Pyrolysis Of Bark Research Articles

Kinetic and thermodynamic analysis of Borassus flabellifer bark pyrolysis for effective production of biofuel

Kinetic and thermodynamic analysis of Borassus flabellifer bark pyrolysis for effective production of biofuel

Catalytic pyrolysis of biomass using fly ash leachate to increase carbon monoxide production and improve biochar properties to accelerate anaerobic digestion

Biomass-derived biochar is attracting growing interest as an effective additive for anaerobic digestion (AD). To improve energy yield and digestion performance through an integrated process of biochar production and AD, biochar upgrading using biomass fly ash leachate as a sustainable metal catalyst was investigated. The results indicate that the bark soaked in the leachate improved the pyrolysis reactivity of biomass with CO2 and reduced the temperature at which the reaction rate reached its maximum from 943 °C to 801 °C. This resulted in a doubling of CO production during CO2-assisted pyrolysis at 800 °C. In addition, the combined use of fly ash leachate and CO2 in bark pyrolysis improved not only the porosity of the resulting biochar but also its wettability and liming potential. Moreover, biochar amended with fly ash leachate and CO2 significantly reduced the lag time in the anaerobic digestion of grease trap waste.

Pyrolysis and Extraction of Bark in a Biorefineries Context: A Critical Review

Bark-based biorefineries are estimated to become a trending topic in the coming years, particularly with their adsorbent applications and antioxidant production. While the potential benefits of bark-based biorefineries are well-recognized, it is not known how to develop a bark-based biorefinery considering different unit operations and the potential end products. The characterization and screening of different barks for chemical composition is the initial step in biorefinery development, along with the selection of the relevant conversion processes. This state-of-the-art review provides background knowledge on the pyrolysis and extraction studies of bark as the key conversion operations. The results of recent (2010–2022) bark pyrolysis and extraction studies were critically analyzed for process conditions, product properties, and product yields, as well as a discussion of energy-saving possibilities. A biorefinery scheme was proposed based on these data. The current knowledge gaps were identified and future directions were evaluated, which include the production of charcoals, platform chemicals, and extract profiling for specific applications. The results indicate that barks are particularly rich in hydrophilic extractives with potential antioxidant properties and pyrolysis operations, resulting in functional chars that may be used in value-added applications as adsorbent materials. A biorefinery scheme allows for the production of platform chemicals, antioxidant extracts and biochars from barks while contributing to the reduction of waste and environmental pollution.

Characteristics and liming potential of biochar types from potato waste and pine-bark.

Large amount of wastes are burnt or left to decompose on site or at landfills where they cause air pollution and nutrient leaching to groundwater. Waste management strategies that return these food wastes to agricultural soils recover the carbon and nutrients that would otherwise have been lost, enrich soils and improve crop productivity. This study characterised biochar produced by pyrolysis of potato peels (PP), cull potato (CP) and pine bark (PB) at 350 and 650°C. The biochar types were analysed for pH, phosphorus (P) and other elemental composition. Proximate analysis was done following ASTM standard 1762-84, while surface functional groups and external morphology characteristics were determined using FTIR and SEM; respectively. Pine bark biochar had higher yield and fixed carbon (FC), and lower ash content and volatile matter than biochar types from potato wastes. The liming potential of CP 650°C is greater than that of PB biochars. Biochar types from potato waste had more functional groups even at high pyrolysis temperature relative to pine bark. Potato waste biochars showed an increase in pH, calcium carbonate equivalent (CCE), K and P content with increasing pyrolysis temperature. These findings imply that biochar from potato waste may be valuable for soil C storage, remediating acidity and increasing availability of nutrients especially K and P in acidic soils.

Valorization potential of the aqueous products from hydrothermal liquefaction and stepwise slow pyrolysis of wood bark and hemp hurds with yields and product comparison

Birch bark, spruce bark, and hemp hurds were processed with hydrothermal liquefaction (HTL) and stepwise slow pyrolysis (SSP) and the compositions of the aqueous liquid products were quantitatively compared. The phenolic profiles of the analyzed products were different, but overall they contained similar concentrations of aromatics and phenolic compounds (4–43 mM and 52–215 mM, respectively). The SSP fractional condensation provided liquids with lower water content (appr. 80 % in SSP, 95 % in HTL), but the HTL process was selective e.g. in producing catechols into the aqueous phase. HTL produced higher amounts (15–4406 mmol kg−1) of the analyzed compound groups per dry matter into the aqueous products than SSP (8–1387 mmol kg−1). This study forms a solid basis for feedstock and process optimization considering the future valorization of these liquid products.

