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•Biomass gasification coupled with PEM electrolysis doubles overall efficiency.•The produced methanol can be carbon-negative along its entire lifecycle.•Renewable methanol is ...competitive with fossil fuels at high carbon credits.•Biofuels represent key opportunities for lower carbon intensity of shipping.•Forest residue quantities in California can meet high shipping fuel demand.
At scale, biomass-based fuels are seen as long-term alternatives to conventional shipping fuels to reduce greenhouse gas emissions in the maritime sector. While the operational benefits of renewable methanol as a marine fuel are well-known, its cost and environmental performance depend largely on production method and geographic context. In this study, a techno-economic and environmental assessment of renewable methanol produced by gasification of forestry residues is performed. Two biorefinery systems are modeled thermodynamically for the first time, integrating several design changes to extend past work: (1) methanol synthesized by gasification of torrefied biomass while removing and storing underground a fraction of the carbon initially contained in it, and (2) integration of a polymer electrolyte membrane (PEM) electrolyzer for increased carbon efficiency via hydrogen injection into the methanol synthesis process. The chosen use case is set in California, with forest residue biomass as the feedstock and the ports of Los Angeles and Long Beach as the shipping fuel demand point. Methanol produced by both systems achieves substantial lifecycle greenhouse gas emissions savings compared to traditional shipping fuels, ranging from 38 to 165%, from biomass roadside to methanol combustion. Renewable methanol can be carbon-negative if the CO2 captured during the biomass conversion process is sequestered underground with net greenhouse gas emissions along the lifecycle amounting to −57 gCO2eq/MJ. While the produced methanol in both pathways is still more expensive than conventional fossil fuels, the introduction of CO2eq abatement incentives available in the U.S. and California could bring down minimum fuel selling prices substantially. The produced methanol can be competitive with fossil shipping fuels at credit amounts ranging from $150 to $300/tCO2eq, depending on the eligible credits.
The comprehensive utilization of biomass to obtain energy‐storage carbonaceous materials with special microstructures is of great significance. Herein, a universal method is proposed to fabricate ...oriented carbon microspheres (OCMSs) and 3D porous carbon (3DPC) block at the same time via high‐temperature hydrothermal “disproportionation” of biomass including but not limited to basswood, pinus sylvestris, red walnut, beech, bamboo, and sorghum straw. Through nuclear magnetic resonance, gas chromatography mass spectrometry, as well as various morphologic and structural characterizations, it is demonstrated that OCMS with (002) orientation originates from the carbonization of organic matters produced by the successive decomposition of hemicellulose, cellulose, and lignin during the high‐temperature hydrothermal process, while the 3DPC blocks exhibit abundant sp3 defects and micropores with a surface area of 855.12 m2 g−1 due to the constant loss of organic components from basswood blocks. As a result, the OCMS anode exhibits a high capacity of 201.1 mA h g−1 at 2000 mA g−1 after 2000 cycles, 3DPC cathode delivers a capacity of 95.7 mA h g−1 at 1.0 A g−1 after 5000 cycles. Remarkably, the as‐assembled OCMS//3DPC potassium ion hybrid capacitor exhibits an energy of 140.7 Wh kg−1 at 643.8 W kg−1, with a long cycle life over 8500 cycles.
A high‐temperature hydrothermal induced disproportionation‐like process is developed for converting biomass (including but not limited to basswood, pinus sylvestris, red walnut, beech, bamboo, and sorghum straw) into two types of carbon: oriented carbon microspheres anode and a 3D porous carbon cathode with abundant sp3 defects and large surface area (855.12 m2 g−1) for a high‐performance potassium ion hybrid capacitor.
Aims
Nitrogen is correlated with plant biomass and Cd concentration, collectively influencing phytoextraction of Cd-polluted soil. The Cd phytoextraction by hyperaccumulating plants and high biomass ...plants as affected by nitrogen remains elusive.
Methods
Sweet sorghum (
Sorghum bicolor
(L.) Moench), a high biomass energy plant, and
Solanum nigrum
L., a Cd hyperaccumulator were investigated. Plant growth, Cd accumulation and soil properties as affected by different forms and dosages of nitrogen supply in Cd-polluted soil were studied. Additionally, rhizosphere soil bacterial and fungal community changes of the two species and their relationships with plant Cd accumulation were determined.
