Insight into the Sustainable Integration of Bio- and Petroleum Refineries for the Production of Fuels and Chemicals.

A petroleum refinery heavily depends on crude oil as its main feedstock to produce liquid fuels and chemicals. In the long term, this unyielding dependency is threatened by the depletion of the crude oil reserve. However, in the short term, its price highly fluctuates due to various factors, such as regional and global security instability causing additional complexity on refinery production planning. The petroleum refining industries are also drawing criticism and pressure due to their direct and indirect impacts on the environment. The exhaust gas emission of automobiles apart from the industrial and power plant emission has been viewed as the cause of global warming. In this sense, there is a need for a feasible, sustainable, and environmentally friendly generation process of fuels and chemicals. The attention turns to the utilization of biomass as a potential feedstock to produce substitutes for petroleum-derived fuels and building blocks for biochemicals. Biomass is abundant and currently is still low in utilization. The biorefinery, a facility to convert biomass into biofuels and biochemicals, is still lacking in competitiveness to a petroleum refinery. An attractive solution that addresses both is by the integration of bio- and petroleum refineries. In this context, the right decision making in the process selection and technologies can lower the investment and operational costs and assure optimum yield. Process optimization based on mathematical programming has been extensively used to conduct techno-economic and sustainability analysis for bio-, petroleum, and the integration of both refineries. This paper provides insights into the context of crude oil and biomass as potential refinery feedstocks. The current optimization status of either bio- or petroleum refineries and their integration is reviewed with the focus on the methods to solve the multi-objective optimization problems. Internal and external uncertain parameters are important aspects in process optimization. The nature of these uncertain parameters and their representation methods in process optimization are also discussed

Opportunities for Dutch Biorefineries

Deze Roadmap Bioraffinage beschrijft een aantal mogelijke routes naar de ontwikkeling en implementatie van een bioraffinage-gerelateerde Bio-based Economy in Nederland. De Roadmap combineert korte- en middellange termijn mogelijkheden (commerciële implementatie, demonstratie plants, pilot plants en gerelateerd toegepast onderzoek) met strategisch onderzoek voor de langere termijn. Tevens zijn vier z.g. Moonshots uitgewerkt, als voorziene bioraffinagestrategieën met een grote potentie voor de Nederlandse economi

Modelling framework for the design of hydrogen-CCS networks to decarbonise heating and industrial clusters

This dissertation elucidates the value of H₂ and CO₂ infrastructure in decarbonising “difficult-to-abate” sectors of the economy. We analyse infrastructure for low-carbon fuels and energy vectors at different scales, and present a flexible formulation to integrate relevant technologies for their interconversion. We use a mixed integer linear programming (MILP) approach to formulate spatial systems optimisation problems, and identify solutions that can accelerate the transition to low-carbon systems. The modelling framework can incorporate spatial and temporal granularity, whilst also capturing the nuances of a site, country, or an industrial cluster. Through its application, we outline a transition pathway for the natural-gas based heating sector to H₂ in Great Britain, noting the key barriers to cost-effective deployment. The cost-optimal supply mix contains natural gas reforming with CCS, flexible electrolytic H₂ production, large volumes of salt cavern storage, and biomass gasification with CCS to offset any remaining methane and CO₂ emissions from the natural gas supply chain, and the production plants. Given the uncertainties involved, we note that a complete conversion of the gas grid in the UK to H₂ for heating buildings is unlikely to be viable. We find that a portfolio-based approach containing post-combustion CO₂ capture, fuel switching with H₂, and negative emissions is a cost-effective strategy to decarbonise industrial clusters in the UK. This achieves greater decarbonisation and avoids an overreliance on CO₂ emission offsets. The total costs of CO₂ avoidance can be reduced by using existing fuels such as refinery fuel gases for H₂ production. Natural gas plays an important role as fuel and feedstock for post-combustion and methane reforming, and is the primary determinant of the total costs of the system. This has implications for the security of supply, given that countries such as the UK import as much natural gas as they produce domestically. A cradle-to-gate lifecycle assessment of reforming, and electrolytic H₂ production using grid power and offshore wind power, shows that the lowest global warming potential is generated using a dedicated renewable-led supply. However, none of the production pathways are dominant across all key environmental performance indicators. This indicates the potential for “problem shifting” to occur by solely focussing on a given pathway for long-term supply development. We note that the environmental performance of H₂ improves with reductions in upstream methane emissions, and an increase in the capacity factor of renewable power generation assets.Open Acces