Влияние на биовъглен върху добив от царевица и микробиална активност при Алувиално- ливадна почва

A three-year field experiment with maize was carried out on fluvisol. The aim of the present study was to evaluate the impact of biochar on maize yield at different levels of water stress and its effect on the amount of soil microorganisms. The following variants were studied: control with no biochar addition, and variants with biochar. Biochar was applied in 2 t/ha in 2016, produced by pyrolysis of rice straw, then in 3 t/ha in 2017 and 10 t/ha in 2018, both obtained by pyrolysis of oak bark. These variants were divided into three more depending on the irrigation regime: i.e. non-irrigated, irrigation at dT>0 °C, and irrigation at dT<-1 °C. Under non-irrigated conditions, the effect of biochar on maize yield was not pronounced over three years. Under irrigation conditions with water added according to crop water stress, higher yields of maize were obtained in the third year when biochar application to the soil was highest (10 t/ha). Also, yield was higher when faster (at lower water stress dT<-1 °C) irrigation rates were applied. Soil moisture changed slowly in the biochar variants and the best values of the temperature differences were obtained for irrigation at dT<-1 °C in 2018. These results showed that the influence of biochar on soil microbiota was significantly greater, and the most stimulating effect of biochar was obtained for bacterial populations.

Characterization and potential utilization of extracts and pyrolyzates from Jasminum nudiflorum Lindl. Bark

Utilization of lignocellulosic biomass is increasingly important. Jasminum nudiflorum Lindl. (JNL) is a widely cultivated landscape plant in China. To evaluate the chemical components, pyrolysis characteristics as well as the potential values of JNL bark for utilization, the components were extracted using methanol, ethanol, and benzene/ethanol (2:1, v/v) and pyrolyzed from room temperature to 300 °C, respectively. Many components were detected in the extracts and the pyrolyzates of JNL bark and their chemical properties were analyzed. The compounds identified in the extracts and the pyrolyzates of JNL bark included acids, aldehydes, alcohols, esters, ketones, aromatics, saccharides, olefins, and nitrogen-containing compounds. Some of the identified compounds, such as urs-12-en-28-al, 3-(acetyloxy)-, (3.beta.)-, 5-hydroxymethylfurfural, and vanillin, are widely used in the medical, energy, and food industries. The pyrolysis of JNL bark using thermogravimetric (TG) analyzer showed the highest reaction rate occurred at between 200 and 300 °C where the maximum mass loss was observed. According to the Coats-Redfern method, the calculated apparent activation energy (E) and pre-exponential factor (A) of the pyrolysis process of JNL bark were 52.04 kJ mol−1 and 3.14 × 105 min−1, respectively. This research provides information on the components and pyrolysis characteristics of JNL bark, which shows great potential for application in medical, food, and chemical industries.

Catalytic pyrolysis of pine bark over Ni/SiO2 in a CO2 atmosphere

Syngas was produced by catalytic pyrolysis of pine bark (PB) using CO2 as a raw feedstock as part of an effort to realize the sustainable utilization of biomass carbon. An examination of both liquid and gaseous pyrolysates from pyrolysis revealed that CO2 expedited gas-phase reactions (GPRs) with volatile pyrolysates (VPs) evolved from thermolysis of PB. The GPRs between CO2 and VPs led to the generation of CO at ≥ 600 °C regardless of Boudouard reactions. Two-step pyrolysis was conducted with an additional heating source, and the synergetic use of Ni/SiO2 and CO2 stimulated syngas formation at ≤ 600 °C. Evolution of H2 and CO from catalytic pyrolysis at 700 °C in CO2 atmosphere was greater by factors of 10 and 5, respectively, compared with those from two-step pyrolysis. The conditions for catalytic deactivation between virgin and used catalysts were compared using temperature-programmed oxidation. An apparent reduction of organic species on the surface of used catalysts by CO2 indicates that the addition of CO2 suppressed the formation of coke for deposition. Accordingly, combinational use of CO2 and Ni/SiO2 in catalytic pyrolysis can be recommended as an advanced technical option for production of syngas under favorably retarded conditions for catalyst deactivation.

