Method and system for integrating petrochemical and refinery operations

Abstract

Systems and methods for integrating petrochemical and refinery operations. One such method includes collecting a hydrogen-rich gas stream produced as a by-product of a petrochemical operation at a petrochemical plant and purifying the hydrogen-rich gas stream to produce a purified hydrogen gas stream. This process further comprises supplying the purified hydrogen stream to a hydrotreating unit or a hydrocracking unit at a refinery, and collecting an ethane-rich gas stream produced as a byproduct of refinery operation at the refinery, such that the ethane-rich gas stream can be supplied to a steam cracker at the petrochemical plant to produce olefins such as ethylene and propylene.

Description

Technical Field

[0001] The present invention generally relates to systems and methods for integrating petrochemical and refinery operations. More specifically, the present invention relates to systems and methods for collecting a hydrogen-rich gas stream that is generated as a by-product or waste gas during petrochemical equipment operation and supplying the hydrogen gas stream to a hydrotreating unit or hydrocracking unit in a refinery, while also collecting an ethane-rich gas stream that is generated as a by-product or waste gas during refinery operation and supplying the ethane gas stream to an ethane steam cracker at the petrochemical equipment, thereby maximizing the production of olefins (such as ethylene and / or propylene) at the petrochemical equipment while reducing refinery energy requirements. Background Art

[0002] Hydrogen (H 2 ) can be generated in-situ during several petrochemical equipment operations, including chlor-alkali production, ethane steam cracking, methyl tert-butyl ether (MTBE) production, propane and butane dehydrogenation, and catalytic reforming. Specifically, hydrogen can be generated as a by-product along with other light gases in the form of a hydrogen-rich waste gas stream (which typically has a hydrogen content of about 80 mole% to about 90 mole%). Generally, the excess hydrogen-rich gas stream generated at the petrochemical equipment is typically burned or vented to the atmosphere. In contrast, a refinery may have a hydrogen manufacturing unit (HMU) for generating hydrogen from natural gas (NG) feedstock. The hydrogen generated by the HMU can be used in hydrotreating and hydrocracking operations in the refinery. However, the HMU operation in the refinery is energy and feedstock intensive. Therefore, there is a need to improve the efficiency or synergy of petrochemical and refining operations by utilizing waste from waste by-products, thereby reducing the total feedstock or energy requirements. Summary of the Invention

[0003] To address these and other drawbacks in the art, the applicant has developed systems and methods for integrating or synergizing petrochemical and refinery operations to meet one of several operational needs, such as improving efficiency, reducing waste, and increasing economic benefits.

[0004] In certain embodiments, a method for integrating petrochemical and refinery operations includes the following steps: collecting a hydrogen-rich gas stream or an excess hydrogen waste gas stream generated as a byproduct of petrochemical operations at petrochemical facilities; purifying the hydrogen-rich gas stream or the excess hydrogen waste gas stream to produce a purified hydrogen gas stream; supplying the purified hydrogen gas stream to a hydrotreating unit or a hydrocracking unit at a refinery; collecting an ethane-rich gas stream generated as a byproduct of refinery operations at the refinery; and supplying the ethane-rich gas stream to an ethane steam cracker at petrochemical facilities to produce ethylene. In at least some embodiments, the hydrogen-rich gas stream can be an exhaust gas byproduct generated by petrochemical operations, and the ethane-rich gas stream can be an exhaust gas generated by refinery operations. In some embodiments of the method, substantially all of the hydrogen (which would typically be wasted or burned) generated as a byproduct of petrochemical operations at petrochemical facilities is collected and supplied to a hydrotreating unit or a hydrocracking unit at a refinery to reduce the natural gas or other energy requirements of one or more refinery operations.

[0005] In certain embodiments, the petrochemical operations can be chlor-alkali production, ethane steam cracking, methyl tert-butyl ether (MTBE) production, propane and butane dehydrogenation, catalytic reforming, or any combination thereof. In some embodiments, the refinery operations can include cracking operations such as fluid catalytic cracking.

[0006] In some embodiments, the hydrogen-rich gas stream can be processed and purified by a pressure swing adsorption unit or by a guard bed. In some embodiments, the purified hydrogen gas stream contains 99.9 wt% hydrogen. The purified hydrogen gas stream can contain greater than 90 wt% hydrogen, or greater than 95 wt% hydrogen, or greater than 98 wt% hydrogen, or at least 99 wt% hydrogen or at least 99.9 wt% hydrogen.

[0007] In some embodiments, prior to the step of supplying the purified hydrogen gas stream to a hydrotreating unit or a hydrocracking unit, the method can include mixing the purified hydrogen gas stream with a hydrogen gas stream generated by a hydrogen production unit at the refinery to produce a combined hydrogen gas stream. In such embodiments, the combined hydrogen gas stream can be supplied to a hydrotreating unit or a hydrocracking unit. In at least some cases, the hydrotreating unit or the hydrocracking unit can be connected to the hydrogen production unit.

