This thesis evaluates the environmental performance of Galactaric Acid (Gal-A) derived from sugar beet pulp (SBP), as a potential eco-friendlier alternative to Chromium(III) and Disodium EDTA in industrial applications. Utilizing a prospective lifecycle assessment, the study forecasts the environmental impacts of Gal-A’s use in the Netherlands by 2030, focusing on its application as a chelating agent (application 1) in shampoo formulations and as a surface coating for zinc-plated steel (application 2).
The data collection to produce Gal-A was conducted using a mass balanced bill of materials provided by Royal Cosun. A combination of literature data and stoichiometric calculations were utilized for other processes within the study. The literature offered insights into the design of value chains and process data, while stoichiometric calculations allowed for the detailed analysis of chemical reactions and compound formations.
The scaling of the Gal-A production foreground in the thesis is informed by input from process technologists at Royal Cosun, ensuring a realistic and industry-informed projection, with attention to the valorization of side streams and internal recycling flows. For the scaling of other processes, literature research plays a crucial role, particularly in understanding the restrictions on chemicals and the development of novel production processes.
The results indicated for application 1, that Gal-A as a chelating agent in shampoo formulations showed mixed results. While it demonstrated advantages in reducing toxicity impacts due to its biodegradability, it also presented trade-offs in eutrophication, soil use, and acidification. These trade-offs are linked to the agricultural origins of the sugar beet pulp and the enzymes used in Gal-A’s production.
The Gal-A-based anti-corrosive coating scored superiorly across all impact categories compared to traditional coatings. The use of Gal-A showed significant environmental benefits, particularly in reducing climate change impacts. However, uncertainties remain regarding the application procedure and the long-term performance of Gal-A as a coating, which necessitates further research.

The CO2 emissions started to peak during the start of this century and the steel manufacturing sector accounts for 25% of the global CO2 emissions. The majority of steel production is based on the route of the basic oxygen furnace (BOF) route, which is energy efficient. This production route results in the emission of BOF gas. So a new method to produce Isopropyl alcohol via BOF gas fermentation was developed for the pilot scale plant and the LCA was performed by Liew et al., (2022). The carbon-negative emissions were calculated and estimated in the pilot scale study. A few inconsistencies were identified in the calculation method, in which the components utilized for the production process contributed less than 5% to the Global Warming Potential value, and the replacements provided to the steel mill for the BOF gas redirection were cut off. The LCA value for the pilot-scale plant was incomplete and inconsistent, and only the GWP was chosen as the prominent midpoint indicator. Based on this pilot-scale plant, an industrial-scale (46 kton/ yr) base case process model was developed for the gas-fermentation process to produce IPA. The fermentation is the major step involved in the production of IPA, which involves the acetogenic bacteria Clostridium Autoethanogenum. The initial process involves the capture of the emission of BOF gas for compression and cooling performed because the temperature of BOF gas is around 1100°C. This compressed gas is fermented using of microbes and filtered out to obtain the filtered broth. Then the IPA is separated from the filtered broth using extractive distillation, using glycerol. The major product of IPA is processed out of the system. This research aims to analyze and estimate the environmental impacts of this process model of BOF gas fermentation to produce Isopropyl alcohol. The assessments were performed for the base case and the 11 process parameters of CO conversion, Volumetric mass transfer rate of CO, Product selectivity, Dilution rate, Extractive distillation glycerol mole fraction, Temperature offgas condenser, Anaerobic waste conversion, Extractive distillation molar reflux ratio, Biomass liq-liq mole fraction and the broth and glycerol purges. The impact assessment results help to identify the potential contributors in the process that affect the environment, so the process model can be optimized to yield lower impact values concerning the environmental perspectives.

