Unconventional Biomass Research Articles

Investigating the properties and agronomic benefits of onion peel and chicken feather-derived biochars

Biochar production from unconventional biomass, specifically onion peel (OP) and chicken feathers (CF), was investigated in this study. Two distinct biochars were produced by doping each biomass with the other, with the aim of exploring the synergistic effects of different feedstock combinations on biochar properties. The biochar production process was conducted using a retort heating method and characterized using several techniques. A yield of 36 % was obtained for OP-doped biochar (OP92CF8-BC) and 23 % for CF-doped biochar (F92OP8-BC). Fourier Transform Infrared Spectroscopy analysis revealed characteristic functional groups from cellulose, hemicellulose, and lignin in OP92CF8-BC, while CF92OP8-BC displayed keratin-related peaks. Scanning Electron Microscopy imaging showed surface morphology differences, with OP92CF8-BC exhibiting a rougher and more porous structure compared to CF92OP8-BC. Energy-Dispersive X-ray Spectroscopy analysis confirmed the elemental composition, with OP92CF8-BC having higher carbon, calcium, and sulfur contents and CF92OP8-BC having higher nitrogen and oxygen contents. The biochar had specific surface areas of 342.4 and 200.80 m2/g for OP92CF8-BC and CF92OP8-BC, respectively. According to the results, using biochar treatments-more especially, CF92OP8-BC-can significantly enhance cob weight. This could be good for agricultural productivity. These findings highlight the influence of feedstock composition on the properties of biochar and provide insights for its potential applications in soil amendment and pollutant removal.

Characterization of Wood, Leaves, Barks, and pod wastes from Prosopis africana biomass for biofuel production

One of the approaches for increasing the contribution of biomass to the renewable energy mix is the valorization of biomass to bioenergy. Evaluating the potential of unconventional biomass sources could significantly accelerate the assessment for suitability as feedstock for bioenergy production as a sustainable solution. The study aimed to characterize the Prosopis africana biomass of wood, barks, leaves, and pods towards providing valuable data for scaling up and incorporating these materials into the bioenergy crop database. Characterizations of wood, leaves, barks, and pod wastes from Prosopis africana biomass were investigated based on the proximate, ultimate, and compositional analysis of pulverized samples of the PA biomass to determine their physical, thermal, and chemical properties towards assessing their potential for valorization to bioenergy. The lignocellulosic materials were characterized by scanning electron microscopy, energy dispersive X-ray, Fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction. The results show that the pulverized sample wastes have porous structures with varying degrees of crystallinity (wood: 89.20 %, bark: 23.90 %, leaves: 32.48 %, pods: 23.08 %), suggesting different susceptibilities to conversion processes. Notably, the wood sample had the lowest moisture content (3.13 %), and the pod sample had the highest volatile matter content (75.83 %), indicating a high potential for biofuel production. The higher heating values (HHV) and lower heating values (LHV) of the samples ranged from 15.23 to 20.49 MJ/kg and 13.83 to 18.79 MJ/kg, respectively. These calorific values are competitive with established lignocellulosic bioenergy feedstocks, positioning PA biomass as promising candidates for solid biofuel applications.

Evaluation of the potential utilization of conventional and unconventional biomass wastes resources for energy production

This work presents kinetic and thermal data of three different biomass wastes with high availability in Uruguay. Samples were analysed by proximate, ultimate and thermogravimetric analyses, transient plane source, and a cone calorimeter. DTG results at different heating rates allowed us to identify different stages during the thermogravimetric analysis. Kinetic modelling per stages was realized for each stage observed during the heating of the biomass samples. The kinetic was modelled minimizing the square difference between the experimental data and theoretical values obtained with the model. Activation energy values were obtained for each stage, with values in the range 164-217 kJ mol-1 for the decomposition of cellulose and hemicellulose, and between 190-507 kJ mol-1 for the decomposition of lignin.

