8 research outputs found
Engineering design of localised synergistic production systems.
Addressing a number of critical challenges caused by centralised production and large scale distribution infrastructures, local production systems designed in a synergistic manner could offer a possible pathway towards sustainability. The thesis focuses on the technical design of local production systems integrating local heterogeneous processes to satisfy local demands through efficient use of locally available renewable resources within technical and ecological constraints. A conceptual and quantitative multi-level framework, based on the Cumulative Exergy Resource Accounting methodology, was first developed for a better understanding of a local production system by considering the production and consumption of products or services as well as ecological processes. A general design framework comprising an optional preliminary design stage followed by a simultaneous design stage based on mathematical optimisation was then developed for solving the design problem towards minimum overall resource consumption. The preliminary design stage considers each supply subsystem individually and allows insights into the potential interactions between them. The simultaneous design stage has the capacity to include all design integration possibilities. A second, insight-based approach was further developed, which offers a new hierarchical and iterative decision and analysis procedure and incorporates design principles and ability to examine design decisions. The multilevel resource accounting framework was demonstrated on ethanol production from cane and successfully revealed how decisions at one level would affect other levels of the system. Both design approaches were illustrated on a case study for the design of local food-energy-water nexus. It showed the advantages of an integrated design of a system which makes use of local resources to meet its demands over a system relying on centralised supplies and over a design without considering integration opportunities between subsystems. The insight-based approach was also found to produce a comparable design to the simultaneous design approach while offering more valuable insights for decision makers
Designing integrated local production systems:a study on the food-energy-water nexus
Centralised production of essential products and services based on fossil fuels and large scale distribution infrastructures has contributed to a plethora of issues such as deterioration of ecosystems, social-economic injustice and depletion of resources. The establishment of local production systems that deliver various products for local consumption (e.g. food, energy and water) by making the best use of locally available renewable resources can potentially alleviate unsustainable resource consumption. The main objective of this work is to develop process systems engineering tools combined with the concept of resource accounting using exergy for the design of such local production systems. A general design framework comprising an optional preliminary design stage followed by a simultaneous design stage based on mathematical optimisation is proposed. The preliminary design stage considers each supply subsystem individually and allows insights into the potential interactions between them. The simultaneous design stage yields an optimal design of the local production system and has the capacity to include all design integration possibilities between the subsystems and generate a truly integrated design solution. The proposed methodology, which reflects generalised principles for designing local production systems, has been illustrated through a case study on the integrated design of the food-energy-water nexus for a designated eco-town in UK. It demonstrates the advantages of an integrated design of a system making use of local resources to meet its demands over a system relying on centralised supplies and a design without considering integration opportunities between subsystems
Designing integrated local production systems:a study on the food-energy-water nexus
Centralised production of essential products and services based on fossil fuels and large scale distribution infrastructures has contributed to a plethora of issues such as deterioration of ecosystems, social-economic injustice and depletion of resources. The establishment of local production systems that deliver various products for local consumption (e.g. food, energy and water) by making the best use of locally available renewable resources can potentially alleviate unsustainable resource consumption. The main objective of this work is to develop process systems engineering tools combined with the concept of resource accounting using exergy for the design of such local production systems. A general design framework comprising an optional preliminary design stage followed by a simultaneous design stage based on mathematical optimisation is proposed. The preliminary design stage considers each supply subsystem individually and allows insights into the potential interactions between them. The simultaneous design stage yields an optimal design of the local production system and has the capacity to include all design integration possibilities between the subsystems and generate a truly integrated design solution. The proposed methodology, which reflects generalised principles for designing local production systems, has been illustrated through a case study on the integrated design of the food-energy-water nexus for a designated eco-town in UK. It demonstrates the advantages of an integrated design of a system making use of local resources to meet its demands over a system relying on centralised supplies and a design without considering integration opportunities between subsystems
A Framework for Modeling Local Production Systems with Techno-Ecological Interactions
At the local scale, interconnected production, consumption, waste management, and other man-made technological components interact with local ecosystem components to form a local production system. The purpose of this work is to develop a framework for the conceptual characterization and mathematical modeling of a local production system to support the assessment of process and component options that potentially create symbiosis between industry and ecosystem. This framework has been applied to a case study to assess options for the establishment of a local energy production system that involves a heathland ecosystem, bioenergy production, and wastewater treatment. We found that the framework is useful to analyze the two-way interactions between these components in order to obtain insight into the behavior and performance of the bioenergy production system. In particular, the framework enables exploring the levels of the ecosystem states that allow continuous provisioning of resources in order to establish a sustainable techno-ecological system
A Framework for Modeling Local Production Systems with Techno-Ecological Interactions
At the local scale, interconnected production, consumption, waste management, and other man-made technological components interact with local ecosystem components to form a local production system. The purpose of this work is to develop a framework for the conceptual characterization and mathematical modeling of a local production system to support the assessment of process and component options that potentially create symbiosis between industry and ecosystem. This framework has been applied to a case study to assess options for the establishment of a local energy production system that involves a heathland ecosystem, bioenergy production, and wastewater treatment. We found that the framework is useful to analyze the two-way interactions between these components in order to obtain insight into the behavior and performance of the bioenergy production system. In particular, the framework enables exploring the levels of the ecosystem states that allow continuous provisioning of resources in order to establish a sustainable techno-ecological system
Role of bioenergy, biorefinery and bioeconomy in sustainable development: strategic pathways for Malaysia
Malaysia has a plethora of biomass that can be utilized in a sustainable manner to produce bio-products for circular green economy. At the 15th Conference of Parties in Copenhagen, Malaysia stated to voluntarily reduce its emissions intensity of gross domestic product by upto 40% by 2020 from 2005 level. Natural resources e.g. forestry and agricultural resources will attribute in achieving these goals. This paper investigates optimum bio-based systems, such as bioenergy and biorefinery, and their prospects in sustainable development in Malaysia, while analyzing comparable cases globally. Palm oil industry will continue to play a major role in deriving products and contributing to gross national income in Malaysia. Based on the current processing capacity, one tonne of crude palm oil (CPO) production is associated with nine tonnes of biomass generation. Local businesses tend to focus on products with low-risk that enjoy subsidies, e.g. Feed-in-Tariff, such as bioenergy, biogas, etc. CPO biomass is utilized to produce biogas, pellets, dried long fibre and bio-fertilizer and recycle water. It is envisaged that co-production of bio-based products, food and pharmaceutical ingredients, fine, specialty and platform chemicals, polymers, alongside biofuel and bioenergy from biomass is possible to achieve overall sustainability by the replacement of fossil resources. Inception of process integration gives prominent innovative biorefinery configurations, an example demonstrated recently, via extraction of recyclable, metal, high value chemical (levulinic acid), fuel, electricity and bio-fertilizer from municipal solid waste or urban waste. Levulinic acid yield by only 5. wt% of waste feedstock gives 1.5 fold increase in profitability and eliminates the need for subsidies such as gate fees paid by local authority to waste processor. Unsustainable practices include consumable food wastage, end-of-pipe cleaning and linear economy that must be replaced by sustainable production and consumption, source segregation and process integration, and product longevity and circular economy