The 7 midpoint indicators namely Global Warming Potential (GWP), Stratospheric Ozone Depletion (SOD), Fine Particulate Matter Formation (FPMF), Freshwater Eutrophication (FE), Marine Eutrophication (ME), Human Carcinogenic Toxicity (HCT), and Land Use (LU) were chosen to obtain a detailed view on the ecosystem, human health, and the environmental effects. The replacement calculations estimated for 1 kg of IPA production is 4.324 MJ of heat, and 0.877 kWh of electricity, has to be replaced for the steel mill. The impact assessment for the base case model was performed and compared with the conventional IPA production method (GWP: 2.026 kg CO2 eq.), the global warming potential for the BOF gas fermentation method (GWP: 27.656 kg CO2 eq.) estimated to be a 1265% increase compared with the conventional IPA method. Similarly, all seven impact categories are estimated to have a huge increase in values. An elaborate study compared and identified the most influential process parameters. The process parameter of dilution rate in which the dilution rate is lowered by 30% from the base case value appears to be the process parameter with a lower impact value of 20.464 kg CO2 eq. for the Global Warming Potential (26% lower than base case), 1.72E-05 kg CFC11 eq. for the Stratospheric Ozone Depletion (31% lower than base case), 9.618E-03 kg PM2.5 eq. for the Fine Particulate Matter Formation (38% lower than base case), for the Freshwater Eutrophication the value is 9.853E-04 kg P eq. (53% lower than base case), 5.531E-03 kg N eq. for Marine Eutrophication (33% lower than base case), 1.733E-01 kg 1,4-DCB for the Human Carcinogenic Toxicity (53% lower than base case), and the 3.265 m2a crop eq. (32% lower than base case) for the Land use impact categories. The major contributors are the high-pressure and low-pressure steam utility contributing greater than 56% for the impact category values of the GWP, FPMF, FE, and HCT particularly. The glycerol used for the extractive distillation process contributed greater than 92% for the impact categories of SOD, ME, and LU. The impact assessments across different indicators were interpreted and the major process parameters that are more influential in reducing the impact values are identified. The results indicate that the major contribution to the impact value is reduced by the emission credit ±40% for preventing the BOF gas from flaring. The carbon dioxide emission from the process, glycerol component, and steam utility collectively contribute majorly which account for more than 90% of the total impact values in the impact categories. Lowering the dilution rate, glycerol purge fraction, and glycerol mole fraction by -30%, and increasing the volumetric mass transfer rate by +30% of the process model could result in lower impact values. The CO2 emitted from the process is estimated to be 9.34 kg CO2 eq. This emission is higher than the feedstock (BOF gas) used for the gas-fermentation process. The entertainer glycerol is anaerobically digested and combusted leading to the 10% of the total CO2 emission of the process model. The process model should be updated with the process parameters listed above and a similar life cycle impact assessment has to be performed to compare the impact values. This updated process model might have comparatively better results. The sensitivity study has been performed to estimate the percentage effects of the combined glycerol and steam components on the midpoint indicator impact value. Cutting off the components of glycerol and steam from the process model still yields the GWP value of 6.16 kg CO2 eq. for industrial scale process which is a 204 % increase than the conventional IPA process. This implies that the updated process model with similar process steps cannot obtain impact values lower than the conventional IPA method. To lower the impact value of GWP, the CO2 emission from the process should be sequestrated (carbon capture) to lower the GWP value by 42% from the base case.

Hydrogen is an interesting and promising alternative for fuels. Currently, most hydrogen is produced via a process called steam reforming, where a reaction between methane and water occurs, with carbon monoxide and carbon dioxide as waste products and released in the atmosphere. This work presents a study on the sustainable production of hydrogen. A pool of six hydrogen processes were chosen; three based on electrolysis, two based on fermentation and one based on electrolysis combined with a microbial community. On these six methods an early stage analysis was applied, screening for economics, environmental impacts and processrelated costs and impacts. Two electrolysis methods were selected for a conceptual design; alkaline electrolysis (AE) and polymer electrolyte membrane (PEM) electrolysis, both for an annual production of 1 million kg hydrogen. The fixed capital was established $86.8M for AE and $62.3M for PEM. After the design, a techno-economic analysis was performed, providing the total production cost (TPC) and the minimum fuel selling price (MFSP). For the AE, the MFSP resulted in being $21.46/kg hydrogen and an TPC of $17.16/kg hydrogen. The biggest contribution to the MFSP was the depreciation, being $10.19/kg hydrogen. The PEM electrolysis had a MFSP of $17.56/kg hydrogen and an TPC of $14.05/kg hydrogen. Also for PEM electrolysis, the biggest contribution to the MFSP was the depreciation, which was $7.32/kg. A sensitivity analysis was performed and showed the biggest uncertainty in the equipment cost and the interest rate. The MFSP for AE changes ± $3.79/kg hydrogen by a change in equipment cost of 30% and ± $3.27 - $3.72 by a 5 percentage point change of the interest rate. The MFSP for PEM changes ± $2.73/kg hydrogen by a change in equipment cost of 30% and ± $2.36 - $2.73 by a 5 percentage point change of the interest rate. Based on the results from the techno-economic analysis and sensitivity analysis, PEM electrolysis was identified as the superior method.

