Flexible use of tail gas for intermittent power generation for electrified cracker furnaces

Abstract

This invention provides an energy management system for use with an electrified cracker (e-cracker) furnace, such as a bio-oil, naphtha or ethane cracker. The system comprises a feed comprised of a combustible tail gas obtained from an e-cracker furnace. A controller that monitors a supply of electrical power to an e-cracker and controls the feed. An electrical power generator is configured to utilise the combustible tail gas as a source of fuel and is in gaseous communication with the feed. In use, the controller is configured to detect or anticipate a deficit in the supply of electrical power to the e- cracker below a threshold level and when a deficit is detected or anticipated to supply the combustible tail gas to the electrical power generator in order to generate sufficient electrical power to compensate for the deficit in the supply of electrical power. Processes for operating an e-cracker furnace comprising the system are also provided.

Description

[0001]SP3095 - 1 - FLEXIBLE USE OF TAIL GAS FOR INTERMITTENT POWER GENERATION FOR ELECTRIFIED CRACKER FURNACES Field of the Invention 5 This invention relates to systems and processes for maintaining steady state operation of an electrified cracker (e-cracker). The systems and processes utilise electrically heated reactors and apparatus, wherein at least a portion of the electrical energy is provided from 10 renewable energy sources. Background of the Invention To address the considerable challenges of decarbonization of the global economy in order to meet net 15 zero targets within the 21st century, there has been an increasing trend towards adoption of more renewable sources of energy for industrial processes. Whilst improvements in energy usage efficiency and selection of renewable electrified manufacturing assets can help to20 reduce carbon footprint, certain processes, such as bio- oil, naphtha and ethane crackers, continue to produce waste streams such as methane and / or hydrogen rich cracker tail gases. Conventionally this tail gas was burned as fuel and used to power a range of refinery processes. 25 Notably, in cracking plants, around 90% of CO2 emissions are directly related to the energy consumption of the heat provision in the steam cracker. Consequently, with a move to electrification from renewable sources, the trend has been against utilising combustible tail gases exclusively 30 for combustion. An electricity power grid is a complex system consisting of buses and lines, where the buses may connect generators or loads and the lines link the buses to form a complex network structure. Ensuring a continuous grid power supply from renewable energy sources poses significant challenges rooted in the inherent variability and intermittency of these resources. Unlike traditional 5 fossil fuel-based power generation, renewables such as solar and wind are highly dependent on weather conditions and daylight availability. This intermittency leads to fluctuations in power output, creating an inherent instability in the grid. Cloud cover, nightfall, or 10 periods of low wind can result in sudden drops in energy production, requiring alternative sources to compensate for the deficit. The reasonable expectation is that both the average and number of fluctuations in electricity prices will increase in the future due to higher demand 15 and the increasing integration of renewables into the grid supply system. The mismatch between energy demand and supply becomes more pronounced as renewable penetration increases, demanding sophisticated energy storage and grid 20 management solutions. Energy storage technologies, such as batteries, face limitations in terms of scalability, cost, and efficiency, hindering their ability to store surplus energy during peak generation for use during periods of low production. Moreover, the decentralized nature of many 25 renewable sources, such as offshore wind turbines, complicates grid management, as their variable outputs are challenging to predict and synchronize. Addressing these issues requires advancements in energy storage technologies, grid flexibility enhancements, and the 30 development of smart power management systems to seamlessly integrate and balance the intermittent nature of renewable energy sources with the continuous demand for power. One way to mitigate the intermittent nature of renewable electricity supply is to adopt a flexible operation approach. The use of flexible operation in industry as a response to fluctuations in electricity 5 supply, and consequent pricing, is a practice commonly known as demand side management (DSM). One of the main challenges in the adoption of DSM, especially in the chemical industry, lies in the complexity and interdependency of the different processes; not 10 surprisingly, conventional chemical processes are typically operated under the optimal design conditions and ideally at a steady state. Hence, implementing process flexibility requires a more complex plant design and oversizing of the facility to enable the rapid ramps up 15 and down of production over time. WO2022 / 038230 relates to an electrified steam methane reformer (e-SMR). An electrical current is utilised for heating the e-SMR which may be supplemented with combustion of hydrogen rich reactor effluent in case 20 of intermittent grid power supply. The use of reactor effluent (a mix of high value product and tail gases) necessarily results in the potential for reduction in yield of the e-SMR, which represents a trade-off between the need to maintain continuous steady state operation 25 versus process efficiency. Hence, it would be desirable to identify improved ways to maintain steady state operation of e-cracker furnaces that are heavily reliant on renewable grid power. This could add considerable value and process efficiencies 30 and also contribute to the overall objective of reduction in carbon dioxide emissions. These and other objectives of the