Feasibility of anaerobic digestion as a treatment for the aqueous pyrolysis condensate (APC) of birch bark

Biooil produced via biomass pyrolysis includes an aqueous-acidic phase and a dense and rich organic phase. The aqueous phase has a low heating value and is considered a waste stream. In this study fractional condensation was employed to separate the liquid product of birch bark pyrolysis into an aqueous pyrolysis condensate (APC) and a dense biooil fraction. The APC contained high amounts (~100 g/kg) of acidic acid (AA) and was investigated for anaerobic digestion (AD). The AA in the APC could be converted to biogas, however, it contained elevated concentrations of microbial inhibitors (24 g/kg total phenolics). The inhibiting effect could be mitigated by acclimatization of the microbial population, which in turn converted some of the additional organics. The production of methane further improved with the addition of biochar to adsorb some of the inhibitors. The results imply that a waste product can be converted into a potential energy carrier.

Fractional condensation of pyrolysis vapours as a promising approach to control bio-oil aging: Dry birch bark bio-oil

Bio-oil has several undesired fuel properties such as high viscosity, high acidity, high molecular weight, instability, and phase separation upon aging. Further, the high oxygen content (typically 45–50 wt%) and the water content (typically 15–30 wt%) of pyrolysis oil result in a lower energy density than conventional fuel oils. Whole bio-oil from the fast pyrolysis of birch bark is phase separated at room temperature, probably because of the high extractive content of the bark. It prevents the application of bio-oil derived from birch bark as a fuel. Therefore, the main objective of this research is to investigate the application of fractional condensation of pyrolysis vapors as a promising method to obtain bio-oils that are more resistant to aging. Bio-oil vapors were separated into three cuts: a hard solid in the first condenser, a viscous oily cut (“second condenser cut”) in the second condenser/electrostatic precipitator, and a water-rich acidic liquid in the third condenser. It was found that fractional condensation is an effective method to separate water, acids and other low molecular weight reactive components from bio-oil and is a promising downstream approach to control the quality of bio-oils, making it more suitable for further upgrading and/or direct application. Performing fractional condensation and mixing the second condenser oil fraction with 25% isopropanol yields a very stable liquid fuel.

Improvement of bark pyrolysis oil and value added chemical recovery by pervaporation

Pyrolysis oil produced from forestry residues is used as a low-grade fuel in applications such as heating oil. However, the high water and acid content can lead to fuel instability, phase separation, poor lubrication, and corrosion. In this work, pervaporation has been studied as a process to simultaneously upgrade a pyrolysis oil produced from Canadian softwood bark to meet a boiler fuel standard and extract value-added chemicals. Commercial polyacrylonitrile-supported polyvinyl alcohol membranes from DeltaMem AG were used at temperatures of 60 and 80 °C to separate water and volatile organic components, including methanol, acetic acid, and acetol. A design of experiment study was used to define the range of operating conditions. A temperature of 80 °C and a low feed flow rate of 0.1 mL min−1 resulted in the highest quality oil. The upgraded pyrolysis oil (pervaporation retentate) showed an increased heating value from incomplete combustion to 16.07 MJ kg−1 and the water content was lowered from 70.2 wt% in the feedstock to 21.4 wt%, demonstrating the potential for this process on a larger scale.

Kinetics of thermal pyrolysis of Eucalyptus bark by using thermogravimetric-Fourier transform infrared spectrometry technique

In Southern China, the bark residues from Eucalyptus trees are collected and burned to generate electricity. They are prone to self-heating and even spontaneous combustion when stored in large-scale stockpiles. Pyrolysis plays an important role in these processes. In this work, the pyrolysis characteristics of Eucalyptus bark were investigated by using thermogravimetric analysis coupled with Fourier transform infrared spectrometry. The mass loss process of Eucalyptus bark pyrolysis consists of three stages: dehydration, decomposition of organic matters and decomposition of oxalate, lignin and other components. Except the decomposition of minerals, Eucalyptus bark pyrolysis was described by a four pseudo-component reaction scheme and the kinetic parameters were obtained by using the genetic algorithm. The major evolved gas species and their generation temperature ranges during Eucalyptus bark pyrolysis were identified by Fourier transform infrared spectrometry. It was found that the temperature ranges of the evolved gases were consistent with the decomposition temperature ranges of pseudo-cellulose and pseudo-hemicellulose, in particular with that of pseudo-cellulose.

