Co-pyrolysis Char Research Articles

Evaluation of char properties from co-pyrolysis of biomass/plastics: effect of different types of plastics

Co-pyrolysis of biomass/plastics is a viable method to obtain high-quality carbon materials. The synergistic effect in the char production process of co-pyrolysis of biomass/plastics affects the properties of the obtained char. However, the synergistic effect research on the char production process of co-pyrolysis of biomass/plastics is facing challenges owing to highly varying composition of different plastics. In this study, the synergistic effect during co-pyrolysis of bamboo (BM) and plastics (polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET), polycarbonate (PC), and polybutylene terephthalate (PBT)) was investigated. TG results showed that PP, PS, PET, and PBT promoted the release of biomass volatiles and increased co-pyrolysis char yield. Notably, the O-aromatic structure in PC underwent cleavage and deoxygenation reactions, inhibiting the production of co-pyrolysis char during co-pyrolysis process. Char yield from co-pyrolysis process decreased from 24.80% for bamboo pyrolysis to 15.74% for co-pyrolysis of bamboo/PC. The results of physicochemical tests on char samples indicated that the addition of polyhydrocarbon plastics (PP and PS) increased H/C ratio, O/C ratio, heating value and oxidative reactivity of the char compared to bamboo char due to the vapor deposition of hydrocarbons derived from thermal decomposition of plastics on the biomass char. While, co-pyrolysis of biomass and polyester plastics (PET, PC, PBT) improved the pore structure of char and increased oxygen content.

Structure characteristics and gasification reactivity of co-pyrolysis char from lignocellulosic biomass and waste plastics: Effect of polyethylene

The rate limiting stage is char reactivity during gasification that can be influenced by its physicochemical structural characteristics. In this study, the effects of feedstock share, rice straw (RS) and polyethylene (PE), on the physicochemical properties and gasification reactivity of chars were investigated and their relationships were discussed. The char gasification reactivity was investigated via isothermal experiments using a thermal analyzer. The results indicated that the PE addition improved the specific surface area (SSA) and pore volume (Vp) of the char obtained from co-pyrolysis RS with PE. The SSA of the char increased by 1.31 times when the PE content was 60 wt%, compared with that of RS char. The order degree and gasification reactivity of the co-pyrolysis char samples increased with increasing PE content beyond 40 wt%. The char reactivity in the early stage of co-gasification was primarily determined by the order degree of carbonaceous and pore structure. The char reactivity in the later stage was influenced by these two factors and the silicon dioxide content could inhibit the char co-gasification reactivity.

Co-pyrolysis characterization of pre-oxidized lignite and corn stover

In this paper, low-rank lignite and corn stover were pre-oxidized at 200 °C with varying oxygen concentrations (0 %, 6 %, 21 %). The study investigated the effects of pre-oxidation on the physical and chemical properties of lignite and stover, including composition, functional group structure, etc. Subsequently, co-pyrolysis experiments were conducted on the pre-oxidized lignite and stover at 700 °C. The study examined the characteristics of the co-pyrolysis of lignite and corn stover under different oxygen concentrations. The results showed that pre-oxidation could effectively increase the content of fixed carbon in the raw materials, elevate the content of carbonyl and carboxyl groups in the raw materials, and reduce the number of aliphatic hydrocarbon side chains as well as hydroxyl groups. The degree of aromatization of the co-pyrolysis char produced from pre-oxidized lignite and corn stover was enhanced. The 6 % O2 pre-oxidation promoted the pyrolysis degree of the raw materials and intensified the progression of the reaction. The CO2 content of the co-pyrolysis tar was at a minimum of 23.028 % with 0 % O2, and the gas had a maximum calorific value of 11.651 MJ∙Nm−3 at this point. Pre-oxidation had an inhibitory effect on the production of co-pyrolysis tar, and the inhibitory effect became more pronounced with higher concentrations of O2. The higher the oxygen concentration, the more pronounced the inhibition. The addition of oxygen promotes the generation of phenols and ketones in the tar, reducing the content of acids and aldehydes. This improves the quality of the tar but also results in a reduction of aromatic hydrocarbons to some extent.

