Shipping is the backbone of global freight. However, due to its currently strong reliance on fossil fuels, it accounts for 3 % of global greenhouse gas emissions, highlighting both the need and challenge of achieving the required rapid decarbonization. Over the past decade, Onboard carbon capture and storage (OCCS) has gained interest as a potential mitigation strategy while alternative fuels continue to develop. However, several capture technologies could be considered to capture the resulting CO2. In order to identify the most promising ones, this study performs a screening of different capture technologies (including absorption, membrane-assisted liquefaction, adsorption-assisted liquefaction, calcium-looping) through the case of a combination carrier under retrofit and newbuilding scenarios.
Overall, the results indicate that retrofit installations can reduce CO2 emissions by at least 45 %, even when using the existing ship power system. Once the utility (heat and power) is assum... [more]

While he was trapped in a Shell oil refinery for weeks during a 1973 plant strike, Charles R. Cutler (1936-2020) used the opportunity to try out his untested theories on a new method for controlling chemical plants on the actual refinery. They worked spectacularly, and the resulting Dynamic Matrix Control method later became a standard part of control engineering practice. However, DMC was kept a trade secret at Shell until 1980 when it was first made available to the public. This book uncovers the history behind the theory by publishing Cutler’s writings and letters, including his 1969 thesis proposal letter to Prof. Huang at the University of Houston outlining his theories, and a more developed draft paper from 1975 that was never published. Science historians and control engineers alike can trace the development of the theory over time from its earliest origins.

This study introduces a novel and eco-efficient CO2 hydrogenation process design. Following an extensive literature review, Formic Acid (FA) emerged as a viable bulk chemical. A market analysis was performed to estimate feedstock availability. The plant, located in Ravenna, Italy, can produce 50 kta of 85 %wt. FA. The conversion of CO2 and green H2 into FA was meticulously analyzed to identify the best operating conditions and separation technologies, including COPureTM. A key innovation of the sustainable process, simulated in Aspen Plus, is the implementation of Dividing Wall Column (DWC) configuration, which along with heat integration, results in 64% electricity savings, 20% less stream requirements and 51% reduction in CO2 emissions compared to conventional processes. A 2030 economic assessment estimates capital investment and production costs at 73.8 M€ and 41.8 M€/yr respectively, with a profit of 9.5 M€/yr. A sensitivity analysis showed that profitability is heavily impacted by... [more]

Nitrogen-based fertilisers are pivotal for global food security, yet their production is a notable source of greenhouse gas emissions. Urea, a vital fertiliser with significant market presence—19% in Europe and 33% globally—is produced through an energy-demanding process reliant on fossil fuels. This study introduces a ’Green’ Urea plant concept, aimed for implementation in Ravenna, Italy, harnessing exclusively renewable energy sources to foster agricultural sustainability. With a production capacity of 1,300 tonnes per day, this facility neighbours Italy’s first carbon capture and storage (CCS) facility at Ravenna. The core of the proposed methodology is the synthesis of green ammonia. Seawater Reverse Osmosis-Polymer Electrolyte Membrane Electrolysis (SWRO-PEM) and Pressure Swing Adsorption (PSA) yield the necessary hydrogen and nitrogen feedstocks. An enhanced Haber-Bosch process utilising a Ru-based catalyst, facilitating lower operational conditions (500◦C and 100 bar) for the af... [more]

Nowadays, it is crucial to change daily habits to live in a more sustainable world. From an industrial point of view, the capture of CO2 is becoming more and more important in the chemical industry to reduce greenhouse gas emissions and its reuse can be an alternative to fossil resources. Another major challenge for future engineers is the significant increase in the use of renewable energy sources. In this perspective, a process allowing the synthesis of three different olefins from CO2 captured in industrial flue gases and using only wind energy is established. This process is separated into three major sections: water electrolysis, carbon dioxide reduction to produce methanol and methanol-to-olefins synthesis. The targeted production capacity is of 450 000 tonnes per year of olefins, which are considered to be ethylene, propylene and butylene. This process, which involves a complete flowsheet modelling is implemented with the Aspen Plus software. A heat integration is performed to i... [more]

To create useful products from carbon dioxide, electrochemical reduction is of the most promising approaches. Electrochemical reduction can use renewable energy to directly produce useful products such as formic acid, carbon monoxide, methanol or other C2 products. Specifically in Greece, methanol has been proven as a promising alternative for marine fuel, and it has been increasing in demand recently. As such, the proposed design is aimed to target this market. This paper will focus on the production of methanol using direct CO2 electro-reduction using Direct Air Capture (DAC) for the CO2 feed. A mathematical model of the electrolyser was created and implemented in Python. This model was then used alongside renewable energy production data from Open Power Systems [1] to optimise the total annualised cost with the constraint that the plant could only use renewable energy and must produce a minimum methanol flowrate. A combined stochastic search and derivative-free optimisation method w... [more]