Combined Use of TiO2 Nanoparticles and Biochar Produced from Moss (Leucobryum glaucum (Hedw.) Ångstr.) Biomass for Chinese Spinach (Amaranthus dubius L.) Cultivation under Saline Stress

Salinity-induced soil degradation poses a significant challenge to agricultural productivity and requires innovative crop-management strategies. In this study, the synergistic effect of biochar and TiO2 nanoparticles (NPs) obtained from moss (Leucobryum glaucum (Hedw.) Ångstr.) biomass on the growth, yield, biochemical, and enzymatic response of Chinese spinach (Amaranthus dubius L.) grown under salinity stress was investigated. Purposely, A. dubius was grown under different combinations of arable soil, biochar, TiO2 NPs, and saline soils. The produced biochar and TiO2 NPs were characterized using microscopy image analysis, X-ray diffraction patterns (XRD), energy-dispersive X-ray spectroscopy (EDX), zeta potential, particle size distribution, and Fourier-transform infrared spectroscopy (FTIR). The results showed that saline stress caused a significant (p < 0.05) decline in growth, yield, and biochemical constituents of A. dubius compared to control treatments. However, the combined application of biochar and TiO2 NPs significantly (p < 0.05) alleviated the saline stress and resulted in optimum fresh weight (30.81 g/plant), dry weight (4.90 g/plant), shoot and root length (28.64 and 12.54 cm), lead number (17.50), leaf area (12.50 cm2/plant), chlorophyll (2.36 mg/g), carotenoids (2.85 mg/g), and relative water content (82.10%). Biochar and TiO2-NP application helped to reduce the levels of stress enzymes such as catalase (2.93 µmol/min/mg P), superoxide dismutase (SOD: 2.47 EU/g P), peroxidase (POD: 40.03 EU/min/g P), and ascorbate peroxidase (3.10 mM/mg P) in saline soil. The findings of this study suggest that the combination of nanotechnology and biochar derived from unconventional biomass can be a viable option to mitigate salinity-related challenges and enhance crop yield.

Integration of thermoelectric generators in a biomass boiler: Experimental tests and study of ash deposition effect

Thermoelectric generators (TEGs) are based on Seebeck effect and produce electricity from a heat flow. They require low maintenance and provide quiet operation. However, they have low efficiency and need suitable temperature values. Accordingly, the integration of TEGs in boilers is a promising approach, since these equipment present high temperature differences between hot gases and water and allows the use of waste heat for water heating. There are experiences of the integration of TEGs in biomass boilers, but almost none with unconventional biomass with a high tendency to ash deposition. The integration of TEG modules in a commercial pellet-fired 25 kWth boiler is described and experimental results, working with pine pellets and with an agropellet (70% of vineyard pruning and 30% of barley straw), are presented. Power produced with only 6 modules can reach 60 W. After quantifying the effect of the temperature on both gas and water sides, the study focuses on analyzing the ash deposition on the exchange surfaces and their effect on TEG modules operation (e.g. power reduction of 0.24 W per hour with pine and 0.78 with agropellet). This effect can be minimized by working with high excess of air or by integrating a cleaning system.

Algae as an alternative to the methods of production and use of conventional biomass (review article)