Synergetic effects during co-pyrolysis of waste textiles and Ca/Fe-rich industrial sewage sludge: Reaction kinetics and product distribution

Co-pyrolysis is a promising technology for industrial organic waste to utilize their unique resource and energy properties for efficient conversion into valuable products. This study was the first time to characterize the co-pyrolysis of waste textiles with Ca-rich industrial sludge and Fe-rich industrial sludge on a laboratory-scale fixed bed. The properties, mechanisms, gas, oil and carbon production were investigated as a function of temperature and mixing type. Co-pyrolysis increased the total weight loss from 50.05 % to 69.81 % for Ca-rich industrial sludge mixed with 50 % waste textiles and from 49.13 % to 70.01 % for Fe-rich industrial sludge mixed with 50 % waste textiles. The activation energy of co-pyrolysis was approximately 50 % lower compared to the pyrolysis of waste textiles alone. The optimal reaction model for the different reaction stages for all samples was three diffusion (D3). Co-pyrolysis resulted in lower CO and CO2 emission temperatures of about 25–110 °C and produced more short-chain organic compounds (C < 10). Co-pyrolysis produced more aldehydes and ketones organics. Moreover, co-pyrolysis char exhibited an elevated level of fatty alkyl side chains and bridge branching, as well as higher degrees of aromatization and stability. This study offers valuable insights into the potential application of pyrolysis for the management of Ca/Fe-rich industrial sludge and waste textiles, thereby serving as a basis for future utilization endeavors.

Co-pyrolysis of municipal sludge and papermaking sludge: Pyrolysis behaviors and heavy metals immobilizations

The co-pyrolysis of municipal sludge (MS) and papermaking sludge (PS) is beneficial for improving the quality of co-pyrolysis biochar and the stability of heavy metals in it. This study investigated the synergistic effect of co-pyrolysis of MS and PS, as well as the influence of different mass ratios (1:9, 3:7, 5:5, 7:3, and 9:1; MS:PS) and pyrolysis temperatures (400–600 ℃) on the physicochemical properties of pyrolysis char, chemical speciation of heavy metals, and their potential ecological risk index. Furthermore, thermodynamic equilibrium calculations were used to study the transformation and stabilization mechanisms of heavy metals during co-pyrolysis. The results indicated that the addition of PS increased the comprehensive pyrolysis index of MS (by 2.09–16.72 times) and the specific surface area of co-pyrolysis char. The inclusion of MS effectively promoted the transformation of heavy metals from unstable fractions to stable fraction, significantly reducing the potential ecological risk index of pyrolysis biochar (by 21.93–41.58 %). The combination of thermodynamic equilibrium calculations and experimental data demonstrated that heavy metals in sludge could be stabilized through the formation of stable heavy metal compounds or their encapsulation within the lattice of inorganic components during co-pyrolysis. These findings suggest that co-pyrolysis of MS and PS is a feasible and promising approach for producing high-quality pyrolysis char with low risk of heavy metals.

Enhancement of H2 and light oil production and CO2 emission mitigation during co-pyrolysis of oily sludge and incineration fly ash

The proper treatment and utilization of oily sludge (OS) and incineration fly ash (IFA) remains a significant challenge due to their hazardous nature. To attain effective recovery of petroleum hydrocarbons and synergistic disposal, this study investigated the co-pyrolysis of OS and IFA, resulting in successful energy recovery, CO2 mitigation, and heavy metal immobilization. Results revealed that the peak ratio of light oil to heavy oil fractions reached 179.42% with 20 wt% IFA addition, accompanied by the highest aromatic hydrocarbons selectivity of 30.72% and the lowest coke yield of 106.13 mg/g OS under the optimal temperature of 600 °C. In-depth analysis indicated that IFA inhibited the poly-condensation of macromolecular PAHs and promoted their cracking into light aromatic hydrocarbons. The addition of 50 wt% IFA significantly increased H2 yield (21.02 L/kg OS to 60.95 L/kg OS) and facilitated CO2 sequestration due to its higher content of Ca-bearing minerals. Moreover, high IFA ratios promoted the reduction of Fe species in OS to a low-valence state. Heavy metals in co-pyrolysis char were well immobilized into stable fractions with lower environmental risks. This work highlights the potential of co-pyrolysis as a viable approach for simultaneous disposal of multiple hazardous wastes and offers new insights for their utilization.

