Analysis of biomass hydrothermal liquefaction and biocrude-oil upgrading for renewable jet fuel production: The impact of reaction conditions on production costs and GHG emissions performance

Component input materials and activities of a model pot-in-pot (PIP) production system were analyzed using life cycle assessment methods. The impact of each component on global warming potential (GWP; kilograms of CO2-equivalent), or carbon footprint, and variable production costs was determined for a 5 cm caliper Acer rubrum L. ‘October Glory’ in a #25 container. Total greenhouse gas emissions (GHG) of inputs and processes at the nursery gate for a defined model system were 15.317 kg CO2e. Carbon sequestration weighted over a 100-year assessment period was estimated to be 4.575 kg CO2, yielding a nursery gate GWP of 10.742 kg CO2e. The major contridbutors to the GWP at the nursery gate were the substrate, production container, the 1.8 m (6 ft), branched, bare root liner, PIP system installation, and fertilization while the liner and production container also contributed significantly to the variable costs. Input materials and labor constituted about 76 and 21% of variable costs, respectively. Unlike field production systems, equipment use in PIP production accounted for only 13% of GHG emissions and 2% of variable costs.

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The Impact of Weather and Slope Conditions on the Productivity, Cost, and GHG Emissions of a Ground-Based Harvesting Operation in Mountain Hardwoods

Forests ◽

10.3390/f12121612 ◽

2021 ◽

Vol 12 (12) ◽

pp. 1612

Author(s):

Sättar Ezzati ◽

Farzam Tavankar ◽

Mohammad Reza Ghaffariyan ◽

Rachele Venanzi ◽

Francesco Latterini ◽

...

Keyword(s):

Ghg Emissions ◽

Timber Harvesting ◽

Operating Conditions ◽

Production Costs ◽

Cost Models ◽

Mixed Stands ◽

Average Delay ◽

Productivity Cost ◽

Steep Slopes ◽

The Impact

Mountainous hardwood mixed stands offer challenges to timber harvesting operations in practice, including a harsh climate, variable topography, steep terrain, and large-sized timbers. This paper aims to develop productivity and cost models for a mountain-ground-based harvesting operation across the terrain (e.g., slope conditions), stand (e.g., tree volume) environmental (e.g., weather), and yard (e.g., winching distance) variables and to assess GHG emissions related to the equipment in use. This development was implemented in a timber harvesting practice under single-tree selection in mountainous forests of Iran where a motor-manual chainsaw is used for felling and a rubber-tired cable skidder is used for log extraction. The average delay-free productivity was 4.55 m3 for felling and 14.73 m3 h−1for skidding. Lower production costs and higher productivity rates were observed over the gentle slopes and in sunny conditions. The average production costs ranged between USD 4.27m−3 for felling and USD 5.35m−3 for skidding. The average emissions ranged between 0.96 kg m−3 for felling and 7.06 kg m−3 for skidding in snowy conditions over steep slopes. The study’s results confirm avoiding harvesting operations on steep slopes (greater than 35%) and in extreme weather conditions to obtain higher work efficiency and to minimize adverse effects of machinery on forest ecosystems. The results should be of use to harvest managers and forest planners considering the application of ground-based harvesting operations using a semi-mechanized system on a range of operating conditions in mountain hardwood stands.

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Geographical Potential of Solar Thermochemical Jet Fuel Production

Energies ◽

10.3390/en13040802 ◽

2020 ◽

Vol 13 (4) ◽

pp. 802

Author(s):

Christoph Falter ◽

Niklas Scharfenberg ◽

Antoine Habersetzer

Keyword(s):