Global water-related impacts are in constant aggravation due to climate change, increased water demand, intensive human activities, and deterioration of the quality of water bodies.
Under this paradigm, humanity must adapt and implement measures to ensure both the quality of water bodies and the sustainable management of resources.
As a result, unexploited water resources, such as wastewater, have been a focus of attention among researchers. Wastewater Treatment (WWT) technologies stand as an important step to promote water reuse and potentially recover raw materials with added value.
While WWT technologies have been assessed at the environmental and economic levels, their social repercussions are not extensively studied. Hence, the present master thesis project resorts to the Social Life Cycle Assessment (S-LCA) framework to execute an evaluation of the social performance of an innovative WWT system for resource recovery in Portugal. S-LCA was conducted at the organizational level, assessing the social performance of organizations in the value chain through the evaluation of the social effects on Workers, Consumers, Local Community, Society, and value chain actors. In addition, a generic assessment was performed to identify hotspot areas of the Portuguese water sector, following the S-LCA framework.
The systems under analysis integrate a Water Mining (WM) project case study, where an innovative urban WWT technology is implemented. In the two systems defined, the wastewater is treated with the Nereda technology and safely discharged into the environment. Nevertheless, while in the reference system the sludge generated from the treatment is stored or forwarded to landfill, in the novel system a new biobased raw material is recovered.
Regarding the generic assessment, a total of eleven impact subcategories were listed as critical areas regarding the operation of companies in the WWT sector. These were further investigated in the site-specific assessment conducted at the plant level. The results of the site-specific assessment indicate that the organisations included in the assessment performed well for both
systems under analysis. However, organizations’ individual performances reflect that improvements are necessary mainly in the subcategories “equal opportunities/discrimination” and “community engagement”. Other subcategories where organizations need to improve are “promoting social responsibility”, “social benefits/social security”, “local employment”, “health and safety of consumers”, “safe and healthy living conditions” and “public commitment to sustainability issues”. For each organization that did not reach a satisfactory performance
level in a certain subcategory, improvement recommendations were proposed.
In general, the novel system performs better in all impact subcategories when compared to the reference system. Nonetheless, this result is intrinsically connected to system characteristics and model decisions such as weighting factors definition and multifunctionality matters, which remain as rather abstract concepts that do not completely reflect reality.
The main challenges faced during the study concern the accessibility and availability of site-specific and generic data. In terms of site-specific assessment, the high similarity of the reference and novel systems in terms of organizations involved hindered the comparison of the two systems.
To conclude, the S-LCA methodology allowed the identification of social hotpots areas as well as the evaluation of the reference and novel systems' social performance, contributing to the elaboration of strategies to improve social sustainability along the value chain of innovative WWT technologies.

Water scarcity problems will continue to exacerbate in many parts of the world, urging society to mitigate or adapt. Consequently, unconventional water resources, such as municipal wastewater, are becoming more relevant. This thesis aims to measure and evaluate the social impacts of wastewater treatment (WWT) systems potentially stemming from the social performance of organizations and social risks in the value chain. Two WWT systems are studied: one is the current WWT facility operating in La Llagosta, Barcelona, Spain (reference system), and the other is one of the case studies of the Water Mining (WM) project (original system). The WM project aims to apply innovative approaches to recover clean water and other resources from municipal and industrial wastewater and seawater.
Social life cycle assessment (S-LCA) was applied to evaluate the social performances of organizations in a site-specific assessment and to assess the social risks along the systems’ value chains in a generic assessment through PSILCA. The results of the latter show that, in both systems, most risks occur in some subcategories from the “Workers”, “Local community”, “Society”, and “Value chain actors” stakeholder categories. The results of the former indicate that the organizations performed relatively well in both systems. However, improvements are needed in some subcategories. Moreover, after accounting for each organization’s share and allocating the results, the original system’s performance is better than the reference system in most subcategories. For each organization that did not achieve the acceptable level (Basic Requirement), suggestions for improvement are offered. Finally, although social performances could be linked to a product and multifunctionality could be solved, the results must be interpreted with caution in light of the limitations of S-LCA. Further research is needed for the assessment of the social implications of circular systems.