Insight into hydrogen migration and redistribution characteristics during co-pyrolysis of coal and polystyrene

The hydrogen migration and redistribution features in products during co-pyrolysis of coal and polystyrene (PS) were explored using the reactive molecular dynamics (ReaxFF MD) simulations. The weight loss parameters of coal and PS pyrolysis derived by ReaxFF MD simulations agreed well with thermogravimetric (TG) experimental data. The hydrogen transfer route in the co-pyrolysis products was investigated and the hydrogen synergy mechanisms were also elucidated. The results show that the synergistic effect of coal and PS co-pyrolysis can promote char conversion to volatiles, but this effect diminishes from 20.7% to 5.3% (seen from the char yield) as the proportion of PS increases. It is discovered that a large amount of hydrogen migrates from char to volatile in coal, whereas hydrogen migrates from heavy tar to light tar in PS. The content of total hydrogen in heavy tar decreases from 21.47% to 14.06% as PS content increases, whereas hydrogen in light tar increases from 40.27% to 77.76%, indicating an improvement in co-pyrolysis tar quality. The variation of H and O in co-pyrolysis char demonstrates that char formation is highly dependent on the hydrogen/oxygen content. Different levels of hydrogen content cause changes in the dominant reaction and its reaction time in the various char reaction stages, affecting the formation of volatiles.

Co-pyrolysis of dyeing sludge and pine sawdust in a fluidized bed: Characterization and analysis of pyrolytic products and investigation of synergetic effects

Co-pyrolysis of dyeing sludge (DS) and pine sawdust (PS) was carried out in a fluidized bed pyrolyser. The results revealed that addition of PS increased the yields of condensate and gas, and dramatically improved pore structure of co-pyrolysis char, enhancing immobilization of the metals, nutrient and pollution elements. Catalysts (Na-ZSM-5 and HZSM-5) significantly reduced tar and coke, strengthened the integrity of pore structure. Yield of nitrogen-containing compounds declined sharply from 88.66% to 8.14% when 25% of PS was added. Addition of 50% PS promoted ring opening to generate chain compounds and abundant oxygenates (such as ketones, aldehydes and carboxylic acids) in pyrolysis oil (PO) at 650 °C. Correspondingly, yield of gaseous products was inhibited except CO2 and H2 when PS content was dominant. The catalysts greatly increased yield of gaseous products by enhancing primary and secondary cracking depending on different feedstocks and catalysts (e.g., DS over Na-ZSM-5 and PS over HZSM-5). The maximum energy efficiency (69.75%) was obtained at 650 °C when 75% PS was added.

Coal/NH3 interactions during co-pyrolysis and their effects on the char reactivity for NO-reduction: A ReaxFF MD study