Algae have been present in the water treatments technologies, food for animals makingprocesses or even for diet supplements production for many years now. Recent years, however, have brought a number of ideas and discoveries for a wider use of these autotrophs. Their use is related to the broadly understood environmental protection and many threads of combating climate change. Currently, one of the most common ways of using algae is the production of liquid biofuels of the 3 rd and 4 th generation and unconventional biomass generation. Biofuels obtained from algae, in addition to lower amounts of harmful substances contained in them, are often characterized by a negative emission balance. It is related to the fact that those organisms, being in an exponential growth phase, assimilate the carbon dioxideneeded for photosynthesis. The production of energy substances from algae and microalgae in the teeth of draining fossil fuel deposits and their destructive impact on the environment. That sooth combined with the ease and low cost of culture, condition they become a real alternative to existing energy sources. Unique properties of algae linked with the fact that they are among the best, known biological energy converters opens the way to a number of opportunities to use them in other economic sectors. Certainly, the technological revolution in the energy market in addition to the requirement to create the most efficient reactors, in-depth research on the properties of fuels and the producers themselves still needs to be regulated by law. Algae can be grown in polluted waters, and the energy raw materials produced from them are able to reach (without emission logistic costs) a negative balance of 𝐶𝑂2 emissions. This phenomenon and the fact that apart from fuels and biogas, they can be used for purposes such as carbon sequestration, creating energy biomass, medicines and dietary supplements, as well as food for animals, for example, the most reasonable choice would be to create advanced regulations regarding the closed- circuit policy in the energy sector, based precisely on biologically active organisms. This work focuses on gathering and presenting basic information regarding current technologies related to algae, their potential uses in the energy sector, and the long-term prospects for their development. It also takes into account the issues associated with the holistic nature of energy harvesting methods such as the one discussed. Key words: algae, bioeconomy, biofuels, biorefinery

Sustainable Production of Monoraphidium Microalgae Biomass as a Source of Bioenergy

Microalgae are a renewable source of unconventional biomass with potential application in the production of various biofuels. The production of carbon-neutral fuels is necessary for protecting the environment. This work determined the possibility of producing biomass of microalgae belonging to Monoraphidium genus using saline wastewater resulting from proecological salmon farming in the recirculating aquaculture system. The tests were carried out in tubular photobioreactors using LED light. As a part of the analyses, the growth and productivity of microalgal biomass, cell density in culture, and lipid concentration and ash content in biomass were determined. In addition, the concentration of selected phosphorus and nitrogen forms present in wastewater corresponding to the degree of their use by microalgae as a nutrient substrate was determined. The biomass concentration estimated in the tests was 3.79 g·L−1, while the maximum biomass productivity was 0.46 g·L−1·d−1. The cells’ optical density in culture measured at 680 nm was 0.648. The lipid content in biomass was 18.53% (dry basis), and the ash content was 32.34%. It was found that microalgae of the genus Monoraphidium effectively used the nitrogen as well as phosphorus forms present in the wastewater for their growth. The total nitrogen content in the sewage decreased by 82.62%, and total phosphorus content by over 99%. The analysis of the individual forms of nitrogen showed that N-NO3 was reduced by 85.37% and N-NO2 by 78.43%, while orthophosphate (V) dissolved in water was reduced by 99%. However, the content of N-NH4 in wastewater from the beginning till the end of the experiment remained <0.05 mg·L−1.

An experimental study of single unconventional biomass pellets: Ignition characteristics, combustion processes, and artificial neural network modeling

An experimental study of single unconventional biomass pellets: Ignition characteristics, combustion processes, and artificial neural network modeling

Pelletization of wood and alternative residual biomass blends for producing industrial quality pellets