Quantifying the influence of eucalyptus bark and corncob biochars on the physico-chemical properties of a tropical oxisol under two soil tillage modes

PurposeThis study aimed to assess the impact of two biochars applied at the rate of 15 t ha−1 on physico-chemical parameters of an oxisol in Cameroon.MethodsThe biochars were made from slow pyrolysis (~ 300 °C, 4 h) of eucalyptus tree bark and corncobs and then incorporated into the top 15 cm of the soil with or without straw. The soil tillage mode was either flat plots or furrows and ridges. Soil porosity, bulk density, saturated hydraulic conductivity, available water content, pH, nitrogen, potassium, phosphorus, cation exchange capacity and electrical conductivity were analysed before biochar application, then 6 and 12 months after.ResultsNone of the measured soil physical parameters were affected by the presence or type of biochar. The total porosity was lower during the second production period compared to the first, while available water content and van Genuchten parameters increased during the second production period. No significant difference was observed between soil nitrogen, phosphorus, potassium, cation exchange capacity and electrical conductivity of control and treated plots.ConclusionWe recommend that straw be pyrolysed and the resulting biochar incorporated into soil instead of burying straw (as is actually done in furrow and ridges tillage mode).

Performance of Liquids from Slow Pyrolysis and Hydrothermal Carbonization in Plant Protection

The feasibility of thermochemical biomass conversion technologies can be improved if value-added applications for all fractions can be developed. One of such approaches is the use of liquid by-products from slow pyrolysis and hydrothermal carbonization (HTC) in plant protection. Liquids produced from slow pyrolysis of pine bark, pine forest residues, wheat straw, and willow, and from hydrothermal carbonization of willow, were analyzed in this study. In particular, potential active compounds were analyzed, covering the main volatile, simple organic compounds and numerous phenolic substances. Effectivity tests of the liquids as pest repellent (Arianta arbustorum), herbicide (Brassica rapa), and insecticide (Rhopalosiphum padi) indicated that slow pyrolysis liquid from willow was the most effective pesticide, followed by the liquid from wheat, bark, and forest residues. HTC liquid did not show any pesticidal activity due to low concentration of organic compounds. High content of acetic acid and other carboxylic acids, and the presence of dozens of different phenolic compounds seem to be the main reason for the higher pesticidal activity of willow-derived pyrolysis liquid. Temperature-separated slow pyrolysis liquids proved to be suitable to be used as pesticides. Consequently there is possibility to improve the feasibility of thermochemical biomass conversion technologies remarkably by developing the liquid factions to value-added pesticides.Graphical

Reaction mechanism and evolved gases of larch bark pyrolysis by TG-FTIR analysis

The reaction mechanism and evolved gases of larch bark were investigated using thermogravimetry and Fourier transform infrared spectrometry analysis at 10–50 K min−1. Larch bark pyrolysis starts at approximately 450 K. One peak and one shoulder at low heating rate were observed. This shoulder turns into another peak at higher heating rate. The average value of the final residue is approximately 24%. The average activation energy was estimated as 184.72 kJ mol−1 by the Flynn–Wall–Ozawa method and 201.24 kJ mol−1 by the Kissinger–Akahira–Sunose method, and both have a discrepancy of 8.9%. The sixth or seventh reaction model is responsible for larch bark pyrolysis. The pyrolysis of larch bark produces H2O, CO2, CH4, CO, C=O and others, most of which are released in the temperature range of 500–800 K, except that CO2 has an additional peak value at around 1200 K. In addition, cellulose is the main component in larch bark, and its quantity is larger than that of hemicellulose.

Fast Pyrolysis of Heartwood, Sapwood, and Bark: A Complementary Application of Online Photoionization Mass Spectrometry and Conventional Pyrolysis Gas Chromatography/Mass Spectrometry

Wood offers important potential for biofuel or chemical production by fast pyrolysis but exhibits variable chemical composition that impacts pyrolysis product composition. Here, fast pyrolysis of heartwood, sapwood, and bark isolated from Douglas fir (softwood) and oak (hardwood) was studied by a microfluidized bed reactor (MFBR) combined with single photoionization mass spectrometry (SPI–MS) to provide insights into the wood zone effects on the composition of pyrolysis volatiles. The difference in pyrolysis volatile composition has been clearly unraveled by principle component analysis (PCA) based on the major ions detected by SPI–MS. Some specific product markers have been defined for each wood zone (heartwood, sapwood, and bark) and related to the chemical composition of wood samples (lignin, carbohydrates, and minerals). The catalytic effect of minerals (notably potassium) has a higher impact on carbohydrate decomposition than on lignin decomposition for a given wood type. Therefore, sapwood and heart...