In this work, the interactions between NH3 and coal during co-pyrolysis and their influences on char structure and char reactivity for NO reduction are investigated using reactive molecular dynamic (ReaxFF MD) simulations, revealing that coal promotes the thermal decomposition of NH3 because it provides H radicals to attack the N-H bonds in NH3. The primary pyrolysis reactions (thermal breaking of weak covalent bonds) of coal are inhibited by NH3·NH3 also influences the secondary reactions in coal pyrolysis through two aspects: (1) promotes tar cracking to generate gas, and (2) inhibits the polymerization of tar to form char. Compared with coal pyrolysis, the H/C ratio of char and number of O and N atoms in char decrease more slowly during coal/NH3 co-pyrolysis. However, NH3 has little influence on the release of H2S. The effect of NH3 on the physicochemical properties of the char is then analyzed. The oxygen atoms are present mainly as hydroxyl, ether, and carbonyl forms, and the nitrogen atoms are present mainly as cyanide and amino forms in both coal pyrolysis char and coal/NH3 co-pyrolysis char. The coal/NH3 co-pyrolysis char has lower helium density, lower graphitization degree, and larger pores compared with coal pyrolysis char. Finally, the reactivity of coal pyrolysis char and coal/NH3 co-pyrolysis char for NO reduction are examined. The coal/NH3 co-pyrolysis char is more conducive to NO chemisorption and N2 generation. Using a first-order kinetics model, the activation energy of NO reduction reactions on coal pyrolysis char and coal/NH3 co-pyrolysis char are determined as 180 and 123 kJ/mol, respectively.

Pengaruh Komposisi Bahan Baku dan Ukuran Partikel Terhadap Kualitas Biobriket dari Cangkang Buah Karet dan Ranting Kayu

Biobriquette is a solid fuel derived from raw materials that can be renewed continuously because it is made from a mixture of biomass such as wood, twigs, leaves, grass, straw and other agricultural wastes. The research aims to examine the effect of variations in the composition of raw materials and particle sizes were 50 mesh, 70 mesh, 100 mesh, and 120 mesh. This research was started by carrying out the pyrolysis process on the raw material with temperature 350 oC for sixty minutes, then the refined pyrolysis charcoal powder was mixed with starch adhesive 10% of the weight of the raw material which was then manually pressed cylindrical. The measurement results in this research were compared with quality parameters based on Indonesian National Standard (SNI), Japan, England, and America. The best result for this research is obtained at a ratio of rubber fruit shells and wood twigs 1:5 with a particle size of 100 mesh, that is with inherent moisture of 4.50%, ash content of 2.19%, volatile matter of 13.73%, density 2.2502 g/cm3, and caloric value 6,653.60 cal/g.

Co-pyrolysis of low-rank coal and waste truck-tire: A comprehensive study on product distributions, product properties, and synergistic effects

Co-pyrolysis of low-rank coal and waste polymer materials is thought to be a promising way for solid waste disposal and recovering value-added chemicals. In our study, the co-pyrolysis of waste truck-tire (WTT) and Hongliulin low-rank coal (HLL) was carried out in a bench scale fixed-bed reactor to further investigate the synergistic effects during the co-pyrolysis process. The results showed that WTT volatiles inhibited the crosslinking and polycondensation reactions of HLL volatiles to a degree, showing an increase in tar yields. Volatiles-volatiles interactions improved the quality of tar products by enhancing the conversion of heavy components into more light tar, effectively lowering the average molecular weight of tars. The co-pyrolysis produced more chain hydrocarbons and aromatics while producing fewer terpenoids compared with individual pyrolysis, which was attributed mostly to the catalytic effects of char. Volatiles-char interactions increased the graphitization degree and ordered structure of the co-pyrolysis chars, and the pore structure of the co-pyrolysis chars became more developed. The large number of hydrogen-rich radicals produced by WTT pyrolysis consumed the reactive functional groups on the surface of HLL char, resulting in a decrease in the volatiles and cross-linking degree of co-pyrolysis chars. Finally, the potential synergistic mechanism for co-pyrolysis of WTT and HLL was summarized and depicted based on the analysis results.