Results
A high level of nitrate resulted in the highest and equal Cd accumulation in shoots of the two plants. Sweet sorghum exhibited high photosynthesis rates with capacity for bioethanol production, enabling the re-utilization of post-harvested Cd materials. Consequently, sweet sorghum demonstrated a greater potential for Cd phytoextraction than
S. nigrum
. Regarding microbial community, clay was the driving factor influencing rhizosphere soil bacterial community in sweet sorghum as affected by nitrogen under Cd stress, while soil available Cd played a vital role in
S. nigrum
. Moreover,
Pseudomonas
and AKYG1722 bacteria showed a positive correlation with shoot Cd accumulation in sweet sorghum. AKYG1722,
Sphingobium herbicidovorans
,
Sphingobium chlorophenolicum
,
Streptomyces scabiei
,
Devosia
sp. I507,
Bacillus simplex
and
Ensifer meliloti
were positively correlated with shoot Cd accumulation in
S. nigrum
.
Conclusions
Nitrate performs better than ammonium and urea for improving phytoremediation of Cd-polluted soil using sweet sorghum and
S. nigrum
, but their rhizosphere soil microbial communities were species-dependent.
Graphical abstract
The rapid depletion of conventional fossil fuels and day-by-day growth of environmental pollution due to extensive use of fossil fuels have raised concerns over the use of the fossil fuels; and thus ...search for alternate renewable and sustainable sources for fuels has started in the last few decades. In this context biomass derived fuels seems to be the promising path; and various routes are available for the biomass processing such as pyrolysis, transesterification, hydrothermal liquefaction, steam reforming, etc.; and the hydrothermal liquefaction (HTL) of wet biomass seems to be the promising route. Therefore, this article briefly enlightened a few concepts of HTL such as the elemental composition of bio-crude obtained by HTL, different types of feedstock adopted for HTL, mechanism of HTL processes, possible process flow diagrams for HTL of both wet and dry biomass and energy efficiency of the process. In addition, this article also enlisted possible future research scope for concerned researchers and a few of them are setting up HTL plant suitable for both wet and dry biomass feedstock; analyzing influence of parameters such as temperature, pressure, residence time, catalytic effects, etc.; deriving optimized pathways for better conversion; and development of theoretical models representing the process to the best possible accuracy depending on nature of feedstock.
The purpose of this study was to evaluate the effect of ash from combustion of plant biomass of energy willow and Pennsylvania fanpetals on yields of willow grown as an energy crop and on soil ...properties. A three-year pot experiment was carried out on substrates with a loamy sand texture. Ash application rates were based on the potassium fertilisation demand. An incubation experiment was carried out to determine the effect of biomass-based ash on soil properties. Three soils with textural categories were incubated for 3 months with the ashes, the doses of which were determined on the basis of the hydrolytic acidity of soils (¼; ½ and 1.0 Hh). It was found that ashes generated from burning willow or Pennsylvania fanpetals can be applied instead of phosphorus, potassium and magnesium fertilisers in the cultivation of energy willow. The plant uptake of P, K and Mg from the ashes did not diverge from their absorption by plants when supplied with mineral salts. The application of these alkaline ashes will increase the soil content of phytoavailable forms of phosphorus, potassium and magnesium. The examined ashes enriched the soil with micronutrients.
Other way round: 1H and 13C NMR spectroscopy on isotopically labeled glucose reveals that in the presence of tin‐containing zeolite Sn‐Beta, the isomerization reaction of glucose in water proceeds by ...way of an intramolecular hydride shift (see scheme) rather than proton transfer. This is the first mechanistic demonstration of Sn‐Beta acting as a Lewis acid in a purely aqueous environment.
To mitigate increasing environmental pressures, biomass is becoming a crucial alternative energy source worldwide. Ash fusion characteristics of biomass has closely related to ash-related problems ...during its conversion. The fusion characteristics of cotton stalk (CS), the deposition from CS vibrating grate furnace combustion (DCS), and their modification mechanisms were investigated. The results indicate the sintering temperature (Ts) and ash fusion temperature (AFT) of DCS are lower than that of CS. Kaolinite causes obvious increases in the Ts and flow temperature, while the additions of calcite and Ca-sludge waste (Ca-W) make Dcs deformation temperature increase more obviously than that of flow temperature. That an increase in kalsilite content and leucite formation make the mixture Ts and AFT increase with increasing kaolinite proportion; the replacement of K+ in the silicates by Ca2+ causes the formations of high melting point Ca2+ silicates (e.g., rankinite and wollastonite) with increasing calcite or Ca-W, which makes their Ts and AFT increase. It is found that the deformation temperature corresponds to the temperature at which its liquid phase content at 15% or so based on FactSage calculation.