Pellets for industrial use were produced from blends of pine sawdust (PIN) and alternative residual biomasses in a pilot-scale pelletizer. The effect of the pelletization temperature (T = 50–80 °C) and biomass moisture content (MC = 14–20%) on pine sawdust pellet quality was studied by using response surface methodology (RSM). Pelletization performance was evaluated on the basis of the durability, bulk density, moisture content, lower heating value (LHV), energy density, diameter, length and density of the pellets. From the RSM analysis, a maximum durability value of 99.4% was obtained at T = 80 °C and MC = 16.6%. Under these conditions, all the parameters showed values within the required range of industrial pellet qualities, i.e., a bulk density of 616 kg/m3, a pellet moisture content of 7.6%, a lower heating value (as received) of 18 MJ/kg, a diameter of 6.2 mm and a length of 23.4 mm. Blends of pine sawdust with eleven unconventional biomass samples were then pelletized under the optimum conditions to obtain pellets for industrial use according to the categories of quality defined by ISO 17225-2. Blends of pine sawdust with almond shells (AS) and olive stones (OS) contents of up to 30 wt%, as well as with pine cone leafs (PCL) contents of up to 15 wt%, produced I1 pellets. Blends of pine sawdust with coffee dregs (CD), coffee husks (CH) and grape pomace (GP) proportions of up to 10 wt%, as well as with hazelnut shells (HS), miscanthus (MIS), pine kernel shells (PKS) and switchgrass (SG) contents of up to 15 wt%, and also with a PCL content of between 15 and 30 wt%, generated I3 class pellets. Classification was not possible for cocoa shells (CS) mixed with pine sawdust due to the low bulk density of the pellets. Energy consumption resulting from the pelletization of the blends was evaluated with values ranging from 0.09 to 0.33 kWh/kg, while the pelletization of pine sawdust required 0.18 kWh/kg. The addition of alternative biomass feedstocks to pine sawdust may therefore serve to reduce energy consumption in industrial pelletization.

Unconventional biomass fuels for steam gasification: Kinetic analysis and effect of ash composition on reactivity

Twelve commercial and unconventional biomass fuels were evaluated in steam gasification; these include samples of hard (wood, almond, olive and pine kernel wastes) and soft (miscanthus, switchgrass, coffee, cocoa and grape wastes) biomass. Gasification tests at 700–1000 °C of biomass chars obtained from a bubbling fluidized bed reactor were performed in a TG analyzer. Steam gasification kinetics were extensively analyzed: an index of key parameters for the twelve biomasses and the correlation to biomass ash composition were developed. The random pore model (RPM) described the experimental reactivity best, with activation energies of 59–196 kJ mol−1. The study of their reactivities provided a ranking of fast-, medium- and slow-kinetics fuels. The influence of alkaline and alkaline-earth metals (AAEM) on reactivity revealed that K, Na and Mg had a positive effect while Si, P and Ca had a negative influence.

Advanced Characterization of Available not Conventional Mediterranean Biomass Solid Fuels for Ash Related Issues in Thermal Processes

According to the European Biomass Association, bioenergy represents about 60% of the EU’s total consumption of renewables. The EERA Bioenergy, section of the European Energy Research Alliance, indicates that agricultural residues and non-food crops should be used at farm- and village- scales, while low quality biomass and waste could be used for medium- and large- scale power and CHP plants. Among the barriers that hamper the efficient processing of solid fuels in thermal processes, such as combustion and gasification, ash related issues are still challenging for plant operators. These issues include agglomeration in fluidized bed combustion, slag formation, and fouling of convective heat exchangers. Furthermore, advanced characterization methods for solid biomass fuels, especially predictive approaches for ash related issues, are not fully developed. Consequently, the use of unconventional biomass solid fuels is limited because of operating risks. In addition, the availability of the detailed chemical analyses of unconventional fuels is often limited. In this investigation, a validated fuel characterization tool to define the agglomeration - slagging propensity of biomass fuels for their use in thermal processes, is applied to an advanced database of mediterranean (Greece, Italy, Spain) opportunity fuels. The database is built by means of an extensive literature review, including the detailed ash chemical compositions. The input of the tool is the specific fuel ash chemical composition, and the output is the agglomeration - slagging propensity computed as a parameter in the range (0 – 100). In this work it is shown that a high ash fusion temperature (from the Ash Fusion Test) is a necessary but not sufficient condition to low agglomeration and slagging in combustion applications. Among the fuels analyzed, wood, shrubs and citrus industry agro-residues evidenced a low-to-medium median propensity to agglomerate and slag, contrarily to the high propensity of agro-residues (various), wine industry residues, and crops. About 20 opportunity fuels, with low-to-medium agglomeration and slagging propensity and for which environmental, economic and social sustainability has to be further explored, are suggested for thermal applications. Some countermeasures to efficiently process the more challenging fuels are mentioned, including the use of specific combustion additives.