[0008] In at least some embodiments, the method can include reducing the demand load on a hydrogen production unit in a refinery in response to supplying a purified hydrogen gas stream to a hydrotreating unit or a hydrocracking unit in the refinery. In some embodiments, the method can further include reducing the natural gas consumption at a hydrogen production unit connected to the hydrotreating unit or the hydrocracking unit in the refinery in response to supplying the purified hydrogen gas stream to the hydrotreating unit or the hydrocracking unit. In at least some embodiments, the method can further include reducing the carbon dioxide emissions at a hydrogen production unit connected to the hydrotreating unit or the hydrocracking unit in the refinery in response to supplying the purified hydrogen gas stream to the hydrotreating unit or the hydrocracking unit. Embodiments can include supplying an ethane-rich gas stream to an ethane steam cracker located at petrochemical equipment to produce propylene and ethylene.

[0009] The present invention also provides an integrated system for petrochemical and refinery operations. The system can include petrochemical equipment and refinery units. The petrochemical equipment can include a hydrogen waste gas collection unit operable to collect a hydrogen-rich gas stream generated as a byproduct of petrochemical operations. The petrochemical equipment can further include a hydrogen waste gas purification unit (operable to purify the hydrogen-rich gas stream to produce a purified hydrogen gas stream) and an ethane steam cracker (operable to receive an ethane-rich gas stream). The refinery units can include a hydrotreating unit or a hydrocracking unit (operable to receive the purified hydrogen gas stream from the hydrogen waste gas purification unit) and an ethane waste gas collection unit (operable to collect an ethane-rich gas stream generated as a byproduct of refinery operations and in fluid communication with the ethane steam cracker).

[0010] In at least some embodiments, the hydrogen-rich gas stream can be a waste gas byproduct generated by petrochemical operations, and the ethane-rich gas stream can be a waste gas generated by refinery operations. In some embodiments, the refinery operations can include cracking operations such as fluid catalytic cracking.

[0011] In some embodiments, the petrochemical equipment can further include at least one processing unit selected from the following: a chlor-alkali production unit, an ethane steam cracking unit, a methyl tert-butyl ether (MTBE) production unit, a propane and butane dehydrogenation unit, a catalytic reforming unit, and any combination thereof. Thus, in at least some embodiments, the petrochemical operations in the system can be chlor-alkali production, ethane steam cracking, methyl tert-butyl ether (MTBE) production, propane and butane dehydrogenation, catalytic reforming, or any combination thereof. At least one processing unit can be connected to the hydrogen waste gas collection unit.

[0012] In some embodiments, the hydrogen offgas purification unit can include a pressure swing adsorption unit or one or more guard beds. The purified hydrogen stream can contain greater than 90 wt% hydrogen, or greater than 95 wt% hydrogen, or greater than 98 wt% hydrogen, or at least 99 wt% hydrogen or at least 99.9 wt% hydrogen.

[0013] In some embodiments, the refinery can further include a hydrogen production unit operable to produce hydrogen from natural gas. The hydrogen production unit (HMU) can be connected to a hydrotreating unit or a hydrocracking unit. The hydrotreating unit or the hydrocracking unit can be operated to receive the purified hydrogen stream to reduce the demand load on the hydrogen production unit. In some embodiments, the hydrotreating unit or the hydrocracking unit can be operably configured to receive a hydrogen fuel mixture comprising the purified hydrogen stream or a portion thereof and a hydrogen stream produced by the hydrogen production unit.

[0014] Embodiments of the system include a hydrotreating unit or a hydrocracking unit operable to receive the purified hydrogen stream, thereby reducing natural gas consumption or carbon dioxide emissions at the hydrogen production unit.

[0015] In at least some embodiments, an ethane steam cracker is operable to produce ethylene and propylene from an ethane-rich stream, and an ethane offgas collection unit is operable to send the ethane-rich stream to the ethane steam cracker at a petrochemical facility.

[0016] These and other aspects and advantages of these exemplary embodiments and other embodiments have been discussed in detail herein. Additionally, it should be understood that both the foregoing information and the following detailed description merely provide illustrative examples of various aspects and embodiments and are intended to provide an overview or framework for understanding the nature and characteristics of the claimed aspects and embodiments. Accordingly, these and other objects, advantages, and features of the invention will become apparent by reference to the following specification and drawings. Additionally, it should be understood that the features of the various embodiments described herein are not mutually exclusive and can exist in various combinations and permutations. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings (which are included to provide a further understanding of the embodiments of the invention) are incorporated in and constitute a part of this specification, which illustrate embodiments of the invention and, together with the detailed description, are used to explain the principles of the embodiments discussed herein. No attempt is made to show the structural details of the invention in more detail than is necessary for a fundamental understanding of the embodiments discussed herein and the various ways in which they may be practiced. By convention, the various features of the drawings discussed below are not necessarily drawn to scale. The dimensions of the various features and elements in the drawings may be enlarged or reduced to more clearly show the embodiments of the invention.

[0018] Figure 1 It is a diagram of a system for integrating petrochemical and refinery operations according to an exemplary embodiment of the present invention. Detailed implementation manners

[0019] The present invention describes various embodiments, which relate to processes, methods and systems for integrating petrochemical and refinery operations. Additional embodiments may be described and disclosed.

[0020] In the following description, numerous details are set forth in order to provide a thorough understanding of the various embodiments. In other instances, well-known processes, devices and systems have not been described in particular detail so as not to unnecessarily obscure the various embodiments. Additionally, the description of the various embodiments may omit certain features or details so as not to obscure the various embodiments.