invention will become apparent to the skilled reader, providing a solution to these hitherto unmet needs. Summary of the Invention The present invention provides for systems and processes for the smart management of intermittent power from renewable sources for e-cracker furnaces through the 5 utilisation of combustible tail gases as a feed for rapid deployment power generation systems. In a first aspect the invention provides an energy management system for use with an electrified cracker (e- cracker) furnace, the system comprising: 10 a feed comprised of a combustible tail gas obtained from an e-cracker furnace; a controller that monitors a supply of electrical grid power to an e-cracker and also controls the feed; and an electrical power generator that is configured to 15 utilise the combustible tail gas as a source of fuel and is in gaseous communication with the feed; wherein the controller is configured to detect or anticipate a deficit in the supply of electrical grid power to the e-cracker below a threshold level and when a 20 deficit is detected or anticipated to supply the combustible tail gas to the electrical power generator in order to generate sufficient electrical power to compensate for the deficit in the supply of electrical grid power. Suitably, the combustible tail gas may 25 comprise methane, hydrogen or a combination of methane and hydrogen. In an embodiment of the invention the supply of electrical grid power comprises a proportion of electrical power derived from renewable sources. 30 In an embodiment the e-cracker furnace is selected from: a bio-oil cracker; a naphtha cracker; or an ethane cracker. In a further embodiment of the invention the controller is configured to divert the feed to a product stream if the supply of electrical grid power to the e- cracker rises above the threshold level. The product stream may be subject to interim or long term storage, if required. 5 In another embodiment of the invention, the electrical power generator is comprised of an array of modular power generating units. Suitably, the array of modular power generating units may be comprised of plurality of electricity generators configured so as to be 10 capable of rapid deployment. Typically, the plurality of electricity generators comprise at least one generator having rapid ramp up / ramp down capabilities. Optionally, the plurality of power generating units may comprise at least one open cycle gas turbine or at least one linear 15 power generator. In one embodiment of the invention, the electrical power generator is in electrical communication with at least one electrical battery unit. In another embodiment of the invention, the 20 controller is configured to balance the distribution of electrical power from electrical power generator against that provided by the at least one electrical battery unit. A second aspect of the invention provides for a process for operating an electrified cracker (e-cracker) 25 furnace, wherein the process comprises energy management system as defined herein. Suitably, the e-cracker furnace is selected from: a bio-oil cracker; a naphtha cracker; or an ethane cracker. Within the scope of this application, it is 30 expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and / or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and / or features of any embodiment can be combined in any way and / or combination, unless such features are incompatible. 5 Brief Description of the Drawings Figure 1 shows schematic of a process line up according to one embodiment of the present invention. 10 Detailed Description of the Invention All references cited herein are incorporated by reference in their entirety. Unless otherwise defined, all technical and scientific terms used herein have the same 15 meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Prior to setting forth the invention, a number of definitions are provided that will assist in the understanding of the invention. 20 As used herein, the term ‘comprising’ means any of the recited elements are necessarily included and other elements may optionally be included as well. ‘Consisting essentially of’ means any recited elements are necessarily included, elements that would materially affect the basic 25 and novel characteristics of the listed elements are excluded, and other elements may optionally be included. ‘Consisting of’ means that all elements other than those listed are excluded. Embodiments defined by each of these terms are within the scope of this invention. 30 The term ‘reactor’ as used herein is understood to comprise any industrial reactor suitable for industrial scale reactions and process heating, and, accordingly, the term reactor tube is understood to comprise any vessel in the form of a tube in which (a) substance(s) is (are) heated to high temperature. Likewise, the term ‘furnace’ is used to refer to a high- temperature enclosure, such as a reactor, designed for the thermal cracking of a hydrocarbon feedstock. 5 The terms ‘feed’, ‘feedstock’ or ‘feedstream’ should be considered as synonymous. These terms relate to at least one input material or substance that is introduced into a reactor and which is destined for chemical conversion into at least one output effluent of the 10 reactor either in the form of a reaction product that contributes to the yield, or as a byproduct such as a waste stream. The waste stream may comprise gaseous components collectively referred to as ‘tail gas’ or ‘off gas’. 