogen is renewable hydrogen, according to Clause 16, any other suitable Clause, or any combination of the suitable Clauses. 20. The method of Clause 16, any other preferred Clause, or any combination of the preferred Clauses, wherein hydrogen is produced with lower levels of nitrogen oxide (NOx) emissions. 21. The method by which NOx emissions are less than 0.05 lb / MMBtu, by clause 20, any other suitable clause, or any combination of the suitable clauses. 22. The method of clause 20, any other preferred clause, or any combination of preferred clauses, wherein lower levels of NOx emissions are provided after selective catalytic reduction (SCR). 23. A method by which lower levels of NOx emissions are reduced by up to an additional 95% by clause 20, any other suitable clause, or any combination of the suitable clauses. 24. The method according to Clause 16, any other preferred Clause, or any combination of preferred Clauses, wherein the off-gas is selected from the group consisting of carbon monoxide, carbon dioxide, methane, ethane, propane, butane, hydrogen, and any combination thereof. 25. The method of using Clause 16, any other suitable Clause, or any combination of the suitable Clauses, wherein the off-gas contains carbon monoxide. 26. The method by which the off-gas includes carbon dioxide, by clause 16, any other suitable clause, or any combination of the suitable clauses. 27. The method by which the off-gas contains methane, according to clause 16, any other suitable clause, or any combination of the suitable clauses. 28. The method of off-gas containing ethane, as described in Clause 16, any other suitable Clause, or any combination of the suitable Clauses. 29. The method by which the off-gas includes propane, as described in Clause 16, any other suitable Clause, or any combination of the suitable Clauses. 30. The method by which the off-gas is butane, including butane, as described in Clause 16, any other suitable Clause, or any combination of the suitable Clauses. 31. The method according to clause 16, any other suitable clause, or any combination of the suitable clauses, wherein the off-gas is introduced into the pre-reforming reactor via a compressor. 32. The method by which SMR is performed, comprising a pressure swing adsorption (PSA) process, as described in clause 16, any other preferred clause, or any combination of the preferred clauses. 33. A method by which the method is carried out in such a manner as not substantially using natural gas, by any other suitable provision, or any combination of the suitable provisions. 34. A method by which the method is carried out in such a manner that methane from natural gas is substantially not used, by any other suitable provision, or any combination of the suitable provisions. 35. A method for supplying hydrogen to a renewable diesel unit (RDU), the method comprising: obtaining off-gas from the RDU; converting the off-gas to hydrogen, wherein the hydrogen is produced via a steam methane reformer (SMR); and subsequently supplying the hydrogen to the RDU. 36. The method of Clause 35, any other suitable Clause, or any combination of the suitable Clauses, wherein the conversion of the off-gas to hydrogen includes the step of introducing the off-gas into a pre-reforming reactor to produce methane. 37. The method of clause 36, any other suitable clause, or any combination of the suitable clauses, wherein methane is introduced into an SMR and hydrogen is produced from the methane. 38. The hydrogen is renewable hydrogen, as described in Clause 35, any other suitable Clause, or any combination of the suitable Clauses. 39. The method of Clause 35, any other preferred Clause, or any combination of the preferred Clauses, wherein hydrogen is produced with lower levels of nitrogen oxide (NOx) emissions. 40. A lower level of NOx emissions is less than 0.05 lb / MMBtu, as described in Clause 39, any other preferred Clause, or any combination of the preferred Clauses. 41. The method of Clause 39, any other preferred Clause, or any combination of preferred Clauses, wherein lower levels of NOx emissions are provided after selective catalytic reduction (SCR). 42. The method by which lower levels of NOx emissions are reduced by up to an additional 95%, as described in Clause 39, any other suitable Clause, or any combination of the suitable Clauses. 43. The method according to Clause 35, any other preferred Clause, or any combination of preferred Clauses, wherein the off-gas is selected from the group consisting of carbon monoxide, carbon dioxide, methane, ethane, propane, butane, hydrogen, and any combination thereof. 44. The method of clause 35, any other suitable clause, or any combination of suitable clauses, wherein the off-gas contains carbon monoxide. 45. The method by which the off-gas includes carbon dioxide, as described in Clause 35, any other suitable Clause, or any combination of the suitable Clauses. 46. ​​The method of off-gas containing methane, as described in Clause 35, any other suitable Clause, or any combination of the suitable Clauses. 47. The method of the off-gas containing ethane, as described in Clause 35, any other suitable Clause, or any combination of the suitable Clauses. 48. The method by which the off-gas includes propane, as described in Clause 35, any other suitable Clause, or any combination of the suitable Clauses. 49. The method by which the off-gas is butane, as described in Clause 35, any other suitable Clause, or any combination of the suitable Clauses. 50. The method according to clause 35, any other suitable clause, or any combination of suitable clauses, wherein the SMR includes a pressure swing adsorption (PSA) process. 51. The method according to clause 35, any other suitable clause, or any combination of suitable clauses, wherein the off-gas is introduced into the SMR via a compressor.