[0021] The description may use the phrases "in some embodiments", "in various embodiments", "in one embodiment" or "in embodiments", which may each refer to one or more of the same or different embodiments. In addition, the terms "comprising", "including", "having", etc. used with respect to the embodiments of the present invention are synonymous.

[0022] The term "about" refers to a range of values including the specified value, which those skilled in the art would consider reasonably similar to the specified value. In an embodiment, "about" refers to a value within the standard deviation of measurements commonly acceptable in the art. In a non-limiting embodiment, when the term "about" is used with a specific value, then "about" refers to a range extending from ±10% of the specified value, alternatively ±5% of the specified value, or alternatively ±1% of the specified value, or alternatively ±0.5% of the specified value. In an embodiment, "about" refers to the specified value.

[0023] When used in the claims and / or the description, the terms "reduce", "reduced" or any variant thereof include any measurable reduction or complete elimination to achieve the desired result.

[0024] When used in conjunction with any of the terms "comprising", "including", "containing" or "having" in the claims or the description, the words "a" or "an" may mean "one", but it is also consistent with the meanings of "one or more", "at least one", and "one or more than one". The terms "weight %", "volume %" or "mole %" refer respectively to the weight, volume or mole percentage of a component, based on the total weight, total volume or total moles of the material including the component. In a non-limiting example, 10 grams of a component in 100 grams of material is 10 weight % of such component.

[0025] The terms "comprising" (and any form of comprising, such as "comprises" and "comprising"), "having" (and any form of having, such as "has" and "having"), "including" (and any form of including, such as "includes" and "including"), or "containing" (and any form of containing, such as "contains" and "containing") are inclusive or open-ended and do not exclude additional, unrecited elements or method steps.

[0026] Systems and methods for integrating petrochemical and refinery operations are disclosed herein. Specifically, the systems and methods disclosed herein provide for the co-use of waste gas as a feed stream in petrochemical and refinery operations, thereby maximizing the production of light olefins at petrochemical facilities while reducing the energy requirements of the refinery. More specifically, the present invention relates to systems and methods for collecting an excess hydrogen-rich gas stream generated as a byproduct or waste gas during petrochemical facility operations and supplying the hydrogen gas stream to a hydrotreating unit or hydrocracking unit at the refinery, and also collecting an ethane-rich gas stream generated as a byproduct or waste gas during refinery operations and supplying the ethane gas stream to an ethane steam cracker at the petrochemical facility.

[0027] Figure 1 is a schematic diagram that depicts a system 500 for integrating petrochemical and refinery operations according to an exemplary embodiment of the present invention. As Figure 1 shown, the system 500 may include a petrochemical facility 100 and a refinery unit 200. The petrochemical facility 100 may include one or more petrochemical operations 110 capable of generating hydrogen waste gas 105. Non-limiting examples of petrochemical operations 110 may include chlor-alkali production operations, ethane steam cracking operations, methyl tert-butyl ether (MTBE) production operations, propane and butane dehydrogenation operations, and catalytic reforming operations. In at least some embodiments, one or more petrochemical operations 110 at the petrochemical facility 100 may be in the form of a processing unit 110 selected from the following: chlor-alkali production unit, ethane steam cracking unit, methyl tert-butyl ether (MTBE) production unit, propane and butane dehydrogenation unit, catalytic reforming unit, and any combination thereof.

[0028] In at least some embodiments, the processing unit 110 may be an electrified cracker that generates a large amount of excess hydrogen waste gas. For example, the electrified cracker may be used as part of a decarbonization strategy at the petrochemical facility. In such a case, the large amount of excess hydrogen waste gas generated by the electrified cracker may not be usable as fuel within the cracker complex. The present invention provides a system 500 having improved hydrogen waste gas utilization, which increases the efficiency of the system 500.

[0029] The petrochemical equipment 100 may include a hydrogen waste gas collection unit 150 connected to one or more petrochemical operations 110 or processing units 110. The hydrogen waste gas collection unit 150 is operable to collect a hydrogen-rich waste gas stream 105 generated as a by-product of the operation of the petrochemical operation 110 or processing unit 110. Depending on the process technology and feed characteristics employed, the hydrogen-rich waste gas stream 105 will be contaminated with salts, chlorides, alkanes, alkenes, and other contaminants. The system 500 of the present invention includes components for purifying the hydrogen-rich waste gas stream 105 so that it is suitable for utilization in hydrotreating or hydrocracking operations in a refinery, rather than burning or discarding the hydrogen-rich waste gas stream 105

[0030] Accordingly, the petrochemical equipment 100 may further include a hydrogen waste gas purification unit 120 connected to the hydrogen waste gas collection unit 150. The hydrogen waste gas purification unit 120 is operable to purify the hydrogen-rich waste gas stream 105 collected by the hydrogen waste gas collection unit 150 to produce a purified hydrogen gas stream 125. In some embodiments, the hydrogen waste gas purification unit 120 may include a pressure swing adsorption unit and / or one or more guard beds. The purified hydrogen gas stream 125 may contain greater than 90 wt% hydrogen, or greater than 95 wt% hydrogen, or greater than 98 wt% hydrogen, or at least 99 wt% hydrogen or at least 99.9 wt% hydrogen.

[0031] As Figure 1 shown, the petrochemical equipment 100 may further include an ethane steam cracker 130, which is operable to receive an ethane-rich gas stream and produce light olefins 135 such as ethylene and propylene.