15 As used herein, the term ‘renewable energy source’ generally refers to one or more technologies that utilize replenishable energy sources such as energy from water, wind, the sun, geothermal sources, and biomass sources such as energy crops. Such renewable energy sources may 20 include without limitation, a wind generator, a solar panel array, solar panel strings, wind turbines, hydroelectric power stations that utilize hydroelectricity and hydropower, solar panels (including solar photovoltaic technology, solar thermal collectors, solar assisted heat 25 pumps and / or solar concentrator technologies), solar arrays (e.g. arrays of solar panels), cogeneration plants that utilize biomass materials, biofuels, biodiesels, geothermal energy, and a combination thereof. Renewable electrons (e-) are, thus, components of an electricity 30 supply that is derived from a renewable energy source. Typically, an electricity supply will be derived from an electrical grid. As used herein the term ‘electrical grid’ or ‘grid supply’ relates to a system for distributing electrical power. As an integrated network, the electricity grid power system comprises a plurality of interconnected components, including but not limited to generators, transformers, transmission lines, and distribution networks. The primary objective of the 5 electricity grid power system is to facilitate the efficient and reliable transmission of electric energy, especially that produced from renewable sources, to end- use applications of the type described herein. Suitably, power grid management may include the capacity for 10 bidirectional power flow, real-time monitoring and various other control mechanisms. The chemicals industry is reliant upon the use of olefins as one of the most versatile building blocks for a 15 variety of petrochemical products such as solvents, polymers, resins, coatings and fibers. Traditionally the most effective way to produce light olefins is via thermal cracking of hydrocarbon feedstocks (the raw material) derived from crude oil or from natural gas. Steam cracking 20 is one such process that is a favoured process route. The steam cracker is often considered as the heart of the olefin process plant, particularly when used in the production of ethylene. The cracker unit has a very high energy consumption since cracking reactions are highly 25 endothermic. Depending on the type of cracker process, the feedstock hydrocarbons may be obtained from biomass sources (e.g. tall oil), naphtha or paraffins (e.g. ethane). Although the feedstock preference may differ per 30 region (i.e., naphtha in Europe and Asia, ethane in North America and the Middle East), the e-cracker operations are broadly similar. When using feedstocks that contain high levels of ethane, operating at high temperatures and low pressures, the feed undergoes dehydrogenation to form ethylene and hydrogen primarily. Other products may include methane, acetylene, propylene, propane and butadiene. The range of products are obtained as result of complex combination of 5 free radical mechanisms. As mentioned, the net effect of these reactions is endothermic, hence, in order to increase yield of the most desired end product of ethylene, external energy has to be supplied to maintain the temperature of the furnace. 10 Traditionally, the requirement for external energy for the cracker furnace would have been met entirely by combustion of methane or hydrogen containing tail / off gases produced as byproducts of various petrochemical refinery processes including the aforementioned cracking 15 reaction. In some instances, tail gases would be supplemented with additional natural gas – i.e. fuel gas. However, there has been an increasing trend to reduce the production of carbon dioxide from combustion of tail / off gases. This is accomplished by supply of thermal energy to 20 the cracker unit via use of resistive radiative heating technologies using an electricity supply (e-) derived from renewable sources – a so-called e-cracker. However, this trend results in an accumulation of tail / off gases which are no longer required for combustion and are utilised as 25 an additional product stream within other process flows of the refinery. In accordance with one embodiment of the present invention, a combustible tail gas originates from a hydrocarbon cracking reaction, typically an ethane 30 cracker, more suitably an ethane e-cracker at least partially operable on the basis of a renewable electricity supply. The tail gas may be utilised intermittently as source of fuel for a rapid ramp up / ramp down power generation system in cases where renewable grid supply falls below a predefined threshold that is necessary to ensure the steady state operation of the e-cracker. The determination of a threshold may be defined as an actual or anticipated reduction in available supply 5 from grid, or local generator capacity, below a predefined level required for continuous operation of an electrified cracker (e-cracker) furnace. The threshold may be selected from below 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20% or 10% of the electrical power required for continuous operation 10 of an electrified cracker (e-cracker) furnace. A conventional electrical power supply system may use both centralized and decentralized control with a focus on monitoring supply via transmission systems. Conventional electrical power systems typically rely on 15 centralized power generation, unidirectional power flow, and passive electricity distribution. However, with the integration of renewables, power distribution has shifted from the conventional paradigm to a new one with distributed power generation, bidirectional power flow, 20 and active electricity distribution. In embodiments of the invention, monitoring of the stability of the available supply from grid, or local generator capacity, may comprise monitoring of the ability of a high voltage power supply to maintain a steady frequency following an event 25 that results in a significant imbalance between generation and load. In further embodiments of the invention, monitoring of the stability of the available supply from grid, or local generator capacity, may comprise monitoring of the ability of a high voltage power supply to maintain 30 a steady voltage close to a nominal value at all buses in the distribution network after being subjected to a disturbance. Hence, monitoring of stability of supply may be seen as a load-oriented issue that depends, in part, upon an ability to maintain or restore equilibrium between the load demand of the e-cracker