Categorical assessment and characterization of conventional and unconventional biomass resources in Bangladesh

With the rapid industrial growth, the need for renewable energy sources is rising fast. Being a developing country, Bangladesh aims towards industrial expansion, which is always followed by increased energy consumption. Considering the fact that fossil fuel is not sustainable and biomass sources are abundant and offer more versatility, the latter have become an attractive alternative to petroleum-based products. Moreover, utilization of biomass also seems promising because of biodegradability and lower greenhouse gas emissions, ensuring reduced environmental pollution, a grave concern with fossil-fuel technology. Biomass can range from agricultural byproducts to industrial and municipal wastes, however, very few biomass sources are currently being used in Bangladesh. Moreover, biomass can also be utilized to derive valuable chemicals, which are potential raw materials in several existing industries in Bangladesh. Despite having massive potential in Bangladesh, there haven't been organized studies on feedstock types, quantities, characterization and applications. Here we present an organized study to identify potential biomass sources and their available quantities. Considering specific waste fractions from varying sources, total amount of utilizable biomass resources have been calculated. A categorized proximate analysis data summary of varying biomass is also prepared that can be consulted in the future studies to calculate the theoretical possible production of energy as well as useful bio-chemicals based on efficient bio-processing techniques. This work is intended to benchmark the current efforts, and would add valuable information resources for the ongoing research towards achieving energy-sustainability and energy-security in Bangladesh. DOI: http://dx.doi.org/10.3329/cerb.v17i1.22910 Chemical Engineering Research Bulletin 17(2015) 1-10

Comparative life cycle assessment of biodiesel from algae and jatropha: A case study of India

Algae and jatropha, two types of promising and unconventional biomass, are investigated in this study for large-scale production of biodiesel. The aim is to evaluate the potential advantages and the magnitude of closeness of life cycle balances between these two biodiesel pathways compared to fossil diesel, by taking into account possible uncertainties. The geographical location of this study is India with a prospect of utilizing available wastelands in southern regions. The results indicate that the environmental performance of algal biodiesel is comparable to that of jatropha biodiesel. Both show significant GHG emission and fossil energy depletion reductions which are in the range of 36-40 and 10-25% respectively compared to fossil diesel in the studied geographic context.

06/02313 Experimental investigation on combustion and heat transfer characteristics in a furnace fueled with unconventional biomass fuels (date stones and palm stalks): Al-Omari, S.-A. B. Energy Conversion and Management, 2006, 47, (6), 778–790.

06/02313 Experimental investigation on combustion and heat transfer characteristics in a furnace fueled with unconventional biomass fuels (date stones and palm stalks): Al-Omari, S.-A. B. Energy Conversion and Management, 2006, 47, (6), 778–790.

Experimental investigation on combustion and heat transfer characteristics in a furnace fueled with unconventional biomass fuels (date stones and palm stalks)

Abstract The combustion of date stones and palm stalks in a small scale furnace with a conical solid fuel bed is investigated experimentally. This investigation (to the best of the knowledge of the author) is the first addressing date stones as a new renewable energy source. Different experimental conditions are investigated where different fuel feed conditions and different combustion air flow rates are considered. The major results are given in terms of the fuel reduction rates and the heat transferred to the cooling water flowing in a water jacket around the furnace as functions of time. Combustion of the biomass fuels considered here in the investigated furnace is initiated by using LPG fuel as a starter. The hot products of LPG combustion, which is taking place in a burner built prior to the investigated solid fuel furnace, are allowed to penetrate the conical fuel bed for 2–3 min from its bottom base in the upward direction, causing effective heating and gasification and pyrolysis of the solid fuel in the bed to take place. The resulting combustible gases mix with the combustion air and subsequently are ignited by an external ignition source. The results of the present study highlight date stones as a renewable energy source with a good potential.