[0007] In an exemplary embodiment, a method for generating hydrogen from off-gas is provided. The method includes obtaining off-gas from a renewable diesel unit (RDU) and introducing the off-gas into a steam methane reformer (SMR), and hydrogen is generated via utilization of the SMR.

[0008] In one embodiment, the hydrogen is renewable hydrogen. In one embodiment, the hydrogen is generated with a lower level of nitrogen oxide (NOx) emissions. In one embodiment, the lower level of NOx emissions is less than 0.05 lb / MMBtu. In one embodiment, the lower level of NOx emissions is provided after selective catalytic reduction (SCR). In one embodiment, the lower level of NOx emissions is additionally reduced by up to 95%.

[0009] In one embodiment, the off-gas is selected from the group consisting of carbon monoxide, carbon dioxide, methane, ethane, propane, butane, hydrogen, and any combination thereof. In one embodiment, the off-gas includes carbon monoxide. In one embodiment, the off-gas includes carbon dioxide. In one embodiment, the off-gas includes methane. In one embodiment, the off-gas includes ethane. In one embodiment, the off-gas includes propane. In one embodiment, the off-gas includes butane.

[0010] In one embodiment, the SMR includes a pressure swing adsorption (PSA) process. In one embodiment, the off-gas is introduced into the SMR via a compressor.

[0011] In an illustrative embodiment, a method for generating hydrogen from off-gas is provided. The method includes the steps of: obtaining off-gas from a renewable diesel unit (RDU); feeding the off-gas into a pre-reforming reactor to produce methane; and feeding the methane into a steam methane reformer (SMR) to which hydrogen is produced from the methane.

[0012] In one embodiment, hydrogen is subsequently introduced into an RDU. In another embodiment, hydrogen is subsequently introduced into a second RDU.

[0013] In one embodiment, the hydrogen is renewable hydrogen. In one embodiment, the hydrogen is produced with lower levels of nitrogen oxide (NOx) emissions. In one embodiment, the lower levels of NOx emissions are less than 0.05 lb / MMBtu. In one embodiment, the lower levels of NOx emissions are provided after selective catalytic reduction (SCR). In one embodiment, the lower levels of NOx emissions are reduced by up to an additional 95%.

[0014] In one embodiment, the off-gas is selected from the group consisting of carbon monoxide, carbon dioxide, methane, ethane, propane, butane, hydrogen, and any combination thereof. In one embodiment, the off-gas contains carbon monoxide. In one embodiment, the off-gas contains carbon dioxide. In one embodiment, the off-gas contains methane. In one embodiment, the off-gas contains ethane. In one embodiment, the off-gas contains propane. In one embodiment, the off-gas contains butane.

[0015] In one embodiment, the off-gas is introduced into the pre-reforming reactor via a compressor. In one embodiment, the SMR includes a pressure swing adsorption (PSA) process.

[0016] In one embodiment, the method is carried out in a manner that substantially avoids the use of natural gas. In another embodiment, the method is carried out in a manner that substantially avoids the use of methane from natural gas.