[0032] The refinery unit 200 may include a hydrotreating or hydrocracking unit 230, which is operable to receive a hydrogen gas stream. For example, the hydrocracking unit 230 may be configured to upgrade and process a vacuum gas oil feedstock by cracking while injecting hydrogen to produce diesel or kerosene products. To supply the hydrogen gas stream 227 to the hydrotreating or hydrocracking unit 230, the refinery unit 200 may include a hydrogen manufacturing unit (HMU) 220, which is operable to produce a hydrogen gas stream 225 from natural gas, naphtha, and / or liquefied petroleum gas (LPG) feedstocks 210. Specifically, the HMU 220 is operable to receive a natural gas or fuel feed stream 215 and produce a hydrogen gas stream 225. The hydrogen manufacturing unit (HMU) 220 may be connected to the hydrotreating unit or hydrocracking unit 230 to feed the hydrogen gas stream 227 to the hydrotreating or hydrocracking unit 230.

[0033] The hydrotreating unit or hydrocracking unit 230 is operably configured to receive a purified hydrogen gas stream 125 generated by the hydrogen waste gas purification unit 120 at the petrochemical facility 100, so as to reduce the demand load on the hydrogen production unit 220. Accordingly, the system 500 includes components for transporting the purified hydrogen gas stream 125 from the petrochemical facility 100 to the hydrotreating or hydrocracking unit 230 at the refinery 200. The components for transporting the purified hydrogen gas stream 125 from the petrochemical facility 100 to the hydrotreating or hydrocracking unit 230 at the refinery 200 may include any components known in the art, including pipelines or vehicle transportation, such as by truck or railcar, and may include any necessary intermediate facilities or storage tanks. In some embodiments, the hydrotreating or hydrocracking unit 230 may be operably configured to receive a hydrogen fuel mixture 227 that includes the purified hydrogen gas stream 125 or a portion thereof generated at the petrochemical facility 100 and the hydrogen gas stream 225 generated by the hydrogen production unit 220. In at least some embodiments, the system 500 includes a hydrotreating or hydrocracking unit 230 that is operable to receive the purified hydrogen gas stream 125 from the petrochemical facility 100 in order to reduce natural gas consumption or carbon dioxide emissions at the hydrogen production unit 220.

[0034] The refinery unit 200 may further include one or more refinery operations 240 capable of generating an ethane-rich waste gas stream 242. In some embodiments, the refinery operation 240 may include cracking operations, such as fluid catalytic cracking. The refinery unit 200 may further include an ethane waste gas collection unit 250 that is operable to collect the ethane-rich gas stream 242 generated as a by-product of the refinery operation 240. A portion 248 of the ethane-rich waste gas 245 collected by the ethane waste gas collection unit may be used as fuel in the refinery fuel gas header. However, as Figure 1 shown, a portion 247 of the ethane-rich waste gas stream 245 from the ethane waste gas collection unit 250 is transferred as a feedstock to the ethane cracker 130 at the petrochemical facility 100.

[0035] The ethane steam cracker 130 at the petrochemical facility 100 is operably configured to receive an ethane-rich waste stream 247 or a portion thereof from the ethane waste gas collection unit 250 at the refinery unit 200 and / or the refinery operation 240. The ethane stream cracker 130 is further operably configured to produce light olefins such as ethylene and propylene from the ethane-rich gas stream 247 received from the refinery unit 200. Accordingly, the system 500 includes means for transporting the ethane-rich gas stream 245 from the ethane waste gas collection unit 250 or the refinery operation 240 at the refinery 200 to the ethane steam cracker 130 at the petrochemical facility 100. The means for transporting the ethane-rich gas stream 245 from the refinery 200 to the ethane steam cracker 130 at the petrochemical facility 100 may include any means known in the art, including pipeline or vehicular transport, such as by truck or railcar, and may include any necessary intermediate facilities or storage tanks. In at least some embodiments, the ethane waste gas collection unit 250 may be in fluid communication with the ethane steam cracker 130. In some embodiments, the ethane waste gas collection unit 250 is operable to deliver the ethane-rich gas stream 245 to the ethane steam cracker 130 at the petrochemical facility 100. The disclosed system 500 is operable to increase the production of light olefins at the petrochemical facility 100 by providing to the ethane stream cracker 130 an additional ethane-rich gas stream sourced from the waste gas by-products of one or more refinery operations 240.

[0036] In at least some embodiments, a portion of the ethane waste gas 248 from the ethane waste gas collection unit 250 or the refinery operation 240 may be used to supply the refinery fuel gas header. A portion 217 of the natural gas and fuel feed 215 to the hydrogen production unit 220 may also be diverted to supply the fuel gas header at the refinery 200.

[0037] In some embodiments, the hydrogen waste gas generated at the petrochemical facility 100 or the purified hydrogen gas stream produced therefrom may be replaced with an ethane-rich waste gas generated by one or more refinery operations 240 at the refinery 200 that is energetically or economically equivalent. In this manner, a synergy may be established between the operation of the petrochemical facility 100 and the operation of the refinery 200.