Life Cycle ◽

The United States ◽

Jet Fuel ◽

Production Costs ◽

Solar Irradiation ◽

Fuel Production ◽

Capital Costs ◽

Fuel Demand ◽

Solar Thermochemical ◽

Whole Life Cycle

The solar thermochemical fuel pathway offers the possibility to defossilize the transportation sector by producing renewable fuels that emit significantly less greenhouse gases than conventional fuels over the whole life cycle. Especially for the aviation sector, the availability of renewable liquid hydrocarbon fuels enables climate impact goals to be reached. In this paper, both the geographical potential and life-cycle fuel production costs are analyzed. The assessment of the geographical potential of solar thermochemical fuels excludes areas based on sustainability criteria such as competing land use, protected areas, slope, or shifting sands. On the remaining suitable areas, the production potential surpasses the current global jet fuel demand by a factor of more than fifty, enabling all but one country to cover its own demand. In many cases, a single country can even supply the world demand for jet fuel. A dedicated economic model expresses the life-cycle fuel production costs as a function of the location, taking into account local financial conditions by estimating the national costs of capital. It is found that the lowest production costs are to be expected in Israel, Chile, Spain, and the USA, through a combination of high solar irradiation and low-level capital costs. The thermochemical energy conversion efficiency also has a strong influence on the costs, scaling the size of the solar concentrator. Increasing the efficiency from 15% to 25%, the production costs are reduced by about 20%. In the baseline case, the global jet fuel demand could be covered at costs between 1.58 and 1.83 €/L with production locations in South America, the United States, and the Mediterranean region. The flat progression of the cost-supply curves indicates that production costs remain relatively constant even at very high production volumes.

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What Are the Policy Impacts on Renewable Jet Fuel in Sweden?

Energies ◽

10.3390/en14217194 ◽

2021 ◽

Vol 14 (21) ◽

pp. 7194

Author(s):

Jenny Trinh ◽

Fumi Harahap ◽

Anton Fagerström ◽

Julia Hansson

Keyword(s):

Ghg Emissions ◽

Policy Instruments ◽

Biomass Gasification ◽

Carbon Price ◽

Jet Fuel ◽

Hydrothermal Liquefaction ◽

Aviation Industry ◽

Low Carbon ◽

Effective Policy ◽

Policy Impacts

The aviation industry contributes to more than 2% of global human-induced CO2-emissions, and it is expected to increase to 3% by 2050 as demand for aviation grows. As the industry is still dependent on conventional jet fuel, an essential component for a carbon-neutral growth is low-carbon, sustainable aviation fuels, for example alternative drop-in fuels with biobased components. An optimization model was developed for the case of Sweden to examine the impacts of carbon price, blending mandates and penalty fee (for not reaching the blending mandate) on the production of renewable jet fuel (RJF). The model included biomass gasification-based Fischer–Tropsch (FT) jet fuel, Power-to-Liquid (PTL) jet fuel through the FT route and Hydrothermal liquefaction (HTL)-based jet fuel. Thus, this study aims at answering how combining different policies for the aviation sector can support the production of RJF in Sweden while reducing greenhouse gas (GHG) emissions. The results demonstrate the importance of implementing policy instruments to promote the production of RJF in Sweden. The blending mandate is an effective policy to both promote RJF production while reducing emissions. The current level of the penalty fee is not sufficient to support the fuel switch to RJF. A higher blending mandate and carbon price will accelerate the transition towards renewable and sustainable fuels for the aviation industry.

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Analysis of the Potential for Reducing Life Cycle Greenhouse Gas Emissions from Motor Fuels

Energies ◽

10.3390/en14133744 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3744

Author(s):

Delfina Rogowska ◽

Artur Wyrwa

Keyword(s):

Life Cycle ◽

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Ghg Emissions ◽

Low Carbon ◽

Fuel Production ◽

Gas Emissions ◽

Motor Fuels ◽

Process Heating ◽

The Impact

The assessment of life cycle greenhouse gas emissions of motor fuels is important due to the legal obligations and corporate social responsibility of the petroleum industry. Combining the Life-Cycle Assessment with optimization methods can provide valuable support in the decision-making process. In this paper, a mathematical model of a refinery was developed to analyze the impact of process optimization on GHG emissions at the fuel production stage. The model included ten major refinery units. Fuel production costs were minimized by taking into account the number of constraints. The analysis was performed in two steps. First, the model was run for the reference case of fuels composition. Then, more than twelve thousand model runs were performed. In each model, the fuel composition was changed. This change represented the exogenous pressures and resulted in different flows of mass, energy and GHG emission at the refinery. The most favorable results in terms of GHG emissions were then identified and analyzed. Additionally, the impact of using low-carbon fuels for process heating was evaluated. The study showed that fuel blending management could lead to the reduction of GHG emissions by 0.4 gCO2-eq/MJ while the use of low-carbon fuel for process heating results in a reduction of GHG emissions by 2 ca. gCO2-eq/MJ.