[0017] In an exemplary embodiment, a method for supplying hydrogen to a renewable diesel unit (RDU) is provided. The method includes the steps of: obtaining off-gas from the RDU; converting the off-gas to hydrogen, wherein the hydrogen is produced via a steam methane reformer (SMR); and subsequently supplying the hydrogen to the RDU.

[0018] In one embodiment, the conversion of off-gas to hydrogen includes the step of feeding the off-gas into a pre-reforming reactor to produce methane. In one embodiment, the methane is fed into the SMR, and hydrogen is produced from the methane.

[0019] In one embodiment, the hydrogen is renewable hydrogen. In one embodiment, the hydrogen is produced with lower levels of nitrogen oxide (NOx) emissions. In one embodiment, the lower levels of NOx emissions are less than 0.05 lb / MMBtu. In one embodiment, the lower levels of NOx emissions are provided after selective catalytic reduction (SCR). In one embodiment, the lower levels of NOx emissions are reduced by up to an additional 95%.

[0020] In one embodiment, the off-gas is selected from the group consisting of carbon monoxide, carbon dioxide, methane, ethane, propane, butane, hydrogen, and any combination thereof. In one embodiment, the off-gas contains carbon monoxide. In one embodiment, the off-gas contains carbon dioxide. In one embodiment, the off-gas contains methane. In one embodiment, the off-gas contains ethane. In one embodiment, the off-gas contains propane. In one embodiment, the off-gas contains butane.

[0021] In one embodiment, the SMR includes a pressure swing adsorption (PSA) process. In one embodiment, off-gas is introduced into the SMR via a compressor.

[0022] In one embodiment, CO2 generated in the SMR and water-gas shift reactor can be captured from the synthesis gas, thereby resulting in negative carbon dioxide emissions.

[0023] In one embodiment, CO2 can be captured from the SMR flue gas, resulting in negative carbon dioxide emissions.

[0024] In one embodiment, CO2 can be captured from the PSA purge gas, resulting in negative carbon dioxide emissions.

[0025] In one embodiment, CO2 is collected, compressed, and transported or sequestrated, either individually or collectively, for use as a chemical raw material.

[0026] In one embodiment, the SMR is provided with fuel from renewable hydrogen. [Examples]

[0027] Advantageously, the hydrogen produced from undesirable off-gases can subsequently be fed back into the RDU as part of the overall production process of renewable fuels such as renewable naphtha, renewable aviation fuel, and / or renewable diesel. Producing “environmentally friendly” renewable hydrogen in this way can desirablely reduce or even eliminate the need for natural gas, which is typically used for hydrogen production. Next, this favorably reduces the carbon dioxide emissions of the entire renewable diesel process, depending on the amount of off-gases produced. The method of this disclosure provides a novel mechanism for the efficient modification and utilization of standard SMR hydrogen plant technology. In addition, the method of this disclosure can produce lower levels of nitrogen oxide (NOx) emissions to meet ultra-low NOx emission standards and thus reduce the need for additional environmental control. This design is intended to ultimately reduce NOx by up to an additional 95%, for example, via a selective catalytic reduction (SCR) facility. For example, this could be part of a CO2 capture-ready design, since NOx emissions tend to increase when “inert” CO2 (inert to the combustion process) is removed from the purge gas.

[0028] The entire process of converting renewable biomass into renewable fuel is shown in Figure 1. This process utilizes biomass (e.g., oil from seed oils, reduced animal fat, etc.) as raw materials for the renewable fuel production process. Generally, raw materials may contain various toxic or contaminant substances for the catalyst system used in the RDU. Therefore, the raw materials are typically washed in a pretreatment unit (PTU) that hydrolyzes phospholipids and removes metals and other inorganic contaminants.

[0029] Next, the feedstock is fed into the RDU, where a hydrogen-rich catalytic hydrogenation process converts the feedstock into a renewable fuel. In one embodiment, the RDU may comprise a single reactor having multiple fixed catalyst beds. In the first bed of the reactor, the feedstock can be converted into a renewable fuel (e.g., diesel, aviation, and / or naphtha) through various reactions. The later bed of the reactor provides a catalyst designed for isomerization of the renewable product to improve the low-temperature fluidity properties of the renewable fuel. Importantly, the conversion reaction requires the consumption of hydrogen.