[0038] By Figure 1The system described herein illustrates a method for integrating petrochemical and refinery operations. For example, the method can include collecting a hydrogen-rich gas stream 105 generated as a by-product of petrochemical operations 110 at petrochemical equipment 100, and purifying the hydrogen-rich gas stream to produce a purified hydrogen gas stream 125. The method can further include supplying the purified hydrogen gas stream 125 to a hydrotreating unit or a hydrocracking unit 230 in a refinery 200, and collecting an ethane-rich gas stream 242 generated as a by-product of refinery operations 240 in the refinery 200. The method can further include supplying the ethane-rich gas stream 247 or a portion thereof to an ethane steam cracker 130 at the petrochemical equipment 100 to produce light olefins such as ethylene and propylene.

[0039] The present invention provides systems and methods for integrating petrochemical and refinery operations to increase ethylene and / or propylene production at petrochemical equipment while reducing the energy requirements at the refinery. Specifically, the present invention provides a method for integrating petrochemical and refinery operations, the method comprising: collecting an excess hydrogen-rich waste gas stream generated as a by-product of petrochemical operations at petrochemical equipment; purifying the hydrogen-rich gas stream to produce a purified hydrogen gas stream; supplying the purified hydrogen gas stream to a hydrotreating unit or a hydrocracking unit in a refinery; collecting an ethane-rich gas stream generated as a by-product of refinery operations in the refinery; and supplying the ethane-rich gas stream to an ethane steam cracker at petrochemical equipment to produce ethylene. The petrochemical operations in the foregoing method embodiments can be selected from chlor-alkali production, ethane steam cracking, methyl tert-butyl ether (MTBE) production, propane and butane dehydrogenation, catalytic reforming, and any combination thereof.

[0040] In the foregoing method embodiments, the hydrogen-rich gas stream can be purified by processing the hydrogen-rich gas stream through a pressure swing adsorption unit. In the foregoing method embodiments, the hydrogen-rich gas stream can be purified by processing the hydrogen-rich gas stream through a guard bed. In the foregoing method embodiments, the purified hydrogen gas stream can contain at least 99.9 wt% hydrogen.

[0041] The foregoing method embodiments can further include reducing the demand load on a hydrogen production unit in the refinery in response to supplying the purified hydrogen gas stream to a hydrotreating unit or a hydrocracking unit. The foregoing method embodiments can further include, prior to the step of supplying the purified hydrogen gas stream to a hydrotreating unit or a hydrocracking unit, mixing the purified hydrogen gas stream with a hydrogen gas stream generated by a hydrogen production unit in the refinery to produce a combined hydrogen gas stream, and feeding the combined hydrogen gas stream to a hydrotreating unit or a hydrocracking unit. In the foregoing method embodiments, the hydrotreating unit or the hydrocracking unit can be connected to the hydrogen production unit.

[0042] The foregoing method embodiments may further include reducing natural gas consumption at a hydrogen production unit connected to a hydrotreating unit or a hydrocracking unit in a refinery in response to supplying a purified hydrogen gas stream to the hydrotreating unit or the hydrocracking unit. The foregoing method embodiments may further include reducing carbon dioxide emissions at a hydrogen production unit connected to a hydrotreating unit or a hydrocracking unit in a refinery in response to supplying a purified hydrogen gas stream to the hydrotreating unit or the hydrocracking unit.

[0043] In the foregoing method embodiments, the hydrogen-rich gas stream may be an exhaust byproduct generated from petrochemical operations. In the foregoing method embodiments, the refinery operations may include cracking operations. In the foregoing method embodiments, the cracking operations may be fluid catalytic cracking. In the foregoing method embodiments, the ethane-rich gas stream may be an exhaust gas generated from refinery operations. In the foregoing method embodiments, supplying the ethane-rich gas stream to an ethane steam cracker located at petrochemical equipment may produce propylene and ethylene.

[0044] The present invention also provides an integrated system for petrochemical and refinery operations, which is operable to increase the production of ethylene and / or propylene at petrochemical equipment while reducing the energy requirements of the refinery. The integrated system for petrochemical and refinery operations may include: petrochemical equipment, which includes: a hydrogen waste gas collection unit, which is operable to collect a hydrogen-rich gas stream generated as a byproduct of petrochemical operations; a hydrogen waste gas purification unit, which is operable to purify the hydrogen-rich gas stream to produce a purified hydrogen gas stream; and an ethane steam cracker, which is operable to receive an ethane-rich gas stream; and a refinery unit, which includes: a hydrotreating unit or a hydrocracking unit, which is operable to receive the purified hydrogen gas stream from the hydrogen waste gas purification unit; and an ethane waste gas collection unit, which is operable to collect an ethane-rich gas stream generated as a byproduct of refinery operations and is in fluid communication with the ethane steam cracker.

[0045] In the foregoing system embodiments, the petrochemical operations may be chlor-alkali production, ethane steam cracking, methyl tert-butyl ether (MTBE) production, propane and butane dehydrogenation, catalytic reforming, or any combination thereof. The petrochemical equipment in the foregoing system embodiments may further include at least one processing unit selected from the following: a chlor-alkali production unit, an ethane steam cracking unit, a methyl tert-butyl ether (MTBE) production unit, a propane and butane dehydrogenation unit, a catalytic reforming unit, or any combination thereof, and at least one processing unit is connected to the hydrogen waste gas collection unit.