furnace and the power supply that is transferred from generators via the supply network. One contributing factor in voltage instability is that the loads tend to restore their power consumption 5 after a disturbance event to levels that may be beyond the transfer capability of the power network to accommodate. As such, thresholds may comprise a frequency threshold and / or a voltage threshold below which it is anticipated that stability of supply will be interrupted or reduced 10 sufficiently to require implementation of the energy management systems as described herein. A steam cracking ethylene production plant is typically composed of three main sections: pyrolysis (i.e., the cracker furnace and reactor), compression, and 15 product separation. The pyrolysis section of the conventional ethylene production plant consists of the cracker furnace, where feedstock hydrocarbons are cracked into smaller molecules, resulting in the formation of light olefins such as ethylene. At the outlet of the 20 cracking furnace, the heat in the hot gas mixture effluent is recovered in the transfer-line exchangers to produce high-pressure (HP) steam, which is then fed into the furnace and superheated. After heat recovery, the cracked effluent gas may be further cooled by contact with cooling 25 oil in an oil quench tower. In a gasoline fractionator, the heavy fraction of the resulting mixture is condensed, cooled, and recycled to the oil quench tower. Effluent gas may then be cleaned with scrubbers and strippers to remove pollutants such as sulphur. The cooled and cleaned gas 30 mixture is typically compressed in a steam turbine-driven compressor, which usually consists of several stages with intercooling. After compression, the gas mixture is dried and routed to a separation section. The separation section utilizes distillation, refrigeration, and extraction to separate products. Initial separation involves segregating methane and / or hydrogen components from other products to produce a methane-rich and / or hydrogen rich stream that is typically referred to as combustible tail gas. This tail 5 gas may be utilised as a product stream for other downstream processes. However, according to an embodiment of the invention it may also be used intermittently as source of fuel for a rapid deployment (e.g. rapid ramp up / ramp down) power generation system. A significant 10 advantage of the presently described embodiment is that utilisation of the by-product combustible tail gas for power generation does not diminish the primary product yield of the e-cracker which is light olefins, such as ethylene. In this way, ideal steady state operation may be 15 maintained with limited impact on product yield. Detailed Description of the Drawings Figure 1 shows a process line up according to a first embodiment of the invention. A hydrocarbon feed (HC) 20 is provided to a cracker unit. The HC feed may comprise a range of hydrocarbons typically utilised for cracking, including light paraffins such as ethane, propane and butane; or heavier feedstocks such as naphtha or a bio derived oil (e.g., tall oil or tallow). In a specific 25 embodiment the HC comprises a substantial proportion of ethane which is utilised for the formation of lower olefins such as ethylene. The e-cracker typically comprises a furnace that defines a cracking zone. Additional feeds comprise high pressure (HP) steam. The 30 reactor is surrounded by an electrical resistive heating means, suitably in the form of a radiative cladding layer. The electrical heater is predominantly supplied with electricity generated from renewable sources (identified in Figure 1 as Renewable e-) suitably from the grid supply or from local, so-called ‘behind the meter’ renewable generation technologies (e.g. on-site wind turbines or solar). The grid supply may be subject to intermittent fluctuations in available power, and / or in unit pricing, 5 due to the nature of renewable sources as described in more detail above. The reactor effluent from the cracker unit includes lower olefins, such as ethylene, as the reaction product. Byproduct combustible tail gas is another effluent stream 10 that is separated out from the mixture of effluent products that leave the e-cracker furnace (see description above). The combustible tail gas may comprise a methane as a majority component (e.g. greater than 50%m). The combustible tail gas may comprise a proportion of 15 hydrogen. Combustible tail gas is provided to a tail gas distribution system which is in under the control of an energy management system. In accordance with an embodiment of the present 20 invention, the tail gas is comprised within a feed for a power generator unit. Tail gas distribution system may divert tail gas to be utilised as a product stream (via a product unit) or it may be diverted for use as a fuel by the power generator unit. The utilisation of tail gas for 25 power generation or as product is subject to an energy management system. The energy management system comprises at least one controller that is configured to monitor electrical supply from the grid or local generation technologies as well as the power demands of the e-cracker 30 and associated processes. The energy management system comprises several key components that are capable of performing automated tasks including real-time monitoring and data acquisition tools to track energy usage across the process; and one or more smart sensors to collect data on power consumption, providing granular insights into energy patterns. Additionally, the energy management system may comprise a central processing unit (CPU) that allows for the remote monitoring and adjustment of power 5 management, as well as controlling the intermittent diversion of tail gas from a product stream to the power generation unit. Diversion of the tail gas to / from the power generation unit may be achieved using actuated valves within feed lines that are under direct control of 10 the energy management system. In embodiments of the invention the energy