[0030] The ultimate result of this process is the conversion of biomass into renewable fuels (e.g., diesel, aviation, and naphtha). However, as previously explained, this process also produces low-value byproducts in the form of off-gases, including carbon monoxide, carbon dioxide, methane, ethane, propane, and / or butane.

[0031] Typically, the hydrogen used for RDU processes is supplied from hydrogen plants that employ steam methane reforming (SMR) processes, which convert methane into hydrogen and carbon dioxide. Methane is generally supplied as natural gas by utility companies. However, according to this disclosure, the hydrogen supply for RDU can be advantageously generated from renewable by-products produced during the biomass conversion to fuel. Off-gas is supplied from the RDU and then sent through a compressor to a hydrogen plant, where hydrocarbon molecules heavier than methane (e.g., ethane, propane, and butane) are first converted to methane in a pre-reforming reactor. As a result, the off-gas provides alternatively fully renewable biomass-derived hydrogen in the process of producing renewable fuel.

Claims

1. A method for generating hydrogen from off-gas, the method comprising the steps of obtaining the off-gas from a renewable diesel unit (RDU) having biomass raw materials, and feeding the off-gas into a steam methane reformer (SMR), wherein the hydrogen is produced through the use of the SMR, and the SMR is supplied with renewable hydrogen as fuel, CO ２ A method comprising capturing hydrogen from off-gas or synthesis gas originating from the SMR, subsequently feeding the hydrogen into the regenerative diesel unit (RDU) or a second regenerative diesel unit (RDU), wherein the SMR undergoes a pressure swing adsorption (PSA) process.

2. The method according to claim 1, wherein the off-gas is selected from the group consisting of carbon monoxide, carbon dioxide, methane, ethane, propane, butane, hydrogen, and any combination thereof, or the off-gas contains carbon monoxide, or the off-gas contains carbon dioxide, or the off-gas contains methane, or the off-gas contains ethane, or the off-gas contains propane, or the off-gas contains butane.

3. The method according to claim 1, wherein the off-gas is introduced into the SMR via a compressor.

4. A method for generating hydrogen from off-gas, wherein the method is - The step of obtaining the off-gas from a renewable diesel unit (RDU) having biomass raw materials, - A step of introducing the off-gas into a pre-reforming reactor to produce methane, - The process includes the step of introducing the methane into a steam methane reformer (SMR), wherein hydrogen is produced from the methane, and subsequently the hydrogen is introduced into the renewable diesel unit (RDU) or a second renewable diesel unit (RDU), and the SMR is supplied with renewable hydrogen as fuel, CO ２ A method comprising a pressure swing adsorption (PSA) process, wherein the SMR is captured from off-gas or synthesis gas originating from the SMR.

5. The method according to claim 4, wherein the off-gas is introduced into the pre-reforming reactor via a compressor.

6. A method for supplying hydrogen to a renewable diesel unit (RDU) having biomass as a raw material, the method comprising the steps of: obtaining off-gas from the RDU; converting the off-gas to hydrogen, wherein the hydrogen is produced via a steam methane reformer (SMR); and subsequently supplying the hydrogen to the RDU, wherein the SMR is supplied with renewable hydrogen as fuel, CO ２ A method comprising a pressure swing adsorption (PSA) process, wherein the SMR is captured from off-gas or synthesis gas originating from the SMR.

7. The method according to claim 6, wherein the conversion of the off-gas to hydrogen includes the step of introducing the off-gas into a pre-reforming reactor to produce methane.

8. The method according to claim 7, wherein the methane is introduced into the SMR and the hydrogen is produced from the methane.

9. The method according to claim 4, wherein the off-gas is introduced into the SMR via a compressor.

10. The aforementioned CO ２ The method according to claim 4, wherein the materials are collected, compressed and transported or isolated individually or collectively for use as chemical raw materials.

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