Pyrolysis of Nordic biomass types in a cyclone pilot plant — Mass balances and yields

Fast pyrolysis of biomass results in a renewable product usually denoted pyrolysis oil or bio-oil, which has been suggested to be used as a direct substitute for fuel oil or as a feedstock for production of transportation fuels and/or chemicals. In the present work, fast pyrolysis of stem wood (originated from pine and spruce), willow, reed canary grass, brown forest residue and bark has been performed in a pilot scale cyclone reactor. The experiments were based on a biomass feeding rate of 20kg/h at three different reactor temperatures. At the reference condition, pyrolysis of stem wood, willow, reed canary grass, and forest residue resulted in organic liquid yields in the range of 41 to 45% w/w, while pyrolysis of bark resulted in lower organic liquid yields. Two fractions of pyrolysis oil were obtained, denoted as the condensed and the aerosol fraction. Most of the water soluble molecules were collected in the condensed fraction, whereas the yield of water insoluble, heavy lignin molecules was higher in the aerosol fraction. Based on the results of the present work, willow, reed canary grass and forest residue are considered as promising raw materials for production of pyrolysis oil in a cyclone reactor.

A combined genetic algorithm and least squares fitting procedure for the estimation of the kinetic parameters of the pyrolysis of agricultural residues

The main objective of this study is to implement a two-step fitting procedure to estimate the kinetic parameters of two distinct pyrolysis models to study the pyrolysis of pine bark, wheat straw and rice husk. Thermogravimetric curves were obtained for the three biomass fuels for heating rates of 5, 10 and 15K/min in an inert atmosphere of Argon to investigate the impact of the type of biomass in the pyrolysis behavior under different heating conditions. Distinctive thermogravimetric and differential thermogravimetric curves were obtained owing to the different composition of the biomass fuels. For the conditions examined, the impact of the heating rate on the profile curves was marginal. In order to better understand the impact of the biomass composition in the pyrolysis, their main components were estimated. Additionally, a two-step algorithm was used to calibrate the global kinetic parameters of a single reaction model and of a three parallel reaction model, based on the fitting of predicted curves to the experimental ones. The first step was a genetic algorithm procedure. An evaluation function that minimizes the deviation between the experimental and predicted pyrolysis yields, while preserving the characteristics of the mass decomposition during pyrolysis, is presented in this work. The second step was a least squares minimization that was used for further refining the solution obtained in the first step. The method showed excellent repeatability. For each biomass fuel, all heating rates were globally fitted, with errors of the order of ∼5% for the single reaction model and of less than 1.6% for the three parallel reaction model. The activation energies obtained by fitting each model to the experimental data are generally within the values reported in the literature. Finally, a sensitivity analysis showed that the variation of the composition of each biomass used in this study does not affect significantly the predictions of the three parallel model.

Effect of in-situ addition of alcohol on yields and properties of bio-oil derived from fast pyrolysis of eucalyptus bark

Fast pyrolysis of eucalyptus bark using a free-fall reactor integrated with an in-situ alcohol feeding unit was studied to investigate the effects of feeding positions (in-situ and external), alcohol types (ethanol and methanol) and alcohol content (5–30wt%) on bio-oil yield and properties. The results show that the bio-oil yield decreased with alcohol content from 60wt% (without alcohol) to 40wt% with 30wt% alcohol, whereas the gas yield increased and the char yield remained constant. In-situ addition of alcohol was more effective than external mixing in terms of bio-oil viscosity, stability, water content and pH. Feeding 5wt% alcohol into the process gave similar or better results than external mixing with 30wt% alcohol. Nearly 70% of the viscosity and 30% of the water content were reduced with 5wt% methanol added into the process. The heating value, specific gravity, ash and solids contents were similarly improved by the in-situ and external addition.

The aceramic production of Betula pubescens (downy birch) bark tar using simple raised structures. A viable Neanderthal technique?

Following on from our previous research into the prehistoric aceramic distillation and production of birch bark tar, this series of exploratory experiments investigated the use of raised structures within a fire. These field-based experiments were conducted using sand, gravel, wood fuel, and bark from Betula pubescens (downy birch). The structures that were created were simple raised sand mounds, which reflected known Neanderthal combustion surfaces from the Middle Palaeolithic. The bulk of the experiments were recorded throughout using a thermocouple to provide temperature readings from the base of the bark pyrolysis chamber. The experiments proved successful at producing birch bark tar and several containers were used to catch the tar for later analysis. Based on the results, the authors contend that not only could Neanderthals control fire but that regular birch bark tar production by Neanderthals was most likely a result of specific chaines operatoires in order to provide the necessary control and outcomes.