management system may include a computer system. The computer system can be configured for engineering compliant communications. The system can comprise one or15 more processors and one or more non-transient computer- readable storage media. The computer readable storage media can have stored thereon computer-executable instructions that are executable by the one or more processors to cause the computer system to perform the 20 methods and procedures described herein. Hence, it will be appreciated that the present invention may be a system, an apparatus, a method, and / or a computer program product. The computer program product may include a computer readable storage medium (or media) having computer 25 readable program instructions thereon for causing a processor to carry out aspects and embodiments of the present invention. The computer readable storage medium can be a tangible device that can retain and store instructions for 30 use by an instruction execution device, such as the controller within the energy management system. The computer readable storage medium may be, for example, but is not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. A non-exhaustive list of more specific examples of the computer readable storage medium includes the following: a 5 portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disk 10 (DVD), a memory stick, a floppy disk, a mechanically encoded device such as punch-cards or raised structures in a groove having instructions recorded thereon, and any suitable combination of the foregoing. Computer readable storage media may be accessible within a local area 15 network in the form of one or more linked servers or located remotely in cloud based virtual machines or servers. Cloud based services may be accessed via wired or wireless (wi-fi) telecommunications, such as over the internet. A computer readable storage medium, as used 20 herein, is not to be construed as being transitory signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through a waveguide or other transmission media (e.g., light pulses passing through a fiber-optic cable), or 25 electrical signals transmitted through a wire. In a specific embodiment of the invention the energy management system may be configured to undertake advanced analytics by utilising software modules to analyze data collected relating to electricity supply (e.g. from the 30 grid or local generator technologies), electricity unit pricing, electricity supply frequency, electricity supply voltage (e.g. within buses, interconnectors and / or power lines), and to anticipate or predict periods of fluctuation in the supply. According to embodiments of the invention, a machine learning (ML), or other artificial intelligence-based approach may be employed to generate algorithms, models, simulations and / or rules that are capable of performing an evaluation of data relating 5 supply and / or power demand within the e-cracker process. Methods for monitoring power network supply and stability are known to the skilled person (see, for example Liu et al. Annu. Rev. Control Robot. Auton. Syst. 2022.5:689– 716). 10 In a specific embodiment, a widely used class of machine learning algorithms involves simple linear models. Linear models are some of the most straightforward to use in machine learning approaches and make a prediction by using a linear function of the input features. Known 15 linear models may include linear regression, linear regression (ordinary least squares), ridge regression, Lasso and polynomial regression. In common with all linear regression models is the need to consider the given data points (the training data) and plot a best fit line to fit 20 the model in the best way possible and to thereby allow predictions to be made with a high level of accuracy. Regression techniques, such as those described above and that are more widely known in the art, may be used to generate a range of in silico rules and models based upon 25 training data sets comprising multiple metric values. Linear regression models are particularly useful for extrapolation, where there is a need to estimate values beyond the observational range provided within a training data set. 30 In an alternative embodiment of the invention, the machine learning models utilise a neural network approach. A neural network is a model containing an interconnected group of processing elements or "neurons" that process information using a connectionist approach to computation. Neural networks are often used to model complex relationships between inputs and outputs or to find patterns within data. Typically, neural networks process data in a non-linear, distributed, parallel fashion. Often 5 a neural network is an adaptive system that changes its structure during a learning phase. Functions are performed collectively and in parallel by the processing elements, rather than there being a clear delineation of subtasks to which various units are assigned. Generally, a neural 10 network involves a network of simple processing elements that exhibit complex global behaviour determined by the connections between the processing elements and element parameters. Neural networks may be used with algorithms designed to alter the strength of the connections in the 15 network to produce a desired signal flow. The strength, also known as a weighting, is altered during the training or learning phase. A further embodiment of the invention provides for the use of decision tree algorithms in the creation of in 20 silico models and rules. In particular, a random forest approach comprises a supervised machine learning algorithm that is constructed from decision tree algorithms. This algorithm is suitably used to predict behaviour and outcomes in a given set of circumstances. The term ‘random 25 forest’ refers to the use of a combination of classification tree predictors such that each tree depends on the values of a random vector sampled independently and with the same distribution for all trees in the so-called ‘forest’. A random