[0046] In the foregoing system embodiments, the hydrogen waste gas purification unit may include a pressure swing adsorption unit. In the foregoing system embodiments, the hydrogen waste gas purification unit may include one or more guard beds. In the foregoing system embodiments, the purified hydrogen gas stream may contain at least 99.9 wt% hydrogen. The refinery in the foregoing system embodiments may further include a hydrogen production unit, which may be operable to produce hydrogen from natural gas and is connected to a hydrotreating unit or a hydrocracking unit. In the foregoing system embodiments, the hydrotreating unit or the hydrocracking unit may be operable to receive the purified hydrogen gas stream to reduce the demand load on the hydrogen production unit. In the foregoing system embodiments, the hydrotreating unit or the hydrocracking unit may be operable to receive a hydrogen fuel mixture that includes the purified hydrogen gas stream or a portion thereof and a hydrogen gas stream produced by the hydrogen production unit.

[0047] In the foregoing system embodiments, the hydrotreating unit or the hydrocracking unit may be operable to receive the purified hydrogen gas stream and reduce the natural gas consumption at the hydrogen production unit. In the foregoing system embodiments, the hydrotreating unit or the hydrocracking unit may be operable to receive the purified hydrogen gas stream and reduce the carbon dioxide emissions at the hydrogen production unit. In the foregoing system embodiments, the hydrogen-rich gas stream may be waste gas generated from petrochemical operations.

[0048] In the foregoing system embodiments, the ethane steam cracker may be operable to produce ethylene and propylene from an ethane-rich gas stream. In the foregoing system embodiments, the refinery operation may be a cracking operation. In the foregoing system embodiments, the cracking operation may be fluid catalytic cracking. In the foregoing system embodiments, the ethane waste gas collection unit may be operable to send the ethane-rich gas stream to the ethane steam cracker at the petrochemical facility.

[0049] The present invention also provides a method for integrating petrochemical and refinery operations, which results in an increase in the production of ethylene and / or propylene at the petrochemical facility while reducing the energy requirements of the refinery. Specifically, the present invention provides a method for integrating petrochemical and refinery operations, the method comprising: collecting a hydrogen-rich gas stream generated as a by-product of petrochemical operations at the petrochemical facility; purifying the hydrogen-rich gas stream to produce a purified hydrogen gas stream; supplying the purified hydrogen gas stream to a hydrotreating unit or a hydrocracking unit at the refinery; collecting an ethane-rich gas stream generated as a by-product of refinery operations at the refinery; and supplying the ethane-rich gas stream to the ethane steam cracker at the petrochemical facility to produce ethylene. The petrochemical operations in the foregoing method embodiments may be selected from chlor-alkali production, ethane steam cracking, methyl tert-butyl ether (MTBE) production, propane and butane dehydrogenation, catalytic reforming, and any combination thereof.

[0050] In any of the foregoing method embodiments, the hydrogen-rich gas stream can be processed by a pressure swing adsorption unit to purify the hydrogen-rich gas stream. In any of the foregoing method embodiments, the hydrogen-rich gas stream can be processed by a guard bed to purify the hydrogen-rich gas stream. In any of the foregoing method embodiments, the purified hydrogen gas stream can contain at least 99.9 wt% hydrogen.

[0051] Any of the foregoing method embodiments can further include reducing the demand load on the hydrogen production unit in the refinery in response to supplying the purified hydrogen gas stream to a hydrotreating unit or a hydrocracking unit. Any of the foregoing method embodiments can further include, prior to the step of supplying the purified hydrogen gas stream to a hydrotreating unit or a hydrocracking unit, mixing the purified hydrogen gas stream with a hydrogen gas stream generated by a hydrogen production unit in the refinery to produce a combined hydrogen gas stream and feeding the combined hydrogen gas stream to a hydrotreating unit or a hydrocracking unit. In any of the foregoing method embodiments, the hydrotreating unit or the hydrocracking unit can be connected to the hydrogen production unit.

[0052] Any of the foregoing method embodiments can further include reducing the natural gas consumption at the hydrogen production unit in the refinery connected to the hydrotreating unit or the hydrocracking unit in response to supplying the purified hydrogen gas stream to the hydrotreating unit or the hydrocracking unit. Any of the foregoing method embodiments can further include reducing the carbon dioxide emissions at the hydrogen production unit in the refinery connected to the hydrotreating unit or the hydrocracking unit in response to supplying the purified hydrogen gas stream to the hydrotreating unit or the hydrocracking unit.

[0053] In any of the foregoing method embodiments, the hydrogen-rich gas stream can be an exhaust by-product generated by petrochemical operations. In any of the foregoing method embodiments, the refinery operations can include cracking operations. In any of the foregoing method embodiments, the cracking operation can be fluid catalytic cracking. In any of the foregoing method embodiments, the ethane-rich gas stream can be an exhaust gas generated by refinery operations. In any of the foregoing method embodiments, supplying the ethane-rich gas stream to an ethane steam cracker located at petrochemical equipment can produce ethylene and propylene.

[0054] The present invention also provides an integrated system for petrochemical and refinery operations, which is operable to increase the production of ethylene and / or propylene at petrochemical facilities while reducing the energy requirements of the refinery. The integrated system for petrochemical and refinery operations may include: a petrochemical facility, which includes: a hydrogen off-gas collection unit, which is operable to collect a hydrogen-rich gas stream generated as a by-product of petrochemical operations; a hydrogen off-gas purification unit, which is operable to purify the hydrogen-rich gas stream to produce a purified hydrogen gas stream; and an ethane steam cracker, which is operable to receive an ethane-rich gas stream; and a refinery unit, which includes: a hydrotreating unit or a hydrocracking unit, which is operable to receive the purified hydrogen gas stream from the hydrogen off-gas purification unit; and an ethane off-gas collection unit, which is operable to collect an ethane-rich gas stream generated as a by-product of refinery operations and is in fluid communication with the ethane steam cracker.