Nitrogen‑containing species evolution during co-pyrolysis of gentamicin residue and biomass

In the present study, the nitrogen‑containing species evolution in gas-liquid-solid three phases during co-pyrolysis of gentamicin residue and typical biomass was thoroughly investigated. A series of methods for qualitative and quantitative analysis of nitrogen‑containing products were applied. Quaternary-N, pyrrolic-N and pyridinic-N in pyrolysis char, amides, N-heterocyclic chemicals and nitriles in bio-oils, as well as NH3 and HCN in gaseous products were identified. Obviously, the pyrolysis temperature was found to play a crucial role in nitrogen-containing species distribution, where high temperature contributed to the formation of nitrogen-containing species in gas and liquid phases. The plausible evolution avenue for nitrogen-containing species in three phases was also proposed. Furthermore, it is observed that the introduction of biomass (corn cob, corn straw and wheat straw) significantly facilitated the nitrogen transformation into the char from liquid products. In the case of gentamicin residue-to-corn cob mass ratio of 7:3, the nitrogen yield in co-pyrolysis char achieved 43.96 wt% at a temperature of 450 °C, demonstrating the effective fixation of nitrogen-containing species in the presence of biomass. This crucial finding supplies a feasible method for realizing the clean disposal of antibiotic residues and rational construction of nitrogen-containing carbon materials from solid wastes.

Co-pyrolysis characteristics of lignite and biomass and efficient adsorption of magnetic activated carbon prepared by co-pyrolysis char activation and modification for coking wastewater

Activated carbon plays an important role in the field of wastewater treatment due to its excellent adsorption, but improving the recovery and utilization efficiency of activated carbon is a major challenge for its application. In this study, lignite (LC) and poplar leaves (PL) were used as raw materials to prepare magnetic activated carbon (MAC) by co-pyrolysis and char activation modification. The adsorption performance of the product was studied. The results showed that with different blending ratios of LC and PL, a large amount of alkali metal oxides contained in PL had different promoting effects on the pyrolysis of LC. When the mass ratio of LC to PL in the mixture was 3:2, the experimental value of hydrocarbons in the obtained tar reached 53.00%, which was 7.20% higher than the calculated value. The optimal preparation conditions of MAC were determined. Under the conditions of activation temperature of 700 °C, activation time of 2 h, ZnCl2 mass fraction of 30%, impregnation liquid–solid ratio of 3:1 and impregnation time of 16 h, the activated carbon exhibits a relatively desirable performance. The obtained products were characterized by VSM, XRD, FT-IR, N2 adsorption and SEM. As a result, the obtained MAC exhibits a better porous structure and higher specific surface area, and Fe3O4 was observed on the surface of the MAC. The adsorption performance of coking wastewater by MAC was studied. We demonstrate that the prepared MAC could effectively adsorb organic matter in wastewater. After MAC was used to adsorb the coking wastewater for 3 h, the COD concentration in the wastewater decreased from 280 to 60 mg/L, and the MAC could be effectively recovered by magnets after adsorption.

Preparation of Magnetic Activated Carbon by Activation and Modification of Char Derived from Co-Pyrolysis of Lignite and Biomass and Its Adsorption of Heavy-Metal-Containing Wastewater

Adsorption with activated carbon (AC) is an important method for the treatment of heavy metal wastewater, but there are still certain challenges in the separation and reuse of activated carbon. The preparation of magnetic activated carbon (MAC) by modifying AC is one of the effective means to realize the separation of AC from solution after the adsorption process. In this work, lignite and poplar leaves were used as raw materials for co-pyrolysis, and the co-pyrolysis char was activated and modified to prepare MAC. The structure and properties were characterized by VSM, N2 adsorption, SEM, XRD, and FT-IR. At the same time, the adsorption performance of MAC on wastewater containing Pb and Cd ions was studied. The results show that the prepared MAC contains Fe3O4, and the saturation magnetization (Ms) of the MAC is 13.83 emu/g; the specific surface area of the MAC is 805.86 m2/g, and the micropore volume is 0.23 cm3/g; the MAC exhibited a good porous structure. When the pH value of the solution was 5, the adsorption time was 120 min, the dosage of MAC was 4 g/L, the initial concentration of Pb ion solution was 50 mg/L, and that of Cd ion solution was 25 mg/L, and the adsorption temperature was 30 °C, the adsorption efficiency of Pb, Cd ions were 84.40 and 78.80%, respectively, and the adsorption capacities were 10.55 and 4.93 mg/g, respectively. The adsorption of Pb and Cd ions by MAC conforms to the Langmuir adsorption model, which is a monolayer adsorption. The adsorption process is mainly chemical adsorption, which can be better described by the pseudo-second-order model. The adsorption thermodynamic analysis showed that the adsorption of Pb and Cd ions by MAC was a spontaneous reaction, and the higher the temperature, the stronger the spontaneity.