A significant increase in reactive nitrogen (N) added to terrestrial ecosystems through agricultural fertilization or atmospheric deposition is considered to be one of the most widespread drivers of ...global change. Modifying biomass allocation is one primary strategy for maximizing plant growth rate, survival, and adaptability to various biotic and abiotic stresses. However, there is much uncertainty as to whether and how plant biomass allocation strategies change in response to increased N inputs in terrestrial ecosystems. Here, we synthesized 3516 paired observations of plant biomass and their components related to N additions across terrestrial ecosystems worldwide. Our meta‐analysis reveals that N addition (ranging from 1.08 to 113.81 g m−2 year−1) increased terrestrial plant biomass by 55.6% on average. N addition has increased plant stem mass fraction, shoot mass fraction, and leaf mass fraction by 13.8%, 12.9%, and 13.4%, respectively, but with an associated decrease in plant reproductive mass (including flower and fruit biomass) fraction by 3.4%. We further documented a reduction in plant root‐shoot ratio and root mass fraction by 27% (21.8%–32.1%) and 14.7% (11.6%–17.8%), respectively, in response to N addition. Meta‐regression results showed that N addition effects on plant biomass were positively correlated with mean annual temperature, soil available phosphorus, soil total potassium, specific leaf area, and leaf area per plant. Nevertheless, they were negatively correlated with soil total N, leaf carbon/N ratio, leaf carbon and N content per leaf area, as well as the amount and duration of N addition. In summary, our meta‐analysis suggests that N addition may alter terrestrial plant biomass allocation strategies, leading to more biomass being allocated to aboveground organs than belowground organs and growth versus reproductive trade‐offs. At the global scale, leaf functional traits may dictate how plant species change their biomass allocation pattern in response to N addition.
A meta‐analysis was conducted to examine the effects of N addition on plant biomass allocation strategies in terrestrial ecosystems worldwide. The study synthesized 3516 paired observations of plant biomass and its components in response to N additions, revealing that N addition increased terrestrial plant biomass by 55.6% on average. The study further documents a shift in biomass allocation towards aboveground organs at the expense of belowground organs and reproductive biomass. Meta‐regression results suggest that leaf functional traits may dictate how plants change their biomass allocation pattern in response to N addition.
Climate change issues are calling for the design of renewable sources of energy. In particular, biomass energy from algae is encouraging because production of algae at the commercial scale can be ...done successfully with various techniques. Here, we review the conversion of algal biomass into energy by fast, slow, microwave and catalytic pyrolysis. The article details algae classification; cultivation of macroalgae and microalgae; pyrolysis parameters; production of biochar, bio-oil and biogas; and types of pyrolysis.
Due to increasing anthropogenic activities, especially industry and transport, the fossil fuel demand and consumption have increased proportionally, causing serious environmental issues. This ...attracted researchers and scientists to develop new alternative energy sources. Therefore, this review covers the biofuel production potential and challenges related to various feedstocks and advances in process technologies. It has been concluded that the biofuels such as biodiesel, ethanol, bio-oil, syngas, Fischer–Tropsch H2, and methane produced from crop plant residues, micro- and macroalgae and other biomass wastes using thermo-bio-chemical processes are an eco-friendly route for an energy source. Biofuels production and their uses in industries and transportation considerably minimize fossil fuel dependence. Literature analysis showed that biofuels generated from energy crops and microalgae could be the most efficient and attractive process. Recent progress in the field of biofuels using genetic engineering has larger perspectives in commercial-scale production. However, its large-scale production is still challenging; hence, to resolve this problem, it is essential to convert biomass in biofuels by developing novel technology to increase biofuel production to fulfil the current and future energy demand.
•Emerging technologies for biofuel production are reviewed.•Current and future biofuels' demands are studied.•Engineered bioprocesses for biofuels production from are revisited.•Biofuels are seen to have a huge commercial potential in the future.
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