[0055] In the foregoing system embodiments, the petrochemical operations may be chlor-alkali production, ethane steam cracking, methyl tert-butyl ether (MTBE) production, propane and butane dehydrogenation, catalytic reforming, or any combination thereof. The petrochemical facility in any of the foregoing system embodiments may further include at least one processing unit selected from the following: a chlor-alkali production unit, an ethane steam cracking unit, a methyl tert-butyl ether (MTBE) production unit, a propane and butane dehydrogenation unit, a catalytic reforming unit, or any combination thereof, with at least one processing unit connected to the hydrogen off-gas collection unit.

[0056] In any of the foregoing system embodiments, the hydrogen off-gas purification unit may include a pressure swing adsorption unit. In any of the foregoing system embodiments, the hydrogen off-gas purification unit may include one or more guard beds. In any of the foregoing system embodiments, the purified hydrogen gas stream may contain at least 99.9 wt% hydrogen. The refinery in any of the foregoing system embodiments may further include a hydrogen production unit, which is operable to produce hydrogen from natural gas and is connected to the hydrotreating unit or the hydrocracking unit. In any of the foregoing system embodiments, the hydrotreating unit or the hydrocracking unit may be operable to receive the purified hydrogen gas stream to reduce the demand load on the hydrogen production unit. In any of the foregoing system embodiments, the hydrotreating unit or the hydrocracking unit is operable to receive a hydrogen fuel mixture, which includes the purified hydrogen gas stream or a portion thereof, and a hydrogen gas stream generated by the hydrogen production unit.

[0057] In any of the foregoing system embodiments, the hydrotreating unit or the hydrocracking unit can be operable to receive a purified hydrogen stream and reduce natural gas consumption at the hydrogen production unit. In any of the foregoing system embodiments, the hydrotreating unit or the hydrocracking unit can be operable to receive a purified hydrogen stream and reduce carbon dioxide emissions at the hydrogen production unit. In any of the foregoing system embodiments, the hydrogen-rich stream can be an exhaust gas generated by petrochemical operations.

[0058] In any of the foregoing system embodiments, the ethane steam cracker can be operable to produce ethylene and propylene from an ethane-rich stream. In any of the foregoing system embodiments, the refinery operation can be a cracking operation. In any of the foregoing system embodiments, the cracking operation can be a fluid catalytic cracking. In any of the foregoing system embodiments, the ethane waste gas collection unit can be operable to send the ethane-rich stream to the ethane steam cracker at the petrochemical facility.

[0059] Examples

[0060] The examples provided below illustrate selected aspects of various methods and systems for integrating petrochemical facilities and refinery operations.

[0061] Example 1

[0062] Implementation Figure 1 An exemplary embodiment of the provided system, in addition to providing additional feedstock to the ethane cracker at the petrochemical facility, results in a quantifiable savings in the natural gas demand for the hydrogen production unit (HMU), and a corresponding reduction in CO 2 emissions due to the reduced load on the HMU. Specifically, implementing the system disclosed in the present invention generates 70 tons per day (t / d) of hydrogen waste gas 105 from petrochemical facility operation 110, which results in a purified hydrogen stream 125 of 56 t / d, which can be used as feed to the hydrotreating or hydrocracking unit 230 in refinery 200. Even after replenishing the fuel gas header in the refinery with natural gas, the resulting reduced demand for the HMU 220 saves 90 t / d of natural gas. At the same time, implementing the system and method of the present invention generates 160 t / d of ethane-rich refinery waste gas, which is generated by refinery operation 140 and can be used as feed to the ethane cracker 130 at petrochemical facility 100. This results in a direct savings of approximately 90 t / d of natural gas (which would otherwise be fed to the hydrogen production unit), resulting in a reduction in carbon dioxide emissions of approximately 200 t / d.

[0063] When the scope disclosed herein is concerned, any lower limit range can be combined with any upper limit to enumerate ranges not explicitly recited, and any lower limit range can be combined with any other lower limit to enumerate ranges not explicitly recited. In the same way, any upper limit range can be combined with any other upper limit to enumerate ranges not explicitly recited. Additionally, references to values recited in a range include each and every value within that range, even if not explicitly recited. Thus, each point or single value can be used as its own lower or upper limit, in combination with any other point or single value or any other lower or upper limit, to enumerate ranges not explicitly recited.

[0064] Other objects, features, and advantages of the present invention will become apparent from the foregoing drawings, detailed description, and examples. These drawings, detailed description, and examples, although representing specific embodiments of the present invention, are given by way of illustration only and are not meant to be limiting. In additional embodiments, features from specific embodiments can be combined with features from other embodiments. For example, features from one embodiment can be combined with features from any other embodiment. In additional embodiments, additional features can be added to the specific embodiments described herein. It should be understood that although the present invention includes certain aspects, embodiments, and optional features, those skilled in the art can make changes, improvements, or variations to these aspects, embodiments, and optional features, and such changes, improvements, or variations are considered to be within the scope of the present invention.