Pyrolysis Characteristics of Hailar Lignite in the Presence of Polyvinyl Chloride: Products Distribution and Chlorine Migration

This study investigated the effects of polyvinyl chloride (PVC) addition on low-rank coal’s pyrolysis characteristics, especially the products distribution and chlorine migration. Hailar lignite (HLE) with different industrial, pure, PVC-content additions were prepared (the mass percentage of PVC addition was from 5% to 25%), and the co-pyrolysis characteristics of HLE and PVC were performed on a fixed-bed reactor and thermogravimetric analyzer. The chars were characterized with X-ray diffraction (XRD), X-ray fluorescence (XRF), and Fourier-transform infrared (FT-IR) spectroscopy analysis. The gas and tar compositions were analyzed by using gas chromatography (GC) and a gas chromatography–mass spectrometry (GC–MS) system, respectively. The results indicate that the addition of PVC can increase the release amounts of CH4, C2H4, and C2H6, simultaneously reducing the release amount of CO2 and CO; the quality of pyrolysis tar was also improved, especially the alkane content in tar, which increased by 6.9%. The migration of chlorine in PVC was analyzed with the different PVC additions and terminal pyrolysis temperatures. It showed that the content of chlorine in the gas phase first increased with the increasing pyrolysis temperature, but at the terminal temperature of 600 °C, the chlorine in the gas phase began to decrease. The results of the co-pyrolysis char characterization show that the content of the alkali metal oxide gradually decreases in the char, and metal chloride appears during the pyrolysis process. In the co-pyrolysis reaction of coal and PVC, chlorine was fixed in the char, thereby reducing the distribution of chlorine in the gas phase. This also proves that the PVC pyrolysis process, with the participation of low-rank coal, can enrich chlorine into the solid phase, thus reducing the emission of chlorine in the gas phase.

Investigation into the interaction of biomass waste with industrial solid waste during co-pyrolysis and the synergetic effect of its char gasification

In this work, the interaction between waste cypress sawdust (WCS) and coal liquefaction residue (CLR), a type of industrial solid waste, during co-pyrolysis was studied by thermogravimetry-mass spectrometry (TG-MS) and pyrolysis-gas chromatography mass spectrometry (Py-GC/MS). The gasification reaction characteristics of co-pyrolysis char were also evaluated. The results showed that both promoting and inhibiting effects existed in the co-pyrolysis process of WCS and CLR. When the pyrolysis temperature was less than 420 °C, the catalysis of minerals was conducive to the pyrolysis reaction. At higher temperatures, the polycondensation and carbonization produced by the interaction between the components inhibited the release of volatiles. The gasification reactivity of co-pyrolysis char was better than that of individual WCS and CLR chars. The synergistic effect was most obvious when the blending ratio of WCS to CLR was 3:1. In the gasification process of co-pyrolysis char, the WCS component with better reactivity preferentially reacted to form an abundant pore structure, which exposed more reactive sites and promoted the diffusion and mass transfer of gasification agent. Moreover, alkali and alkaline earth metal species in WCS and iron bearing minerals in CLR can catalyze the gasification reaction, contributing to the synergistic effect. Therefore, the addition of a suitable solid waste to biomass waste can improve the energy efficiency and simultaneously achieve solid waste utilization.