The European Union has set itself the target of becoming climate neutral by 2050 through a series of policies affecting industries such as the energy sector. This sector will be subject to considerable change with renewable energies set to replace fossil fuels. However, the EU will not be able to solely rely on its domestic production of renewable energies. An option would be to import from Africa as it is close to Europe, while it has considerable potential in terms of renewable energies. Therefore, this research addresses the following question: How can Africa-EU hydrogen and biomass supply chains contribute to the greening of the EU’s energy mix by 2050 while contributing to Africa’s renewable energy development? This question is answered by assessing two renewable energy supply chains: biomass and hydrogen. This study uses the Strength, Weaknesses, Opportunities and Threats (SWOT) analysis framework to investigate these intercontinental supply chains. The research identifies the top-three African countries based on parameters relevant to both supply chains, such as their existing energy infrastructure, transport infrastructure and natural resources. The three best performing countries for each supply chain are assessed based on their potential biomass and hydrogen production and exports to the EU by 2050 considering distinct scenarios (realistic and ambitious) for each energy product. The scenarios account for the size of the EU’s demand for biomass and hydrogen respectively in 2050, with hydrogen also containing an average scenario taking into account the average of the forecasted EU energy demanded in existing research. The results show that the best suited African countries for the export of biomass to the EU are Morocco, Egypt and South Africa, while for hydrogen these include Morocco, Egypt and Algeria. It is also found that in a realistic scenario, 5,7% of the EU’s import demand for biomass and 100% of its import demand for green hydrogen could be fulfilled by the top three supplier countries in each case. In the average hydrogen scenario, 33,7% of the EU’s import demand would be fulfilled. For the ambitious scenario, 4% of the biomass import demand and 4,2% of the EU’s hydrogen import demand would be met. The lower percentages of coverage in the ambitious scenario are due to the significantly larger demand of biomass and hydrogen with respect to the realistic scenario. The research finds that across all scenarios, African countries will be able to meet their own demand for biomass and hydrogen through domestic production, except for South Africa which will not be able to fulfil its demand entirely by itself. Additionally, the research highlights important policy areas which need to be considered, which include setting clearer goals for biomass and hydrogen, and encouraging the development of renewable energy demand in Africa and the EU.

This thesis compares the performance of hypothetical biorefineries in Brazil and Scandinavia that produce biofuel for use in large marine vessels using one of three thermochemical technologies—hydrothermal liquefaction (HTL), fast pyrolysis with hydrodeoxygenation (FP), and gasification with Fischer-Tropsch synthesis (GFT)—and one of ten lignocellulosic residues from forestry and agriculture. The biorefineries were modeled using black-box mass balances for biofuel production and electricity and heat cogeneration. The results of this model, along with local costs factors, were used to estimate the economic performance of biorefineries in each country where each feedstock is available. Estimates of capital expenses, operating expenses, and annual earnings were used to calculate the minimum selling price of the biofuel, which is used as an indicator of economic performance. The environmental performance of each combination was estimated using the indicators of life cycle greenhouse gas emissions, sulfur dioxide emissions, nitrogen oxide emissions, and non-renewable energy use. The economic and environmental indicators for each feedstock-technology-country combination are compared to each other and also compared to reference values for other marine emission-reducing technologies, including liquid natural gas, emission scrubbers, and soy biodiesel. The results are subject to sensitivity analysis to determine the influence of uncertainty of capital costs, feedstock costs, biorefinery scale, biorefinery siting, biorefinery configuration, biofuel yields, biofuel blending, and environmental impact allocation. The biofuels modeled in this study have significantly lower life cycle greenhouse gas and sulfur dioxide emissions and non-renewable energy use than those of heavy fuel oil, but have higher life cycle nitrogen oxide emissions, due to the lower quality of the fuel produced and combusted. Economically, none of the biofuels are competitive with current fossil fuel prices when estimated with the scale and cost factors in this study. The feedstock-technology-country combinations with the lowest minimum biofuel selling price, when considered as a ratio to the current local price of marine gas oil, are the hydrothermal liquefaction of barley straw in Sweden, and the fast pyrolysis of corn stover and rice residues in Brazil. Each of those combinations has a minimum biofuel selling price ratio of 3.2 times that of marine gas oil. Performance trends between technologies and feedstocks are weak, and superior economic performance does not correlate with superior environmental performance.