Claims

1. A method for integrating petrochemical and refinery operations, the method comprising: collecting a hydrogen-rich gas stream generated as a by-product of petrochemical operations at petrochemical equipment; purifying the hydrogen-rich gas stream to produce a purified hydrogen gas stream; supplying the purified hydrogen gas stream to a hydrotreating unit or a hydrocracking unit in a refinery; collecting an ethane-rich gas stream generated as a by-product of refinery operations in the refinery; and supplying the ethane-rich gas stream to an ethane steam cracker at the petrochemical equipment to produce ethylene.

2. The method according to claim 1, wherein the petrochemical operations are selected from chlor-alkali production, ethane steam cracking, methyl tert-butyl ether (MTBE) production, propane and butane dehydrogenation, catalytic reforming, and any combination thereof.

3. The method according to claim 1 or claim 2, wherein the hydrogen-rich gas stream is processed by a pressure swing adsorption unit or a guard bed to purify the hydrogen-rich gas stream, and the purified hydrogen gas stream contains 99.9 wt% hydrogen.

4. The method according to any one of claims 1-3, which further comprises: responding to supplying the purified hydrogen gas stream to the hydrotreating unit or the hydrocracking unit, reducing the demand load on the hydrogen production unit in the refinery.

5. The method according to any one of claims 1-4, which further comprises: before the step of supplying the purified hydrogen gas stream to the hydrotreating unit or the hydrocracking unit, mixing the purified hydrogen gas stream with a hydrogen gas stream generated by the hydrogen production unit in the refinery to produce a combined hydrogen gas stream, and feeding the combined hydrogen gas stream into the hydrotreating unit or the hydrocracking unit; wherein the hydrotreating unit or the hydrocracking unit is connected to the hydrogen production unit.

6. The method according to any one of claims 1-5, which further comprises: responding to supplying the purified hydrogen gas stream to the hydrotreating unit or the hydrocracking unit, reducing the natural gas consumption at the hydrogen production unit in the refinery connected to the hydrotreating unit or the hydrocracking unit.

7. The method according to any one of claims 1-6, which further comprises: responding to supplying the purified hydrogen gas stream to the hydrotreating unit or the hydrocracking unit, reducing the carbon dioxide emissions at the hydrogen production unit in the refinery connected to the hydrotreating unit or the hydrocracking unit.

8. The method according to any one of claims 1-7, wherein the hydrogen-rich gas stream is an exhaust gas by-product generated by the petrochemical operations, wherein the ethane-rich gas stream is an exhaust gas generated by the refinery operations, and wherein supplying the ethane-rich gas stream to an ethane steam cracker located at the petrochemical equipment produces propylene as well as ethylene.

9. An integrated system for petrochemical and refinery operations, the system comprising: petrochemical equipment, which includes: a hydrogen waste gas collection unit operable to collect a hydrogen-rich gas stream generated as a by-product of petrochemical operations; a hydrogen waste gas purification unit operable to purify the hydrogen-rich gas stream to produce a purified hydrogen gas stream; and A steam cracker operable to receive an ethane-rich gas stream; and A refinery unit comprising: A hydrotreating unit or a hydrocracking unit operable to receive a purified hydrogen gas stream from the hydrogen waste gas purification unit; and An ethane waste gas collection unit operable to collect an ethane-rich gas stream generated as a by-product of refinery operations and in fluid communication with the steam cracker.

10. The system according to claim 9, wherein the petrochemical operation is selected from chlor-alkali production, ethane steam cracking, methyl tert-butyl ether (MTBE) production, propane and butane dehydrogenation, catalytic reforming, and any combination thereof.

11. The system according to claim 9 or claim 10, wherein the petrochemical equipment further Comprises: At least one processing unit selected from the following: a chlor-alkali production unit, an ethane steam cracking unit, a methyl tert-butyl ether (MTBE) production unit, a propane and butane dehydrogenation unit, a catalytic reforming unit, or any combination thereof, the at least one processing unit being connected to the hydrogen waste gas collection unit.

12. The system according to any one of claims 9-11, wherein the hydrogen waste gas purification unit comprises a pressure swing adsorption unit or one or more guard beds, and wherein the purified hydrogen gas stream comprises 99.9 wt% hydrogen.

13. The system according to any one of claims 9-12, wherein the refinery further Comprises: A hydrogen production unit operable to produce hydrogen from natural gas and connected to the hydrotreating unit or the hydrocracking unit, wherein the hydrotreating unit or the hydrocracking unit is operable to receive the purified hydrogen gas stream to reduce the demand load on the hydrogen production unit.

14. The system according to claim 22 or claim 23, wherein the hydrotreating unit or the hydrocracking unit is operable to receive a hydrogen fuel mixture comprising the purified hydrogen gas stream or a portion thereof and a hydrogen gas stream generated by the hydrogen production unit.

15. The system according to any one of claims 22-24, wherein the hydrotreating unit or the hydrocracking unit is operable to receive the purified hydrogen gas stream and reduce natural gas consumption or carbon dioxide emissions at the hydrogen production unit, wherein the steam cracker is operable to produce ethylene and propylene from the ethane-rich stream, and wherein the ethane waste gas collection unit is operable to send the ethane-rich stream to the steam cracker at the petrochemical equipment.

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