forest is a learning ensemble 30 consisting of a bagging of un-pruned decision tree learners with a randomized selection of features at each split of the decision tree. Where ‘bagging’ is an ensemble meta-algorithm that improves the accuracy of the machine learning algorithm. A random forest grows a large number of classification trees, each of which votes for the most popular class. The random forest algorithm establishes the prediction outcome based on the predictions of the decision trees. It predicts by taking the average or mean 5 of the output from various trees in the forest. Increasing the number of trees in the forest, thus, increases the predictive power of the algorithm. Random forest algorithms are useful for predictive accuracy within a rich dataset (such as historical trends in grid power 10 supply) and are suitable for both regression and classification tasks. In addition to the above approaches, the process of in silico algorithm and rule generation may be enhanced by adoption of an automated machine learning approach 15 (autoML). AutoML is the process of automating the process of applying machine learning to real-world problems, such as optimizing the usage of tail gas as fuel to ramp up power supply in anticipation of a fluctuation in grid power. AutoML has been used as an artificial intelligence- 20 based solution to the ever-growing challenge of applying machine learning. An advantage of the high degree of automation in autoML is that it can allow non-experts to make use of machine learning models and techniques. Typically, during model training, autoML can create a 25 number of parallel pipelines that try different algorithms (such as any of the approaches described above) and parameters, thus, iterating through ML algorithms paired with feature selections. Each iteration produces a model with an associated training score. The better the training 30 score for the metric that is to be optimized for, the better the model is considered to ‘fit’ the data. Accordingly, the energy management system may operate in a so-called ‘Smart Mode’ using ML in order to anticipate and respond rapidly to fluctuations in supply, and / or electricity unit pricing and therefore maintain steady state operation of the e-cracker process. This is in direct contrast to systems operating under demand side management (DSM) limitations which actively seek to ramp 5 down the operation of the e-cracker to minimise power demand at times when grid supply is reduced. The power generation unit may comprise one or more power generation modules, such as comprised within an array. This has the advantage of enabling capacity to be 10 scaled up progressively according to need. In one embodiment of the invention the power generation modules may be comprised of a plurality of linear power generators and / or open cycle gas turbines. Linear power generators and open cycle gas turbines offer 15 distinct advantages for the rapid ramp-up of power generation. Linear power generators, such as free-piston engines or linear alternators, are known for their quick start-up times and high responsiveness to changes in power demand. These systems can efficiently convert fuel, such 20 as combustible tail gas, into electricity through linear motion, allowing for fast response times and effective load-following capabilities. On the other hand, open cycle gas turbines excel in rapid power generation due to their simple design and ability to reach full operating capacity 25 swiftly. The combustion process in gas turbines enables rapid acceleration, making them well-suited for applications where immediate power output is crucial. Both linear power generators and open cycle gas turbines provide flexibility in adjusting output levels, making 30 them valuable assets where the demand for electricity fluctuates rapidly and during sudden load changes. Their agility in responding to varying power requirements contributes to a more responsive and reliable power generation infrastructure within the power generation unit. The power generation unit may also be supplemented by electricity from battery storage. The excess, low cost 5 electricity may be routed to battery capacity when supply exceeds demand. Alternatively, battery storage can be used to cover short periods of ramp up when there is a sudden interruption in grid supply. Alternatively, battery storage may be used to store excess electricity generated 10 by the power generation unit during ramp down. Hence, battery capacity may be utilised by the energy management system to smooth out the fluctuations in periods between switching from grid supply to full or partial reliance on the power generation unit to maintain steady state 15 operation. In an embodiment of the invention the power generator unit is capable of supplying substantially all of the required electrical power requirement of the e- cracker furnace and associated downstream processes for a 20 period of time. The period of time may be as little as a few minutes, to one hour, 24 hours, 48 hours, one week, one month or longer. In another embodiment of the invention the electrical power unit is capable of supplying up to 50% of 25 the required electrical power requirement of the e-cracker furnace and associated downstream processes indefinitely. Typically, the electrical power unit is capable of supplying up to 40%, optionally up to 30%, and typically not less than 20% of the required electrical power 30 requirement of the e-cracker furnace and associated downstream processes indefinitely. Although particular embodiments of the invention have been disclosed herein in detail, this has been done by way of example and for the purposes of illustration. The aforementioned embodiments are not intended to be limiting with respect to the scope of the appended claims, which follow. It is contemplated by the inventors that various substitutions, alterations, and modifications may 5 be made to the invention without departing from the spirit and scope of the invention as defined by the claims.