Operational Risk Assessment of Routing Flare Gas to Boiler for Cogeneration

Flaring is a controlled combustion process in which unwanted or excess hydrocarbon gases are released to flare stack for disposal. Flaring has a significant impact on environment, energy and economy. Flare gas integration to cogeneration plant is an alternative to mitigate flaring, benefiting from utilizing waste flare gas as a supplemental fuel to boilers and or gas turbines. Earlier studies have shown the energy and economic sustainability through integration. However, the impact of flare gas quality on cogeneration plants are yet to be identified. This paper studies the effect of flare gas composition and temperature from an ethylene plant to an existing boiler during abnormal flaring. The study proposes a unique framework which identifies the process hazards associated with variation in fuel conditions through process simulation and sensitivity analysis. Then, a systematic approach is used to evaluate the critical operational event occurrences and their impacts through scenario development and quantitative risk assessment, comparing a base case natural gas fuel with a variable flare gas fuel. An important outcome from this study is the identification of critical fuel stream parameters affecting the fired boiler operation through process simulation. Flare stream temperature and presence of higher molecular weight hydrocarbons in flare streams showed minimal effect on boiler condition. However, hydrogen content and rich fuel-air ratio in the boiler can affect the boiler operating conditions. Increase in the hydrogen content in flare to fuel system can increase the risk contour of cogeneration plant, affecting the boiler gas temperature, combustion mixture and flame stability inside the firebox. Quantitative risk analysis through Bayesian Network showed a significant risk escalation. With 12 hours of flare gas frequency per year, there is a substantial rise in the probability of occurrence of boiler gas temperature exceeding design limit and rich fuel mixture in the firebox due to medium and high hydrogen content gas in flare. The influence of these events on flame impingement and tube rupture incidents are noteworthy for high hydrogen content gas. The study also observed reduction in operational time as the hydrogen content in flare gas is increased from low to high. Finally, to operate fire tube steam boiler with flare gas containing higher amount of hydrogen, the existing cogeneration system needs to update its preventive safeguards to reduce the probability of loss control event

Operational Risk Assessment of Routing Flare Gas to Boiler for Cogeneration

Flaring is a controlled combustion process in which unwanted or excess hydrocarbon gases are released to flare stack for disposal. Flaring has a significant impact on environment, energy and economy. Flare gas integration to cogeneration plant is an alternative to mitigate flaring, benefiting from utilizing waste flare gas as a supplemental fuel to boilers and or gas turbines. Earlier studies have shown the energy and economic sustainability through integration. However, the impact of flare gas quality on cogeneration plants are yet to be identified. This paper studies the effect of flare gas composition and temperature from an ethylene plant to an existing boiler during abnormal flaring. The study proposes a unique framework which identifies the process hazards associated with variation in fuel conditions through process simulation and sensitivity analysis. Then, a systematic approach is used to evaluate the critical operational event occurrences and their impacts through scenario development and quantitative risk assessment, comparing a base case natural gas fuel with a variable flare gas fuel. An important outcome from this study is the identification of critical fuel stream parameters affecting the fired boiler operation through process simulation. Flare stream temperature and presence of higher molecular weight hydrocarbons in flare streams showed minimal effect on boiler condition. However, hydrogen content and rich fuel-air ratio in the boiler can affect the boiler operating conditions. Increase in the hydrogen content in flare to fuel system can increase the risk contour of cogeneration plant, affecting the boiler gas temperature, combustion mixture and flame stability inside the firebox. Quantitative risk analysis through Bayesian Network showed a significant risk escalation. With 12 hours of flare gas frequency per year, there is a substantial rise in the probability of occurrence of boiler gas temperature exceeding design limit and rich fuel mixture in the firebox due to medium and high hydrogen content gas in flare. The influence of these events on flame impingement and tube rupture incidents are noteworthy for high hydrogen content gas. The study also observed reduction in operational time as the hydrogen content in flare gas is increased from low to high. Finally, to operate fire tube steam boiler with flare gas containing higher amount of hydrogen, the existing cogeneration system needs to update its preventive safeguards to reduce the probability of loss control event

Multistage Infrastructure System Design: An Integrated Biofuel Supply Chain against Feedstock Seasonality and Uncertainty

A biofuel supply chain consists of various interdependent components from feedstock resources all the way to energy demand sites. This study focuses on the design of an efficient biofuel supply chain system against seasonal variations and uncertainties of feedstock supply in an integrative manner. By integrating planning and operational decisions in a stochastic programming framework, we aim at finding an effective design strategy for biofuel supply chain that is economically viable and hedges well against a wide range of future uncertainties. A solution algorithm based on scenario decomposition is designed to overcome computational challenges involved in large-scale applications. A California case study is implemented to demonstrate the applicability of the proposed methods in evaluating the economic potential, the infrastructure needs, and the risk of wastes-based bioethanol production

Renewable hydrogen supply chains: A planning matrix and an agenda for future research

Worldwide, energy systems are experiencing a transition to more sustainable systems. According to the Hydrogen Roadmap Europe (FCH EU, 2019), hydrogen will play an important role in future energy systems due to its ability to support sustainability goals and will account for approximately 13% of the total energy mix in the coming future. Correct hydrogen supply chain (HSC) planning is therefore vital to enable a sustainable transition, in particular when hydrogen is produced by water electrolysis using electricity from renewable sources (renewable hydrogen). However, due to the operational characteristics of the renewable HSC, its planning is complicated. Renewable hydrogen supply can be diverse: Hydrogen can be produced de-centrally with renewables, such as wind and solar energy, or centrally by using electricity generated from a hydro power plant with a large volume. Similarly, demand for hydrogen can also be diverse, with many new applications, such as fuels for fuel cell electrical vehicles and electricity generation, feedstocks in industrial processes, and heating for buildings. The HSC consists of various stages (production, storage, distribution, and applications) in different forms, with strong interdependencies, which further increase HSC complexity. Finally, planning of an HSC depends on the status of hydrogen adoption and market development, and on how mature technologies are, and both factors are characterised by high uncertainties. Directly adapting the traditional approaches of supply chain (SC) planning for HSCs is insufficient. Therefore, in this study we develop a planning matrix with related planning tasks, leveraging a systematic literature review to cope with the characteristics of HSCs. We focus only on renewable hydrogen due to its relevance to the future low-carbon economy. Furthermore, we outline an agenda for future research, from the supply chain management perspective, in order to support renewable HSC development, considering the different phases of renewable HSCs adoption and market development