Study of Pore Length and Chemical Composition of Charcoal that Results from the Pyrolysis of Coconut Shell in Bolaang Mongondow, Sulawesi, Indonesia

Charcoal of coconut shell is produced by pyrolysis at 300oC and chemically activated using HCl. Both pyrolysis charcoal and chemical activation were measured and analyzed by Fourier Transform Infrared (FTIR), Scanning Electron Microscopy (SEM), and Energy Dispersive Spectroscopy (EDS). The functional groups found O-H, aliphatic C-H, aromatic C=C, C-O, and aromatic C-H. The distribution of pyrolysis charcoal pore length and chemical activation increased from 362 nm-1.02 µm to 1.10 µm-1.52 µm. The composition of carbon elements in the mass % of pyrolysis charcoal and chemical activation increased from 86.11% to 88.93%.

Co-pyrolysis of lignocellulosic biomass and plastics: A comprehensive study on pyrolysis kinetics and characteristics

Co-pyrolysis of biomass with plastics is an interesting research trend in improving both the yield and quality of oil products toward taking advantage of flexible material resources and sustainable fuel development. This study investigated the kinetic behaviors using thermogravimetric analysis and pyrolysis characterization for the co-pyrolysis of biomass (bamboo and oak wood) with plastics (polypropylene [PP] and polystyrene [PS]) in a fixed-bed reactor. The kinetic triplet for feedstocks was determined using the isoconversional method, compensation effect, and master plot method. The addition of 20 wt% plastics into biomass decreased the activation energy, with the most distinct positive synergistic effect for the bamboo/PS blend. In addition, the effect of co-pyrolysis temperature and biomass/plastic ratio on pyrolysis characteristics was investigated. Through biomass pyrolysis and biomass/plastic co-pyrolysis, the positive changes in distributions and physical-chemical properties of the products (i.e., char, oil, and gas) were observed using various analytical methods. Especially in the case of biomass/PS blends, the synergistic effect of co-pyrolysis was shown due to the difference in the actual and theoretical yields of the products. The liquid yields of the co-pyrolysis were 50.95, 50.17, 55.15, and 56.16 wt% for bamboo/PP, bamboo/PS, oak wood/PP, and oak wood/PS, respectively. The highest HHV of 28.22 MJ/kg was obtained for oil derived from the co-pyrolysis of bamboo/PS. Furthermore, co-pyrolysis chars have high HHVs in the range of 30.73–32.41 MJ/kg, suggesting that they can be used as solid fuels.

Structural and gasification kinetic studies on co-pyrolysis chars of coal and biomass

G(X): a function describing the effect of ash and carbon matrix evolution on gasification reaction rate.

Synergistic effect on thermal behavior and product characteristics during co-pyrolysis of biomass and waste tire: Influence of biomass species and waste blending ratios

The work aims to get a full understanding of the co-pyrolysis synergy between different biomass and waste tire for high value utilization of both biomass and waste tire. Rice husk (RH), wheat straw (WS) and moso bamboo (MB) were chosen to co-pyrolyze with waste tire (WT). Influence of biomass species and blending ratios on co-pyrolysis synergistic effect was studied by analyzing thermal behavior, product yields and character. Thermogravimetry analysis proved the existence of synergistic effect and measured positive decomposition synergy for MB/WT. Char production showed little synergy for all biomass during co-pyrolysis while positive synergistic effect in liquid production was weakened with WT blending. Co-pyrolysis char integrated both biomass char and WT char characteristic. The pore structure was corresponding to that of biomass char and improved by synergy for all biomass, especially WS and MB. Co-pyrolysis oil mainly consisted of the typical components of bio-oil and WT oil, showing lower oxygenated compounds percentage than bio-oil. Aromatic hydrocarbons formation was inhibited while alicyclic hydrocarbons formation was intensified by co-pyrolysis interaction and MB/WT co-pyrolysis showed significant synergy in ethers and furans production. Co-pyrolysis showed positive synergistic effect on CO and CO2 generation and negative synergistic effect on H2 and CH4 content.