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Renewable Diesel Blendstocks and Biopriviliged Chemicals Distilled from Algal Biocrude Oil Converted via Hydrothermal Liquefaction

10.26434/chemrxiv.9630695 ◽

2019 ◽

Author(s):

Wan-Ting (Grace) Chen ◽

Zhenwei Wu ◽

Buchun Si ◽

Yuanhui Zhang

Keyword(s):

Oxidation Stability ◽

Ash Content ◽

Hydrothermal Liquefaction ◽

Fractional Distillation ◽

Chemical Compositions ◽

Steam Temperature ◽

Renewable Diesel ◽

Commodity Chemicals ◽

Biocrude Oil ◽

Specification Analysis

This study aims to produce renewable diesel and biopriviliged chemicals from microalgae that can thrive in wastewater environment. <i>Spirulina</i> (SP) was converted into biocrude oil at 300ºC for a 30-minute reaction time via hydrothermal liquefaction (HTL). Next, fractional distillation was used to separate SP-derived biocrude oil into different distillates. It was found that 62% of the viscous SP-derived biocrude oil can be separated into liquids at about 270ºC (steam temperature of the distillation). Physicochemical characterizations, including density, viscosity, acidity, elemental compositions, higher heating values and chemical compositions, were carried out with the distillates separated from SP-derived biocrude oil. These analyses showed that 15% distillates could be used as renewable diesel because they have similar heating values (43-46 MJ/kg) and carbon numbers (ranging from C8 to C18) to petroleum diesel. The Van Krevelan diagram of the distillates suggests that deoxygenation was effectively achieved by fractional distillation. In addition, GC-MS analysis indicates that some distillates contain biopriviliged chemicals like aromatics, phenols and fatty nitriles that can be used as commodity chemicals. An algal biorefinery roadmap was proposed based on the analyses of different distillates from the SP-derived biocrude oil. Finally, the fuel specification analysis was conducted with the drop-in renewable diesel, which was prepared with 10 vol.% (HTL10) distillates and 90 vol.% petroleum diesel. According to the fuel specification analysis, HTL10 exhibited a qualified lubricity (<520 µm), acidity (<0.3 mg KOH/g) and oxidation stability (>6 hr), as well as a comparable net heat of combustion (1% lower), ash content (29% lower) and viscosity (17% lower) to those of petroleum diesel. Ultimately, it is expected that this study can provide insights for potential application of algal biocrude oil converted via HTL.

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The Impact of Plant Protection Systems on the Productivity of Soybean Varieties under Irrigated Conditions

Scientific and Technical Bulletin of the Institute of Oilseed Crops NAAS ◽

10.36710/ioc-2019-28-11 ◽

2019 ◽

pp. 109-117

Keyword(s):

Plant Protection ◽

Crop Protection ◽

Production Costs ◽

Protection System ◽

Average Weight ◽

The South ◽

Biological Origin ◽

Chemical Protection ◽

Protection Systems ◽

The Impact

The application of preparations of biological origin in the protection system of soybean grown under conditions of intensive irrigated crop rotations conforms to the modern tendencies of science and production development. The use of them contributes to solving ecological, production and social-economic problems. The study presents the three-year research on the efficiency of systems protecting soybean from pests and diseases based on biological and chemical preparations. The research was conducted in typical soil and climate conditions of the South of Ukraine. Zonal agricultural methods and generally accepted research methodology were used. The purpose of the research was to create a soybean protection system based on preparations of biological origin, ensuring high productivity of high-quality products reducing a negative impact of the crop production on the environment. The study emphasizes that, under irrigated conditions of the South of Ukraine, the application of biological preparations has a positive impact on the indexes of growth, development and formation of the elements of soybean yield structure. There was an increase in the crop biological weight by 13.8 % and 22.1 % and the number of seeds per plant rose by 11.6 and 14.6 % as a consequence of eliminating harmful organisms with the plant protection systems. The larger ground mass was formed by medium-ripe varieties Danai and Svyatogor, on which the increase from protection measures was higher. Weight 1000 pcs. the seeds did not undergo significant changes. It is established that the larger seeds were formed by Danaya and Svyatogor varieties, in which the average weight is 1000 pcs. seeds were 142 and 136 g, respectively, while in the variety Diona this figure was 133 g. There was an increase in the height of the lowest pod when the total plant height rose. For medium-ripe varieties was characterized by a higher attachment of beans, where the highest values of this indicator acquired in the variety Svyatogor. The medium maturing soybean variety Danaia formed the maximum yield of 3.23 and 3.35 t/ha respectively, when biological and chemical protection systems were applied. The research establishes that the application of the bio-fungicide Psevdobakterin 2 (2.0 l/ha) in the crop protection system at the beginning of soybean flowering and the bio-fungicide Baktofit (2.5 l/ha) with the bio-insecticide Lepidotsid-BTU (10.0 l/ha) at the beginning of pod formation does not reduce the productivity of the soybean varieties under study considerably, when compared to the application of chemical preparations. The research determines that the soybean protection system under study ensures a decrease in the coefficient of soybean water uptake by 7.2-13.0 %, increasing the total water intake to an inconsiderable degree. Biologization of the soybean crop protection system leads to a reduction in production costs compared to the chemical protection system. Taking into account the needs for the collection of additional products, costs increase by an average of 1 thousand UAH/ha, while for chemical protection systems by 1.8 thousand UAH/ha. At the same time, the cost is reduced by 220-360 UAH/t and the profitability of growing crops is increased by 3.8-7.8 %. There has been a reduction in the burden of pesticides on the environment and the production of cleaner products. This indicates the prospect of using the biofungicides Pseudobacterin 2 and Bactophyte and the bioinsecticide Lepidocid-BTU on soybeans to protect plants from pests.

