Abstract
Methane is the main component in natural gas, shale gas and methane clathrates. With the depletion of petroleum reserves and as the least CO2 intensive fossil fuel, it will become the most important hydrocarbon feedstock for the synthesis of fuels and chemicals. At this moment a significant fraction of methane (near 32%) is burned for residential heating and industrial power generation. Industry uses around 39% of the methane produced, both for heating and as raw material. Only a tiny fraction (much less than 3%) is used as transportation fuel.
Significant budgets and effort have been invested in recent years in the search for alternative methane utilization routes that do not involve the use of syngas and do not require the associated required scale of operation and investment involved. Despite the increased interest in methane activation, there is yet little to none industrial implementation. In this PDEng design study, the aim is to generate an overview of processing alternative for syngas-free routes for utilization of methane.
After a broad literature review of proposed and studied processes for direct methane conversion, the selective anaerobic oxidation of methane to methanol was chosen. This promising route was first deeply investigated based on available literature. Then, as a part of the project, proof-of-principle experiments were conducted. The experimental section confirmed that production of methanol via this route is indeed possible. Based on the data from the experiments, information available in literature and consultations with one of the research groups investigating this process, a design for a commercial plant was made. This work is the first work aiming at scaling up this process.
The process plant design was the main part of this work. The plant was designed for the capacity of 150 tMeOH per day. The reaction occurs at mild conditions (200°C and 37 bar). Based on the assumed process conditions, a configuration with six fixed beds was chosen. First, the base design was made and then some optimization and alternatives for potential improvement were investigated. The economical estimation of the process showed that the total annual production cost is however higher than the annual sales.
To evaluate how far is this process from a large-scale implementation, a further sensitivity analysis was made. The results showed that to reach a positive return of investment after 14 years, the market price of the product has to increase by a minimum of 10% with a minimum increase of the annual production of 20%. Besides, different factors such as water content, copper loading, cycle time and life time of the catalyst need to be improved. All detailed calculations, assumptions, design and economical evaluations are presented in this work.
Significant budgets and effort have been invested in recent years in the search for alternative methane utilization routes that do not involve the use of syngas and do not require the associated required scale of operation and investment involved. Despite the increased interest in methane activation, there is yet little to none industrial implementation. In this PDEng design study, the aim is to generate an overview of processing alternative for syngas-free routes for utilization of methane.
After a broad literature review of proposed and studied processes for direct methane conversion, the selective anaerobic oxidation of methane to methanol was chosen. This promising route was first deeply investigated based on available literature. Then, as a part of the project, proof-of-principle experiments were conducted. The experimental section confirmed that production of methanol via this route is indeed possible. Based on the data from the experiments, information available in literature and consultations with one of the research groups investigating this process, a design for a commercial plant was made. This work is the first work aiming at scaling up this process.
The process plant design was the main part of this work. The plant was designed for the capacity of 150 tMeOH per day. The reaction occurs at mild conditions (200°C and 37 bar). Based on the assumed process conditions, a configuration with six fixed beds was chosen. First, the base design was made and then some optimization and alternatives for potential improvement were investigated. The economical estimation of the process showed that the total annual production cost is however higher than the annual sales.
To evaluate how far is this process from a large-scale implementation, a further sensitivity analysis was made. The results showed that to reach a positive return of investment after 14 years, the market price of the product has to increase by a minimum of 10% with a minimum increase of the annual production of 20%. Besides, different factors such as water content, copper loading, cycle time and life time of the catalyst need to be improved. All detailed calculations, assumptions, design and economical evaluations are presented in this work.
| Original language | English |
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| Awarding Institution |
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| Award date | 24 Jan 2019 |
| Place of Publication | Enschede |
| Publisher | |
| Publication status | Published - 24 Jan 2019 |