Claims

SP3095 - 22 - C L A I M S 1. An energy management system for use with an electrified cracker (e-cracker) furnace, the system comprising: a feed comprised of a combustible tail gas obtained 5 from an e-cracker furnace; a controller that monitors a supply of electrical power to an e-cracker and also controls the feed; and an electrical power generator that is configured to utilise the combustible tail gas as a source of fuel and 10 is in gaseous communication with the feed; wherein the controller is configured to detect or anticipate a deficit in the supply of electrical power to the e-cracker below a threshold level and when a deficit is detected or anticipated to supply the combustible tail 15 gas to the electrical power generator in order to generate sufficient electrical power to compensate for the deficit in the supply of electrical power.

2. The system of claim 1, wherein the supply of 20 electrical power comprises a proportion of electrical power derived from renewable sources.

3. The system of claim 1, wherein the e-cracker furnace is selected from: a bio-oil cracker; a naphtha cracker; or 25 an ethane cracker.

4. The system of claim 1, wherein the controller is configured to divert the feed to a product stream if the supply of electrical power to the e-cracker furnace rises 30 above the threshold level.

5. The system of claim 1, wherein the electrical power generator is able to supply substantially all of the required electrical power requirement of the e-cracker furnace for a period of time. 5 6. The system of claim 1, wherein the electrical power generator is able to supply up to 50% of the required electrical power requirement of the e-cracker furnace indefinitely. 10 7. The system of claim 1, wherein the electrical power generator is comprised of an array of modular power generating units. 15 8. The system of claim 7, wherein the array of modular power generating units may be comprised of a plurality of rapid ramp up / ramp down generators.

9. The system of claim 7, wherein, the plurality of 20 power generating units may comprise at least one open cycle gas turbine or at least one linear power generator.

10. The system of claim 1, wherein the electrical power generator is in electrical communication with at least one 25 electrical battery storage unit.

11. The system of claim 10, wherein the controller is configured to balance the distribution of electrical power from an electrical power generator with that provided by 30 the at least one electrical battery unit.

12. The system of claim 1, wherein the combustible tail gas comprises methane.

13. The system of claim 1, wherein the combustible tail gas comprises hydrogen.

14. A process for operating an electrified cracker (e- 5 cracker) furnace, wherein the process comprises energy management system as defined in claim 1.

15. The process of claim 14, wherein the e-cracker furnace is selected from: a bio-oil cracker; a naphtha 10 cracker; or an ethane cracker.