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Modeling and Optimization of Microwave-Based Bio-Jet Fuel from Coconut Oil: Investigation of Response Surface Methodology (RSM) and Artificial Neural Network Methodology (ANN)

Energies ◽

10.3390/en14020295 ◽

2021 ◽

Vol 14 (2) ◽

pp. 295

Author(s):

Mei Yin Ong ◽

Saifuddin Nomanbhay ◽

Fitranto Kusumo ◽

Raja Mohamad Hafriz Raja Shahruzzaman ◽

Abd Halim Shamsuddin

Keyword(s):

Statistical Tests ◽

Coconut Oil ◽

Jet Fuel ◽

Molar Ratio ◽

Ann Model ◽

Fuel Production ◽

Turbine Engine ◽

Renewable Fuel ◽

American Society ◽

Better Than

In this study, coconut oils have been transesterified with ethanol using microwave technology. The product obtained (biodiesel and FAEE) was then fractional distillated under vacuum to collect bio-kerosene or bio-jet fuel, which is a renewable fuel to operate a gas turbine engine. This process was modeled using RSM and ANN for optimization purposes. The developed models were proved to be reliable and accurate through different statistical tests and the results showed that ANN modeling was better than RSM. Based on the study, the optimum bio-jet fuel production yield of 74.45 wt% could be achieved with an ethanol–oil molar ratio of 9.25:1 under microwave irradiation with a power of 163.69 W for 12.66 min. This predicted value was obtained from the ANN model that has been optimized with ACO. Besides that, the sensitivity analysis indicated that microwave power offers a dominant impact on the results, followed by the reaction time and lastly ethanol–oil molar ratio. The properties of the bio-jet fuel obtained in this work was also measured and compared with American Society for Testing and Materials (ASTM) D1655 standard.

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An In-Depth Process Model for Fuel Production via Hydrothermal Liquefaction and Catalytic Hydrotreating

Processes ◽

10.3390/pr9071172 ◽

2021 ◽

Vol 9 (7) ◽

pp. 1172

Author(s):

Leonard Moser ◽

Christina Penke ◽

Valentin Batteiger

Keyword(s):

Process Model ◽

Reaction Network ◽

Hydrothermal Liquefaction ◽

Process Chain ◽

Fuel Production ◽

Model Compounds ◽

Point Distribution ◽

Process Step ◽

Elemental Analyses ◽

Made In

One of the more promising technologies for future renewable fuel production from biomass is hydrothermal liquefaction (HTL). Although enormous progress in the context of continuous experiments on demonstration plants has been made in the last years, still many research questions concerning the understanding of the HTL reaction network remain unanswered. In this study, a unique process model of an HTL process chain has been developed in Aspen Plus® for three feedstock, microalgae, sewage sludge and wheat straw. A process chain consisting of HTL, hydrotreatment (HT) and catalytic hydrothermal gasification (cHTG) build the core process steps of the model, which uses 51 model compounds representing the hydrolysis products of the different biochemical groups lipids, proteins, carbohydrates, lignin, extractives and ash for modeling the biomass. Two extensive reaction networks of 272 and 290 reactions for the HTL and HT process step, respectively, lead to the intermediate biocrude (~200 model compounds) and the final upgraded biocrude product (~130 model compounds). The model can reproduce important characteristics, such as yields, elemental analyses, boiling point distribution, product fractions, density and higher heating values of experimental results from continuous experiments as well as literature values. The model can be applied as basis for techno-economic and environmental assessments of HTL fuel production, and may be further developed into a predictive yield modeling tool.

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